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VIII.

Tyndall’s ‘“* Lectures on Light ”
Lockyer’s ‘‘ The Spectroscope and its Moieatione*

[The Copyright of Articles in this Fournal is Reserved.|

CONTENTS: OF) + No. XE.

THE SATURNIAN SysTEM. By Richard A. Proctor, B.A.,
SceskcA.S. . : : - : : : -

ON THE RELATION BETWEEN REFRACTED AND DIFFRACTED
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OBSERVATIONS ON THE OPTICAL PHENOMENA OF THE
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RECENT CHANGES IN BRITISH ARTILLERY MATERIEL. By
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Proctor’s * Light Science for Leisure Hours ”’
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34

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67

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Gillmore’s ‘‘ Report on Béton Aggloméré ”’

Gillmore’s ‘ Practical Treatise on Limes, Hydraulic Cements,

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Bain’s ‘* Mind and Body ”

Sir John Lubbock’s “* Origin and Meenas of Inseéts ”

Fox’s *‘ Ozone and Antozone ”

Atkinson’s “‘ Ganot’s Elementary Treatise on Physics ”

Althaus’s ‘‘ Treatise of Medical Electricity ”

Saltzer’s ‘‘ Treatise on Acoustics ”

Blackley’s ‘‘ Experimental Researches on the Causes and Nature

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Baker’s ‘‘ Long Span Bridges”’

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THE QUARTERLY

PouURNAL.OF SCIENCE,

JANUARY, 1874.

re oTHE SATURNIAN) SYSTEM,

By RicHarD A. Proctor, B.A. (Cambridge).
Author of “ Saturn,” “The Sun,” ““The Moon,” &c.

[7 has always appeared to me, since first I studied the
subject of Saturn and his system, that our books on
astronomy fail to indicate effectively the position which
this noble planet, and the scheme over which he holds sway,
bear in the economy of the solar system. The remark extends
to Jupiter, and in a less degree to Uranus and Neptune.
There is to my mind something most incongruous between
the true teachings of .astrenomy respecting the giant planets,
and the notions complacently presented in book after book
on elementary astronomy, and even in treatises by masters
of the subject. We have the astronomy of the ancients
and the modern astronomy intermixed. We see rightly
taught the dimensions and general aspect of the different
planets, but we find these bodies classed together precisely
as they very reasonably were when astronomers knew
little more than that there are, besides the sun and
moon, the planets Mercury, Venus, Mars, Saturn, and
Jupiter. The orbits of these bodies are plotted down in
a series of concentric and equidistant circles, on which
very commonly are shown pictures (save the mark) of
the several planets, and the reader is left to combine the
utterly erroneous notions thus indicated with such ideas as
he may derive from the array of numbers contained in the
tables of planetary elements. Nor in the verbal description
of the planets is any stress laid upon the characteristic
peculiarities which distinguish the outer family of planets
from the inner. Differences are stated, but mere statement
in such cases counts for very little; the impression really
conveyed is, that whereas the earth, and Mars, and Venus,
and Mercury are so many smaller worlds, Jupiter, and
Saturn, and Uranus, and Neptune are as many larger
worlds ; and whatever peculiarities distinguish these outer
‘and larger planets from the rest are discussed with direct
VOL. IV. (N.S.) B

a The Saturnian System. {January,

reference to familiar terrestrial relations. For instance, if
the satellites of Saturn are referred to, the remark is made
that the external skies of Saturn must be well illuminated,
and very beautiful with all these moons, when our own
single moon forms so beautiful a feature of our nights.
When the rapid rotation of Saturn is mentioned, we are
told immediately that therefore the day in Saturn lasts only
so many of our hours. So withthe Saturnian year, because
the mean density of Saturn is but about 13-1ooths
of the earth’s; we are told that, therefore, his globe is
construéted of material as light as ‘mahogany ; and so on,
through a variety of such comparisons.

It appears to me that the history of investigations into
the physical condition of the planets is chara¢terised by a
very singular unreadiness to view the whole subject from
the new standpoint, available when telescopic observations
began to be made. The new knowledge gained by means
of the telescope was welded to the old ideas respecting
the planets. New cloth was added to old garments. The
natural course, one would have supposed, would have been
to consider the planets altogether in the light of information
obtained by the telescope, simply because that was the first
really reliable information obtained by astronomers. Every-
thing until then had been guess work; yet the results of
such guess work still appears in our books on astronomy.
It is not Saturn or Jupiter, as revealed by the telescope,
with which our writers on astronomy deal; but they tell us,
in effect, that the Saturn and Jupiter of the old astronomers
have been found to have such and such dimensions,
rotation-rates, aspect, and so on.

Accordingly, the attempt to reason respe¢ting these planets
in perfect independence of the ideas entertained ages ago by
astronomers, is regarded as a species of innovation. That
is held to be rash and fanciful speculation which in point of
fact is the only scientific way of treating the subject. It is
held to be a sort of heresy to speak of Saturn or Jupiter
in terms not stri€tly compatible with the words of Sir
W. Herschel, for example, although his ideas respe¢ting
these planets were based entirely on the ideas formerly
entertained about them, and conveyed to Sir W. Herschel
through the instruCtive but not very suggestive teachings of
Ferguson. I have not, indeed, myself had to complain on
this point. I have, in faét, been surprised at the exceedingly
liberal manner in which my own theoretical opinions have
been received—I may even say welcomed—by many who, |
nevertheless, still retain a prejudice for the older way of

1874.) — The Saturnian System. 3

treating the subject. But I observe that other writers have
been less fortunate; and when they have indicated the
significance of the features which distinguish giant planets
from the terrestrial planets, and touch on some of the
conclusions flowing from such considerations, their views
are scouted as wild and fanciful—too startling, in fact, to
obtain acceptance among men of science.

In passing, I would touch on the objection to startling
views, merely because they are startling, as utterly unreason-
able in the presence of all that has been discovered, not
merely in astronomy, but in science generally. The accepted
truths of science are nearly always startlingly unlike what
has been imagined before the evidence became strong
enough, or was well studied enough, to indicate the real
facts. Take, for instance, what has been learned recently
about the sun. Suppose that twenty years ago the now
known truths about the constitution of the sun, about
coloured prominences, and about the corona had _ been
simply enumerated, either as the result of theoretical
considerations or of observations the nature of which was
not made known: then it is certain that the surprising
character of these new views would have _ rendered
them unwelcome to astronomers. Less startling theories
would have been received with favour, and quoted as
altogether preferable to notions so bizarre and fanciful; yet
the sober theories of twenty years ago were wide of the
truth. They were in reality fanciful, and though not far
fetched, yet ill fetched ; drawn, in fact, from utterly incorrect
analogies.

It may be assumed, indeed, ordinarily, that the relations
as yet unknown are such as we should regard as surprising.
It is not merely an unsafe, but an almost certainly mis-
leading assumption that the best explanation of facts is the
one which is most obvious and natural. What can be
more natural, for instance, than the theory that the solar
corona is due to the passage of the sun’s rays through our
own atmosphere ?—what more utterly misleading? How
natural was Faye’s theory that the solar sierra is a
phenomenon produced by the lunar atmosphere; and yet
the theory was altogether and demonstrably unsound. ‘To
go farther back in the history of astronomy, the Ptolemaic
theory was unquestionably intended to explain in the most
natural way the celestial motions observed from our earth,
obviously fixed, obviously far larger than any of the heavenly
orbs. Even more natural and seemingly obvious is the
theory that the earth is a great plain. ‘The true theory in

4 The Saturnian System. [ January

these and hundreds of other instances has not been the
theory which commended itself by its obviousness and by
its close accordance with what was mistakenly regarded as
the natural order of things.

I propose in the present essay on the Saturnian system
to begin with the consideration of known faéts about Saturn
and his system, and from them to endeavour to educe just
ideas respecting the constitution of the Saturnian system,
proceeding in perfect independence of all preconceived
opinions. I shall neither endeavour to support nor to over-
throw the common notion that Saturn is a globe resembling
our earth in nature, though larger and in certain details unlike
the earth. I shall endeavour as far as possible to treat my
subject as though the earth were not the sole orb in the
universe with which we have a close acquaintance.

In the first place; then, let us consider Saturn’s position in
the solar system, as respects mass, the most important
element of a planet’s condition, simply because the mass of
a planet measures the planet’s power.

Regarding the solar system as a whole, we see the sun so
largely surpassing all the planets together in mass and
volume, that if we knew nothing else respecting him, we
should recognise the fact that he belongs to another order of
created things. He does not surpass the several planets
only, but all the planets taken together.

But we are apt to overlook the fact that Jupiter and
Saturn are as markedly distinguished from the earth and
Venus as the sun is from the giant planets. Jupiter
alone surpasses all the members of the inner or terrestrial
family of planets, taken together, about a hundred and forty
times. Saturn surpasses them all, taken together, about
forty times. A difference such as this can hardly be
described as one of degree merely. It is a difference of
kind, so far as mass can indicate such a difference. It
seems a sufficient proof of this to note that if the sun were
destroyed as well as Saturn, Uranus, and Neptune, then
Jupiter could effectively replace the sun as a ruling orb,
round which the terrestrial families could travel, not indeed
on such wide orbits as at present, but on paths of great
extent, Jupiter remaining as appreciably stable at the centre
of the scheme as the sun now is. ‘The like can be said
about Saturn, since his mass exceeds that of the earth—
the largest member of the family of minor planets—about
ninety times.

Even taking into account Uranus and Neptune, Jupiter
and Saturn are supreme among the members of the solar

1874.] The Saturnian System. 5

system. Jupiter | is indeed easily first, seeing that he
surpasses about 2} times (in Mars) all the other members of
the family, including Saturn, taken together. But Saturn
is as easily second, seeing that he in turn surpasses all the
other members of the planetary scheme, taken together,
nearly three times.

Still it is, when we compare either Jupiter or Saturn with
the members of the terrestrial family of planets, or rather
with that family as a whole, that we perceive most clearly
that those giant planets belong to another order of bodies.
Our earth does not to the same degree surpass the family of
asteroids regarded as a whole. It is indeed rather surprising
that the asteroids should so readily have been recognised as
belonging to a distiné& order, while the giant planets, which
differ fully as much from the terrestrial family of planets as
these planets differ from the asteroids, should be regarded
as though they were members of one and the same
family.

It may be urged, perhaps, that the asteroids by travelling
altogether within a comparatively small region of the sun’s
domain seem marked out as forming a distinct family. But
in truth, the region within which the asteroids pursue their
path is very much larger than that occupied by the members
of the terrestrial family of planets—certainly twice as large,
if we leave altogether out of account the great range of the
asteroids in distance from the mean plane of the solar
system. The orbital range of the terrestrial family of
planets is indeed so small, compared with that of the outer
family, that the two sets of orbits cannot be properly
represented in the same diagram. If a diagram includes
the orbits of the giant planets properly drawn to scale, then
the path of Mars, the outermost of the terrestrial planets,
is represented by a circle considerably smaller than that
commonly used to represent the sun in ames of the solar
system.

Let us endeavour, then, to picture to anrSEInee the giant
globe of Saturn pursuing its career so far from the central
orb that the region girt round by its orbit exceeds more than
ninety-fold the region which the earth circuits in her annual
revolution. Let us remember that in precisely the same
degree the solar light and heat are reduced at Saturn’s
distance, and (also in the same degree) the attractive
influence of the sun, and singularly enough, in the same
degree, Saturn’s own attractive influence exceeds the earth’s.
For the former relation was a necessary consequence of the
law according to which light, heat, and gravity diminish

6 The Saturnian System. (January,

with distance ;* but the latter is, as it were, accidental, since
there is no necessary connection between the mass of any
planet and the distance at which it travels. It is worthy of
notice, as a convenient aid to the memory, that while the
area swept out by Saturn is about ninety times that swept
out by the earth, and solar heat, light, and gravity at Saturn
about one-ninetieth less than at the earth, the mass of
Saturn exceeds that of the earth about ninety-fold. It is
manifest, then, that Saturn must be regarded as a much
more efficient ruler over the region of space along which he
circles than the earth can possibly be over the region
of space through which she travels. Or rather, it is
manifest that the range of Saturn’s influence is much
wider. So feeble is the earth, so narrow is the sphere
of her special influence, that even her own moon is far
more fully under solar influence than under terrestrial
rule. In fact, if we remember that the sun’s mass is about
315,000 times that of the earth, we see that his influence
equals hers at any point whose distance from the sun is to
that from the earth as the square root of 315,000 to unity,
or about as 561 tor. Now since the distance of the earth
from the sun is about 91,500,000 miles, a point on the line
joining the earth and sun (and between these bodies)
must be distant from the earth 1-562nd part of this distance
to be equally influenced by the sun and earth. This
distance is rather less than 163,000 miles, whereas the
moon’s distance from the earth amounts to 238,800 miles.
A point beyond the earth on the line joining the sun and
earth produced should be at 1-560th part of g1,500,000 miles
from the earth, to be equally influenced by the earth and
sun, that is about 164,000 miles. This is the farthest point
from the earth at which her influence equals that of the
sun; and if a sphere be described in space at any instant,
having the line joining this last-named point and the one
before determined (163,000 miles from the earth’s centre
towards the sun) as diameter, then at all points within this
sphere with its diameter of 327,000 miles or thereabouts,
the earth acts more potently than the sun; but everywhere
else she acts less potently. Now let us apply a similar
process to Saturn, in order to ascertain the dimensions of
the sphere over which his power is, as it were, supreme, and

* Since the area swept out by a planet in completing its orbit varies directly
as the square of the mean distance, while light, heat, and gravity vary inversely
as the square of the mean distance, it follows that the light, heat, and attraction
influencing bodies revolving around the same central sun vary inversely as the
area of their orbits.

1874.] The Saturman System. a

we shall at once perceive how different is his position as a
ruler of matter compared with that of the earth. The mean
distance of Saturn from the sun amounts to 872,137,000
miles, and his mass is about go times the earth’s, or about
I-3500th of the sun’s mass. Hence the sun’s influence
equals Saturn’s at any point whose distance from the sun
is to that from Saturn as the square root of 3500 to unity,
or about as 59 to £. Hence a point on the line joining
Saturn and the sun, and between these bodies, must be
distant from Saturn 1-60th part of the distance of Saturn
from the sun to be equally influenced by the sun and
Saturn. This distance is about 14,500,000 miles from
Saturn on the side towards the sun. On the farther side, a
point equally influenced by Saturn and the sun would lie at
a distance from Saturn equal to 1-58th part of Saturn’s
distance from the sun, or at a distance of about 15,000,000
miles. Hence the sphere over which Saturn bears supreme
sway has a diameter of 29,500,000 miles. We have seen
that the sphere over which the earth bears supreme sway
has a diameter of only 327,000 miles. Hence Saturn’s
sphere of rule is to the earth’s, in diameter, as 29,500
to 327, or is about go times greater.* Here strangely
enough the proportion go to I comes in yet again, not as
the reader might imagine at a first view, as a necessary
consequence of the same proportion go to I in the mass of
Saturn compared to the earth’s, and in the square of his
mean distance to the square of the earth’s, but inde-
pendently—since it would not have appeared as the result
of our calculations did not the sun’s mass bear to Saturn’s
the proportion 3500 tor. The volume of the sphere ruled
over by Saturn bears to the volume of the sphere ruled over
by the earth a proportion of about 730,000 to unity; and it

* It may be interesting to determine in the same way the extent of the
sphere over which Jupiter bears sway. His mean distance from the sun
amounts to 475,692,000 miles, and his mass is equal to about one ,,,,th part
of the sun’s. Hence the influence of Jupiter and the sun are equal at any
point, whose distance from Jupiter is to its distance from the sun as I to the
square root of 1048, or as 1 to about 32. Hence we must take from Jupiter
on the side towards the sun a distance equal to ,',rd part of Jupiter’s distance,
and on the side away from the sun a distance equal to ,st part of Jupiter’s
distance. These distances are respectively about 14,400,000 miles, and about
15,300,000 miles; so that the sphere over which Jupiter bears superior sway
has a diameter of about 29,700,000 miles, which may be regarded as about
equal to the diameter of the sphere over which Saturn bears superior sway,
I have spoken of the region over which a planet bears special sway as a
sphere, and this is actually the case. It is manifest from the reasoning that
the planet is not centrally placed within the sphere, but is nearer the side
towards the sun. The sphere is manifestly not constant in dimensions, being
larger or smaller, according as the planet is farther from or nearer to the sun.

8 } The Saturnian System. (January,

may not unfairly be said that this proportion indicates the
relative position of the two orbs—Saturn and the earth—as -
respects power in the scheme of the planets. This pro-
portion seems certainly more truly to indicate their relative
power than the direct proportion between their masses—
since we must recognise in the earth’s relative proximity”
to the sun a source of comparative inferiority as a ruler
over matter. It is noteworthy, moreover, that if we adopt
this criterion, Saturn and Jupiter are brought almost to
equality, notwithstanding the greatly superior mass of the
last named planet.

It is to be noticed that the relation here considered bears
very importantly on the question of the original formation
of the planetary system. I must admit that, for my own
part, I find much in Laplace’s conception of the genesis of
the solar system, which is very far from satisfactory. A
gradually contracting nebulous mass, such as he pictures,
could scarcely in my opinion have produced a system in
which the masses are at a first view so irregularly scattered
as in the solar system. But if we adopt such a view as I
have endeavoured to maintain in my ‘‘ Other Worlds,” we find
in the position of the various members of the solar system
a satisfactory reason for their various dimensions. Accord-
ing to that view the solar system had its origin in the
gathering together of matter towards a great centre of
aggregation. The subsidiary centres of aggregation which
would as naturally arise during such a process as subsidiary
whorls in a gigantic whirlpool, might be expected to have
such dimensions as we actually observe. Close to the great
centre, such centres would be relatively small, because the
ruling centre would be supreme everywhere within the
sphere close around him, except quite close to subordinate
aggregations. No matter except such as passed very close
to such aggregations would be gathered in. We may
suppose that such aggregations would indeed only form on
account of the enormous wealth of matter within that
sphere, and the consequent certainty of collisions, or very
close approaches resulting in agglomeration; and towards
the outskirts of this part of the sphere of the sun’s
influence there would not even be any definite agglome-
ration, but a number of very small—and, as it were,
accidental—aggregations resulting in the ring of asteroids.
Outside the sphere of the sun’s overmastering influence,
there would still be a great wealth of matter, and gathering
aggregations would exert their attractive energies far more
widely. Nearest of all to the central region would come

1874.] The Saturnan System. 9

the mightiest aggregation of all, on account of the greater
quantity of matter. Here, then, Jupiter had his birth, chief
giant of the solar system, and prince of all the planets.
But the range of sway would widen with increasing distance,
and at first such widening would go far to counterbalance the
gradual falling off in the gravity of matter. Moreover,
with increase of distance from the sun would come a greater
freedom to form out of the aggregating matter subordinate
schemes or systems. Next, then, beyond Jupiter, with his
giant bulk and uniform system of secondary bodies, came
Saturn into being, inferior in mass to his giant brother, but
ruling over a wider space, separated from Jupiter by a far
greater distance than separates Jupiter from the asteroids,
and in fact, according to the criterion I have laid down above,
nearly the equal of Jupiter in the range of his independent
power. Here we see the origin of the most remarkable
system within the solar domain—a scheme of rings whose
complicated structure is as yet not half understood, anda
family of eight satellites as diverse in size and arrangement
as the eight primary members of the solar family itself;
and we can readily understand how, with yet increasing
distances and continually decreasing quantity of matter, the
minor but still gigantic masses of Uranus and Neptune
should appear on the outskirts of the solar system. I
venture to predict, with some degree of confidence, that
if. any trans-Neptunian planet be ever discovered, it will
be inferior, but not greatly inferior, to both Uranus and
Neptune in mass.*

Let us now, however, turn from the consideration of the
mass and weight of Saturn, and of the processes by which
he may be thought to have reached his present condition,
to the inquiry what that condition probably is.

We see Saturn, then, the centre of a scheme of wonderful
extent and importance. The outermost satellite circuits in
an orbit having a diameter of more than 4,600,000 miles.
This is the widest span of any satellite orbit, and not far
short of ten times the span of our moon’s orbit. The widest
span of the Jovian satellite system amounts to but 2,380,000
miles, or almost exactly five times the span of the moon’s
orbit. It will be observed that both the Saturnian and

* In old times this would have been a tolerably safe prediction, since any
such planet would have been very unlikely indeed to be discovered. But in
these days, when the zodiac is continually being swept for the discovery of
new planets, and when new planets are being detected at an average rate of
about five per annum, it is exceedingly unlikely that any trans-Neptunian planet
will long escape detection, supposing any such planet exist to be detected.

VOL. IV. (N.S.) Cc

10 The Saturnian System. [January ;

Jovian satellite systems lie far within the limits of the
spheres ruled over with superior sway by these planets
respectively. For it will be remembered that Saturn’s
sphere of sway has a diameter of about 29,500,000 miles,
while Jupiter’s (see note at p. 7) is about 200,000 miles
wider. The effect of this is seen in the motions of the
Jovian and Saturnian satellite systems. For whereas the
orbit of our moon around the sun is everywhere concave
towards the sun, notwithstanding the motion of the moon
round the earth, the paths even of the outermost of the
Jovian and Saturnian satellites are markedly convex towards
the sun when these bodies are in inferior conjunction. The
inner satellites, in fact, not only move at those times on
courses convex towards the sun, but have an excess of
motion in their orbit round their primary over the onward
motion which they share with him around the sun, and
consequently travel backwards in this part of their motion.
It follows that in successive lunations the inner satellites
trace out looped paths. This happens with the four
satellites Mimas, Euceladus, Tethys, and Dione. ‘The
fifth, Rhea, shows the singular peculiarity of coming almost
exactly to rest when in inferior conjun¢tion—that is, to rest
relatively to the solar system. The path of this satellite
with reference to the solar system is nearly an epicycloid,
any portion of which, from cusp to cusp, is appreciably a
cycloid. ‘The satellites Titan, Hyperion, and Japetus follow
waved courses convex to the sun through a considerable
portion of each lunation. It will be seen that Saturn
has his system in complete control.* Even the outermost
is very much less perturbed by the sun (relatively as well as
absolutely) than our moon.

The second satellite inwards has an orbit diameter of
rather more than two millions of miles. It is a somewhat
remarkable circumstance that this satellite, lying between
Titan and Japetus, the two largest satellites, should be the
smallest or at least the faintest of all Saturn’s satellite

* The distinction between our moon and the satellites of the major planets is
a marked one, and significant. Our moon is, in point of fact, much more to be
regarded as a fifth planet of the inner family of terrestrial planets than as an
orb dependent on ourearth. If she could be watched from a distant standpoint,
her motions would scarcely indicate the fact that she circles around the earth;
for, in fact, the result of this so-called circling motion corresponds simply to large
perturbational effects. _Onthe contray, the motions of the satellites of Jupiter,
Saturn, Uranus, and Neptune, are chiefly influenced by their respective
primaries, and this could not but be recognised if the motions of these moons
were watched from a distant point. Even if their primaries were concealed
during the observation, the motions of the satellites would reveal the fact that
these bodies are ruled by a central orb.

1874.] The Saturnian System. II

family. One would be led to suspect that Hyperion is but
one member of a zone of small satellites travelling between
the paths of Titan and Japetus. It appears to me to bea
confirmation of this view that the path of Hyperion does
not correspond with the general arrangement of the scheme,
but bears somewhat the same sort of relation to it that we
should recognise in the orbit of one of the innermost of the
asteroids if taken, instead of the zone of asteroids, to
represent the orbit intermediate to the paths of Mars and
Jupiter.

As we proceed onwards towards Saturn we are struck
with the comparatively close order of the orbits of the inner
satellites. The distance separating the orbit of the inner-
most from that of the fifth Rhea is less than half the
distance separating the orbit of Rhea from that of Titan
the sixth. The following table of distances has been
calculated on the assumption that the sun’s equatorial
horizontal parallax is 8°g16” :—

N Distance in mean Distance Difference.
ane: radii of Saturn. in miles. in miles.
Ee Mimas 3°3607 1152333 2,66
II. Euceladus 4°3125 148,000 : ie 3
TT. Tethys 5°3396 183,250 ee a
IV. Dione 6°8395 ZANT i ie
Ni Rhea 9°5528 527:540 ee
VI. ‘Titan 22°1450 759,999 Ta0"Ro

VII. Hyperion 26°7834 919,170
VIII. Japetus 6 4°3590 2,208,720 7789550

Passing yet farther inwards, after crossing the orbit of
Mimas, we come upon the ring-system. The outer edge of
the outer ring lies at a distance of 83,460 miles from the
centre of Saturn, or 31,875 miles from the orbit of the
innermost satellite. It is noteworthy how uniformly the
distances from this ring outwards to orbit after orbit of the
four inner satellites proceed. This uniformity somewhat
resembles what we notice in the case of the four terrestrial
planets, since we see that the distance from the sun to
Mercury, thence to Venus, and thence to the earth, are very
nearly equal (being roughly 35, 32, and 35 millions of miles),
while the distance to Mars, though greater, belongs to the
same order of distances. ‘The remaining elements, which
are convenient for reference in treating of the ring-system,
are the following :—

12 The Saturnian System. |January,

Exterior diameter of outer ring in miles . . 166,920

Interior af PP ¥
Exterior : °’,; inner ring ,, 1. CE
Interior 3 if ie . Sega
Interior SS dark ring ,, i? Tomiie
Breadth of outer bright sing ss 2) Uc 18. 9,025
Breadth of division between rings . . . . 1,680
Breadth of inner brightring . . . . . + 17,605
Breadth of dark ring. splay WeanE 8,660

Breadth of system of bright rings . ciel oP
Breadth of ‘entiré'system ‘of rings ©. '. °.)°) 39,57@
Space between planet and dark ring. Bret 9,760

We are thus brought to the planet’s globe. Its mass we
have already indicated. Its dimensions are as follows :—
the equatorial diameter is about 70,150 miles, the polar
diameter about ths less, or about 63,500 miles. The
volume exceeds the earth’s 697 times, so that since in mass
Saturn only exceeds the earth about go times, his mean
density is but about ?%ths of the earth’s. His globe rotates
in about gh. 55¢m. on an axis inclined about 263° to the
perpendicular to Saturn’s orbit-plane. The rings and all
the satellites, except the outermost, travel nearly in the
plane of Saturn’s equator, but the outermost satellite travels
on a path inclined about 15° to that plane.

Even on a general survey, only, of this wonderful system,
the impression conveyed to the mind would not be that we
have in Saturn an orb belonging to the same order as our
earth, were it not for the influence of the preconceptions to
which I have already adverted. It seems to me that if we
could imagine a visitant from outer space viewing our solar
system, he would at once recognise in Jupiter and- Saturn
the members of an order of orbs probably intermediate in
character between the sun and the minor planets. He would
reason that while, on the one hand, these planets being very
much less than the sun in volume and mass, are obviously
of an inferior order, and in this sense resemble the earth and
Venus; they are, on the other hand, sofar comparable with
the sun, even in these respects, that they largely exceed the
earth and her fellow planets—that is, in those circum-
stances in which alone the major planets are comparable
with the minor planets, they are as far removed from them
on the one hand as from the sun on the other. But when
we turn to features in which the major planets resemble the
sun, we find that they differ absolutely from the minor
planets. Thus, in having the complete control of systems

1874.] The Saturnian System. 13

of bodies, these planets resemble the sun, and are utterly
unlike the earth. In mean density Jupiter is almost exactly
like the sun, and Saturn has even a less mean density than
the earth. This last is the most important distin¢tion of
all, as we shall presently see ; in faét, I think I shall be able
to show that of itself it demonstrates the fact that the major
planets are utterly unlike the earth and her fellow minor
planets. Again, in the condition and phenomena of their
atmospheric envelopes, Jupiter and Saturn to a certain
degree resemble the sun, as will presently appear; and
though the resemblance is not altogether complete, yet this
is counterbalanced by the circumstance that the want of
resemblance between the major and minor planets in this
respect is very marked indeed.

It will be understood that I rely in the main for evidence
as to the condition of the atmosphere of Jupiter and Saturn
on the results of telescopic researches. Other evidence
there is, and in particular the spectroscope has afforded
information of an interesting nature. But as yet this infor-
mation is not definite enough to be reliable as a basis of
reasoning; whereas the evidence given by the telescope is
sufficient, rightly used, to convey very important information.
I would note that we may properly combine the information
given by both Jupiter and Saturn, since these planets
manifestly resemble each other in those leading features
which we can alone deal with in our present enquiries. It
is altogether likely that in minor respeCts Jupiter and
Saturn are as unlike as the earth and Mars. But precisely
as we can trace a general resemblance between all the
members of the minor family of planets, so manifestly
Saturn and Jupiter (as also probably Uranus and Neptune)
resemble each other in the broader features of their con-
dition. It is very important to recognise this, because, in
point of fact, the information conveyed by one planet
supplements in an interesting way that given by the other.
Jupiter being very much larger and far nearer to the earth
can be more satisfactorily studied; and we can only recognise,
in the case of Jupiter, the details of those atmospheric belts
which girdle both planets. But on the other hand Saturn
affords a test as to the nature of these belts, which is
wanting in the case of the larger planet. For Jupiter’s
equator plane is very little inclined to the level in which the
planet travels, whereas, as has been mentioned in the
elements given above, the equator plane of Saturn is
inclined at a very considerable angle, so that what we
may for convenience term the seasonal changes of Saturn

14 The Saturnian System. (January,

(noting always, however, that they must be quite unlike the
seasons of our earth) are of a marked character, whereas
Jupiter has scarcely any seasonal changes at all. Here,
then, is a criterion to show what part, if any, the sun plays
in producing changes in the condition of the atmospheric
envelopes of these planets, since we should expect, if his
action is the leading cause of changes, that the changes in
the Jovian belts would differ°markedly in charaéter from
those in the Saturnian belts.

I take for granted the ordinarily described telescopic
features of the belts, as presumably known to all the readers
of this Journal.

The first feature to be noticed as bearing on the condition
of the atmospheres of Jupiter and Saturn, is the remarkable
parallelism of the belts. It has been commonly stated that
this feature is comparable with the existence of trade-wind
zones on our earth. I apprehend that if our earth were
viewed from Venus or Mercury, even with high telescopic
power, nothing like zones would be recognised. It is,
indeed, only over the oceans that the equatorial cloud band
exists; and even this is but a mid-day phenomenon. The
sun rises in a clear sky in equatorial regions at sea; and it
is only towards noon that heavy clouds cover the whole sky.
In the afternoon these are dissipated by heavy rain-falls and
electric storms, and towards sunset the sky is clear.

There is, indeed, a difficulty in accounting for the zones
in the atmospheres of Jupiter and Saturn. Their ordinary
regularity implies the existence of a much more effective
cause than that which produces our trade-winds. The
cause must be, it should seem, a difference of rotational
velocity, causing clouds to lag as clouds on our trade zones
do, only much more markedly, or else causing clouds to be
carried in advance of the prevailing rotation-rate. Either
cause would serve equally well; the difficulty lies in under
standing how either can operate with sufficient activity.
The rapid rotation-rates of Jupiter and Saturn would of
course make the differences of rate correspondingly great.
But so far as the cause which produces our own trade-winds
is concerned, this circumstance is much more than counter-
balanced by the greatly reduced effects of solar action in
Jupiter and Saturn. That, notwithstanding this reduction
of effect, sun-raised clouds should be so much more ener-
getically swayed into zones than on our earth must be
regarded as altogether improbable. We must find some
other interpretation of these zones,—a result which would
indeed have been forced upon us, as I think, by the mere

1874.] The Saturnian System. 15

circumstance that there are sometimes so many of them.
Polar and equatorial air-currents such as exist in our own
air would naturally explain, perhaps, an equatorial cloud-
zone and sub-tropical trade zones on either side of it; but
they can afford no explanation of the existence, even though
occasional only, of three or four well-marked zones on either
side of the equatorial one.

_It appears to me a natural inference from these considera-
tions that the difference of rotational velocity to which the
cloud zones of Jupiter are certainly due, does not result
from polar and equatorial currents carrying cloud-matter to
regions where the movement of rotation is greater or less,
but from upward and downward motions within the Jovian and
Saturnian atmospheres. Or else, (though the assumption is
not incompatible with the hypothesis of upward and down-
ward currents), we may assume that some cause resembling
that which occasions the solar spot zones is at work to
produce cloud-zones on Saturn and Jupiter. We cannot
proceed much farther in this direction until we have more
definite information. But it suffices for our purpose to
notice that we have in upward and downward currents,
combined probably with some resemblance in condition to
the sun, a reasonable explanation of the general features of
the cloud-zones of the giant planets.

Only, it is necessary to notice that such views require the
atmospheric envelopes of these planets to be exceedingly
deep, and the upward and downward motions taking place
within them exceedingly rapid. The upward motions
would, in fact, appear, according to this view, to resemble
rather the uprush of vapours during volcanic eruptions than
any ordinary forms of vertical currents. The downward
motions need not necessarily be so rapid; they might, and
probably would, be merely the quiet return of the vapourous
masses which had been propelled upwards, by which they
resumed the level due to their density.

It appears to me that the results of telescopic scrutiny
correspond well with these requirements. It is impossible
to observe the belts of Jupiter with adequate telescopic
power without being led to the conviction that the atmo-
sphere in which these belts exist is exceedingly deep. It is
impossible to convey by any description, and not easy to
indicate even by pictorial illustration, the force of the
telescopic evidence. It may be remarked, however, that
the shapes and changes of shape of the cloud masses show
that they have been generated in a deep atmosphere, and
therein exposed to modifying influences. There is also one

16 The Saturnian System. (January,

piece of evidence on this point the significance of which is
unmistakable. Scarcely ever, if ever, is any feature stable,
even for a few successive rotations. It is certain that we
scarcely ever, if ever, see the real surface of Jupiter or
Saturn. I doubt myself whether those features whose suc-
cessive returns have been observed for the determination of
the rotation-rates of these planets are other than atmo-
spheric phenomena. They appear to resemble rather the
solar spots, whose motion may indeed suffice for the deter-
mination of the general rotation-rate, but cannot possibly be
regarded as the motion of some obje¢t on the real surface of
the solar orb (if he have any). However this be, it is
certain that if any part of the real surface of Jupiter has
ever been seen, the whole of that surface is usually con-
cealed from view. Even the dark zones are not zones of
his real surface, though they unquestionably underlie the
bright cloud zones. Moreover, signs of violent action
-such as I have suggested have been by no means wanting ;
since not only do the features of the Jovian belts change
rapidly in shape, but special details are sometimes seen,—as
round white spots lasting but for a short period, &c.,—which
can be readily explained as due to an uprush of vapour,
and, in my opinion, can no otherwise be so satisfactorily
accounted for.

But so soon as we admit the probability that the atmo-
spheres of Jupiter and Saturn are very deep, we are led toa
line of reasoning which seems demonstrative of the fact
that the condition of these planets is utterly unlike that of
the earth. A deep atmosphere, subjected to the strong
gravitating energy of either planet, would acquire at ordi-
nary temperatures a density altogether incompatible with
the existence of any resemblance to our own atmosphere in
any part of its extent. In fact, if we only assume that the
atmosphere of Jupiter has a depth of 50 miles below
the cloud layers, we deduce at the surface of Jupiter
a density incompatible with the gaseous state, a density
exceeding many times that of our heaviest metals! It is
difficult to suppose that that atmosphere, the changes in
which are so manifest at our great distance from the giant
planets, has a less depth than this would imply; and yet
the assumption that it has such a depth leads dire¢tly to the
conclusion that (if at ordinary temperature) it increases in
density till liquefaction is attained, and that if Jupiter has
any liquid surface at all, such surface is due to the pressure
of the Jovian atmosphere producing liquefaction. There
would, however, be more probably continuity of change

1874.) The Saturnian System. 17

from the vapourous to the liquid condition. I do not say
that this is the actual state of matters; on the contrary, I
shall endeavour to show that the real condition of the
Saturnian and Jovian atmospheres is altogether different.
But this is the conclusion to which we are led if we assume
that these atmospheres have such a depth as telescopic
observation indicates, and exist at ordinary temperatures.
But if we assume, as we must on the assumption of ordi-
nary temperature, that, at a comparatively moderate depth
below the apparent limits of the globes of Saturn and
Jupiter, the liquid condition is attained by mere vastness of
atmospheric pressure, or else exists simply because the
atmosphere is not so deep as we have been supposing, we
have, in the small mean densities of Jupiter and Saturn, a
problem of no ordinary difficulty... We cannot possibly
believe (in the presence of the results experimentally shown
to follow from applying great pressure to solid materials)
that there can be cavernous openings in the interior of
these vast globes. Under enormous pressure, solids, even
such solids as iron, gold, and platinum, are perfectly plastic.
They vun like fluids. And no pressure ever yet applied
experimentally is for a moment comparable with the pressure
which must exist at very moderate depths below the surface
of Jupiter and Saturn. It is as incredible that cavernous
openings or great hollow interiors exist in the solid globes of
Saturn and Jupiter as it would be that cavernous openings
should exist in the depths of ocean, and with no other walls
but the water itself. If the globes of Saturn and Jupiter
are in the main solid or liquid, they are solid or liquid
throughout, without gaps or interstices. Moreover, they are
subject to a pressure constantly increasing from surface to
centre, and enormously greater than that at the earth’s
centre, at but a relatively short distance from the surface.
In Jupiter especially, the pressure must increase with great
rapidity, on account of the greatness of his attractive power;
for gravity at his surface exceeds gravity at the earth’s
surface fully 2} times. And again, in Jupiter’s enormous
globe, a depth such as that which separates the centre of
the earth from her surface is relatively insignificant, being
less than a tenth part of the distance separating his centre
from his surface, on our present assumptions. ‘That a solid
or liquid globe, subjected to such enormous pressures
throughout by far the greater part of its volume, should
have a mean density less than a fourth of the earth’s, as in
Jupiter’s case, or less than a seventh of the earth’s, as in
Saturn’s, must assuredly be regarded as a most surprising
VOL. IV. (N.S.) D

18 The Saturnian System. (January,

circumstance. Of what materials should such a globe be
composed? Are there any materials whatever, of such
small density, which can be supposed to exist in such rela-
tively enormous quantities as to constitute nearly the whole
of the mass of Jupiter or Saturn? It would be absurd to
regard as a reasonable hypothesis, now, either the theory of
Whewell, that Jupiter consists mainly of water, or the
alternative suggestion of Brewster, that the substance of
the giant planets may be of the nature of pumice-stone.
Such theories as these are the really startling theories
of science; they are really fanciful, because based on no
known physical fa¢éts. They were unscientific even when
they were propounded; but they are doubly unscientific
now that spectroscopic analysis has rendered it probable
that the elements constituting the great orbs of the universe
are in the main the same that we are familiar with on earth,
and proportioned similarly as to relative quantity. If our
sun were to solidify, there would be in his globe our familiar
iron, gold, copper, calcium, sodium, and other metallic
elements, combined with those other elements which we
recognise as the chief constituents of the earth’s globe.
We cannot refuse to admit the probability that what is true
of the small earth and the gigantic sun, as well as of his
giant brothers, the stars, can scarcely fail to be the case
with the intermediate order of bodies to which Saturn and
Jupiter belong. But we cannot admit this inference, pro-
bable theugh it is, if we adhere to our assumption that the
conditions of temperature in Saturn and Jupiter resemble
those in our earth. We should certainly find these planets,
in that case, as dense as our earth, or rather (considering
the much larger pressures to which the greater part of their
mass would be subjected) we should find their mean density
very much greater. Since, on the contrary, they are of
very small mean density compared with the earth, we are
driven from the assumption that their physical condition
resembles that of the earth.

It is natural, under these circumstances, to inquire
whether, since the earth gives us no satisfactory explana-
tion of the condition of Jupiter and Saturn, we may not
find in the sun some suggestions towards an explanation.
It would have been natural, indeed, to have turned first to
the sun, because of the much greater similarity of condition
already mentioned as existing between the giant planets and
the sun. But I preferred to consider first the less obvious
and probable line of argument, partly to dispose of it, and
partly because, unlikely and even unreasonable as it is, it is

1874.] The Saturnian System. 19

the one which has hitherto been nearly always followed.
Very few have thought of explaining Jovian and Saturnian
phenomena by a reference to solar phenomena; very
many, including believers as well as disbelievers in the
habitability of Saturn and Jupiter, have endeavoured to
force the observed phenomena into accordance with the
familiar phenomena of our own earth.

We notice at once that the same low density being recog-
nised in the case of the sun as we have been discussing in
the case of the giant planets, any explanation which presents
itself in the sun’s case is available, at least to be tested by
whatever evidence may exist.

Now we can have no hesitation in ascribing the sun’s
small mean density to the great temperature of his whole
globe. This temperature operates against those effects of
pressure which, in his case, would operate far more markedly
than in the case of the giant planets. Many elements,
which in his interior would be solidified or liquefied by the
great pressures to which they are subjected, remain gaseous,
and others which do not remain gaseous yet exist at a density
far lower than that which they would have if at ordinary
temperatures. We may say of the sun as a whole that its
globe is expanded, and so reduced in density by excess of
heat. We are not able to explain precisely how his various
elementary components are disposed throughout his globe
in consequence of the temperatures and pressures at which
they severally exist. In fact, everything in the sun is so
unlike what we are familiar with, that we cannot apply
directly any of the known laws of physics to the interpreta-
tion of solar phenomena. But we remain, nevertheless,
satisfied that the main reason why gravity has not its will
throughout the solar orb, compressing the substance of that
orb until a high mean density results, is that the great heat
of the sun opposes the process of contraction which would
operate at once if gravity were left unresisted.

The inference is that the orbs of Jupiter and Saturn are
in like manner intensely heated, though, it need hardly be
said, by no means to the same degree. Nor, in fact, can it
be necessary, to maintain the mean densities of Saturn and
Jupiter at their present low amount, that anything like the
same degree of heat should exist in their case as in the sun’s.
For the pressures due to gravity are far less even near the
surface of these planets, and the distance from surface to
centre, on which the amount of the increase of pressure
beneath the surface depends, is very much less. But that
the temperature of Saturn and Jupiter greatly exceeds that

The Saturnian System. [January,

which exists in the case of our own earth, seems to be the
explanation to which we are driven by the facts of the case,
and, from what we know of the sun, may be regarded as
a sufficient explanation.

It remains to be seen, however, whether this explanation
is supported or negatived by other facts. If it be the correct
explanation, moreover, not only should it be in accordance
with the facts hitherto considered, but it should indicate the
existence of other relations than those which have led us to
it. In other words, on carefully considering this theory,
consequences should appear to follow from it which corre-
spond with the actual results of observation.

Let us begin, however, by considering the arguments which
at a first view seem to oppose the theory that the globes of
Saturn and Jupiter are intensely heated.

It is manifest that the heat required by the theory is such
that the substance of the real globes of Saturn and Jupiter
must be self-luminous, and perhaps to a high degree. Now
it is certain that the discs of these planets, as we see them,
do not owe their light chiefly to inherent luminosity. This
is shown, not only by what I shall mention presently as to
the quantity of light received from these planets, but also
by a circumstance which deserves more careful attention
than it has yet, I think, received. Not only does the disc
grow darker near the edge,* as it would if the light were
reflected light, but both Jupiter and Saturn, when near their
quadratures, show a marked defalcation of light on the side
where lies the terminator of the really gibbous disc. Again,
we see that the satellites of Jupiter disappear in the shadow
of their primary, which would not be the case if the planet
shone with a very strong inherent light. An even clearer
argument at a first view is found in the circumstance that
the shadows of the satellites look black, as though the whole
of Jupiter’s light were reflected sunlight.

None of these circumstances, however, suffices to prove
that the disc of Jupiter does not possess some degree, and
even it may well be a considerable degree, of inherent
luminosity. It is manifest that the vanishing of the satel-
lites in Jupiter’s shadow would only imply that his disc
does not glow with an intense lustre of its own, a fa¢ét which
is otherwise obvious. The darkening at the edge of the

* To ordinary vision, the reverse appears the case; but the reason of this is
that the dark sky on which, as on a background, the disc is seen, causes the
edge of the disc to look dark by an effec of contrast. Mr. Browning tested
the matter two or three years ago with a graduated darkening-glass, and found

that, as had been theoretically inferred from the aspect of the satellites on
different parts of the disc, the edge is darker than the middle.

1874.] The Saturman System. aI

disc does not show that the light is im the main reflected,
though it proves that a considerable share of the planet’s
light is reflected. The apparent blackness of the satellites’
shadows would be a strong argument if we were not aware
how large a part contrast may play in producing such a
phenomenon. The spots on the sun look black at their
nucleus by contrast with the light of the photosphere, but
so does the glowing lime of the oxyhydrogen light look
black against the sun’s disc. And a like test is available to
show that the blackness of the shadows of Jupiter’s satel-
lites may be apparent only. For the satellites themselves
ordinarily look dark in transit, and the fourth satellite looks
absolutely black. Now this fourth satellite is certainly not
black ; in fact, it shines on the background of the sky with
a sufficiently bright light. We have, therefore, no evidence
that the inherent luminosity of Jupiter may not be equiva-
lent to the light which the fourth satellite reflects.

Now it is to be noticed that the light of matter glowing
with intensity of heat is not necessarily intense. The red
of burning coals, for example, or of hot metal is not so
bright as many imagine. It is not so bright as a red object
in ordinary sunlight. The very best imitation of a fire of
glowing coals I ever remember to have seen was produced
by a piece of rather dark red cloth, accidentally placed ina
grate in an ill-lighted room (day-light). Bright red cloth in
sunlight does not produce nearly so good an illusion; and
it is perhaps hardly necessary to remark that the ordinary
imitations of a coal-fire in theatrical representations fail in
consequence of their being very much too bright.

In my opinion, there is nothing to prevent us from
assuming that the darker belts of Jupiter owe the ruddiness
of their colour to the glow of a red-hot interior, and this
extends to the case of Saturn, whose dark belts bear
a tolerably close resemblance to those of Jupiter in their
general tint. I would not have it thought, however, that I
limit the inherent heat of Jupiter to ordinary red heat.
I simply infer that the portion of the inherent light which
makes its way through the cloud-laden envelope of the
dark belts corresponds to that of red-hot matter. I should
regard the brighter belts, notwithstanding their greater
brightness, as those whence less inherent luminosity
proceeds, the greater part of their light being, I conceive,
reflected from clouds of purest white, concealing the glowing
surface beneath. It is to be carefully noted, however, that
we have no reason for believing that any part of the cloud-
belts of either planet is absolutely continuous. Openings

22 The Saturnian System. (January,

two or three hundred miles across would be quite invisible
from the earth with the best telescopes and the most piercing
eye-sight. In faé¢t, the apparent area of such openings in
Jupiter’s atmosphere would be less than the fiftieth part of
the least of Jupiter’s satellites.

All that we might expect, I think, as an effect of the
high temperature which our theory requires in the giant
planets, is that these globes should shine with a light
notably brighter than globes of equal size, similarly placed,
and constituted of some such substance as the whiter kinds
of sandstone. Now this is certainly the case. The lowest
estimates of the brightness of Jupiter and Saturn assign to
these orbs regarded as absolutely opaque a reflective power
more than twice as great as that of white sandstone.
Jupiter’s brightness, as a whole, is not far inferior to that
which he would have if his whole surface were of the white-
ness of driven snow. When we remember how far his
globe is from being white, its actual whiteness as a whole
resulting from the combination of several colours, we see
that, according to this the lowest estimate, he must possess
some inherent lustre. But other estimates have placed his
brightness far higher. And it is a notable circumstance
that Dr. De la Rue, in photographing Jupiter and our moon
under the same circumstances (atmospheric and otherwise),
found that the actinic power of the moon is to Jupiter’s
only as 6 to 5, or 6 to 4, whereas if the two bodies both
shone only by refleCting solar light, and possessed equal
reflective powers, the moon should have nearly 27 times the
actinic power of Jupiter, since Jupiter is 5; times further
from the sun than the moon is. ‘‘ On December 7, 1857,
Jupiter was photographed in 5 seconds, and Saturn in 60,
and on another occasion the moon and Saturn were photo-
graphed in 15 seconds, just after an occultation of the
planet.” Jupiter should exceed Saturn about four times if
both shone by reflecting solar light, and Saturn would
appear, from the observation of December 7, 1857, to be of
a brightness inferior to that due to its greater distance,
while the other observation would imply the reverse. It
seems manifest that photographic results would require
a careful comparison, not only inter se but with some standard,
to lead to satisfa¢tory conclusions.

We may place greater reliance on direct photometric
estimates; and, as it seems to me, the following results by
Zollner, when carefully studied, indicate that the condition
of the outer planets differs essentially from that of the earth,
Mars, Moon, and probably Venus and Mercury. He found

1874.] The Saturnian System. 23

the light of the following planets, regarded as light-reflecting
bodies, indicated the tabulated reflecting powers :—

Monte acs sls a6 6. i, (CO L720
Marss (Sis say es Or 2072
(pILSEa-! cape 2 e) O10Z36
Satu: .- w4,” us. | 3 MOMOSE
Uranus 7s). Ve) 0<) ay 5. “OO700
Neptine Wis ss - a Ort04G7

The following determinations of the reflecting powers of
terrestrial substances indicate the significance of Zollner’s
results :—

Snow just fallen . . . 0°783
White paper << =. « (0°700
White sandstone . . . 0°237
lag Mae si, eo pis ts ate Y O'L5O
Ouartz porphyty =. « o-108
MOISE. SOM: 4s. oe @ +o). 07079
Dark erey syenite.. . . o078

I have discussed at some length and in various aspects,
in my ‘‘ Other Worlds” and Essays on Astronomy, the
evidence in favour of occasional actual change in the shape
of Saturn. It seems to me that it may now be desirable to
quote the ipsissima verba of Sir W. Herschel as to the so-
called square-shouldered aspect of Saturn. It must be
mentioned in the first place that no possible question can
now exist as to the ordinary shape of Saturn’s disc being
that of an ellipse. Herschel himself was not quite sure
whether the square-shouldered aspect might not have been
presented even when he made those earlier measurements
which seemed to indicate a truly elliptical figure. But as we
now know from the measurements of Main, Bessel, and
others that the ordinary figure of Saturn is elliptical, we see
what interpretation can alone be placed on the observations
now to be quoted, if accepted.

It is customary to assign April, 1805, as the first occasion
on which Herschel perceived any departure from the
elliptical figure. But he himself quotes the following
observation, made 17 years earlier :—

* I may note, by the way, that, considering the enormous difficulty of
determining the dimensions of the planet Neptune, it may be questioned
whether the above result might not suggest that the real dimensions of
Neptune are less than usually stated, and therefore the albedo greater than
above indicated. Of course it would be extremely rash to assume this on the
strength merely of the fa& that Neptune has a less albedo than any of his
fellows among the giant planets. Still the point is worth noting.

24 The Saturnian System. (January,

** August 2,1788, 21h.58m. 20-feet reflector; power 300.
—Admitting the equatorial diameter of Saturn to lie in the
direction of the ring, the planet is evidently flattened at the
poles. I have often before, and again this evening, sup-
posed the shape of Saturn not to be spheroidical (like that
of Mars and Jupiter), but much flattened at the poles, and
also a very little flattened at the equator; but this wants
more exact observations.”

The results observed in 1805 have been often quoted by
myself and others. It appears, therefore, desirable to
proceed to the results obtained in 1806 :—

** April 16, 1806.—I examined the figure of the body of
Saturn with the 7 and tro-feet telescopes, but they acted
very indifferently ; and, were I to judge by present appear-
ances, I should suppose the planet to have undergone a con-
siderable change. Should this be the case, it will then be
necessary to trace out the cause of such alterations.”

‘‘April 1g. s10-feet; power 300.—The polar regions are
much flattened. The figure of the planet differs a little
from what it appeared last year. ‘This may be owing to the
increased opening of the ring, which in four places obstructs
now the view of the curvature in a higher latitude than it
did last year. The equatorial regions, on the contrary, are
more exposed to view than they have been for some time

ASE.

Then follow several observations indicating a close
resemblance in 1806 to the figure which the planet had
presented in 1805, when the flattening was first recognised.
At length we have :—

“‘May g. Power 527.—The air being very clear, I see
the figure of Saturn nearly the same as last year; the flat-
tening at the poles appears at present somewhat less; the
equatorial and other regions are still the same.”

These observations, combined with those made in 1805,
and with subsequent observations by Schroter, Kitchener,
Sir John Herschel, Coolidge, the Bonds, Airy, and others,
seem to leave little doubt as to the occasional apparent ex-
pansion of the planet in its temperate zones, and also as to
other changes of figure sometimes limited to one hemisphere
of the planet’s globe.

I find it difficult to understand how these observations,
made, be it observed, by experienced astronomers, can be
explained as due to illusion. They accord perfectly well
with the theory which I have advocated in the present essay
and elsewhere. I would not indeed suggest that owing to
any processes of expansion or contraction changes take

1874.] The Saturnian System. 25

place in the real globe of Saturn, or even that his atmo-
sphere becomes at times heaped up in particular regions;
but there is nothing to prevent the occasional existence
(perhaps for long periods of time) of cloud-layers at higher
levels than usual in the temperate zones, or else the occa-
sional dissipation of the higher cloud-layers in the equatorial
zone.

I have described, in my ‘‘ Other Worlds,” an observation
of the ingress of one of Jupiter’s satellites on the disc, and
its subsequent reappearance, as though tt had retraced tts course ;
and I have shown that the only conceivable explanation of
this remarkable phenomenon (witnessed by three excellent
observers at different stations) appears to reside in the rapid
dissipation of a high cloud-layer. I have never seen any
other explanation even suggested; and, for my own part, I
cannot agree with those who would simply abandon all
attempt at explanation.

The general conclusion to which all the evidence, as it
seems to me, would appear to point, is that both Jupiter
and Saturn are in a semi-sun-like condition. It is not alto-
gether correct to say that they occupy a position midway
between that of the earth and that of the sun, for, in point
of fact, such a mode of expression does not*admit of any
definite interpretation. It is manifest, moreover, that in
some respects Jupiter and Saturn are utterly unlike the sun,
while in other respects they are utterly unlike the earth and
her fellow terrestrial planets. ‘They must be regarded as
sui generis; and it must be the work of long and careful
observation with the best telescopes to ascertain the nature
of these orbs. This is a subject of independent research,
and although some analogies suggested by our knowledge of
the earth, and other analogies suggested by our knowledge
of solar phenomena, may be useful as guides, yet, on the
whole, the safest course will be to pursue the inquiry in an
independent manner. And here I would note that there is
excellent promise of new information to be derived from the
systematic observation of Saturn and Jupiter in both hemi-
spheres of the earth.* Hitherto most of the observations

* It would not, indeed, be necessary that northern and southern observatories
should be engaged in the work if an observatory could be established, for
researches into the physics of astronomy, in some elevated region of our pos-
sessions in British India. For, near the equator, the ecliptic at all times
passes high above the horizon. It was proposed some time since, by
an almost unanimous vote of the council of the Astronomical Society, that
such an observatory should be erected for the purpose indicated. Whether
this proposal will be carried out remains to be seen. It unfortunately was
made only as arr amendment on a proposition of an eminently unsatisfactory

VOL. IV. (N.S.) E

26 The Saturnian System. (January,

have been made in the northern hemisphere, though even
there systematic observations have been wanting. Now
Jupiter for six years and Saturn for fifteen years lie to the
south of the equator, and are therefore ill-placed for obser-
vation from northern stations. It may well be that changes
occur having as their period the year of either planet, in
which case observations made during one half only of the
year of either planet cannot reveal the law or nature of
such periodic changes. And in any case it must needs be
unsatisfactory that trustworthy observations should be
interrupted for periods so long as those I have named.

A similar consideration applies to the Saturnian rings.
It seems to me to have been demonstrated that these rings
consist of multitudes of discrete bodies, though whether
these be solid, fluid, or vapourous remains uncertain.
Observations of both sides of the ring-system are much
required, however, to elucidate the whole subject of the
constitution of these strange objects. Now hitherto only
the northern side of the system has been satisfactorily
examined ; and this side is only presented towards us under
conditions favourable for study during two or three succes-
Sive oppositions out of the whole series of oppositions
occurring during a Saturnian year. It is worthy of remark
that all the chief discoveries respecting the rings have been
made at these times. It cannot but be regarded as most
desirable that the opportunities afforded when the ring
is most open, but the southern side turned earthwards,
should not be lost. If, as is supposed, the ring-system
is undergoing processes of change, systematic observations
at these favourable times are essential to the inquiry into
their condition.

nature, brought forward by Colonel Strange; and it is to be feared that it may
not be received with such favour in Government circles as it would perhaps
have obtained if not foundin questionable company. Nevertheless it is in itself
an excellent proposition, and, supported as it was by all the leading members
of the council except one, it is difficult to imagine that Government would
refuse a favourable hearing to it. Should it ever be carried out, we can
scarcely doubt that the physics of astronomy would be importantly advanced,
and results obtained which at present are unattainable owing to the limited
range of our northern observatories.

1874.] Refracted and Diffracted Spectra. 27

II. ON THE RELATION BETWEEN REFRACTED
AND DIFFRACTED SPECTRA.

By Munco Ponrton, F.R.S.E.

O all workers with the spectroscope, an accurate
method of determining the relation between the
indications of that instrument and the normal

positions of the spectral lines in the diffracted spectrum,
which correspond to their wave lengths, has long been an
object of desire.

The method hitherto followed, in ascertaining the wave-
length corresponding to any line found in the field of the
spectroscope, is that of interpolation, by means of the
formula suggested by Mr. W. Gibbs, in ‘‘Silliman’s Journal,”
for July, 1870. Reduced to its most simple shape, this
formula may be stated thus :—Let a, b, c represent the
given positions of any three lines in the index of the spe¢tro-
scope, and let x, y, z represent their corresponding wave-
lengths. Further make 6—a=/, c—b=q, and c—a=r.
Then, according to the formula of Mr. Gibbs, we have—

he Bali
2 ts ae G
from which any one member may be found if the rest are

given.

This formula, however, is applicable only when the three
lines are very near each other—a proximity not always
attainable. Moreover, it will be found that, even when the
three lines are near, the result is much less approximately
correct in some parts of the spectrum than in others.

The truth is, that the formula is absolutely correct only
when thrown into the following more general shape—

e Pigt Ee — 0)

ze me oe

where the exponent « is variable, having diverse values in
different parts of the spectrum.

The question thus arises, whether it may be possible to
ascertain the law, according to which this exponent varies,
with sufficient accuracy to render the formula available, not
only for determining unknown wave-lengths, but also for
correcting those already approximately ascertained by obser-
vation. Could implicit reliance be placed on an adequate
number of observations, this task would not be difficult.

28 Refracted and Diffracted Spectra. (January,

At present, however, the observations are neither so
numerous nor so correct as to admit of the determination
of the law with perfect accuracy. It is nevertheless possible,
by taking advantage of the observations as they exist, to
determine the manner in which the exponent varies with
such a degree of correctness as may be found available for
practical purposes.

The following investigation has been based on a care-

ful comparison of Angstrém’s Atlas of the Diffracted
Spectrum, and his Relative Tables of Wave-lengths, with
the Maps and Indices of the Refracted Spectrum, by
Kirchhoff, Hofmann, Angstrom, and Thalén.

To find the value of the exponent « for any three lines, of
which both the positions in the index of the spectroscope
and the corresponding wave-lengths are approximately
ascertained by observation, is a little troublesome; because
it can be done only by the method of gradual approximation,
or trial and error. It therefore becomes of importance to
have the value of « determined and tabulated for every
1o° of Kirchhoff’s scale; because the value of « being known,
the calculation of the wave-length from the general formula
becomes easy. Such a table must proceed on the assumption
that the vate of variation of the value of e remains nearly
uniform for 10° of Kirchhoff’s scale; and although this
assumption cannot be said to be absolutely correct for every
Io’, yet it is so nearly accurate as to be practically available.

For the purpose of framing such a table, it is convenient
to assume the extreme lines A, and the more refrangible H
of the speétrum as constants; so that, in the formula, the
quantities x, z, and y may be always the same. ‘Then if 0,
the index position in the spectroscope of any line, be given,
its corresponding wave-length y may be found by means of
the tabular value of « in the region where 0 is situated. It
is further convenient to assume the value of z to be 10, and
to determine the wave-lengths, in the first place, in relation
to this basis, converting them afterwards into the millimetric
scale of Angstrém. By this method we have always
e=log. x, which is a facility in calculation.

The assumed position of Ain Kirchhoff’s scale is 404°5,
and of the more refrangible H 3882'5, the difference being
3478=r in the formula. Then the value of p is always
= b—404'5, and that of g=3882°5—b. The log. of the wave-
length x in relation to z is 1°2863197, and the log. of that
log. is 0*1093490, which is one of the constants in the
calculation. ‘The log. of y is 3°5413296, and is another

{
|
,
|

a es “So

1874.] Refracted and Diffracted Spectra. 29
constant. The log. by which the relative wave-length y
found by the calculation, is converted into the millimetric

scale’of Angstrom is 2°5947234.

The following are the values of e for the six principal lines
of the spectrum, intervening between A and the more
refrangible H, based on their positions in Kirchhoff’s index,
and the formulated values of their wave-lengths relatively
to that of H=1o.

Index position. Log. of wave-length. Log. of log. Value of «.
Bs)! 2593°r I°2420499 0°0941391 3°1516
G50 69455 1°2223188 0°0871845 3°1963
iD ro02;8 1°1757690 0°0703210 372322
E. 1523°7 1°1269776 0°0519153 3°0057
F. 2080'0 T°0919797 0°0382145 2°6244
G. 2854°4 1°0394751 o’o168141 3°3636

From the last column it will be perceived how variable is
the value of «, and how erroneous must be any formula
which is based on the assumption of its being constant—
more especially if the constant be fixed so low as 2.

The annexed table of the value of « has been calculated
for every 10° of Kirchhoff’s scale, for the entire space
between B and H. In the space between A and B, the
observations are so few and uncertain that it has been
found impossible to extend the table into this region with
any degree of satisfaction.

A careful examination of this table will show that, were
the values of « graphically represented, they would form not
a continuous curve, but a waved line—although in certain
parts the line becomes straight. From 590 to rooo of
Kirchhoff’s scale, the value of « gradually rises from 3°1516
to 3'2342; but there isa slight interruption to the continuity
of the ascent at 830 of the scale, where it has attained to
3°2130. Here it remains constant for 5 terms, after which
it falls slightly, becoming at 880 only 3'2040. It then
ascends until, at 930, it reaches 3°2310, from which point
there is a second fall, until at g60 it becomes 3°2210, whence
it ascends to the maximum of 3'2342, which it reaches at
1000 of the scale.

From this maximum there is a continuous and more or
less regular descent, until at 1980 of the scale the value of
e is reduced to its minimum of 2°6150. From this point
there is a continuous ascent to a second maximum at 3526,
where « reaches the value of 3°4520. In this interval there
are several points, at which « remains unaltered for several
successive terms of the series. From 3526 of the scale

30 Refracted and Diffracted Spectra. |January,

there is again a descent, which attains its lowest limit at
3770, where « is 2°9100. This value remains constant to
3820 of the scale, from which point there is a rapid ascent
to the end of the series; but in this part of the table the
values of « are somewhat uncertain.

In some parts of the series, the differences in ascending
or descending from term to term are pretty regular; while in
other parts these differences vary more abruptly. Their
general characteristic feature is an alternate rise and fall in
their value, so that, were they represented graphically, they
would exhibit a very wavy line, at intervals becoming
straight.

For this table, absolute accuracy is not claimed; but it is
as nearly correct as it can be made in the present imperfect
state of the observations. Future more accurate observa-
tions may render it necessary to introduce into it slight
modifications here and there; but it is far from probable
that these will affect its main features; while it may even
now be trusted in the calculation of the wave-lengths, which

will be correct to the fourth place of figures in Angstrom’s
millimetric scale.

To illustrate the method of applying the scale to this
purpose, let us take an example. Suppose we wish to
ascertain the wave-length corresponding to the hydrogen
line, which stands at 2796°7 of Kirchhoff’s scale. One
advantage of taking the extreme lines of the spectrum as
constants is, that it presents the general formula always in
one shape, namely—

i Y
€e=
Pd
ZE NE
where y is the wave-length to be found, and the other
quantities are all given.
In the case of the above hydrogen line, we have—
p=2796'7— 404°5=2392°2 log. 3°3787975

q= 3882'5— 2796°7=1085'8 ,, 3°0357498
y constant 3478°0 5, 3°5413296

The value of « corresponding to index 2800 is 3°2890
and to index 2790 3°2790

Difference 0’0100

so that 3'2790+67=3'2857 is the tabular value of «, cor-
responding to 2796°7 of index.

.

Refracted and Diffracted Spectra.

1874.]

K é
999 3°2330
1000 342
Io 270
20 200
30 131
40 064
50 000
60 3°1935
70 873
80 814
90 758
II00 704.
Io 652
20 601
30 551
40 502
50 454
60 407
70 361
80 316
go 272
1200 229
10 187
20 146
30 106
40 067
50 029
60 3°0992
79 955
80 919
go 883
1300 848
se) 813
20 Ta
3O% | 5/89
40 698
50 655

K £
1360 30611
70 568
80 527
go 487
1400 449
10 414
20 381
30 359
40 322
50 2098
60 280
a 270
90 260
1500 230
IO 170
20 0go
30 000
40 2'9910
50 820
60 729
70 636
80 541
go 445
1600 349
10 253
20 157
30 062
40 2°8968
50 875
60 783
70 692
80 602
go 513
1700 425
10 SY/
20 248

TAB EE.

K €
1730 2°8158
40 068
59 2°7977
60 886
79 795
80 704.
go 612
1800 519
10 427
20 337
30 249
40 164
50 o81
60 000
70 2'6917
80 834
go 749
Ig00 660
nfo) 570
20 480
30 399
40 310
50 240
60 Igo
70 160
80
a 150
2000 160
Io 170
20 180
30 Igo
40 200
50 210
60 221
70 232
80 244
90 300

K
2100
10

€
2°6380
460
559
640
720
800
880
979
2°7070
150
220
310
400
4990
540
5990
670
760
860
970
2°8070
140
200
270
349
410
490
600
720
830
920
999
2°g050
120
200
290
380

€

2°9475
579
670
779
850
930
3'0030
130
240
340
45°
559
660
780
890
990
3°1070
150
260
379
480
600
720
830
940
3°2060
180
290
390
490
600
700
799
890
3°3010
160
349

K é
2840 3°3500
50 614
60 to }
2900 f 664
10 to
40 } 680
2950 710
60 750
70 780
80 |}
oo pe) 88
3000 820
Io 860
20 880
30
40 } 890
5° 950
cae SoG
go 34
3100 o1o
Io 020
20 045
30 to
70 } 080
80 IIo
go 160
3200 Igo
roto 2
70 a
80 260
go to
3370 mip
80 280
go 290
eae 300
3470
80 304

K

3490

3500
Io

20
30
40

3°4319

324
330
380
450
520
440

3°0940
310
2°'9780
430
210

100

200
500
30100
3°1100
2600

4700

32 Refracted and Diffracted Spectra. (January,

To fina 2 —
log. £ 3°3787975
p € 3°2857
oe = 1'2390 Ae Sees
‘i 99°73 9°0930975
to find ze log. of log. x 0°1093490

log. of ¢ 0°5166279
log. xe 4°2264610 0°6259769

p
1239075 _~— log. g 3°0357948

Ze
log. x, above 4°2264610
4 =0'064466 teh 2 YB Bogs sae

—— log. r3°5413296
P4%— 17303541 log. o°1151247
ze XE ee BK
log. yé=3°4262049 log. 0°5348133
log. € 0°5166279
log. y =1°0427624 o°0181854
add constant 2°5947234

¥=4339°96 3°6374858

According to Angstrom, the value of this wave-
length.in the millimetric. scale is. . ... . « 4S4Ge

According to the above itis .° 2°. > 3.65. Se 4gapae

Difference 0000°14
which is almost unappreciable.

‘In judging of this result, it must be borne in mind that
the chances of errors of observation, in ascertaining the
wave-length and the position of the line in the scale of the
spectroscope, are about equal; so that, of the above dif-
ference, small as it is, only one-half should be set down to
the wave-length. If the latter be made 4340°03, thus
halving the difference, then with the exponent «=3°2857,
the position of the line in the scale of the spectroscope
would have to be made 2796'56, which differs only oo000°r4
from that assigned to it by observation—a difference which
is in like manner scarcely appreciable. As determined by
the table, then, this hydrogen line ought to have for its
index position 2796'56, and for its wave-length 4340°03.

1874.] Refracted and Diffracted Spectra. a3

The mode of finding the value of «, when both the position
of the line in the scale of the spectroscope and the wave-
length are given, and held to be absolutely exact, differs but
little from the foregoing. A certain value of « must be
assumed, and when log. yé and its log. are found as in
the preceding calculation, the log. of the log. of y, as given
by observation, is to be subtracted from it. If the value
of « has been accurately assumed, then the difference should
be exactly equal to log. «. If the difference be greater than
this last, then the assumed value of « must be increased ;
if the difference be less, then the value of e€ must be
diminished. A little experience will show the extent of the
requisite increase or diminution, which varies in different
regions of the spectrum.

Thus, in the foregoing case, if from the log.

2 NESE Gui aie ler ener ean, Semen

We subtract log. of log. of the relative wave-

length corresponding to 4340°1 of the milli-
MCESC HC oe Se cere a ping hs, oat, Sie ee ee OO OLOTOLE
UMMC Me? Sse ays Aye vias on alo 0°5166222
Myhich is less than log.'c by w ., 2... ..., 00000057

OD Ee ena tee Op LOO2 ZO

Thus showing that the value of e¢ should be slightly
diminished. The requisite diminution is 00015, making the
exact value of e, on the assumption that the observations
are absolutely correct, 3°2842.

It will hence be perceived how very sensitive is the expo-
nent, and how considerable a variation it may undergo even
with a scarcely appreciable difference of wave-length, or in
the position of the line in the spectroscopic scale.

In the table (p. 31), the columns marked K contain the
degrees in Kirchhoff’s scale; while those marked e contain
the corresponding values of the: variable exponent. The
table is submitted in the hope that, notwithstanding any
slight imperfections it may be found to contain, it may prove
useful to those who are engaged in spectroscopic investiga-
tions.

0°5348133

VOL. IV. (N.S.) F

34 Optical Phenomena of the Atmosphere. [January,

III. OBSERVATIONS ON THE OPTICAL
PHENOMENA OF THE ATMOSPHERE.

By S. BARBER, F.M.S..

qs) URING the first quarter of the year 1872, many
d— remarkable optical phenomena were observed in the

neighbourhood of Liverpool; and as I have on
previous occasions published remarks bearing on the
prognostic value of these appearances,* it seemed advisable
to colleét and compare such notes as may bear upon the
prediction of weather, and help to elucidate the questions
that have been raised as to the origin, and varieties of halos
and parhelia. The subject, certainly, is one of the highest
interest, both in relation to the various crystalline forms of
water and the constituent particles of the various forms of
cloud. A beam of light passing through the upper atmo-
sphere may reveal to us, by the laws of refraction, the
degree of congelation of vapour floating ten or twenty miles
away. The investigation of the cirrus and cirro-cumulus
being admittedly of the highest importance in relation to
the movements of the great atmospheric currents, it seems
surprising that the optical laws and phenomena bearing on
their constitution should not have received more attention
at the hands of meteorologists.

Before passing on to the proper subject of this paper—
viz., halos and parhelia—I may remark that the rainbow,
which appears to have been so thoroughly investigated,
exhibits at times more variety, both in form and colouring,
than most writers seem to be aware of. ‘These varieties
will be found—like those of the halo—to have a relation to
the general atmospheric conditions of the time. For example,
I have frequently noticed that the tendency to an irregular
outline, and the appearance of double bows, &c., are mostly
connected with stormy and squally weather. A dark day in
autumn, with low-flying nimbo-cumulus, and driving rain,
will sometimes exhibit, in its transient gleams of sunshine,
most curious and unexpected forms. On such occasions,
though the outlines are more remarkable, the colouring is
not so brilliant and decided as in calmer weather.

In the last “Quarterly Journal of the Meteorological
Society,” Mr. Scott gives notes of a double rainbow, with
reversed colours; and Mr. Lecky adds an account of a

* Quarterly Journal of Science, No. 26.

1874.] Optical Phenomena of the Atmosphere. 35

triple one produced by reflection from the surface of water—
seen of course in calm weather. I may add to these an
observation of a bow, which was almost devoid of colouring,
and divided into separate rings, four or five in number,
concentric, and decreasing in width towards the centre,* so
that the innermost was almost invisible. These rings were
near together; and the originating cloud seemed of low
altitude.

On another occasion I have observed a bow in which the
outline was decidedly broken and unsymmetrical. This was
also in the cumulus cloud, and in stormy weather.

I now pass on to the forms of halo and mock sun: two
of the latter were seen during the winter and spring of 1872.
The first was imperfect in definition, as seen from Aigburth,
about 434 miles south of Liverpool. This, though not a
brilliant form, is worthy of record from the fact of its
having been seen at stations widely distant from each other.
It was described in the ‘‘ Times,” as seen at Meath, in Ireland.
On comparing notes, I found that this description agreed in
several points with the observation made by myself. The
mock sun as it appeared near Liverpool was of an oval
‘form, and situated vertically over the real sun. It lay
at the point of contact of two arcs of halos tangent to each
other. There was no cloud in the sky, only a slight haze,
such as occurs after heavy dew and hoar-frost. This
occurred about g.10 on the morning of Jan. 22. There
had been a slight frost during the night.

The phenomenon having been observed at several places
some hundreds of miles apart, the originating crystals must
have been of unusual altitude and extent. In passing, I
may remark that the height of mock suns is probably very
inconstant. ‘Thus, in the cold weather of spring (1871), I
was fortunate enough to take an observation of the sudden
formation of a well defined ball of prismatic light, which
owed its existence to the passage of a rapidly moving
cumulus cloud. This could scarcely have been higher than
5 or 6 miles at the most. The mock sun was very similar,
both in form and position, to that described by me in the
““People’s Magazine” (February, 1872)—and it appeared
and disappeared with the cumulus cloud. The weather
changed to heavy rain on the day following the mock sun
oF jan, 22, 1872.

The next instance, of which I took more careful notice,

* The outer ring was about half the width of an ordinary rainbow, and
the inner ones became narrower by a fixed proportion.

36 Optical Phenomena of the Atmosphere. {January,

was visible from the Mersey, at Liverpool, from about 11.50
till 12.15 at noon, on Wednesday, April roth. (See sketch on
next page.) It seems to me to bea very unusual form. The
wind was nearly N. at the time, and the weather cold. As I
have ventured to maintain that halos and kindred optical
phenomena generally indicate a transitional state of the
temperature or of the weather, and not, as is popularly
supposed, an approaching storm, I draw attention to this
case aS an important, though by no means isolated, con-
firmation of the theory. it followed many days of wet,
and preceded about a week’s dry weather. On referring to
the sketch it will be seen that an arc of a halo attended the
mock suns (which were not very brilliant), and that the
chief peculiarity of the case lay in this—that the mock
suns were clearly external to the halo, and at a distance of
1° 30. or 2. The halo showed chiefly a red colour, and the
parhelia were entirely of a light prismatic blue, very distinct
from that of the surrounding sky.

Exactly a week after the last mentioned phenomena were
seen, a solar halo again occurred about I p.m., Wednesday,
April 17, and after this the weather grew warmer and the
sky still clearer. We shall probably not be justified in
expecting a decided change after every appearance of these
phenomena, for I have often observed that, in showery and
changeable weather, two or three solar halos of varying
degrees of definition will occur on successive days; but for
several years I have found that, when there is anything very
singular in the form or combinations of the circles, changes
of a decided character often follow.

Upon examining the recorded notices of these appearances,
we find that there are usually more accounts of lunar than
of solar halos, yet I have no doubt, from my own observa-
_ tions, that more solar halos really occur, and that most of
them are overlooked on account of the dazzling effect of
the sun’s rays, rendering their observations somewhat
troublesome to those who have not a strong eyesight. I
can safely say that in the neighbourhood of Liverpool they
greatly preponderate in number. Scarcely any change,
indeed, from wet to fair, as well as from fair to wet, occurs
without their appearance. Two more years’ observations
enable me to endorse the statement concerning their
prognostic value, which I published in spring, 1871.* I
desire now, however, to draw attention to two peculiarities
connected with the lunar halo which appear to be of very

* Nature, March 23, 1871.

1874.! Optical Phenomena of the Atmosphere. a7

evil portent. M. W. de Fonvielle, in commenting on an
appearance of very rare form of lunar halo, of which I had
sent an account to ‘‘ Nature” (Jan. 26, 1871), makes the
following remark :*—“‘ Il est presque inutile d’ajouter que
Vapparition de ce halo a été suivie, comme d’ordinaire, d’une
chate de neijes abondantes.” Of course this remark refers
to the winter season. I am not aware, however, that any
case is on record of a halo of go° appearing in the summer
time. Other similar cases of equal prognostic value have
since been observed. One of the most remarkable occurred
during the autumn of 1871.

This was a long horizontal band of light that proceeded
ina straight line from the moon to a distance equal to the
radius of an ordinary halo. At the point where this line
would have intersected the halo there were two short bands
of light passing through it vertically, so as to form a kind

IGE.

Parhelia. April, 1872.

of cross laid horizontally in the sky. Another phenomenon,
which, I imagine, has a kindred origin, was observed by me,
near Liverpool, on the Sunday before Easter, 1872. On
this occasion the cross was formed at the moon itself, and
the bands were only two or three degrees in length, at right
angles to each other. After these appearances I took
particular note of the weather. In a day or two, very
heavy rain set in, and continued for a long period. Students
of Meteorology will long remember the summer of 1872,
and it is remarkable that it should have begun with so
many and such unusual optical phenomena. This fact,
however, is particularly noteworthy—that after the great
electrical disturbance set in, and till the termination of the
storms, not a single instance of a well defined halo or any

* Comptes Rendus, Fevrier 27, 1871.

38 Optical Phenomena of the Atmosphere. [January,

cognate optical appearance was seen; and equally remark-
able was the absence during the same time of the cirrus
and cirro-cumulus forms of cloud. It would appear that
the amount of electricity diffused through the atmosphere
had some influence on the congelation of vapour, or that
the forms of cloud in question are in some way dependent
on an electrical condition, or a relation of the upper to the
lower stratum of vapour. During this season the electric
cumulus, of various forms and shapes, was the prevailing
cloud form.

Professor Poey, in his recently published remarks on
cloud classification, points out that, during the most
pronounced rain seasons, the two kinds of ‘“ pallium,”’—
viz., the high ice-pallium and the low mist-pallium—are
separated by a neutral region of the atmosphere, and that
the pallio-cirrus is then in a state of negative electrical
excitement, in common with the air at the surface of the
ground; while the pallio-cumulus and the rain that issues
from it are in positive electrical excitement; and that
electrical discharges continually take place between the two
concomitantly with the pouring down of wnelectrified rain
from the lower stratum upon the earth.

These results are singular and interesting, though it is to
be regretted, perhaps, that Prof. Poey has not given some
details of the means by which they were obtained. It has
seemed strange to me that the invention of atmospheric
electrometers and electroscopes, in combination with the
Captive balloon, has not been put to some praétical
use in the prediction of weather. By placing several of
these instruments at various altitudes, and synchronously
noting their indications, further important results may
perhaps be obtained.

On referring to Buchan’s “‘ Handy Book of Meteorology,”
I find acase of a halo intersected by twelve rectilinear bands
of light proceeding from the sun. No remark is made on
the origin of the bands; but experiment seems to show that
we must attribute these to reflection, and look for the cause
in the configuration of the terminating facets of the
suspended crystals. This theory is corroborated by the fact
that these bands of light are achromatic, which would not
be the case if they were caused by refraction.

A halo broken in its outline, and caused by well-defined
bands of linear cirrus, is, I believe, a more certain sign of
rain than a continuous circle. Another form that I have
noticed before bad weather is a fleecy and irregular circle,
wider in some parts than in others ; it is of a very evanescent

*
iit i i ie ne

1874.] Optical Phenomena of the Atmosphere. 39

character, and has but little colouring. This form, which is
very uncommon, appears sometimes when the sky is almost
clear.

A few notes on recent appearances of parhelia, in relation
to the attendant halos, may not be inappropriate. ‘The
sketch given of blue parhelia accompanying a red halo,
and clearly external to it, illustrates, I think, a very
uncommon case. It will also be seen that, while most mock
suns have an elliptical or oval outline, and the major axis in
a line with the circumference of the halo, the major axis of
this lay in a line with the vadius of the halo, and the balls of
light were not symmetrically placed.

Cases of parhelia without any halo are very rare. An
instance may be found recorded in “‘ Nature,” of an oval mock
sun entirely within the attendant circle, and _ situated
vertically above the real sun. Most of the cases of parhelia
noted by me have been in a horizontal line, not a vertical
one; and those situated above the sun have been very
deficient both in colouring and definition of form.

One remarkable feature of these appearances is this, that
when the parhelia are seen in very perfect form, the halo
that accompanies them appears only to show one colour,
and that generally red I believe ; whereas the ordinary solar
halo has blue for the most part predominant.

I now pass on to consider the various media, or conditions
of the atmosphere that give rise to these optical phenomena.
The form of cloud denominated by Howard cirro-stratus is,
as he himself remarked, the most frequent originator both
of lunar and solar halos; but ordinary cirrus also often
produces them in an imperfect form. The normal or
‘curling’ type of cirrus seldom shows prismatic tints,
though we know it to be stri€tly an ice-cloud ; nor does the
form of cumulus which we may call “snow cumulus.”
This seems strange when we consider that the halo is
simply a result of ice refraction; but it may be explained
upon the hypothesis that, in these two forms of clouds, the
particles are so massed together, and the prisms and crystals
so overlaid one upon another, that the refracted rays are
again combined and a white line produced, as may be seen
on a close inspection of a fresh snow-flake.

Taking, therefore, the various forms of cloud, we find
that halos are usually restricted to the following :—

I. Cirro-stratus, or as it is sometimes called linear
cirrus.

2. Ordinary cirrus. On this form I may remark, that it is
when somewhat thin and transparent that the halo appears.

40 British Artillery Matériel. [January,

It would be well, perhaps, to make distinction between the
kind of cirrus here alluded to and the whiter and denser
variety, which approaches in character to cirro-cumulus.
This variety is evidently a different composition, from the
fact of chromatic phenomena being absent. The surface is
whiter and less marked, and the outline more distinét than
in the halo-producing variety.

3. Club” cirrus. I thus denominate the long narrow
line of cloud which proceeds from a kind of tuft partaking
of the nature of cirrus and cirro-cumulus.

These are the commonest forms of cloud that produce halo.
We now take plain skies. I have observed the phenomenon
under the following conditions :—

1. A light greyish blue. This is very unusual.

2. A deep opaque blue. On this occasion the halo was
entirely red, as when the parhelia appeared.

3. High thin mist (probably floating crystals). This is
not uncommon in frosty weather. There is a general law
with regard to these phenomena which may be stated here,
viz-, that, “‘the clearer the sky the more perfect is the
colouring.” This I have verified by many cases. It may
also be added that the more defined the clouds of the upper
stratum, the less likely are halos to be seen.

IV. RECENT CHANGES IN BRITISH ARTILLERY
MATERIEL.

By S. P. OLIVER, Capt. R.A.
(Ce,

I. ap sth this year experiments have been carried out

24 both at Shoeburyness and on board H.M.S. Excellent

with some modified 24-pounder Hale’s rockets to

test their range, accuracy, and incendiary power in com-
parison with the ordinary service rockets, Mark III.

The modified rockets have the internal form of the cone
in the composition altered and a modified tail piece. These
alterations were expected to have the effect of greatly in-
creasing the velocity, duration, and rapidity of rotation,
ensuring greater range, greater accuracy, and less tendency
to puff. The modified rockets were found to be (with one
exception) all steady in flight, whilst all the service rockets
puffed more or less. ‘Those fired from the Excellent’s cutter
with Fisher’s rocket apparatus gave good results, with the

1874.] British Artillery Matériel. AI

exception of two, which burst prematurely in the air and
blew their heads off. Their incendiary power was tested as
follows:—Their heads were filled with Carcass (Valenciennes)
composition. Four rockets of each nature were firmly fixed
in a hole bored ina balk of timber, their heads protruding
and butting against another balk covered with inflammable
material. One of the rockets, after the composition had
burnt out, burst explosively, and blew the head to pieces
before the Carcass composition could be ignited. Mud was
heaped upon the heads of the others while the composition
was burning and the flame forced its way through; water
was also poured upon the heads without extinguishing the
flame.

Capt. Boys, R.N., considers that the incendiary powers of
the new modified rockets over those of the service are con-
siderably increased—that their range is rather better. The
deflection of both rockets is equally variable, the maximum
of service rockets being 100 yards, and that of the experi-
mental rocket 80 yards on either side of the target. The
Lords Commissioners of the Admiralty therefore consider
the modified rockets to be preferable for naval service; the
defect of premature explosion can easily be remedied.

II. The Electro-Ballistic experiments under Capt. Noble
have been continued, and tables have been arranged showing
the comparative probable rectangles of various ordnance,
and the greatest velocities obtainable by different guns.
The highest mean muzzle velocities obtained from the
g-pounder and 16-pounder rifled muzzle-loading guns, using
service common shells and service R. L. G. powder, were
found to be respectively 1562 and 1466 feet per second.

III. The report on the traversing arrangements are
satisfactory. After practice two men can easily traverse a
g-inch gun from right to left (arc about 110°) in 45 seconds.
Some of the g-inch platforms are being tried with traversing
gear on the spur- and mitre-wheel principle.

With regard to the recoil of guns, the Elswick com-
pressors have been found to work most satisfactorily, and
are to be retained where already fitted to 7 and g-inch gun
platforms.

IV. Important experiments and results have been carried
out and obtained by the Committee on gunpowder and other
explosives, especially as regards battery charges.

In determining the battery charge for any gun, the proper
course to be followed, in the opinion of the Committee, is
as follows :—To increase the charge gradually until disting
wave pressures are exhibited ; the highest charge which can

VOL. IV. (N.S.) G

42 British Artillery Matériel. {January,

be employed without these local pressures appearing should
then be accepted as the battering charge. Experience has
clearly demonstrated that, by limiting the charge in ac-
cordance with this rule, the maximum useful effect is attained
without any risk of undue pressures in the gun; and that if
the charge thus fixed is exceeded, a portion of the powder is
wasted, and the gun rendered liable to undue local pressures.
The charge of 85 lbs. of pebble powder exceeds that which
the above-mentioned rule would give for this gun, but to no
dangerous extent, although the maximum useful effect of
the charge is not obtained.

In determining the battering charge, a comparison between
the power of the gun with a calibre of 11 and 12 inches
came incidentally under the notice of the Committee; the
results of the experiments clearly demonstrated that a gun
of 145 inches length of bore is more powerful as a battering
weapon with a 12-inch calibre than with one of 11-inch,
and this is still more evident when it is considered that with
a 12-inch calibre the gun would probably consume 95 lbs. of
powder with as good useful effect per lb. of powder, and with
no greater pressure per square inch than it does 85 lbs. of
powder with an 11-inch calibre.

The detail has been published of various experiments
with 35-ton rifled muzzle-loading gun, No. 1. Shot, 700 lbs.

The pressures were determined by crushers fitted by
means of a copper cup at the bottom of the bore (A), bya
screw gauge inserted instead of the vent plug (B), and by
a gauge screwed into the base of the projectile (C). After
round 8 the gun was fired by an electric tube placed in the
cartridge at 12 inches from the bottom, the wires passing -
through a groove in the shot to the muzzle.

The following are a few of the points elicited by these ex-
periments, which appear of the greatest general interest :—

1. If the powder be burned uniformly in the gun, without
any indication of wave action, the pressure increases with
the increase of charge, at first rapidly, but after 20 tons on
the square inch has been exceeded, then very slowly. In the
whole course of the Committee’s experiments a uniform
pressure by crusher gauge of 30 tons in the powder chamber
has never been attained; this fact appears strongly to
corroborate the experiments carried out by Captain A. Noble,
at Elswick, on the pressure produced by ignited powder in
closed vessels, which indicated that the maximum pressure
produced by ignited powder in a perfectly closed space is
somewhat less than 40 tons to the square inch.

1874.] British Artillery Matériel. 43

2. When a charge of any description of powder is in-
creased beyond a certain limit, wave or local pressures are
set up which strain the gun unduly, without affording an
equivalent of useful effect on the projectile.

3. Provided the battering charge is not exceeded, the
pressure in the gun increases steadily with the increment
in weight of the projectile up to a certain point; beyond
this point no material increase of pressure can be obtained
by increasing the weight of the projectile.

4. Proof of pebble powder of Waltham Abbey and trade
manufacture in accordance with specification.

This proof has been carried on with the 8-inch smooth-
bored gun prepared for the purpose. The Committee con-
sider the results to be on the whole very satisfactory, and
express their unanimous opinion that the velocity and
pressure test of powder for heavy guns should never be
suspended, as they are satisfied it is the only proof that
will ensure the supply of powder good and uniform in
quality.

Considerable difficulties have been experienced, both at
Waltham Abbey and by the merchants, in keeping the
powder up to the specification; this might be reasonably
expected in the production of a newarticle. The Committee
consider themselves justified in saying that the progress
made is encouraging, most of the difficulties having been
overcome. Valuable knowledge is daily acquired, and light
thrown on many points by the system of proof adopted on
their recommendation.

V. Another explosive picric powder consists of only two
ingredients, saltpetre and picrate of ammonia, the in-
gredients being incorporated in the same way as those of
gunpowder.

The perfect stability of the two ingredients, per se, even if
exposed to degrees of heat very far beyond the extremes of
tropical temperatures, has long been fully established.

Picric powder is certainly not more susceptible of explo-
sion by fri¢étion or percussion than gunpowder.

Its exploding point has been compared in several ways
with that of gunpowder. In some instances the picric
powder exploded at a somewhat lower temperature, or
a little more readily, than gunpowder ; in others the reverse
was the case. The two substances may, therefore, be con-
sidered to have about the same exploding point.

Samples of picric powder, prepared early in 1870, which
have been exposed to light and preserved at ordinary atmo-
spheric temperatures, are perfectly unchanged.

44 British Artillery Matériel. (January,

Samples have been exposed for several days successively
to 212° Fahrenheit without sustaining any change.

Samples have also been heated for several hours daily,
during several days, to a temperature ranging from 300 to
320 Fahrenheit. The picrate of ammonia was slowly
volatilised from the powder by this treatment, just as the
sulphur would be from gunpowder. In other respects the
powder was unchanged.

A sample of picric powder, which had not been submitted
to pressure, was exposed in an atmosphere saturated with
moisture for 18 days, when it had absorbed 14 per cent of
water; it was then exposed to the open air at the ordinary
temperature (September, 1870), and was found to have
parted with the whole of the water absorbed.

At the end of 20 days another sample was exposed to the
damp atmosphere until it had absorbed 5 per cent of water
in 6 days; upon subsequent exposure day and night to the
air it returned to its original weight in 8 days. Its exposure
to the open air day and night was afterwards continued for
40 days, in the months of September and October, and its
weight ascertained early each morning. The maximum
increase in weight during the experiment was 6 per cent.
On the 4oth day, as on several other days during the experi-
ment, it had returned to its original weight, and its pro-
perties were unchanged.

Not the slightest indication has been obtained, in very
searching experiments, that picric powder is in any respect
more prone to change than gunpowder.

Further trial of picric powder will be combined with the
trial of gun-cotton pulp as a bursting charge for shells.

In the opinion of the Dire¢tor of Artillery, picric powder
has the disadvantages of gunpowder as regards danger, and,
on the other hand, is not equal to gun-cotton as to power or
safety.

The quantities of picric powder already tried have been
small, and it has not as yet developed qualities to lead
to the conclusion that it will either supersede gunpowder or
gun-cotton.

Considering, therefore, that as the qualities of gunpowder
are known, and those of gun-cotton are being developed, he
thinks it would be premature to introduce picric powder
into the service at present, but that it had better remain in
an experimental stage until its actual properties and com-
parative safety are more fully known.

But the Director of Naval Ordnance considers it desirable
that further experiments should be carried out with picric

EEE

1874.1 British Artillery Matériel. 45

powder, as it may prove a valuable explosive for shells and
the Harvey and outrigger torpedoes, where the amount of
charge is limited.

VI. The following experiments have been made by the
Special Committee on Explosives upon an explosive sub-
stance termed “‘ Pyrolithe,” which is being manufactured in
the town of Middlesborough, to determine whether it is of
such a character as to bring it within the meaning of section
Got Act 23 and 24 Vict., c. 139 :—

I. 1 lb. tin gunpowder canister (obtained from Messrs.
Curtis and Harvey) filled with pyrolithe taken from
No. I cask.

The canister was laid upon the ground, and the material
ignited by means of a piece of Bickford fuze placed in
a hole in the side.

The contents burnt with considerable violence, but
without exploding; the solder of the case melted almost
immediately, and the pyrolithe burnt fiercely from the
apertures thus caused until consumed.

2. I lb. tin gunpowder canister filled with pyrolithe taken
from No. 2 cask.

The nose of the canister was placed on the ground to
prevent it from being immediately blown off, and a small
piece of iron was placed on the canister to weight it, and to
represent the condition of one package in a box, or under
others.

The material was ignited (as in the previous case), and
exploded with a dull but decided report, and with sufficient
force to project the canister (which was ripped open) to a
distance of fourteen yards.

3. r lb. tin gunpowder canister filled with pyrolithe from

the cask not marked.

The results were the same as those obtained in No. 1 ex-
periment.

4. I lb. tin gunpowder canister filled with pyrolithe from

the cask not marked.

This canister was placed in a fire of wood and coals laid
in abrazier. In about four minutes the pyrolithe ignited
and burnt fiercely, but without exploding. The solder of
canister was melted.

5. Small wooden keg (with a capacity to contain 5 lbs. of

gunpowder) filled with pyrolithe from No. 1 cask and
headed up.

The keg was ignited by means of a piece of Bickford fuze

46 British Artillery Matertel. (January,

introduced through a hole in the side. On the pyrolithe
taking fire the head of the.keg was blown out with a slight
report, and the material then burnt rapidly away.

6. Small wooden keg filled with pyrolithe from No. 2
cask.

In order to prevent the head of the keg being too readily
blown out, and to represent the condition of barrels stacked
one on the other, a weight of about 50 lbs. of iron was
placed on the head.

The pyrolithe on being ignited blew the head and the
weight off with a decided report, and having thus found a
vent burnt rapidly away.

7. Quarter casks, I, 2, and 3 (containing about 20 lbs. of
pyrolithe in each) headed up, placed in original
packing case, and then covered over with shavings
and wood.

In a few minutes after the shavings and wood were
ignited, one cask caught and burnt violently ; in about 15
seconds more the second cask caught and the flame became
more violent; and in about 30 seconds the third cask
caught, and caused an almost explosive burst of flame; the
whole then burnt with considerable fierceness until con-
sumed.

On full consideration of the results the Committee are of
opinion that under conditions which might arise in con-
nection with the manufacture, transport, or storage of
pyrolithe, its ignition would be followed by a more or less
violent explosion, and consequently the character of this
substance comes within the meaning of the Act quoted.

Samples of pyrolithe from each of the three casks were
forwarded to the Chemist to War Department for analysis,
and the following are the results obtained :—

Soluble matter Composition.

consisting of nitrates, ~ ar Paves
Description of Sample. carbonate of soda, F ee
and Sulphur. Saw- C&D A8©
sulphate of soda. dust. wioisenea
DG. Ayes oe sien’ uate Serta eyo 16°00 =613'06 g'or
S.M.
8C. ; : : ;
No. 2, P.=- Spee ae 73°08 16°12 10°80 8°88

No 3, not marked. . . +. 69°89 .16°36 Z9°7Q ee
Old sample which mae)
been in Major Majendie’s 70°94 16°14 12°92 3°07
possession for some time. |

1874.] British Artillery Matériel. 47

VII. Complaints, it appears, are frequently made with
regard to the irregularities in burning of Boxer wood time-
fuzes, especially in mountain batteries, under varying
atmospheric pressure above the sea-level.

The whole subject of the influence of local altitude on
the burning of time-fuzes has been carefully investigated
both practically and theoretically,—

Practically by Quartermaster Mitchell, in India, in 1849,
at different altitudes, viz.:

St. Thomas’s Mount . . . Sea level.
Bangalore . .. s+ <- » = ooofeet:
omeiteny 9.) 2. 255. 16500.",,

Cctacamund 4) 4i.s “2. + +7300

99

Theoretically by Professor Frankland, in 1860, and subse-
quently, practically, by the French Academy of Science, at
altitudes, viz. :—

Oonishi as as ets eso feet:
eIMCEEO 2 Fs on. oe ss SOO). ,,
@henallettis: = ours ee ORT |

The agreement in these different and distinct observations
was most remarkable, and from them was deduced the fol-
lowing practical rule :—

That the time of burning of a fuze increases in the ratio
of ovoort of its value for each diminution of 0°0394 inch of
barometrical pressure; or, in other words, of about 0°03 of
its value for each variation of 1 inch pressure. Atmospheric
pressure diminishes almost uniformly at the rate of 1 inch
for every 1000 feet of altitude; hence the time of burning of
a time-fuze increases 0'03 of its value for each increase of
1000 feet of altitude, or 0°003 of its value for each variation
of roo feet of altitude.

Thus if a g-seconds fuze burns exactly g seconds at the
sea level, it will burn 11°16 seconds at an altitude of 8000 feet
above the sea. The times of burning of the fuzes at the
sea level will, in future, be placed in the cylinders, together
with a notification that ‘“‘ The time of burning increases
nearly 3 per cent for every 1000 feet of altitude.”

IX. It is most important that an efficient gas-check
should be provided in order to prevent the erosion in the
bores of muzzle-loading rifled guns which is caused by the
scoring rush of gas over the top of the shot, more especially
when firing with pebble-powders. Various tin cups and
cow-hide wads, &c., have been tried, at present without
success, and the service wad is discontinued as useless.

X. Colonel Inglis’s muzzle derrick will be adopted for

48 British Artillery Matériel. [January,

g-inch guns and upwards when mounted in open batteries
and en barbette.

XI. The 400-lb. shell, common to-inch, when fired from
the 18-ton gun, has been found sufficiently strong to pene-
trate the sides of wooden unarmoured ships without breaking
up; but with regard to the 7-inch projectile from the
go-cwt. gun, the Committee come to the following con-
clusions :—

1. That the present experiment affords no trustworthy
evidence of the relative destructive effect which would
probably be produced by common shell after passing through
the side of wooden and iron unarmoured vessels. It is
worthy of note that after passing through the side of the
wooden target, a shell, if it does not break up or explode at
once, is liable to turn sideways. Under such circumstances
the projectile would probably lodge, and might act as a mine
in the opposite side. Exact information on this point
cannot well be obtained without firing at a decked structure,
or an actual vessel.

2. So far as destructive effect is concerned, the Committee
are unable to form any trustworthy estimate of the com- ~
parative value of any of the projectiles fired.

The special 7-inch projectile has the advantage of an in-
creased bursting charge, but this appears to entail a loss of
strength in the shell, and, looking to the inconvenience
of adopting a new pattern, the Committee, on the whole,
prefer the service shell, weighing filled 115 lbs.

3. The distance at which common shell break up or
explode after passing through the side of a vessel, either of
wood or of iron, depends in a great measure on the nature
of the resistance met with. If the shell hits on a knee,
a rib, or a diagonal iron brace, it almost invariably breaks
up or explodes in passing through the side; if, on the other
hand, it passes fair between two ribs in a place where the
resistance is confined to the wood planking or iron plating,
it may not break up or explode until it has passed from 6 to
to feet from the side.

Complete information on these points cannot, however, be
obtained without practice at an actual ship.

4. That the projectiles fired from both guns were liable to
break up (without bursting) in passing through either of the
targets. The shells appeared to break up whether they
were filled with sand or with gunpowder ; in the latter case
the bursting charge in several instances merely fired. The
full effect of the explosion did not appear to be realised
unless the shell struck on a part of the target where, owing

1874.] British Artillery Matériel. 49

to increased resistance, the onward velocity was suddenly
checked.

XII. The Moncrieff system of mounting guns has been
tried successfully with guns up to 7 tons weight, can be
applied with advantage to g-inch guns of 12 tons, and
possibly extended to guns of 18 tons and upwards.

The g-inch carriage subjected to trial was of the improved
type, known as Pattern II. It differs from the original con-
struction adopted in the case of the 20 7-inch muzzle-
loading Moncrieff carriages made for service, and from the
first experimental carriage for g-inch guns of 12 tons, in the
following particulars :—

1. The carriage proper is dispensed with, and the gun
rests directly on the elevators. By this arrangement, the
strain which, in the carriages of original construction, was
received upon the rear axletree at the moment of firing, is
now conveyed through the vertical elevating bars to a
grooved stool bed upon which these bars slide. By this
means the blow which previously was met directly is now
gradually absorbed.

2. The gun comes down into a constant position for
loading, whatever elevation or depression it may have in
the firing position.

3. It is simpler and more compact, although heavier, but
it affords greater facility for loading and elevating.

Notwithstanding the increased cost of the Moncrieff as
compared with the service carriage and platform, his system
(an ordinary barbette unprotected battery always excepted)
is considerably cheaper than any other, constructed of either
earth or stone protected with iron shields. As compared
with the cost of a casemated battery, with shield, as esti-
mated for a g-inch gun of 12-tons, the balance in favour of
the Moncrieff system would amount to about £1800 per gun,
while, as compared with that of an open battery, with
shield, with and without splinter-proof cover, the saving
would be respectively £450 and £667 per gun.

As regards economy and efficiency, therefore, the Com-
mittee consider the Moncrieff system compares very favour-
ably with that of the service, especially when it is considered
that, from its extensive lateral range, one gun mounted on a *
Moncrieff carriage may do equal work with two or more
guns mounted behind shields.

; The system will be found particularly well adapted
or,—

(1.) Mounting guns in salients, &c., of land defences,

and—

VOL. IV. (N.S.) H

50 British Artillery Matériel. (January,

(2.) Mounting guns for subsidiary defence of existing
heavy sea batteries ; they allude more particularly to
such works as Picklecombe, Bovisand, &c., the guns
of which being essentially armour piercers, should
have associated with them guns of lighter calibre for
shell fire.

(3.) The defence of the great commercial harbours.

The expense of mounting a few 12-ton or possibly heavier
guns on Moncrieff carriages would be considerably less than
placing them behind shields or in casemates; while the in-
creased protection afforded to the men over that of guns
en barbette would be a matter of great importance.

With regard to the employment of the Moncrieff system
for mounting guns of large calibre on sea defences, the
Committee consider that it might be resorted to with advan-
tage, but the extent of its application necessarily depends
upon local and other considerations, of which they can have
no cognizance.

Should it, however, be contemplated to project new works
for the defence of important positions, or to supplement
existing works by others of the present type, the Committee
are strongly of opinion that the designs should be re-con-
sidered with a view to the employment of the Moncrieff
carriage.

XIII. The manufacture of 8-inch rifled muzzle-loading
howitzers for the service is being proceeded with.

1. As a howitzer, this piece will be usually employed in
destroying earth works, in breeching unseen defences, or in
shelling buildings, ships, &c.

In these operations the elevation will seldom exceed 20°,
and, as a rule, high charges will be used, the shells being
designed to burst on impact, or by means of a percussion
fuze.

2. As a mortar, it will be used in bombarding magazines
or other bomb-proof buildings; in dropping shells upon the
decks of vessels; in dislodging troops from cover, or in
destroying matériel behind cover, &c.

In these operations the elevation may vary from 20° to 40°,
or even higher angles, and the charges from the highest to
the lowest. Asa rule, however, low charges will seldom be
used, except in dislodging troops from under cover, and
under these circumstances a time fuze will generally be
found most effective.

Elongated projectiles falling at angles of 50° to 70°, or
under conditions of vertical fire, will enter the ground for

—————

1874.] British Artillery Mateértel. Gi

several feet before a percussion fuze will have time to act;
thus the effect of the explosion will be comparatively slight
in a lateral dire¢tion.

The effect of shells burst in the air, over the heads of
troops, or just in clearing the parapet, would be much more
searching than the effect of shells which had entered the
ground before exploding.

Again it is an open question which nature of fuze would
be best when firing at bomb-proof structures.

It is possible that under these circumstances the wood
time fuze would act percussively, but by cutting it long the
shell might be given time to enter to its greatest depth for
exploding ; it would thus act with the greatest advantage as
a mine.”

XIV. From experiments with guns fired from casemates,
and behind shields at Picklecombe, Bovisand, and elsewhere
it has been found—

1. That a slight difference in protrusion of muzzle of gun
has an immense effect with regard to concussion and smoke,
which are much lessened.

2. That the mantlets materially lessen the amount of
smoke and concussion in casemate, but not sufficiently so to
allow of many contiguous guns being worked at close interval
when firing rapidly.

The side pieces or wings are somewhat cumbrous to
move; do not allow sufficient play for bringing the mantle
up to the gun when trained at an angle; and are in the way
of men loading when the gun is trained at any considerable
angle.

3. The solution of chloride of calcium to render the rope
uninflammable answers admirably.

XV. The experiments with the 35-ton guns have been also
satisfactory. Some difficulties have been experienced in
loading when the recoil is less than five feet, and it is
necesssary for one of the gun detachment to hold up the end
of the rammer outside the work, the leverage of the stave
being too great for Nos. 2 and 3 to support it within.

The shooting of the common shell of 618 lbs., with full
charge of 85 lbs. of pebble powder, is better than that of the
Palliser shell of 7oolbs., and battering charge of 110 lbs.,
which is principally due to the shearing of the front studs
of the latter and consequent increase of gyration, which
causes inaccuracy and a want of uniformity in range and
deflection.

Meantime improvements, both in armour-plated ships and
armour-piercing guns, continue to be made, and whilst at

52 Geological Survey of the Umted Kingdom. {January,

Portsmouth the double turreted Inflexible is being built with
20-inch plates for her citadel at Woolwich, a sixty ton
experimental gun, with calibre of 15 inches, to throw a
projectile of 1100 Ibs. weight, is in progress. This new gun
we learn is fitted with a breech-loading apparatus, but no
details have yet been published.

V. THE GEOLOGICAL SURVEY OF THE UNHE®
KINGDOM.

Rs the applications of science to industry are every day

becoming more important, it may be interesting to

review the origin and progress of our National
Geological Survey. This institution was established for
the purpose of arranging, in a form easily accessible to the
public, a complete body of information respecting the
geological structure of the British Islands, and the dis-
position and extent of their mineral wealth.

It was about forty years ago when Sir Henry (then Mr.)
De la Beche proposed to the Government to publish copies
of the ordnance maps geologically coloured. This proposal
being acceded to, the Survey was commenced single-handed
by him, in the year 1834. Having for some time previously
worked at the geology of the west of England, he was the
better prepared to issue geological maps of Cornwall, to
which his attention was first given. Subsequently, a small
branch of the Trigonometrical Survey (then under the
superintendence of Colonel Colby, R.E., F.R.S.), was
formed under the directorship of De la Beche.

About the same time, a geological branch of the Ordnance
Survey was formed in Ireland, and placed under the charge
of Captain Portlock.

In 1835, De la Beche suggested to the Chancellor of the
Exchequer that a collection should be formed, and placed
under the charge of the Office of Works, containing speci-
mens of the various mineral substances used for roads, in
constructing public works or buildings, employed for useful
purposes, or from which useful metals were extracted. In
1837, the sanction of the Treasury was given to this design,
and a building in Craig’s Court was devoted to the work of
the Office and the reception of the specimens. This was
replaced by the more suitable building now occupied at
Jermyn Street, the Museum of Practical Geology, which
was opened to the public in 1851.

1874.] Geological Survey of the United Kingdom. 53

In Ireland, the specimens were first formed into a museum
at the Ordnance Survey Office in Belfast, and afterwards
transferred to Dublin, where they are now placed in the
Museum of Irish Industry.

In 1845, the Geological Survey was transferred from the
Ordnance Survey to the charge of the Chief Commissioner
of Her Majesty’s Woods, Works, and Land Revenues; and
an Act of Parliament was passed, giving the necessary
powers to all duly appointed officers of the Survey to
examine every portion of the country without fear of being
prosecuted as trespassers on private property.

Professor A. C. Ramsay was appointed the first Local
Director for Great Britain, and Captain (now Sir Henry)
James for Ireland, acting under De la Beche as Dire¢ctor-
General. Meanwhile the Office of Woods and Forests was
modified, and, on the formation of the Department of
Science and Art in the year 1854, the Geological Survey of
the United Kingdom was consigned to it, at first under the
Board of Trade, and afterwards under the Committee of
Privy Council for Education.

Since this period, great changes have taken place in the
direction and organisation of the Survey, while the staff has
been largely increased. The Director-General, Sir Henry
De la Beche, died in 1855, and was succeeded by Sir
Roderick Murchison, who died in 1871. Professor Ramsay
then received the appointment, and Mr. Bristow was made
Director for England and Wales. Captain James (now
Director of the Ordnance Survey) was succeeded in Ireland
by Dr. Oldham (now Superintendent of the Geological
Survey of India), Dr. Oldham by Mr. Jukes, who died in
1869, and he by Mr. Hull. Scotland, too, has been severed
from England, and Mr. Geikie appointed Director.

As at present constituted, therefore, the Geological Survey
of the United Kingdom is under the Diretor-Generalship
fimeroiessor, A. C.. Ramsay, LL.D..F.R.S. Mr. -H. W:
Bristow, F.R.S., &c., is Director for England and Wales;
Mr. Edward Hull, M.A., F.R.S., is Director for Ireland;
and Professor Archibald Geikie, LL.D., F.R.S., for Scotland.
The field-staff embraces two distri¢t-surveyors, eight geolo-
gists, twenty-four assistant-geologists, and one fossil col-
lector, in England; one distri¢t-surveyor, three geologists,
nine assistant-geologists, and two fossil-collectors, in Ireland;
and one district-surveyor, two geologists, six assistant-geolo-
gists, and two fossil collectors in Scotland. In addition to
these officers, Mr. R. Etheridge, F.R.S. (Palzontologist),
ead rotessor I. H.- Huxley; LL.D., F.R.S- (Naturalist),

54 Geological Survey of the United Kingdom. [January,

with two assistants, have the naming and arranging in the
museum at Jermyn Street of the fossils collected on the
Geological Survey of Eagland and Wales.

The results of the Survey operations will be learnt from
the published maps, memoirs, and sections. ‘The following
statistics show the present state of the progress of the
Geological Survey.

The whole of Wales has been completed on the one-inch
scale, while in England twenty-five counties have been
finished. The area which remains to be surveyed comprises
portions of Northumberland, Cumberland, Westmoreland,
Durham, Yorkshire, Lancashire, the Isle of Man, Lincoln-
shire, Nottinghamshire, Leicestershire, Cambridgeshire,
Huntingdonshire, Norfolk, Suffolk, and Essex. In England
and Wales, which comprise 110 sheets, 80 complete sheets
have been published on the one-inch scale ; while numerous
maps on the scale of six inches to one mile have been pub-
lished to illustrate the coal-fields of Yorkshire, Northumber-
land, Durham, and Lancashire. A number of sheets adja-
cent to the Yorkshire coal-field, and not intended for
publication, are deposited for reference at the Geological
Survey Office, where they can be seen, and (under certain
conditions) copies may be obtained. Portions of the
western counties, Gloucestershire and Somersetshire, have
been re-surveyed in greater detail.

In Ireland, which comprises 205 sheets on the one-inch
scale, 135 sheets have been published, and what remain to
be finished comprise portions of Galway, Mayo, Roscommon,
Sligo, Leitrim, Fermanagh, Cavan, Monaghan, Tyrone,
Donegal, Londonderry, Antrim, Down, Armagh, and Louth.
All these maps were surveyed on the scale of 6 inches toa
mile, and reduced for publication. Altogether seventeen
counties have been completed.

In Scotland, which comprises 120 sheets on the one-inch
scale, 18 maps have been published, illustrating the geology
of portions of Wigtonshire, Ayrshire, Kirkcudbright,
Dumfriesshire, Lanarkshire, Renfrewshire, Peeblesshire,
Dumbartonshire, Stirlingshire, Linlithgowshire, Edinburgh-
shire, Haddingtonshire, Berwickshire, Fife, and Kinross,
Maps on the 6-inch scale have been published to illustrate
the coal-fields of these counties.

Numerous horizontal sections drawn to the scale of 6
inches to the mile, and vertical sections, on a scale generally
of 40 feet to an inch, have been published to illustrate the
geological structure.

Memoirs and Explanations, containing accounts of the

.
£
=
,
3

ee Te

1874.] Geological Survey of the United Kingdom. 55

stratigraphical relations of the rocks, their characteristic
fossils, and notes on the mines and minerals accompany
most of the maps. Special memoirs on large areas, and
detailed descriptions of fossils have also been published.

From three to four thousand square miles are annually
surveyed in the United Kingdom. There is, however,
much old ground to be gone over in mapping the superficial
deposits, which not only have an important economic value
in many instances, but are also intimately connected with
questions of health, of drainage, and water-supply.

The Museum at Jermyn Street well illustrates the appli-
cations of geology, by exhibiting a series of rocks and
minerals, and their adaptation to purposes of use and
ornament. An extensive paleontological collection likewise
illustrates the geological maps ; the study of fossils proving
an important guide in the identification of strata.

It is by studying the Maps, Se¢tions, and Memoirs
together, that the great practical value of the Survey is
understood. The Maps themselves will show the superficial
extent of the different strata, whether gravel, sand, clay,
limestone, slate, sandstone, marl, or alternations of these
rocks, such as clay and limestone, sand and gravel. The
colours representing these geological formations are an
indication of position and age. To learn their thicknesses,
mineral characters, &c., the Memoirs must be consulted;
while to understand their underground extension, the
Sections will prove necessary.

Hence the applications to Agriculture, Engineering, and
ArchiteCture, and still more to Mining, will be at once
apparent.

It is needless to remark upon the fruitless trials for coal
which have been made even in recent years. The late
Professor Jukes has stated that the money wasted in such
searches, of which he had been personally cognisant, could
not have been less than £150,000. The Geological Survey
has checked much of this fruitless expenditure.

Some of the more important results of the Survey are
shown in the Report of the Royal Coal Commission. The
area of the exposed coal-measures of England is estimated
at about 2840 square miles. The investigations of Professor
Ramsay have led him to conclude that 3141 square miles of
coal measures are present beneath the Permian and Triassic
strata—301 square miles more than the area of our exposed
coal-fields !

1874.] (56)

VI. GALL’S DISCOVERY OF THE PHYSIOLOG®
OF THE BRAIN, AND ITS RECEPTION:

By T. SyMEs PRIDEAUX.

“ Strictly speaking you only play the part of puppets in a show; when certain cerebral organs
are put in action, you are led according to their seat to take certain positions, as though
you were drawn by a wire, so that we can discover the seat of the acting organs by the
motions. I know that you are blind enough to laugh at this; but if you will take the
trouble to observe, you will be convinced that by my discovery I have revealed to you
more things than you were aware of.’—‘‘ GALL, in a familiar Letter to his Friend

Baron RETZER, 1798.”

ae
EF we are to accept the verdict passed amidst mutual
a congratulations by the Physiologists of the period

assembled at Bradford, we are on the eve of obtaining
a revelation of the physiology of the brain by the localised
application of electricity to its surface. Facts carefully
observed and accurately recorded must always possess an
intrinsic value, but it is possible to err in their interpretation;
that this has been done to some extent with reference to
the experiments in question, and exaggerated expectations
founded on misconception indulged in as to the amount
and accuracy of the knowledge to be expe¢ted from this
source, is to me abundantly clear.

Enthusiasm in the pursuit of knowledge is doubtless
amongst the highest of the characteristics which distinguish
the noblest specimens of humanity from the common herd of
mankind. As an evidence of mental activity, the jubilation
with which the announcement of the results of applying
electricity to the surface of the brain has been received is
in the highest degree satisfactory. The more cordial the
reception accorded these experiments, however, the more
prominently the question obtrudes itself,—What are the
distinctive differences in the path pursued to attain one
common object by Fritsch, Hitzig, and Ferrier, and the
method of Gall, that should occasion the results of the
former to be welcomed with acclamation, whilst those of
the latter were received with the hail of sneers, scoffs,
ridicule, misrepresentation, and contumely ? Tothe student
of the human mind the difference, or rather contrast, offers
a curious and interesting problem.

Can we find a partial explanation of the anomaly in the
more purely physical character of the recent method of
research—that the subject of attention in the one case isa
movement visible to the senses, in the other a mental
quality, an abstraction which presents no sensuous object to
the mind? What is certain is, that many men have great

i
;

sieieiiaeeat elite eal

1874.] Physiology of the Brain. 57

taste and capacity for the observation, description, and
arrangement of material facts, who are singularly deficient
in the power of contemplating abstract existences. The
majority of men appear to require a physical substratum
for their thoughts. Their ideas are almost limited to images,
or pictures of outward objects presented by the external
senses; or secondly, to conceptions of actions being a change
in the relation of material objects; or thirdly, to bodily
sensations arising from the action of the external senses.
Hither the specialised senses—taste, smell, hearing, and sight
—or the diffused sense of feeling, co-extensive with the
surface of the body, and hence adopted as a generic term,
and applied metaphorically (with its opposite poles, pleasure
and pain) to all internal affections. They have not adequate
power of abstraction to separate the subjective from the
objective. Not analytical power sufficient to dig phantoms
from their consciousness, isolate them from their surround-
ings, and hold them continuously before their mental vision
for contemplation. They catch a glimpse of a figure fora
moment, but before they have time to study its features it
dissolves away like a wreath of mist. Now the subject
matter of Phrenology is mental qualities, not material
objects ;. whilst, in addition to its abstract basis, it superadds
the doctrine of the dependence of the mental functions on
certain external relationships of form and size, successfully
to appreciate which demands an amount of preliminary
study hardly likely to be expended on the problem, by those
to whom one of the factors in the equation presents the
aspect not merely of an unknown, but of an incom-
measurable quantity. Non omnia possumus omnes, indeed,
it is usually those whom some predominating instinct
prevents being too discursive and keeps in one path of
study by whom additions to the sum of human knowledge
are made. Let us be thankful to the student, whose range
of thought is limited to objects of sense, for his con-
tributions to his own department ; but do not let us regard
him as an authority in others, nor commit the shallow
blunder of citing his indifference to, or disbelief in, the
invisible rays at the higher extremity of the spectrum as an
argument for their non-existence. We have cultivators of
the physical sciences, mathematicians, astronomers, natural
philosophers, chemists in abundance, plenty of naturalists,
ready to seize and describe all the peculiarities in form,
size, weight, colour, distribution, and habits, of everything
that has life. We have even a limited supply of meta-
physicians and psychologists, who deal with abstractions and
VOL. IV. (N.S.) I

58 Physiology of the Brain. (January,

words in contradistinction to things, and inhabit an ideal
world of theirown. The dealers in things and the dealers
in abstractions mostly dwell apart, and too often regard each
others’ pursuits with ill-disguised contempt.

Now the phrenologist requires to unite to a considerable
extent the capacities and tastes of both classes; to combine
the powers of mental analysis—the facility for detaining
abstractions before the mind’s eye for study—of the meta-
physician and psychologist, with the instinct of observation
and quick perception of physical differences by which the
naturalist is distinguished—and in the fact that individuals
who combine the two phases of capacity will be less
numerous than those who possess one of the qualifications
singly, we see an explanation of the cause why the scientific
cultivators of phrenology are fewer in number than either
the physicists or the metaphysicians.

In scanning the causes of the hostility Phrenology has so
widely encountered, amongst others we must not omit to
notice its close bearing on the personality of individuals.
Men with little heads, little minds, but great vanity, rebel
against a standard of capacity which gauges them corre¢tly.
A science which renders it possible—

5 : : : “A des signes certaines
Reconnaitre le coeur des perfides humaines,”
will always have antagonists to whom such an idea is
distasteful. The whole of the genus humbug, the empirics
and impostors of the day, and men conscious of being at
bottom thoroughly dishonest and unprincipled, instin¢tively
recoil from a system which threatens to unmask their
moral deformities to the eyes of the world, and reveal their
true features, despite a whole wardrobe of trappings of
duplicity. Napoleon boasted of having greatly contributed to —
put down Gall. His own medical attendent, Corvisart, one
of the greatest physicians France ever produced, was an
admirer of Gall, and vainly endeavoured to introduce him
to the Emperor. ‘‘Corvisart,” says Napoleon, ‘‘ was a
great partisan of Gall, and left no stone unturned (fit
limpossible) to push him on to me, but there was no
sympathy between us.” In short, Napoleon confessed he
felt the greatest aversion for those ‘“‘who taught that
Nature revealed herself by external forms.”

Again, the bulk of mankind have no doubt been organised
by nature to lead a life of action, to do, and not to think. In
youth they are plastic, and readily receive the impression
stamped by their teachers, but by mature age the receptivity
of childhood has vanished, and the clay of which they are

1874.] Physiology of the Brain. 59

composed refuses all attempts to mould it afresh; and
especially is this the case where the egotistic feelings of self-
love and vanity outweigh the pure love of knowledge for its
own sake. Such men may indeed imbibe newideas, and acquire
an increase of knowledge as they grow older, but the new
knowledge must have some points of affinity and harmony
with the old, to be cordially welcomed. Above all, it must
not threaten the subversion of those existing canons of
belief which have hitherto guided them on life’s journey, or
it will infallibly excite antipathy and antagonism. Every
day we Have the spectacle of the direct testimony of facts
being ignored and rejected without examination, from the
inference that they are opposed to some cherished belief.
Even the scientific par excellence, the professed philosophers,
are not exempt from this human frailty; touch but the ark
that enshrines the object of their worship, and you shall see
the bigotry and intolerance with which they credit the
theologian rivalled, if not outdone. As at the advent of
Phrenology it encountered the antagonism of the religious
world from its supposed tendency to materialism; so, at the
present hour, many of our leading physicists shut their eyes
to the curious phenomena of (the so-called) spiritualism,
and open their mouths to assail its investigators, because
they fear that these phenomena clash with that materialistic
philosophy which constitutes the staple article of their
scientific creed.

How vast a portion of our present stock of scientific
knowledge would be non-existent if no one had been found
to ‘‘take an interest” in the phenomena of magnetism! and
can the most bigoted apostle of the new positive-physical
gospel venture to assert that a domain of fact as wide in
its extent and fruitful in its result may not lie hidden,
awaiting conquest by man in this force of source unknown,
the conditions attending the presence of which, though
yet undiscovered, we may be assured are governed by laws
as definite and immutable as those of gravitation. We do
not yet know how to multiply mediums at pleasure, as we
do magnets, because we know neither the species of
loadstone nor the kind of manipulation required, but all
honour to those who are engaged in the research.

Apparently as long as psychologists were content to frame
theories out of their own consciousness, and confined
themselves to abstractions, their researches created no
antagonism in the physicists who occupied themselves with
the study of material objects and their properties and
functions ; but when these saw their own peculiar province
invaded, and the physiology of the highest organ of the

60 Physiology of the Brain. (January,

body, to them an enigma, for the solution of which neither
their ‘tastes nor capacities were adapted, declared to be
unravelled by a method of study for which they had no
proclivity, and by an individual who had altogether surpassed
them in their own province of anatomy, their pride rebelled,
and their wounded amour propre found vent in denunciations
as outrageous and absurd as ever greeted the author of a
new discovery. English metaphysicians, and immaterialist
divines also, led by English anatomical authorities to regard
the propounder of these new doctrines as an ignorant quack,
were not slow in joining the chorus of detra¢tion and abuse
against the audacious innovator, who overthrew all their
cherished theories as to the independence of the mind on
organisation—the former viewing the doctrines of Gall
with profound contempt and disgust as tending to degrade
man to the level of brutes, the latter with repugnance and
alarm as threatening to sap the foundations of religion.

. Dr. John Gordon, a lecturer on anatomy of great reputation
in Edinburgh, in an article in the ‘‘ Edinburgh Review,” in
1815, said, ‘‘ We look upon the whole doétrines taught by
these two modern peripatetics (Drs. Gall and Spurzheim),
anatomical, physiological, and physiognomical, as a piece of
thorough quackery from beginning toend.” Lord Jeffrey, inthe
same periodical, in 1826, designated the doctrines as “‘crude,”
“« shallow,” ‘‘puerile,” ‘‘fantastic,’” ‘ dull,” “dogmatiens
‘incredibly absurd,” “foolish,” ‘‘ extravagant,” and ‘‘ trash.”
The ‘‘ Quarterly Review,” in their notice of Madame de
Stael’s ‘‘L’Allemagne,” censured her for being “ by far
too indulgent to such ignorant and interested quacks as the
craniologist Dr. Gall,’ and in No. XXV. the same Review
declared the new science to be ‘‘ sheer nonsense,” and
designated Dr. Spurzheim as ‘“‘a fool.” The Rev. Thomas
Rennell, Christian advocate at Cambridge, in his “‘ Remarks
on Scepticism, especially as it is connected with the subjects
Organisation and Life,’’ assures his readers that the system
of Gall and Spurzheim ‘‘is annihilated by the commonest
reference to fact,” spoke of “‘ its absurdities,” of this ‘‘ master-
piece of empiricism,” and designated it as ‘“‘the flimsy
theories of these German illuminati.’”’ Whilst as late as 1836,
Sir CharlesBell wrote—‘‘ The most extravagant departure
from all the legitimate modes of reasoning, although
still under the colour of anatomical investigation, is the
system of Dr. Gall. Without comprehending the grand
divisions of the nervous system, without a notion of the
distinct properties of the individual nerves, or having made
any distinction of the columns of the spinal marrow,

1874.] Physiology of the Brain. 61

without having even ascertained the difference of cerebrum
and cerebellum, Gall proceeded to describe the brain as
composed of many particular and independent organs, and
to assign to each the residence of some special faculty.”

The insular ignorance of Gall’s anatomical discoveries,
position in the scientific world, and true character displayed
in these insulting criticisms, is no less disgraceful than
astounding. Professor Hufeland, an anatomist and phy-
siologist of European reputation, thus expresses himself
concerning Gall:—‘‘It is with great pleasure and much
interest that I have heard this estimable man himself
expound his new doctrine. I am fully convinced that he
ought to be regarded as one of the most remarkable
phenomena of the 18th century, and that his doétrine
should be considered as forming one of the boldest and
most important steps in the study of the kingdom of nature.
One must see and hear him to learn to appreciate a man
completely exempt from prejudices, from charlatanism, from
deception, and from metaphysical reveries. Gifted with a
rare spirit of observation, with great penetration and a
sound judgment, identified, as it were, with nature, he has
collected a multitude of signs of phenomena which nobody
had remarked till now—has discovered the relations which
establish analogy between them—has learnt their significa-
tion—has drawn consequences and established truths,
which are so much the more valuable that, being based on
experience, they emanate from nature herself.”

**The worthy Reil,’’ says Professor Bischoff, ‘‘who as a
profound anatomist and judicious physiologist stands in no
need of my commendation, has declared, in rising above all
the littleness of egotism, that he had found more in the
disseCtions of the brain performed by Gall than he had con-
ceived it possible for a man to discover in his whole
life-time !”

“Loder,” continues Professor Bischoff, ‘‘ who certainly
does not yield the palm to any living anatomist, has ex-
pressed the following opinion of the discoveries of Gall :—
‘ The discoveries of Gall in the anatomy of the brain are of
the highest importance, and many of them possess such a
degree of evidence that I cannot conceive how any one with
good eyes can mistake them. I refer to the great ganglion
of the brain—to the passage of the corpora pyramidalia
into the cruva of the brain and the hemispheres—to the
fasciculi of the spinal marrow—to the crossing of the fibres
under the pyramidal and olivary eminences—to the recurrent
fibres of the cerebellum—to the commissures of the nerves—

62 Physiology of the Brain. (January,

to the origin of the motor nerves of the eyes, of the
trijeminal nerves, of those of the sixth pair, &c. These
discoveries alone would be sufficient to render the name of
Gall immortal; they are the most important which have
been made in anatomy since the discovery of the system of
the absorbent vessels. The unfolding of the brain is an ex-
cellent thing. What have we not to expect from it as well
as from the ulterior discoveries to which it opens the way?
I am ashamed and angry with myself for having, like the
rest, during thirty years, sliced down hundreds of brains as
we cut a cheese, and for having missed seeing the forest on
account of the great number of trees it contained. But it serves
no purpose to distress one’s self, and to be ashamed. The
better way is to lend an ear to truth, and to learn what we
do not know.’”

Which latter piece of advice I commend to the notice of
those little great men, the eminent compilers, who,—devoid
of the original genius which, by perceiving relationships
before unknown and unsuspected, confers new principles on
science,—would fain set themselves up as physiological
authorities on the strength of their book-making capacities.

Not only were the great and important additions made by
Gall and Spurzheim to the anatomy of the nervous system
fully admitted by Cuvier, but their position as the highest
authorities on the subject was so fully recognised in Paris,
in 1813, that the article, ‘‘ Anatomie du Cerveau,” for the
‘‘ Dictionnaire des Sciences Medicales,” was confided to
their care.* All English anatomists, however, have not
followed the suit of Dr. John Gordon and Sir Charles Bell,
in recording at once their jealousy and their ignorance by
absurd denunciation of Gall. Mr. Grainger, the greatest
English authority of his day on the anatomy of the brain
and spinal cord, writes, ‘“‘The true anatomy of the cerebrum
was perfectly unknown till the researches of Gall, and it is
due to the character of this eminent man and of his pupil,
Spurzheim, to state that all our knowledge of the anatomy
of both the brain and spinal cord has resulted from their
inspections ;” and Joshua Brookes, in his lectures, and Mr.
Solly, in his well-known work on the anatomy of the brain,
have done full justice to the anatomical discoveries of Gall.

* The necessary result of the old method of dissecting the brain is thus
pithily described in this article:—‘‘On a mis en usage une méthode de dis-
section trés-défe@tueuse; on ne fesait que des coupes horizontales, verticales,
ou oblique, par en haut ou par en bas et on enlevait successivement des
tranches de cet organe. De cet maniére, on commencait pay détruire les con-
nexions des différens appareils et on procédait sans égard pour lordre dans
lequel les parties se suivent naturallement.”

1874.] Physiology of the Brain. 63

The method pursued by Gall, in seeking to ascertain the
functions of the brain, was by comparing the power of
manifesting particular mental faculties with the size and
condition of particular portions of this organ. Phrenologists
believe this method to be vastly superior to all others, and,
in justification of this opinion, point to the rich harvest it
has produced in contrast to the barren results which have
hitherto been obtained by the employment of mutilations
and the application of stimuli. Is there, at the present
moment, a single physiologist in a position to declare that,
after qualifying himself to judge of the development of the
organs by the requisite study, the result of careful examina-
tion has convinced him that the localities assigned by Gall
to the primitive mental faculties are erroneous? Why is
this sound and legitimate mode of studying the functions of
the brain neglected and ignored by physiologists in general,
‘who seem desirous of exhausting every possible variety of
error before they will adopt it?”” Men of science are usually
eager to avail themselves of every practicable means in
the pursuit of knowledge, but it would appear to be a
desideratum to discover the functions of the brain by other
than phrenological methods.

In addition to employing mutilations, Rolando trephined
the cranium of various quadrupeds, and applied one of the
poles of a voltaic pile to different portions of the brain,
whilst the other was applied to different parts of the body.
With reference to these experiments of Rolando, and the
experiments by mutilation of Flourens, Gall remarked :—

“It is a subject of constant observation that, in order to
discover the functions of the different parts of the body,
anatomists and physiologists have always been rather
disposed to employ manual means than to accumulate a
great number of physiological and pathological faéts,—to
combine these facts, to reiterate them, or to await their
repetition in case of need,—and to draw slowly and succes-
Sively the proper consequence from them, and not to
announce their discoveries but with a wise reserve. This
method, at present the favourite one with our investigating
physiologists, is imposing from its materiality ; and it gains
the approbation of most men by its promptitude and its
apparent results. But it has also been constantly observed
that what has appeared to have been incontestably proved
by the mutilator A., either did not succeed with the mutilator
B., or that he had partly found in the same experiments all
the proofs necessary to refute the conclusions of his prede-
cessor. It is but too notorious that similar violent experi-

64 Physiology of the Brain. |January,

ments have become the scandal of the Academicians, who,
seduced by the attraction of ingenious operations, have
applauded with as much enthusiasm as fickleness the pre-
tended glorious discoveries of their candidates.

‘In order that experiments of this kind should be able to
throw light on the functions of each of the cerebral parts, it
would require a concurrence of many conditions impossible
to be fulfilled. It would first require that we should be
enabled to restrain all the effects of the lesion to that
portion only on which the experiment is performed ; for if
excitement, haemorrhage, inflammation, &c., affect other
parts, what can we conclude? and how can we _ prevent
these inconveniences in mutilations either artificial or
accidental? It would be necessary that we should be able
to make an animal whose brain has been wounded and
mutilated—who is filled with fear and suffering, disposed to
manifest the instin¢ts, propensities, and faculties, the organs
of which could not have been injured or destroyed. But
captivity alone is sufficient to stifle the instincts of most
animals.” ;

Have the results attained by the recent experiments of
Fritsch, Hitzig, and Ferrier a tendency to invalidate these
opinions of Gall, or do they not rather confirm their correct-
ness? I presume it will hardly be pretended that the
function of a single portion of the brain has yet been
discovered by these means,* and I venture to think there is
but little probability of their effeCting such a discovery in
the future, notwithstanding the exaggerated expectations
held out. At present it is palpable that physiologists are
quite adrift as to the real signification of the phenomena
elicited, the true interpretation of which must be sought in
the discoveries of Gall, who maintained the competency of
the surface of the brain to originate muscular movements in
opposition to the current doctrines of physiology and the
asserted proof to the contrary afforded by the experiments
of Flourens, and other mutilators, and whose familiarity
with the faét is recorded in the extract from his letter
to Baron Retzer, in 1798, prefixed to this article.

The explanation of the phenomena obtained by the appli-
cation of stimuli to the surface of the brain, is found in the
fact that those innate faculties which require the aid of the

* A fa& conclusive on this point, and which places in a striking light the
vagueness and want of precision of the results obtained, is the circumstance
that that eminent compiler, Dr. Carpenter, sees in these experiments ‘‘ a remark-
able confirmation” of his transcendently absurd and ridiculous notion,that the
intellectual organs are seated in the back of the head.

1874.] Physiology of the Brain. 65

muscular system to carry out their behests have the power
of originating the movements necessary for this purpose ;
and hence, when Dr. Ferrier applied a galvanic current to
the cortical surfaces of the organs of the instinét ‘‘ to take
Pe = to seize’ prey,” “to destroy)’ (“te fight,” “to
construct,”—movements ‘‘of mastication,” ‘‘of striking with
the claws, or seizing with the mouth,” “of biting and
worrying,” ‘‘of scraping, or digging,” ensued: whilst the
stimulation of the same locality (constru¢tiveness) which
put the fore paws and hind legs in a¢tion in the rabbit,
would, in the beaver, superadd the motion of the incisor
teeth and the tail. What can be more palpable than that
the inferences to be obtained from such experiments are not
only far more vague and indefinite than those furnished by
the employment of the phrenological method, but absolutely
incapable of ascertaining the shape, and defining the boun-
daries, of the organs, as has been accomplished by Gall in
the case of locality, the shape of which he ascertained to be
similar in dogs to its form in man. In short, little more
can be said on behalf of these experiments at present than
that in a cloudy and obscure fourm they lend a vague
general confirmation (not required) to the correctness of
the localities assigned to the primitive faculties by phre-
nologists.

Amongst the many eminent men whose researches and
discoveries have shed honour on the profession of medicine,
Gall will assuredly by posterity be accorded a place second
to none. Man had looked on man, and scanned the face of
his brother in sunshine and in storm, in friendship and in
anger, for countless thousands of years, without having suc-
ceeded in seizing and individualising a single primitive
faculty, much less in discovering its seat. The advent of
Gall broke up the long night of darkness and error as to
their own being, under which the human race had slumbered
for ages. Sensation, perception, memory, judgment, imagi-
nation—the idolze of the past—the stock properties of every
psychological system from that of Aristotle downwards,
instead of being primitive faculties, were clearly demon-
strated by the most masterly analysis and the most un-
answerable arguments to be simply different degrees or con-
secutive modes of action proper to each of the elementary
intellectual faculties, and necessarily variable in strength in
relation to subjects specifically distinét. Gall studied the
maximum or minimum exhibition of certain passions or
capacities compared with the extreme or defective develop-
ment of certain parts of the brain; and when avast number

VOL. IV. (N.S.) K

66 Physiology of the Brain. (January,

of concurrent experiences had satisfied him of a connection,
named the primitive faculty by the simplest words indicative
of its funétion to be found in the vocabulary of every-day
life. Hethus replaced the phantoms of the metaphysicians,
which explained nothing, by terms which speedily asserted
their vitality by being constantly heard in the mouths of the
people to assist them in defining and describing their fellow-
men, thus at once obtaining that sanction from the spon-
taneous dictates of popular common-sense, which is the
surest test of the truth of all fundamental ideas.

It is a common do¢étrine that discoveries are seldom made
by an individual greatly in advance of the scientific mind of
the day, or without other investigators having been placed
by the existing state of knowledge on the same track as the
more fortunate discoverer, who is thus merely credited with
having by a short date anticipated other investigators in
bestowing a new fact, or idea, on mankind. With regard to
the discovery of phrenology, however, made at the close of
the last century by Dr. Gall, if we may judge by the fact
that what he discovered the great mass of his contemporaries
never succeeded in recognising, even when the locality for
research was pointed out to them, and the means of obser-
vation lay in profusion everywhere around, there appears
every reason to believe, that but for the appearance of
a man of his rare and exceptional genius, the vast contribu-
tion to human knowledge for which the world is indebted to
his labours would still have been slumbering in the womb of
futurity. I venture to assert that no body of doctrines were
ever established on a series of observations more cautiously
condu€ted, rigorously scrutinised, and patiently verified
than those of phrenology by Dr. Gall, who devoted his
entire life and all his pecuniary resources to this object,
finding his reward in the consciousness of the importance of
his discoveries, and that prophetic vision of the future
which placed him above contemporary jealousies, and
caused him to exclaim in calm self-reliance, ‘‘ This is truth,
though opposed to the philosophy of ages !”

“‘T have always,” says Gall, ‘‘ had a consciousness of the
dignity of my researches, and of the extended influence
which my do¢trine will hereafter exercise on all the branches
of human knowledge, and for this reason I remain indifferent
to all that may be said either for or against my works.
They differed too much from the received ideas of the
times to be appreciated and approved at first..... My
views of the qualities and faculties of man are not the fruit
of subtle reasonings. They bear not the impress of the age

1874.] Economy of Fuel. 67

in which they originate, and will not wear out with it.
They are the result of numberless observations, and will be
immutable and eternal like the facts that have been
observed and the fundamental powers which these facts
force us to admit.”

Vil. ECONOMY -OF FUEL:
By FREDERICK CHARLES DANVERS, Assoc. Inst. C.E.

has, within the last few years, attracted the attention

of several of our learned societies, and it is one which
cannot fail to grow in importance rather than diminish.
Practically speaking, coal is the only fuel upon which we
can with any certainty rely for our great manufacturing
industries; and although this may, in some measure, be
supplemented by a more extensive use of peat than has
hitherto been the case, still coal must continue to be looked
upon as the great staple upon which the chief of our manu-
factures must continue to depend. Coal, as we have shown
upon several former occasions, exists only to a limited ex-
tent, and our existing resources of that fuel are not capable
of being reproduced, as is the case with wood, and to some
extent also with peat; and, in order to make our coal
supply keep pace with the ever increasing demand upon it,
one of the most important considerations now is, how so to
economise its use in all branches of manufacture and for
steam and domestic purposes as to minimise the amount of
waste which at the present time takes place in the use of it.
With the view, therefore, of pointing out what may be done
in that direction, we purpose now to consider how far
scientific and mechanical improvements have already suc-
ceeded in that direction, and to what extent further economies
may be possible.

Each pound of coal possesses a certain number of heat
units, and to produce any given results from its combustion
requires the development of a given number of heat units;
when, therefore, we find that in order to produce such results
a considerable number of heat units are expended in excess
of the theoretical requirements, it is very evident that a
certain amount of avoidable waste is taking place. It is
not to be expected that the full economic value of coal can
ever be attained in most cases, for were such the case it
_would necessarily follow that the escaping volumes from

ae important question of fuel economy is one which

68 Economy of Fuel. (January,

combustion must only be permitted to escape when all the
heat given out in combustion has been effectually abstracted,
and all radiated heat would also require to be reserved for
useful purposes.

There can be no doubt that coal burnt under a certain
amount of compression will yield the best results; but the
important question is how to regulate the admission of air
so that no more is employed in supporting combustion than
is actually required for that purpose ; any excess above that
amount must tend only to lower the temperature, and so
abstract a certain amount of useful effect from the fuel. The
air admitted for this purpose must also be so regulated as to
ensure its complete combination with the fuel, so that no
air in a free state shall pass away undecomposed. The
channel for escaping vapours should also be so regulated in
size as to give no more than sufficient space for their free
passage in a certain state of expansion, whilst the current
of air into the furnace must also be maintained at a rate
sufficient for the combustion of the proper amount of fuel
for the work to be effected. Now, in order to maintain this
state of things, it is necessary to produce an upward current
in the chimney, and in order to do this, the ascending vapours
must either be forced out by mechanical means, or they must
be allowed to escape at a temperature above that of the
atmosphere. In either case, therefore, it is clear that a
certain amount of heat must be developed in excess of what
would otherwise be required for the purpose. To obtain,
therefore, the full theoretic value of the coal burnt for any
specific purpose must be, under these considerations, abso-
lutely impracticable; the nearer we attain to that point,
however, the less cause of complaint there will be of a waste
of coal taking place in any particular case. As we shall
presently see, the use of hot-blast in iron smelting was
followed by a decided saving in the amount of fuel required
to produce 1 ton of pig-iron, notwithstanding that a certain
portion of it was consumed in first heating the air for the
blast. It will readily be understood how the introduction
of cold air into any furnace must have the immediate effect
of lowering the temperature, and it is found that the amount
of fuel necessary to heat the air before admitting it into
the furnace is less than the amount required to maintain the
temperature within the furnace when it is fed with cold air.
A free current for escape of the vapours of combustion is
followed by the escape of the more volatile portions of the
fuel used, which are therefore absolutely lost ; whilst, witha
strong blast, where there is a free escape—asin a locomotive—
small particles of fuel, wholly uncarbonised, are also carried

1874.] Economy of Fuel. 69

away without doing any effective work. Although, in both
these cases, the greater portion of the fuel remains behind
until it is wholly consumed, only a small proportion of its
effective value is retained, whilst the greater part is lost,
representing so much waste of fuel, a great portion of which
must be looked upon as avoidable loss.

To turn now from generalities to the practical working of
the question, we shall proceed to consider first the appli-
cation of these principles in the manufacture of iron, which
branch of industry alone consumes about one-third of the
total amount of coal raised in the United Kingdom, and
which, therefore, most largely affects the great coal question
of the present day.

Taking the results of iron manufacture in Scotland, we
find, upon the authority of Dr. Percy, that the ton of pig-
iron, as made in 1829 at the Clyde Iron Works, required the
coke of 8 tons 17 cwts. of coal ; whilst in the following year,
owing to Neilson’s invention of the hot-blast to iron furnaces,
the introduétion of air heated to 300° F. brought down the
consumption per ton of pig to 5 tons 34+ cwts. 8 cwts. of
coal were consumed in heating the blast, so that the actual
saving per ton of pig-iron was 23 tons. In 1833, when raw
coal had come to be used instead of coke, 1 ton of pig-iron
was made with 2 tons 53 cwts. of coal, which, with 8 cwts.
for heating the blast, made a total of 2 tons 134 cwts. Hence
by the application of the hot-blast, the same amount of
fuel reduced three times as much iron, and the same amount
of blast did twice as much work as previously.

Subsequently to the attainment of the foregoing results
an increase in the size of the blast-furnace has been followed
by still further economy in fuel used in the manufacture of
iron. The discovery of this fact is due to the iron smelters
of Cleveland. When the first blast-furnace was ere¢ted in
that district by Mr. John Vaughan, in 1851, the practice of
older districts was followed, and the furnace was made
42 feet high by 15 feet diameter at the bosh. Up to 1858
there was a gradual increase of size, the furnaces that year
being 56 feet in height by 16 feet bosh. ‘The results of this
increase of size were so satisfactory that Mr. Vaughan was
led to rebuild one of the old furnaces, increasing its size to
61 feet high by 16 feet 4 inches bosh. This may be said to
be the first decided step towards the great increase in size
which followed, the comparative results being so much in
favour of the large furnace over the original small one that
it soon became an undoubted fact that economy was to be
found in that direCtion. Although the scientific reasons

70 Economy of Fuel. (January, ©

which led to a saving of fuel through an increase in size
were at that time not clearly understood, yet the practical
results obtained were so beneficial that they culminated in
a revolution unparalleled in the blast-furnace history of any
district, in which all the original furnaces and plant were
razed to the ground, and new ones on the now established
improved principles were built in their stead. Furnaces
have been built over 100 feet in height, and some of them
as wide as 30 feet in the bosh; and it is the opinion of those
best competent to judge of the matter, that the useful
maximum of both height and diameter have been attained,
if not exceeded. The object of increasing the size of the
Cleveland furnaces was twofold; first, to increase the make ;
and, secondly, to economise fuel; a third has followed
gratuitously, viz., improvement in quality. The saving of
coke from this cause has been considerable, and may be
put down at from 7 to 8 cwts. of coke per ton of iron made.
Mr. Isaac L. Bell, in investigating the causes which led to
this economy of fuel in the larger furnaces, discovered that
in a furnace one or two combinations are possible—that of
one equivalent of carbon uniting with one or with two
equivalents of oxygen; and that in the latter case as much
heat is developed by 20 cwts. as is done by 71°14 cwts.
when the carbon only unites with one equivalent of oxygen.

The cause of the saving in fuel in large furnaces is two-
fold; first, by the interception of a considerable portion
of the heat formerly carried away in the gases—the products
of combustion of the old furnaces; and, secondly owing to
a better state of oxidation or combustion of the carbon,—a
state of things proved by a great number of chemical
analyses of the gases themselves as they leave the furnaces.
Mr. Bell has also proved that no subsequent additions to
the size of the furnace, beyond a certain point, has been
attended with anything like the saving which accompanied
the first steps in that direction; and that this is due to the
fact that the escaping gases have, by such increase in
dimensions, been deprived of nearly all the heat they can
be made to surrender for use in the furnace; and that the
chemical action in a furnace of about 12,000 feet is as
perfect, so far as numerous analyses of the gases could
indicate, as it is in a furnace of 25,000 cubic feet.

Next to the increased size of the furnace, the principal
cause of economy in fuel in the manufacture of iron is the
improved temperature of blast at the tuyeres, which has
been increased up to 1400. In order to obtain this

1874.! Economy of Fuel. 71

temperature, heating-stoves are employed, consisting most
generally of a series of iron pipes within a furnace, through
which the heat for the blast is drawn. The highest tempe-
rature and the best results have, however, been obtained
with Whitwell’s hot-blast fire-brick stoves, by the use of
which, at Consett, iron has been made with 17 cwts. 2 qrs.
of coke per ton, the blast being at a pressure of 3 lbs. per
inch, and the temperature about 1400°. With an increased
pressure of blast to 4 lbs., and a decrease in temperature to
I200, an increased production of pig-iron was the result,
but the consumption of coke rose to 19 cwts. 2 qrs. per ton.

Under the most economical system of working, with open-
topped furnaces, an enormous amount of fuel is wasted by
the escape of the vapours of combustion, many of them
only half consumed at a high temperature. So early as the
beginning of the present century (1811), the important
practical problem of the utilisation of the waste gas of iron-
smelting furnaces was solved in a satisfactory manner in
France; but upwards of five and twenty years elapsed
before it began to attract the serious attention of iron-
masters in Great Britain or on the Continent of Europe.
The first attempts made in this country were exceedingly
crude, and much of the carbonic oxide was allowed to
escape unburnt into the air, by which an enormous amount
_of heat, capable of being developed by the combustion of
that gas, was lost. The calorific effect of the waste gas is
due partly to its sensible heat, and partly to the heat
developed by its combustion in contact with atmospheric
air. In some furnaces, the gas is taken off through several
circular openings ata short distance below the level of the
solid contents of the furnace, their exhaustion being effected
by means of a high stack. In others, there is an annular
passage or flue near the mouth, extending all round, and
communicating with the interior by several short passages,
and in this case, also, the aid of a stack is required for ex-
haustion. The most general method is, however, to close
the top of the furnace with a ‘‘ cup and cone.”

We must not close our account of economy of fuel in the
blast-furnace without some reference to Ferrie’s self-coking
blast-furnace. In considering the problem of utilising the
gases escaping from blast-furnaces worked with raw coal, it
occurred to Mr. Ferrie that much of the difficulty would be
overcome if the coal could be coked in the furnace in some-
what the same way as it is coked in gas retorts. In the
application of these ideas to a large furnace at the Monkland
Works, the mouth of the furnace is closed by a bell and

72 Economy of Fuel. (January,

hopper, and the gases are led off to the blast-heating stoves
in the usual way. The upper part of the furnace, for
a depth of 20 feet below the space required for the bell and
cone, is divided into four compartments by vertical walls
supported on arches, and radiating from the centre. These
division walls, by causing additional frictional resistance to
be opposed to the descent of the materials, relieve the coke
formed of a portion of its load, but their main object is to
enable the coking of the coal to be performed in the upper
part of the furnace. The economic results obtained with
this furnace have been most satisfactory, and they were thus
described by Mr. Ferrie himself to the Iron and Steel
Institute, at their meeting in March, 1871:

‘“‘In the Lanarkshire district, the quantity of coal
required in the manufacture of a ton of No. I pig-iron
ranges from 50 to 52 cwts. in the furnace, whereas, in this
furnace, a ton of the same quality can be produced with
32 to 36 cwts., effecting a saving in coal of nearly a ton to
the ton of iron made. In ores, the saving in this furnace
will be about 2} cwts. per ton of iron.”

The quantity of gas drawn off from the furnace is found
to be greatly in excess of that required for heating the blast
and raising steam for the blowing engines ; but where works
for the production of finished iron are annexed to the blast-
furnaces, ready means may be found for utilising this excess
of gas.

The next subject for consideration is the economy of fuel
hitherto attained in the manufacture of iron and steel.
Before the introduction of the puddling process, the conver-
sion of cast-iron into malleable or wrought-iron was always
effected in a finery or hearth, in which the metal was melted
in contact with the solid fuel, and so exposed to the highly
oxidising action of a blast of atmospheric air. Dr. Siemens,
in a lecture delivered to the operative classes of Bradford,
on behalf of the British Association, in September last,
remarked that in the metallurgical furnace there is great
room for improvement, the actual fuel consumed in heating
a ton of iron up to the welding point, or in melting a ton of
steel, being more in excess of the theoretical quantity
required for those purposes than is the case with regard to
the production of steam power or to domestic consumption.
Taking the specific heat of iron at 114, and the welding
heat at 2700 degrees F., it would require 307 heat units
to heat 1 lb. of iron. A pound of pure carbon develops
14,500 units of heat, a pound of common coal 12,000, and
therefore 1 ton of coal should bring 39 tons of iron up to the

1874.] Economy of Fuel. 73

welding point. In an ordinary re-heating furnace, a ton of
coal heats only 12 tons of iron, and therefore produces
only one twenty-third part of the maximum theoretic effect.
In melting one ton of steel in pots, 24 tons of coke are con-
sumed; and, taking the melting point of steel at 3600 F.,
the specific heat at o*11g, it takes 428 heat units to melt
a pound of steel; and, taking the heat-producing power
of common coke also at 12,000 units, I ton of coke ought
to be able to melt 28 tons of steel. ‘The Sheffield pot steel
melting-furnace, therefore, only utilises one-seventieth part
of the theoretical heat developed in the combustion.
Several methods are now in use whereby greater economy
in fuel results, but we shall not now do more than
give special notice to one of these, as the object of
fac present article is not so. much to refer to all
methods of economising fuel, but rather to point out
to what extent economy has been attained in various
branches of consumption. We propose here merely to
specify the Siemens’s regenerative furnace, which is now too
well known to require any detailed description, and by the
use of which a ton of steel is melted with 12 cwts. of small
coal, whereas in the ordinary furnace at Sheffield, about
3 tons of Durham coke are necessary to accomplish the
sameend. In this one operation, therefore, in the process
of steel manufacture, a saving of four-fifths of the fuel
ordinarily employed is capable of being effected.

Turning now to Mr. Bessemer’s system of steel manufac-
ture, we find where 33 tons of coke are ordinarily used per
ton of steel, 3 cwts. only is required for his process; and we
find that gentleman stating, in evidence, before the Coal
Commission of 1871, that ‘“‘if we take the present produc-
tion of cast steel, in this country, by my process, at 150,000
tons a year, we should have a saving of a little over half a
million tons of coke in that time, representing, of course, its
proportion of coal, the amount being greater or less according
to the purity of the coal employed.”

In estimating the waste of fuel under steam boilers, it is
necessary to remember that in burning 1 1b. of carbon in
the presence of free oxygen, carbonic acid is produced, and
14,500 units of heat are liberated. Each unit of heat is
convertible into 774 units of force or mechanical energy ;
and hence, 1 lb. of carbon represents really 11,223,000 units
of potential energy ; that is to say, the mechanical energy
set free in the combustion of 1 lb. of pure carbon is the same
that would be required to raise 11,223,000 pounds weight one
foot high, or as would sustain the work which we call

VOL. IV. (N.S.) L

74 Economy of Fuel. ‘[January,

a horse power during five hours thirty-three minutes.
Practically, however, the results obtained fall very far short
of these results. An ordinary non-expansive non-con-
densing engine requires commonly a consumption of from
to lbs. to 12 Ibs. of coal per horse-power per hour, whereas
a good expansive and condensing engine accomplishes the
same amount of work with 2 lbs. of coal per hour.
In order to attain the greatest economy of fuel, used for the
purpose of producing mechanical action, it is first necessary
to provide such an amount of heating surface in the boiler
as shall absorb all the heat produced by combustion, and
transmit it to the water. The beneficial results which are
attained by the greater size of boiler in relation to the coal
burnt and to the horse-power required have been proved by
actual usage, and are not merely matters of calculation. The
Institute of Mechanical Engineers instituted a careful inquiry,
in 1863, into the consumption bythe best engines in the Atlan-
tic Steam Service, and the result showed that it fell in no case
below 43 lbs. per indicated horse-power per hour. Last year
they assembled with the same object in view in Liverpool,
and Mr. Bramwell produced a table, showing that the average
consumption by seventeen good examples of compound
expansive engines did not exceed 2} lbs. per indicated horse-
power per hour. Mr. E. A. Cowper has proved a consumption
not exceeding 1} lbs. per indicated horse-power per hour, ina
compound marine engine constructed with an intermediate
superheating vessel in accordance with his plans. Dr.
Siemens has, however, proved that theoretical perfection
would only be attained if an indicated horse-power were
produced with about 41b. of ordinary steam coal per hour.

Mr. Bramwell, in his address as President of Section G,
at the meeting of the British Association at Brighton, in
1872, bore testimony to the fair duty done by locomotive
engines, which he stated to be due, first, to the fact that,
since the introduction of coal the furnaces have been to a
considerable extent gas furnaces, with a free admission of
air through open fire doors to the surface of the fuel; and,
secondly, to the fact that the boilers have large absorbing
powers. In marine engines there has, within the last ten
years, been an enormous saving. The old fashioned engine,
working at 20 lb. steam and with injector condensers, is
being abandoned for engines generally on the compound
cylinder principle, working at 60 lb. and 70 lb. steam, highly
expansive, and fitted with surface condensers; and the result
is a reduction of the consumption of fuel in the same
vessels, on the same voyages, and performed in the same

i

en ce En Ae

1874.] Economy of Fuel. 75

time, of from 40 to 50 per cent of that which was previously
burnt.

Irrespective, however, of other circumstances, a great
waste of fuel may be caused by bad firing; the fire being
kept too thick, or too thin, or irregular. If too thick, the
carbonic acid that is generated by the combustion of the
lower part of the fuel, with which the air first comes in
contact, is changed in its passage through the upper part of
the fuel into carbonic oxide, by absorbing from the fuel a
second equivalent of carbon. If carbonic oxide gas, thus
generated, does not meet with free atmospheric air, at a
suitable temperature in the upper part of the furnace, it
must remain unconsumed, and will pass through the flues
or tubes of the boiler, and make its escape into the air,
carrying with it the valuable unconsumed carbon of the coal
in a gaseous form. And when it is remembered that under
ordinary circumstances every pound of coal burnt into car-
bonic acid is capable of evaporating about 13 lbs. of water
from 212°, while a pound of coal converted into carbonic
oxide is capable of evaporating only 4 lbs. of water, it will be
seen how necessary it is that no mismanagement of the fire
should cause a portion of the fuel thus to escape unburnt up
the chimney.

We have thus pointed out the extent to which, and the
principal means by which economy of fuel has been attained
in the manufacture of iron, and for steam purposes. The
results hitherto attained are, however, still very far from
what theoretically should be practicable; but there can be
little doubt that the same influences which have been at
work to produce established results, will continue to act in
the same direction, and with equally beneficial effects, until
very much better value is obtained out of coal, although it
would be unreasonable to hope that the full theoretical
value should ever be actually attained.; and, indeed, as has
been already shown, such a result would be impossible.

Lastly, a few words with reference to the waste of fuel in
domestic consumption. Nothing could be more extravagantly
absurd, from an economical point of view, than the present
system of open fire-places, and the method of setting them.
From published returns for the year 1872 it appears that,
taking the statistics of the metropolitan district as a guide,
on an average, 12% cwts. of coal is consumed per annum for
each person of the population for domestic services. In the
preceding year the average was slightly higher, but prior to
that it was below that average; so that it appears, in the use
of fuel for domestic purposes, so far from there having been

76 Economy of Fuel. (January,

any attempt at economy, the reverse has been the case, and
this increasing extravagance has only been temporarily
checked by recent high prices.

The common praétice in house building is to put the fire-
grate immediately below and within a chimney; and, as
this chimney is formed of brickwork, by no possibility can
more than the most minute amount of heat be communicated
from the chimney to the room. The main part of the
conducted heat of the fire inevitably goes up the chimney,
and is wasted, leaving the room to be warmed principally, if
not entirely, by the radiated heat. Besides this, it must be
remembered that, ordinarily speaking, no provision is made
by architeéts or builders for the proper supply of air to the
fire-places, and hence arise smoky chimneys and other evils
of the present system. Here, then, is room for much
improvement, and we are glad to perceive that the Society
of Arts is giving its attention seriously to the matter, and it
is to be hoped that some beneficial effects may be the result.
As an evidence of how improved efficiency may be combined
with economy, in this respect we may refer to Captain
Douglas Galton’s fire-grate, on which a paper was read
before the British Association at Norwich, in 1868. ‘This
consists in putting a flue to the upper part of the fire-grate,
which flue passes through a brick chamber formed in the
ordinary chimney ; this chamber being supplied with air from
the exterior of the room by a proper channel, and then the
air, after being heated in conta¢t with the flue in the
chamber, escapes into the room by openings near the ceiling,
so that the room is supplied with a copious volume of warm
fresh air, thus doing away with all tendency to draughts
from the doors and windows, and furnishing an ample supply
for the purposes of ventilation and combustion.

1874.] C77)

wait NOTES OF AN ENQUIRY INTO THE
PHENOMENA CALLED SPIRITUAL,
DURING THE YEARS 1870-73.

By WILLIAM CROOKES, F.R.S., &c.

oe
Fhe a traveller exploring some distant country, the
wonders of which have hitherto been known only
through reports and rumours of a vague or distorted
character, so for four years have I been occupied in pushing
an enquiry into a territory of natural knowledge which
offers almost virgin soil to a scientific man. As the traveller
sees in the natural phenomena he may witness the action of
forces governed by natural laws, where others see only the
Capricious intervention of offended gods, so have I endea-
voured to trace the operation of natural laws and forces,
where others have seen only the agency of supernatural
beings, owning no laws, and obeying no force but their own
free will. As the traveller in his wanderings is entirely
dependent on the goodwill and friendliness of the chiefs
and the medicine men of the tribes amongst whom he
sojourns, so have I not only been aided in my enquiry in a
marked degree by some of those who possess the peculiar
powers I have sought to examine, but have also formed
firm and valued friendships amongst many of the recognised
leaders of opinion, whose hospitalities I have shared. As
the traveller sometimes sends home, when opportunity offers,
a brief record of progress, which record, being necessarily
isolated from all that has led up to it, is often received with
disbelief or ridicule, so have I on two occasions selected
and published what seemed to be a few striking and definite
facts; but having omitted to describe the preliminary stages
necessary to lead the public mind up to an appreciation of
the phenomena and to show how they fitted into other
observed facts, they were also met, not only with incredulity,
but with no little abuse. And, lastly, as the traveller, when
his exploration is finished and he returns to his old
associates, colle¢ts together all his scattered notes, tabulates
them, and puts them in order ready to be given to the world
as a connected narrative, so have I, on reaching this stage
of the enquiry, arranged and put together all my discon-
nected observations ready to place before the public in the
form of a volume.
The phenomena I am prepared to attest are so extra-
ordinary and so directly oppose the most firmly rooted

78 Notes of an Enquiry into the [January,

articles of scientific belief—amongst others, the ubiquity and
invariable action of the law of gravitation—that, even now,
on recalling the details of what I witnessed, there is an
antagonism in my mind between reason, which pronounces
it to be scientifically impossible, and the consciousness that
my senses, both of touch and sight,—and these corroborated,
as they were, by the senses of all who were present,—are
not lying witnesses when they testify against my preconcep-
tions.*

But the supposition that there is a sort of mania or
delusion which suddenly attacks a whole roomful of in-
telligent persons who are quite sane elsewhere, and that
they all concur to the minutest particulars, in the details
of the occurrences of which they suppose themselves to be
witnesses, seems to my mind more incredible than even the
facts they attest.

The subject is far more difficult and extensive than it
appears. Four years ago I intended only to devote a
leisure month or two to ascertain whether certain marvellous
occurrences I had heard about would stand the test of close
scrutiny. Having, however, soon arrived at the same
conclusion as, I may say, every impartial enquirer, that
there was ‘‘ something in it,” I could not, as a student
of nature’s laws, refuse to follow the enquiry wheresoever
the facts might lead. Thus a few months have grown into
a few years, and were my time at my own disposal it would
probably extend still longer. But other matters of scientific
and praCtical interest demand my present attention; and,
inasmuch as J cannot afford the time requisite to follow the
enquiry as it deserves, and as I am fully confident it will
be studied by scientific men a few years hence, and as my
opportunities are not now as good as they were some time
ago, when Mr. D. D. Home was in good health, and Miss

* The following remarks are so appropriate that I cannot forbear quoting
them. They occur in a private letter from an old friend, to whom I had sent
an account of some of these occurrences. The high position which he holds
in the scientific world renders doubly valuable any opinion he expresses on the
mental tendencies of scientific men. ‘‘ Any intellectual reply to your facts I
cannot see. Yet it is a curious fact that even I, with all my tendency
and desire to believe spiritualistically, and with all my faith in your power
of observing and your thorough truthfulness, feel as if I wanted to see for
myself; and it is quite painful to me to think how much more proof I want.
Painful, I say, because I see that it is not reason which convinces a man,
unless a fact is repeated so frequently that the impression becomes like a habit
of mind, an old acquaintance, a thing known so long that it cannot be doubted.
This is a curious phase of man’s mind, and it is remarkably strong in scientific
men—stronger than in others, I think. For this reason we must not always
call a man dishonest because he does not yield to evidence for a long time.
The old wall of belief must be broken down by much battering.”

= oe itm th me ip ae a

oe wtih

1874.] Phenomena called Spiritual. 79

Kate Fox (now Mrs. Jencken) was free from domestic and
maternal occupations, I feel compelled to suspend further
investigation for the present.

To obtain free access to some persons abundantly
endowed with the power I am experimenting upon, now
involves more favour than a scientific investigator should
be expected to make of it. Spiritualism amongst its
more devout followers is a religion. The mediums, in
‘many cases young members of the family, are guarded
with a seclusion and jealousy which an outsider can
penetrate with difficulty. Being earnest and conscien-
tious believers in the truth of certain do¢trines which they
hold to be substantiated by what appear to them to be
miraculous occurrences, they seem to hold the presence of
scientific investigation as a profanation of the shrine. Asa
personal favour I have more than once been allowed to be
present at meetings that presented rather the form of a
religious ceremony than of a spiritualistic séance. But
to be admitted by favour once or twice, as a stranger
might be allowed to witness the Eleusinian mysteries, or a
Gentile to peep within the Holy of Holies, is not the way to
ascertain facts and discover laws. To gratify curiosity is
one thing; to carry on systematic researchis another. Iam
seeking the truth continually. Ona few occasions, indeed, I
have been allowed to apply tests and impose conditions ; but
only once or twice have I been permitted to carry off the
priestess from her shrine, and in my own house, surrounded
by my own friends, to enjoy opportunities of testing the
phenomena I had witnessed elsewhere under less conclusive
-conditions.* My observations on these cases will find their
due place in the work I am about to publish.

Following the plan adopted on previous occasions,—a plan
which, however much it offended the prejudices of some
critics, I have good reason to know was acceptable to the
readers of the ‘‘ Quarterly Journal of Science,”’—I in-
tended to embody the results of my labour in the form of
one or two articles for this journal. However, on going
over my notes, I find such a wealth of faéts, such a super-
abundance of evidence, so overwhelming a mass of tes-
timony, all of which will have to be marshalled in order,
that I could fill several numbers of the ‘‘Quarterly.” I must

* In this paper I give no instances and use no arguments drawn from these
exceptional cases. Without this explanation it might be thought that the
immense number of facts I have accumulated were principally obtained on the
few occasions here referred to, and the objeéion would naturally arise of
insufficiency of scrutiny from want of time.

80 Notes of an Enquiry into the [January,

therefore be content on this occasion with an outline only of
my labours, leaving proofs and full details to another
occasion.

My principal object will be to place on record a series of
actual occurrences which have taken place in my own house,
in the presence of trustworthy witnesses, and under as
strict test conditions as I could devise. Every faét which I
have observed is, moreover, corroborated by the records of
independent observers at other times and places. It will be
seen that the facts are of the most astounding character, and
seem utterly irreconcilable with all known theories of modern
science. Having satisfied myself of their truth, it would be
moral cowardice to withhold my testimony because my pre-
vious publications were ridiculed by critics and others who
knew nothing whatever of the subject, and who were too pre-
judiced to see and judge for themselves whether or not there
was truth in the phenomena; I shall state simply what
I have seen and proved by repeated experiment and test, and
‘“T have yet to learn that it is irrational to endeavour to dis-
cover the causes of unexplained phenomena.”

At the commencement, I must correct one or two errors
which have taken firm possession of the public mind. One
is that darkness is essential to the phenomena. ‘This is by
no means the case. Except where darkness has been a neces-
sary condition, as with some of the phenomena of luminous
appearances, and in a fewother instances, everything recorded
has taken place in the light. In the few cases where the
phenomena noted have occurred in darkness I have been
very particular to mention the fact ; moreover some special
reason can be shown for the exclusion of light, or the results
have been produced under such perfect test conditions that
the suppression of one of the senses has not really weakened
the evidence.

Another common error is that the occurrences can be
witnessed only at certain times and places,—in the rooms of
the medium, or at hours previously arranged; and arguing
from this erroneous supposition, an analogy has been
insisted on between the phenomena called spiritual and the
feats of legerdemain by professional ‘‘conjurors” and
‘‘ wizards,” exhibited on their own platform and surrounded
by all the appliances of their art.

To show how far this is from the truth, I need only say
that, with very few exceptions, the many hundreds of fa¢ts
I am prepared to attest,—facts which to imitate by known
mechanical or physical means would baffle the skill of a

1874.] Phenomena called Spiritual. 81

Houdin, a Bosco, or an Anderson, backed with all the
resources of elaborate machinery and the practice of years,—
have all taken place in my own house, at times appointed
by myself, and under circumstances which absolutely pre-
cluded the employment of the very simplest instrumental
aids.

A third error is that the medium must select his own
circle of friends and associates at a séance; that these
friends must be thorough believers in the truth of whatever
doctrine the medium enunciates; and that conditions are im-
posed on any person present of an investigating turn of mind,
which entirely preclude accurate observation and facilitate
trickery and deception. In reply to this, I can state that,
(with the exception of the very few cases to which I have
alluded in a previous paragraph* where, whatever might
have been the motive for exclusiveness, it certainly was
not the veiling of deception), I have chosen my own
circle of friends, have introduced any hard-headed un-
believer whom I pleased, and have generally imposed my
own terms, which have been carefully chosen to prevent
the possibility of fraud. Having gradually ascertained
some of the conditions which facilitate the occurrence of the
phenomena, my modes of conducting these inquiries have
generally been attended with equal, and, indeed, in most
cases with more, success than on other occasions, where,
through mistaken notions of the importance of certain
trifling observances, the conditions imposed might render
less easy the detection of fraud.

I have said that darkness is not essential. It is, however,
a well-ascertained, fa@t that when the force is weak a bright
light exerts an interfering action on some of the phenomena.
The power possessed by Mr. Home is sufficiently strong to
withstand this antagonistic influence ; consequently, he
always objects to darkness at his séances. Indeed, except
on two occasions, when, for some particular experiments of
my own, light was excluded, everything which I have
witnessed with him has taken place in the light. I have
had many opportunities of testing the action of light of
different sources and colours, such as sun-light, diffused day-
light, moon-light, gas, lamp, and candle-light, electric light
from a vacuum tube, homogeneous yellow light, &c. The
interfering rays appear to be those at the extreme end of the
spectrum.

I now proceed to classify some of the phenomena which

* See note on page 79.
VOL: Iv. (N.S.) M

82 Notes of an Enquiry into the (January, ©

have come under my notice, proceeding from the simple to —
the more complex, and briefly giving under each heading an
outline of some of the evidence I am prepared to bring
forward. My readers will remember that, with the excep-
tion of cases specially mentioned, the occurrences have
taken place im my own house, in the light, and with only
private friends present besides the medium. In the con-
templated volume I propose to give in full detail the tests
and precautions adopted on each occasion, with names of —
witnesses. I only briefly allude to them in this article.

Crass a:

The Movement of Heavy Bodies with Contact, but without
Mechanical Exertion.

This is one of the simplest forms of the phenomena observed.
It varies in degree from a quivering or vibration of the room
and its contents to the actual rising into the air of a heavy
body when the hand is placed on it. The retort is obvious
that if people are touching a thing when it moves, they
push it, or pull it, or lift it; I have proved experimentally
that this is not the case in numerous instances, but as
a matter of evidence I attach little importance to this class
of phenomena by itself, and only mention them as a pre-
liminary to other movements of the same kind, but without
contact.

These movements (and indeed I may say the same of
every kind of phenomenon) are generally preceded by a
peculiar cold air, sometimes amounting to a decided wind.
I have had sheets of paper blown about by it, and a ther-
mometer lowered several degrees. On some occasions,
which I will subsequently give more in detail, I have not
detected any actual movement of the air, but the cold has
been so intense that I could only compare it to that felt when
the hand has been within a few inches of frozen mercury.

Crass II.
The Phenomena of Percussive and other Allied Sounds.

The popular name of ‘“‘raps”’ conveys a very erroneous
impression of this class of phenomena. At different times,
during my experiments, I have heard delicate ticks, as with
the point of a pin; a cascade of sharp sounds as from an
induction coil in full work; detonations in the air; sharp
metallic taps; a cracking like that heard when a fri¢tional
machine is at work; sounds like scratching; the twittering
as of a bird, &c.

1874.] Phenomena called Spiritual. 83

These sounds are noticed with almost every medium,
each having a special peculiarity; they are more varied
with Mr. Home, but for power and certainty I have met
with no one who at all approached Miss Kate Fox. For
several months I enjoyed almost unlimited opportunity
of testing the various phenomena occurring in the presence
of this lady, and I especially examined the phenomena of
these sounds. With mediums, generally, it is necessary to
sit for a formal séance before anything is heard; but ,in
the case of Miss Fox it seems only necessary for her to
place her hand on any substance for loud thuds to be heard
in it, like a triple pulsation, sometimes loud enough to be
heard several rooms off. In this manner I have heard
them in a living tree—on a sheet of glass—on a stretched
iron wire—on a stretched membrane—a tambourine—on the
roof of a cab—and on the floor of a theatre. Moreover,
actual contact is not always necessary; I have had these
sounds proceeding from the floor, walls, &c., when the
medium’s hands and feet were held—when she was standing
on a chair—when she was suspended in a swing from the
ceiling—when she was enclosed in a wire cage—and when
she had fallen fainting on a sofa. I have heard them ona
glass harmonicon—I have felt them on my own shoulder
and under my own hands. I have heard them on a sheet of
paper, held between the fingers by a piece of thread passed
through one corner. With a full knowledge of the numerous
theories which have been started, chiefly in America, to
explain these sounds, I have tested them in every way that
I could devise, until there has been no escape from the
conviction that they were true objective occurrences not
produced by trickery or mechanical means.

An important question here forces itself upon the attention.
Are the movements and sounds governed by intelligence? Ata
very early stage of the enquiry, it was seen that the power
producing the phenomena was not merely a blind force, but
was associated with or governed by intelligence: thus the
sounds to which I have just alluded will be repeated a
definite number of times, they will come loud or faint, and
in different places at request; and by a pre-arranged code
of signals, questions are answered, and messages given with
more or less accuracy.

The intelligence governing the phenomena is sometimes
manifestly below that of the medium. It is frequently in
direct opposition to the wishes of the medium: when a
determination has been expressed to do something which
might not be considered quite right, I have known urgent

84 Notes of an Enquiry into the (January,

messages given to induce a reconsideration. The intelligence
is sometimes of such a character as to lead to the belief that
it does not emanate from any person present.

Several instances can be given to prove each of these
statements, but the subject will be more fully discussed
subsequently, when treating of the source of the intelligence.

Crass. III.
The Alteration of Weight of Bodies.

I have repeated the experiments already described in this
Journal, in different forms, and with several mediums. I
need not further allude to them here.

CLASS Ly.

Movements of Heavy Substances when at a Distance from the
Medium.

The instances in which heavy bodies, such as tables,
chairs, sofas, &c. have been moved, when the medium has
not been touching them, are very numerous. _I will briefly
mention a few of the most striking. My own chair has been
twisted partly round, whilst my feet were off the floor. A
chair was seen by all present to move slowly up to the table
from a far corner, when all were watching it; on another
occasion an arm chair moved to where we were sitting, and
then moved slowly back again (a distance of about three
feet) at my request. On three successive evenings a
small table moved slowly across the room, under conditions
which I had specially pre-arranged, so as to answer any
objection which might be raised to the evidence. I have
had several repetitions of the experiment considered by the
Committee of the Diale¢tical Society to be conclusive, viz.,
the movement of a heavy table in full light, the chairs
turned with their backs to the table, about a foot off, and
each person kneeling on his chair, with hands resting over
the backs of the chair, but not touching the table. On one
occasion this took place when I was moving about so as to
see how everyone was placed.

CLASS VV;

The Rising of Tables and Chairs off the Ground, without
Contact with any Person.

A remark is generally made when occurrences of this kind
are mentioned, Why is it only tables and chairs which do
these things? Why is this property peculiar to furniture?
I might reply that I only observe and record facts, and do
not profess to enter into the Why and Wherefore ; but indeed

1874.} Phenomena called Spiritual. 85

it will be obvious that if a heavy inanimate body in an
ordinary dining-room has to rise off the floor, it cannot very
well be anything else but a table or achair. That this pro-
pensity is not specially attached to furniture, I have abundant
evidence ; but, like other experimental demonstrators, the
intelligence or power, whatever it may be, which produces
these phenomena can only work with the materials which
are available.

On five separate occasions, a heavy dining-table rose
between a few inches and 14 feet off the floor, under special
circumstances, which rendered trickery impossible. On
another occasion, a heavy table rose from the floor in full
light, while I was holding the medium’s hands and feet. On
another occasion the table rose from the floor, not only when
no person was touching it, but under conditions which I had
pre-arranged so as to assure unquestionable proof of the
fact.

Cxiass VI.

The Levitation of Human Beings.

This has occurred in my presence on four occasions in
darkness. ‘The test conditions under which they took place
were quite satisfactory, so far as the judgment was con-
cerned ; but ocular demonstration of such a fact is so
necessary to disturb our pre-formed opinions as to “‘ the
naturally possible and impossible,” that I will here only
mention cases in which the deductions of reason were con-
firmed by the sense of sight.

On one occasion I witnessed a chair, with a lady sitting
on it, rise several inches from the ground. On another
occasion, to avoid the suspicion of this being in some way
performed by herself, the lady knelt on the chair in such
manner that its four feet were visible to us. It then rose
about three inches, remained suspended for about ten
seconds, and then slowly descended. At another time two
children, on separate occasions, rose from the floor with their
chairs, in full daylight, under (to me) most satisfactory con-
ditions ; for I was kneeling and keeping close watch upon the
feet of the chair, and observing that no one might touch them.

The most striking cases of levitation which I have
witnessed have been with Mr. Home. On three separate
occasions have I seen him raised completely from the floor
of the room. Once sitting in an easy chair, once kneeling
on his chair, and once standingup. On each occasion I had
pull opportunity of watching the occurrence as it was taking
place.

86 Notes of an Enquiry into the (January,

There are at least a hundred recorded instances of Mr.
Home’s rising from the ground, in the presence of as many
separate persons, and I have heard from the lips of the three
witnesses to the most striking occurrence of this kind—the
Earl of Dunraven, Lord Lindsay, and Captain C. Wynne—
their own most minute accounts of what took place. To re-
ject the recorded evidence on this subject is to reject all human
testimony whatever; for no fact in sacred or profane history
is supported by a stronger array of proofs.

The accumulated testimony establishing Mr. Home’s
levitations is overwhelming. It is greatly to be desired
that some person, whose evidence would be accepted as
conclusive by the scientific world—if indeed there lives
a person whose testimony im favour of such phenomena
would be taken—would seriously and patiently examine
these alleged facts. Most of the eye-witnesses to these
levitations are now living, and would, doubtless, be willing
to give their evidence. But, in a few years, such direct
evidence will be difficult, if not impossible, to be obtained.

Crass -VaL.

Movement of Various Small Articles without Contact with any
Person.

Under this heading I propose to describe some special
phenomena which I have witnessed. I can do little more
here than allude to some of the more striking facts, all of
which, be it remembered, have occurred under circum-
stances that render trickery impossible. But it is idle to
attribute these results to trickery, for I would again remind
my readers that what I relate has not been accomplished at
the house of a medium, but in my own house, where pre-
parations have been quite impossible. A medium,walking into
my dining-room, cannot, while seated in one part of the
room with a number of persons keenly watching him, by
trickery make an accordion play in my own hand when I hold
it keys downwards, or cause the same accordion to float
about the room playing all the time. He cannot introduce
machinery which will wave window-curtains or pull up
Venetian blinds 8 feet off, tie a knot in a handkerchief and
place it ina far corner of the room, sound notes on a distant
piano, cause a card-plate to float about the room, raise a
water-bottle and tumbler from the table, make a coral neck-
lace rise on end, cause a fan to move about and fan the
company, or set in motion a pendulum when enclosed in a
glass case firmly cemented to the wall.

1874.] Phenomena called Spiritual. 87

Crass VIII.
Luminous Appearances.

These, being rather faint, generally require the room to be
darkened. I need scarcely remind my readers again that,
under these circumstances, I have taken proper precautions
to avoid being imposed upon by phosphorised oil or other
means. Moreover, many of these lights are such as I have
tried to imitate artificially, but cannot.

Under the strictest test conditions, I have seen a solid
self-luminous body, the size and nearly the shape of a
turkey’s egg, float noiselessly about the room, at one time
higher than any one present could reach standing on
tiptoe, and then gently descend to the floor. It was
visible for more than ten minutes, and before it faded away
it struck the table three times with a sound like that
of a hard, solid body. During this time the medium
was lying back, apparently insensible, in an easy chair.

I have seen luminous points of light darting about and
settling on the heads of different persons; I have had
questions answered by the flashing of a bright light a
desired number of times in front of my face. I have
seen sparks of light rising from the table to the ceiling, and
again falling upon the table, striking it with an audible
sound.- I have had an alphabetic communication given by
luminous flashes occurring before me in the air, whilst my
hand was moving about amongst them. I have seen a lumi-
nous cloud floating upwards to a picture. Under the strictest
test conditions, I have more than once had a solid, self-
luminous, crystalline body placed in my hand by a hand which
did not belong to any person in the room. In the light, I
have seen a luminous cloud hover over a heliotrope on a
side table, break a sprig off, and carry the sprig to a lady;
and on some occasions I have seen a similar luminous cloud
visibly condense to the form of a hand and carry small
objects about. These, however, more properly belong to the
next class of phenomena.

CLASS LX:

The Appearance of Hands, either Self-Luminous or Visible by
Ordinary Light.

The forms of hands are frequently felt at dark séances, or
under circumstances where they cannot be seen. More
rarely I have seen the hands. I will here give no instances
in which the phenomenon has occurred in darkness, but will

gy

88 Notes of an Enquiry into the (January,

simply select a few of the numerous instances in which I
have seen the hands in the light.

A beautifully-formed small hand rose up from an opening
in a dining-table and gave me a flower; it appeared and
then disappeared three times at intervals, affording me
ample opportunity of satisfying myself that it was as real
in appearance as my own. ‘This occurred in the light in
my own room, whilst I was holding the medium’s hands and
feet.

On another occasion, a small hand and arm, like a baby’s,
appeared playing about a lady who was sitting next to me.
It then passed to me and patted my arm and pulled my
coat several times.

At another time, a finger and thumb were seen to pick the
petals from a flower in Mr. Home’s button-hole, and lay
them in front of several persons who were sitting near
him.

A hand has repeatedly been seen by myself and others
playing the keys of an accordion, both of the medium’s
hands being visible at the same time, and sometimes being
held by those near him.

The hands and fingers do not always appear to me to be
solid and life-like. Sometimes, indeed, they present more
the appearance of a nebulous cloud partly condensed into
the form of a hand. This is not equally visible to all
present. For instance, a flower or other small object is
seen to move; one person present will see a luminous cloud
hovering over it, another will detect a nebulous-looking
hand, whilst others will see nothing at all but the moving
flower. I have more than once seen, first an object move,
then a luminous cloud appear to form about it, and, lastly,
the cloud condense into shape and become a perfectly-
formed hand. At this stage, the hand is visible to all present.
It isnot always a mere form, but sometimes appears perfectly
life-like and graceful, the fingers moving and the flesh appa-
rently as human as that of any in the room. At the wrist,
or arm, it becomes hazy, and fades off into a luminous
cloud.

To the touch, the hand sometimes appears icy cold and
dead, at other times, warm and life-like, grasping my own
with the firm pressure of an old friend.

I have retained one of these hands in my own, firmly
resolved not to let it escape. There was no struggle
or effort made to get loose, but it gradually seemed to re-
solve itself into vapour, and faded in that manner from my

grasp.

1874.] Phenomena called Spiritual. 89

Crass X.
Direct Writing.

This is the term employed to express writing which is not
produced by any person present. I have had words and
messages repeatedly written on privately-marked paper,
under the most rigid test conditions, and have heard the
pencil moving over the paper in thedark. The conditions—
pre-arranged ‘by myself—have been so strict as to be equally
convincing to my mind as if I had seen the written
characters formed. But as space will not allow me to enter
into full particulars, I will merely sele¢t two instances in
which my eyes as well as ears were witnesses to the opera-
tion.

The first instance which I shall give took place, it is true,
at a dark séance, but the result was not less satisfactory on
that account. I was sitting next to the medium, Miss Fox,
the only other persons present being my wife and a lady rela-
tive,and I was holding the medium’s two hands in one of mine,
whilst her feet were resting on my feet. Paper was on the
table before us, and my disengaged hand was holding a
pencil.

A luminous hand came down from the upper part of the
room, and after hovering near me for a few seconds, took the
pencil from my hand, rapidly wrote on a sheet of paper,
threw the pencil down, and then rose up over our heads,
gradually fading into darkness.

My second instance may be considered the record of a
failure. ‘‘ A good failure often teaches more than the most
successful experiment.”” It took place in the light, in my
own room, with only a few private friends and Mr. Home
present. Several circumstances, to which I need not further
allude, had shown that the power that evening was strong.
I therefore expressed a wish to witness the actual production
of a written message such as I had heard described a short
time before by a friend. Immediately an alphabetic com-
munication was made as follows—‘‘ We will try.” A pencil
and some sheets of paper had been lying on the centre of the
table ; presently the pencil rose up on its point, and after
advancing by hesitating jerks to the paper fell down. It
then rose and again fell. A third time it tried, but with no
better result. After three unsuccessful attempts, a small
wooden lath, which was lying near upon the table, slid towards
the pencil, and rose a few inches from the table; the pencil
rose again, and propping itself against the lath, the two
together made an effort tomark the paper. It fell, and then

VOL. IV. (N.S.) N

go Notes of an Enquiry into the (January,

a joint effort was again made. After a third trial the lath
gave it up and moved back to its place, the pencil lay as it
fell across the paper, and an alphabetic message told us
—‘‘ We have tried to do as you asked, but our power is
exhausted.”

CLASS 0.
Phantom Forms and Faces.

These are the rarest of the phenomena I have witnessed.
The conditions requisite for their appearance appear to be
so delicate, and such trifles interfere with their produétion,
that only on very few occasions have I witnessed them under
satisfactory test conditions. I will mention two of these
Cases.

In the dusk of the evening, during a séance with Mr. Home
at my house, the curtains of a window about eight feet from
Mr. Home were seen to move. A dark, shadowy, semi-
transparent form, like that of a man, was then seen by all
present standing near the window, waving the curtain with
his hand. As we looked, the form faded away and the
curtains ceased to move.

The following is a still more striking instance. As in the
former case, Mr. Home was the medium. A phantom form
came from a corner of the room, took an accordion in its hand,
and then glided about the room playing the instrument.
The form was visible to all present for many minutes,
Mr. Home also being seen at the same time. Coming rather
close to a lady who was sitting apart from the rest of the
company, she gave a slight cry, upon which it vanished.

Crass Scia.

Special Instances which seem to point to the A gency of an Exterior
Intelligence.

It has already been shown that the phenomena are
governed by an intelligence. It becomes a question of im-
portance as to the source of that intelligence. Is it the
intelligence of the medium, of any of the other persons in
the room, or is it an exterior intelligence? Without
wishing at present to speak positively on this point, I may
say that whilst I have observed many circumstances which
appear to show that the will and intelligence of the medium
have much to do with the phenomena,* I have observed

* I do not wish my meaning to be misunderstood. What I mean is, not
that the medium’s will and intelligence are actively employed in any conscious
or dishonest way in the production of the phenomena, but that they sometimes
appear to act in an unconscious manner.

q

1874.] Phenomena called Spiritual. gI

some circumstances which seem conclusively to point to the
agency of an outside intelligence, not belonging to any
human being in the room. Space does not allow me to
give here all the arguments which can be adduced to prove
these points, but I will briefly mention one or two circum-
stances out of many.

I have been present when several phenomena were going
on at the same time, some being unknown to the medium.
I have been with Miss Fox when she has been writing a
message automatically to one person present, whilst a mes-
sage to another person on another subject was being given
alphabetically by means of “‘ raps,” and the whole time she
was conversing freely with a third person on a subject
totally different from either. Perhaps a more striking
instance is the following :—

During a séance with Mr. Home, a small lath, which I
have before mentioned, moved across the table to me, in the
light, and delivered a message to me by tapping my hand;
I repeating the alphabet, and the lath tapping me at the
right letters. The other end of the lath was resting on the
table, some distance from Mr. Home’s hands.

The taps were so sharp and clear, and the lath was
evidently so well under control of the invisible power which
was governing its movements, that I said, ‘‘ Can the intel-
ligence governing the motion of this lath change the
character of the movements, and give me a telegraphic
message through the Morse alphabet by taps on my hand?”
(I have every reason to believe that the Morse code was
- quite unknown to any other person present, and it was only

imperfectly known to me). Immediately I said this, the
character of the taps changed, and the message was con-
tinued in the way I had requested. ‘The letters were given
too rapidly for me to do more than catch a word here and
there, and consequently I lost the message; but I heard
sufficient to convince me that there was a good Morse
Operator at the other end of the line, wherever that
might be.

Another instance. A lady was writing automatically by
means of the planchette. I was trying to devise a means
of proving that what she wrote was not due to ‘ uncon-
scious cerebration.” The planchette, as it always does,
insisted that, although it was moved by the hand and arm
of the lady, the intelligence was that of an invisible being
who was playing on her brain as on a musical instrument,
and thus moving her muscles. I therefore said to this
intelligence, ‘‘Can you see the contents of this room ?”

92 Notes of an Enquiry into the |January,

“Yes,” wrote the planchette. ‘‘ Can you see to read this )

newspaper?” said I, putting my finger on a copy of the
Times, which was on a table behind me, but without looking
at it. ‘‘ Yes’’ was the reply of the planchette. ‘* Well,”
I said, “‘if you can see that, write the word which is
now covered by my finger, and I will believe you.” The
planchette commenced to move. Slowly and with great
difficulty, the word ‘‘ however” was written. I turned
round and saw that the word ‘‘ however” was covered by the
tip of my finger.

I had purposely avoided looking at the newspaper when
I tried this experiment, and it was impossible for the lady,
had she tried, to have seen any of the printed words, for she
was sitting at one table, and the paper was on another table
behind, my body intervening.

Crass XIII.
Miscellaneous Occurrences of a Complex Character.

Under this heading I propose to give several occurrences
which cannot be otherwise classified owing to their complex
character. Out of more than a dozen cases, I will select
two. ‘The first occurred in the presence of Miss Kate Fox.
To render it intelligible, I must enter into some details.

Miss Fox had promised to give me a séance at my house
one evening in the spring of last year. Whilst waiting for
her, a lady relative, with my two eldest sons, aged
fourteen and eleven, were sitting in the dining-room where
the séances were always held, and I was sitting by myself,
writing in the library. Hearing a cab drive up and the
bell ring, I opened the door to Miss Fox, and took her
directly into the dining-room. She said she would not
go upstairs, as she could not stay very long, but laid her
bonnet and shawl on a chair in the room. I then went
to the dining-room door, and telling the two boys to go
into the library and proceed with their lessons, I closed the
door behind them, locked it, and (according to my usual
custom at séances) put the key in my pocket.

We sat down, Miss Fox being on my right hand and the
other lady on my left. An alphabetic message was soon
given to turn the gas out, and we thereupon sat in total
darkness, I holding Miss Fox’s two hands in one of mine the
whole time. Very soon, a message was given in the following
words, ‘‘ We are going to bring something to show our
power ;” and almost immediately afterwards, we all heard
the tinkling of a bell, not stationary, but moving about in

1874.} Phenomena called Spiritual. 93

all parts of the room: at one time by the wall, at another
in a further corner of the room, now touching me on the
head, and now tapping against the floor. After ringing
about the room in this manner for fully five minutes, it fell
upon the table close to my hands.

During the time this was going on, no one moved and
Miss Fox’s hands were perfectly quiet. I remarked that it
could not be my little hand-bell which was ringing, for I left
that in the library. (Shortly before Miss Fox came, I had
occasion to refer to a book, which was lying on a corner of a
book-shelf. The bell was on the book, and I put it on one
side to get the book. ‘That little incident had impressed on
my mind the fact of the bell being in the library.) The gas
was burning brightly in the hall outside the dining-room
door, so that this could not be opened without letting light
into the room, even had there been an accomplice in the
house with a duplicate key, which there certainly was not.

I struck a light. There, sure enough, was my own bell
lying on the table before me. I went straight into the
library. A glance showed that the bell was not where it
ought to have been. I said to my eldest boy, ‘‘Do you
know where my little bell is?” ‘‘ Yes, papa,” he replied,
“there it is,” pointing to where I had left it. He looked up
as he said this, and then continued, ‘‘ No—it’s not there, but
it was there a little time ago.” ‘‘ How do you mean ?—has
anyone come in and taken it?” ‘‘ No,” said he, ‘no one
has been in; but I am sure it was there, because when you
sent us in here out of the dining-room, J. (the youngest boy)
began ringing it so that I couid not go on with my lessons,
and I told him to stop.” J. corroborated this, and said that,
after ringing it, he put the bell down where he had found it.

The second circumstance which I will relate occurred
in the light, one Sunday evening, only Mr. Home and
members of my family being present. My wife and I had
been spending the day in the country, and had brought
home a few flowers we had gathered. On reaching home,
we gave them to a servant to putthem in water. Mr. Home
came soon after, and we at once proceeded to the dining-
room. As we were sitting down, a servant brought in the
flowers which she had arranged in a vase. I placed it in
the centre of the dining-table, which was without a
cloth. ‘This was the first time Mr. Home had seen these
flowers.

After several phenomena had occurred, the conversation
turned upon some circumstances which seemed only ex-
plicable on the assumption that matter had actually passed

94 Notes of an Enquiry into the [January,

through a solid substance. Thereupon a message was given
by means of the alphabet: ‘‘It is impossible for matter to
pass through matter, but we will show you what we can do.”
We waited in silence. Presently a luminous appearance
was seen hovering over the bouquet of flowers, and then, in
full view of all present, a piece of china-grass 15 inches
long, which formed the centre ornament of the bouquet,
slowly rose from the other flowers, and then descended
to the table in front of the vase between it and Mr. Home.
It did not stop on reaching the table, but went straight
through it, and we all watched it till it had entirely
passed through. Immediately on the disappearance of the
grass, my wife, who was sitting near Mr. Home, saw a hand
come up from under the table between them, holding the
piece of grass. It tapped her on the shoulder two or three
times with a sound audible to all, then laid the grass on the
floor, and disappeared. Only two persons saw the hand,
but all in the room saw the piece of grass moving about as
I have described. During the time this was taking place,
Mr. Home’s hands were seen by all to be quietly resting on
the table in front of him. ‘The place where the grass dis-
appeared was 18 inches from his hands. The table wasa
telescope dining-table, opening with a screw; there was no
leaf in it, and the junction of the two sides formed a narrow
crack down the middle. The grass had passed through this
chink, which I measured, and found to be barely 3th inch
wide. The stem of the piece of grass was far too thick to
enable me to force it through this crack without injuring it,
yet we had all seen it pass through quietly and smoothly ;
and on examination, it did not show the slightest signs of
pressure or abrasion.

THEORIES TO ACCOUNT FOR THE PHENOMENA OBSERVED.

First Theory—The phenomena are all the results of
tricks, clever mechanical arrangements, or legerdemain; the
mediums are impostors, and the rest of the company fools.

It is obvious that this theory can only account for a very
small proportion of the facts observed. I am willing to
admit that some so-called mediums of whom the public
bave heard much are arrant impostors who have taken
advantage of the public demand for spiritualistic excitement
to fill their purses with easily earned guineas ; whilst others
who have no pecuniary motive for imposture are tempted
to cheat, it would seem, solely by a desire for notoriety. I
have met with several cases of imposture, some very ingenious,
others so palpable, that no person who has witnessed the

1874.] Phenomena called Spiritual. 95

genuine phenomena could be taken in by them. An enquirer
into the subject finding one of these cases at his first initia-
tion is disgusted with what he detects at once to be an im-
posture ; and he not unnaturally gives vent to his feelings,
privately or in print, by a sweeping denunciation of the whole
genus ‘‘medium.” Again, with a thoroughly genuine medium,
the first phenomena which are observed are generally slight
movements of the table, and faint taps under the medium’s
hands or feet. These of course are quite easy to be imitated
by the medium, or anyone at the table. If, as sometimes
occurs, nothing else takes place, the sceptical observer goes
away with the firm impression that his superior acuteness
detected cheating on the part of the medium, who was
consequently afraid to proceed with any more tricks in his
presence. He, too, writes to the newspapers exposing the
whole imposture, and probably indulges in moral senti-
ments about the sad spectacle of persons, apparently intel-
ligent, being taken in by imposture which he detected at once.

There is a wide difference between the tricks of a pro-
fessional conjurer, surrounded by his apparatus, and aided
by any number of concealed assistants and confederates,
deceiving the senses by clever sleight of hand on his own
platform, and the phenomena occurring in the presence of
Mr. Home, which take place in the light, in a private room
that almost up to the commencement of the séance has
been occupied as a living room, and surrounded by private
friends of my own, who not only will not countenance the
slightest deception, but who are watching narrowly every
thing that takes place. Moreover, Mr. Home has frequently
been searched before and after the séances, and he always
offers to allow it. During the most remarkable occurrences
I have occasionally held both his hands, and placed my feet
on his feet. Onno single occasion have I proposed a modifi-
cation of arrangements for the purpose of rendering trickery
less possible which he has not at once assented to, and
frequently he has himself drawn attention to tests which
might be tried.

I speak chiefly of Mr. Home, as he is so much more
powerful than most of the other mediums I have experi-
mented with. But with all I have taken such precautions
as place trickery out of the list of possible explanations.

Be it remembered that an explanation to be of any value
must satisfy all the conditions of the problem. It is not
enough for a person, who has perhaps seen only a few of
the inferior phenomena, to say “I suspect it was all

cheating,” or, ““I saw how some of the tricks could be
done,”

96 Notes of an Enquiry into the (January,

Second Theory.—The persons at a séance are the victims of
a sort of mania or delusion, and imagine phenomena
to occur which have no real obje¢tive existence.

Third Theory.—The whole is the result of conscious or
unconscious cerebral action.

These two theories are evidently incapable of embracing
more than a small portion of the phenomena, and they are
improbable explanations for even those. They may be
dismissed very briefly.

I now approach the ‘‘ Spiritual’ theories. It must be
remembered that the word ‘“‘ spirits’ is used in a very vague
sense by the generality of people.

Fourth Theory.—The result of the spirit of the medium,
perhaps in association with the spirits of some or all of
the people present.

Fifth Theory—The actions of evil spirits or devils,
personifying who or what they please, in order to undermine
Christianity and ruin men’s souls.

Sixth Theory.— The actions of a separate order of beings,
living on this earth, but invisible and immaterial to us.
Able, however, occasionally to manifest their presence.
Known in almost all countries and ages as demons (not
necessarily bad), gnomes, fairies, kobolds, elves, goblins,
Puck, &c.

Seventh Theory.—The actions of departed human beings—
the spiritual theory par excellence.

Eighth Theory.—(The Psychic Force Theory).—This is a
necessary adjunct to the 4th, 5th, 6th, and 7th theories,
rather than a theory by itself.

According to this theory the ‘‘ medium,” or the circle of
people associated together as a whole, is supposed to
possess a force, power, influence, virtue, or gift, by means of
which intelligent beings are enabled to produce the phe-
nomena observed. What these intelligent beings are is a
subject for other theories.

It is obvious that a ‘‘medium’” possesses a something
which is not possessed by an ordinary being. Give this
something aname. Call it “x” if you like. Mr. Serjeant
Cox calls it Psychic Force. ‘There has been so much mis-
understanding on this subject that I think it best tu give the
following explanation in Mr. Serjeant Cox’s own words :—

‘“The Theory of Psychic Force is in itself merely the recog-
nition of the now almost undisputed fact that under certain
conditions, as yet but imperfectly ascertained, and within a
limited, but as yet undefined, distance from the bodies of
certain persons having a special nerve organisation, a Force
operates by which, without muscular contact or connection,

1874.] Phenomena called Spiritual. 97

action at a distance is caused, and visible motions and audible
sounds are produced in solid substances. As the presence
of such an organisation is necessary to the phenomenon, it
is reasonably concluded that the Force does, in some manner
as yet unknown, proceed from that organisation. As the
organism is itself moved and directed within its structure by
a Force which either is, or is controlled by, the Soul,
Spirit, or Mind (call it what we may) which constitutes the
individual being we term ‘the Man,’ it is anequally reason-
able conclusion that the Force which causes the motions
beyond the limits of the body is the same Force that pro-
duces motion within the limits of the body. And, inasmuch
as the external force is seen to be often dire¢ted by Intelli-
gence, it is an equally reasonable conclusion that the directing
Intelligence of the external force is the same Intelligence
that directs the Force internally. This is the force to which
the name of Psychic Force has been given by me as
properly designating a force which I thus contend to be
traced back to the Soul or Mind of the Man as its source.
But I, and all who adopt this theory of Psychic Force as
being the agent through which the phenomena are produced,
do not thereby intend to assert that this Psychic Force may
not be sometimes seized and directed by some other Intelli-
gence than the Mind of the Psychic. The most ardent
Spiritualists practically admit the existence of Psychic Force
under the very inappropriate name of Magnetism (to which
it has no affinity whatever), for they assert that the Spirits
of the Dead can only do the acts attributed to them by using
the Magnetism (that is, the Psychic Force) of the Medium.
The difference between the advocates of Psychic Force
and the Spiritualists consists in this—that we contend
that there is as yet insufficient proof of any other directing
agent than the Intelligence of the Medium, and no proof
whatever of the agency of Spirits of the Dead; while the
Spiritualists hold it as a faith, not demanding further proof,
that Spirits of the Dead are the sole agents in the production
of allthe phenomena. ‘Thus the controversy resolves itself
into a pure question of fact, only to be determined by a
laborious and long-continued series of experiments and an
extensive collection of psychological facts, which should be
the first duty of the Psychological Society, the formation of
which is now in progress.”

VOL. IV. (N.S.) fs)

98 Notices of Books. [January,

NOTICES OF .BOOES:

Lectures on Light. Delivered in America in 1872-1873. By
Joun Tynpatt, LL.D., F.R.S., Professor of Natural
Philosophy in the Royal Institution. London: Longmans,
Green, and Co. 1873. 8vo., 268 pp.

WE are all more or less familiar with the history of Dr. Tyndall’s

recent visit to America. We know that he was invited to that

country to give a course of lectures on Natural Philosophy in
the principal cities of the States, and that he was received
everywhere with open arms. The thirst of the Americans for
science is prodigious ; a considerable scientific taste and literature
is springing up amongst them; their enterprise induces them to
constantly reprint our large works on science; and it will be
remembered that these very lectures of Dr. Tyndall’s were printed
in broadsides, illustrated, and issued, in a newspaper-like form,
at the cost of afewcents. The subject chosen was Light, and,
in the work before us, we have the course of six lectures on that
subject, which Dr. Tyndall delivered in the principle centres of

American thought and progress.

Dr. Tyndall has adopted the plan of giving a history of the
Science of Light, and illustrating each fact as it was discovered.
Thus early in the first lecture we find an account of the law, that
the angle of incidence is equal to the angle of reflection; of
Snell’s Law of the Refraction of Light (1621), sometimes called
‘Descartes’ Law;’ and of Rcemer’s Determination of the
Velocity of Light (1676). ‘Snell’s Law of Refracton,” says our
author, ‘“‘is one of the corner stones of optical science, and
its applications to-day are millionfold. Immediately after its
discovery, Descartes applied it to the explanation of the rainbow.
A beam of solar light falling obliquely upon a raindrop is
refracted on entering the drop, and, on emerging, is again
refracted.” Here follows an explanation of the rainbow, and
the means by which Descartes proved its origin. Next we have
an account of Newton’s Discovery of the Decomposition and
Recomposition of Light, and many illustrations of the discovery ;
then of Achromatism, and the Theory of Colours.

In the second lecture we are introduced to the once rival
conjectures concerning the nature of light:—The ‘* Emission
Theory,” and the ‘‘ Undulatory Theory ;” and here Dr. Tyndall
introduces some very pertinent remarks regarding the conception
of a physical theory, and the necessary use of the imagination
in that form of conception :—‘‘ This conception of physical theory
implies, as you perceive, the exercise of the imagination. Do
not be afraid of this word, which seems to render so many
respectable people, both in the ranks of science and out of them,

1874.] Notices of Books. 99

uncomfortable. That men in the ranks of science should feel
thus is, I think, a proof that they have suffered themselves to be
misled by the popular definition of a great faculty, instead of
observing its operation in their own minds. Without imagination
we cannot take a step beyond the bourne of the mere animal
world, perhaps not even to the edge of this. __ But, in speaking
thus of imagination, I do not mean a riotous power which deals
capriciously with facts, but a well ordered and disciplined power,
whose sole function is to form conceptions which the intellect
imperatively demands. Imagination thus exercised never really
severs itself from the world of fact. This is the storehouse from
which all its pictures are drawn; and the magic of its art consists,
not in creating things anew, but in so changing the magnitude,
position, and other relations of sensible things, as to render them
fit for the requirements of the intellect in the subsensible world.”
The growth of the rival theories is then traced, and the use of
imagination by those who favoured one or the other; we were
unaware that Sir David Brewster did not adopt the undulatory
theory, and certainly unaware that he permitted sentiment to
interfere with his acceptation of a physical theory, as the fol-
lowing passage indicates :—‘‘ In one of my latest conversations
with Sir David Brewster, he said to me that his chief objection
to the undulatory theory of light was, that he could not think the
Creator guilty of so clumsy a contrivance as the filling of space
with ether in order to produce light. This, I may say, is very
dangerous ground, and the quarrel of science with Sir David on
this point, as with many estimable persons on other points, is,
that they profess to know too much about the mind of the
Creator.” The elaborate and most due praise which Tyndall,
and Helmholtz, and many others have ‘bestowed upon Thomas
Young here reappears. But when Dr. Tyndall tells us that
Young was but alittle lower in the intellectual scale than Newton,
and greater than any man of science between Newton’s time and
his own, we cannot, with all possible love for our country and
countrymen, hold with him. For he practically makes Newton
the greatest man of science of all time, and Young second
only to the greatest. Elsewhere he says ‘‘ we trace the progress
of astronomy through Hipparchus and Ptolemy ; and after a long
halt, through Copernicus, Galileo, Tycho Brahe, and Kepler;
while from the high table-land of thought raised by these men
Newton shoots upward like a peak, overlooking all others from
his dominant elevation.” And we would invite comparison
_ between the great and glorious Leonardo da Vinci and the great
and glorious Dr. Thomas Young—men who had many remarkable
points of contact. If no more, at least they should be “bracketed
together” in the list of illustrious men, but we incline to the
greater exaltation of Leonardo da Vinci.

The third lecture treats of the double refracton and polarisation
of light. We may particularly call attention to Fig. 27, and the

100 Notices of Books. (January,

admirably clear explanation which is given of the cause of
refraction by a prism, and of the change of wave-front. The
polarised beam of light is compared, in the matter of its two-
sidedness with the two-endedness of a magnet. The subject of
polarisation, and the chromatic phenomena which accompany it,
is continued in the fourth lecture; and the many admirable
experimental illustrations with which Dr. Tyndall has made us
familiar at the Royal Institution are freely introduced to develope
the subject more clearly.

The fifth lecture takes us into Dr. Tyndall's more special
domain of radiant heat, and the consideration of its relationship
to light. The subject of Fluorescence is fully discussed, and
the usual solution of sulphate of quinine, and the recently
discovered Thallene of Prof. Morton used to illustrate it. Then
we have an interesting paragraph relating to what is now called
‘Potential Light.” ‘‘ Fluor-spar,and some other substances, when
raised to a temperature still under redness, emit light. During
the ages which have elapsed since their formation, this capacity
of shaking the ether into visual tremors appears to have been
enjoyed by these substances. Light has been potential within
them all this time; and, as well explained by Draper, the heat,
though not itself of visual intensity, can unlock the molecules so
as to enable them to exert the power of vibration which they
possess.” The observations of Dr. Bence Jones appear to have
proved the existence of a fluorescent substance in the human
body, notably in the lens of the eye. Thus, if the eye be
plunged into the ultra-violet rays, it becomes conscious of a
‘‘whitish-blue shimmer” filling the space before it; and, ac-
cording to Dr. Tyndall, the crystalline lens of the eye, if it be
then viewed from without, is seen to gleam vividly. An account
of calorescence, and of the effects of the non-luminous ultra-
red rays is next given, and, near the end of the lecture, of the
refraction, polarisation, and magnetisation of heat. We cannot
completely understand the connection between the ultra-red rays
and certain phenomena in Nature (described on pp. 176 and 177,
and could almost imagine that a page or paragraph had been
omitted. We can find nothing in the text to prove that the
invisible ultra-red rays produce the warming and consequent
evaporation of the tropical oceans, and hence, indirectly, our
rains and snows. Again, a large flask containing a freezing
mixture, and coated with hoar-frost, was placed at an intensely
luminous focus of electric light, an alum-cell being interposed ;
the frost was not melted: when, however, an iodine-cell, which
cut off all the light, was interposed, and the alum-cell withdrawn,
the hoar-frost was melted. ‘Hence,’ says our author, ‘‘ we
infer that the snow and ice which feed the Rhone, the Rhine, and
other rivers which have glaciers for their sources, are released
from their imprisonment upon the mountains by the invisible
ultra-red rays of the sun.” Why hence? The experiment

1874.] Notices of Books. IOI

indeed proves, that if you cut off all the heat rays, the luminous
rays possess no warmth; while, if you cut off all the luminous
rays, the heat rays exercise great power; but it does not prove
to us that luminous heat plays no part in the phenomena of
Nature. A word or two of amplification, which considerably
simplify this part of the lecture.

The sixth and final lecture is devoted to the important and
rapidly growing subject of Spectrum Analysis, to which we need
not very specially refer. This lecture is terminated by no less
than nineteen pages of summary and conclusion. From this we
may with advantage note here and there, of necessity somewhat
desultorily, a remark or a generalisation. Dr. Tyndall speaks of
Newton’s emission theory in the following terms: ‘ For a
century it stood like a dam across the course of discovery ; but,
like all barriers that rest upon authority and not upon truth, the
pressure from behind increased, and swept the barrier away.”
Of the undulatory theory, he says, ‘It had been enunciated by
Hooke, it had been applied by Huyghens, it had been defended
By euler. But they made no impression. ... . . It first
took the form of a demonstrated verity in the hands of Thomas
Young. . . . After him came Fresnel, whose transcendent
mathematical abilities enabled him to give the theory a generality
unattained by Young. He grasped the theory in its entirety ;
followed the ether into the hearts of crystals of the most com-
plicated structure, and into bodies subjected to strain and
pressure. He showed that the facts discovered by Malus,
Arago, Brewster, and Biot, were so many ganglia, so to speak,
of his theoretic organism, deriving from it sustenance and
explanation.”

In his concluding remarks, Dr. Tyndall has addressed to the
Americans some admirable remarks concerning the so-called
practical scientific man and the original investigator. He has
begged them not to confound the two, not, as is too often the
case, to attribute the discoveries of the original worker to the
man who applies them to the practical good of mankind. And
he has besought them to endeavour to foster and cultivate
original research. ‘‘ Your most difficult problem will be not to
build institutions, but to discover men. You may erect labora-
tories and endow them, you may furnish them with all the
appliances needed for enquiry; in so doing you are but creating
opportunity for the exercise of powers which come from sources
entirely beyond yourreach. You cannot create genius by bidding
forit. . . . . . You have scientific genius amongst you—
not sown broadcast, believe me, it is sown thus nowhere—but
still scattered here and there. Take all unnecessary impediments
out of its way. Keep your sympathetic eye upon the originator
of knowledge. Give him the freedom necessary for his researches,
not overloading him either with the duties of tuition or of
administration, not demanding from him so-called practical

102 Notices of Books. (January,

results—above all things avoiding that question which ignorance
so often addresses to genius, ‘ What is the use of your work ?”
Let him make truth his object, however unpractical for the
time being, that truth may appear. If you cast your bread thus
upon the waters, then be assured it will return to you, though
it may be after many days.”

We trust our American cousins, or, as we should prefer to call
them ‘brothers, speaking the same dear mother tongue,” will
lay all this to heart, and let it bear good fruit. We rejoice to
know that one of our own scientific men has been received by
the Americans, as Dr. Tyndall has been received, and we trust
that the establishment of these social relationships will do
much to bind together the two great countries into still closer
union.

The Spectroscope and its Applications. By J. Norman Lockyer,
F.R.S. Macmillan and Co. London: 1873. 8vo., 117 pp.
Illustrated.

Tuis is the first volume of a series of popular works on Science,

to be called the Nature Series, because the subject-matter is first

printed in ‘‘ Nature.’ Eight of these books are already announced,
and some two or three will no doubt be ready by next October.

The design is good, and the books will probably supply a want

which is being felt in this country and America. Judging from

the present volume, the series will resemble Messrs. Hachette’s

Librarie des Merveilles more closely than any other works in our

language. The general appearance, as to externals, is altogether

prepossessing—the book is well printed on thick paper, profusely
illustrated, and very neatly bound.

The present volume consists of three lectures on the Spectro-
scope, delivered before the Society of Arts in 1869. They here
appear in a revived and somewhat expanded form, and the subject
has, as far as possible, been brought up to the day of issue.

The first lecture regards the matter from an historical and
descriptive point of view. The broad points of interest con-
nected with the history of the spectroscope are clearly discussed.
The proof that lights which differ in colour differ in refrangi-
bility; that the light of the sun consists of rays possesssing
different refrangibilities ; the decomposition and recomposition
of light. Newton, in his experiments, had used a round hole in
a shutter for the admission of a beam of light ; while Wollaston,
in 1802, made what our author calls ‘‘a tremendous step in
advance,” by substituting a slit instead of a circular hole. This
simple modification of Newton’s experiment permitted a spectrum
of considerable purity to be obtained for the colours, instead of
overlapping, were now seen more distinctly side by side, and
with only their edges overlapping. In this spectrum Wollaston
found breaks of continuity, not observed by Newton; he dis-
covered the black lines at right angles to the length of the

1874.] Notices of Books. 103

spectrum, which we now call “ Fraiinhofer’s lines.” Ten years
later, in 1812, the German optician, Fraiinhofer mapped no less
than 576 of these lines, and lettered the principal ones A, B, C,
D; he discovered, moreover, that in the spectrum of certain
stars, the black lines do not hold by any means the same position
which they hold in the spectrum of the sun. In 1830, the next
great improvement in the spectroscope was made. In addition
to the simple prism and slit, Mr. Simms, the optician, placed a
lens in front of the prism and another lens near the eye, so as
to magnify the spectrum. By this means the black lines could
be studied with far greater readiness than by the naked eye.
“You may imagine the enormous mystery—the wonderful
reverence almost—with which this question of the Fraiinhofer’s
lines was approached until they were thoroughly understood ;
and recollect that we owe the discovery of them, by which we
are enabled now to determine the pressures acting in the atmo-
spheres of the most distant stars, simply to the fact that Dr.
Wollaston, instead of drilling a round hole, used a slit; and to
the other additional fact, that Mr. Simms, instead of using that
slit with a mere prism, used a lens, and made the beam parallel,
and then aliowed that parallel beam, after it had passed through
the prism, to pass into another telescope, and form an image of
the slit for each ray. You see how closely connected are the
grandest discoveries with the skill and suggestiveness of those
who supply different instruments for our use.” Thus the principal
incidents in the history of the spectroscope, as an instrument,
are (a) Newton’s application of the prism to optical purposes, in
1675; (8) his observation that the prism should be used at the
angle of minimum deviation; (y) the addition of the slit by
Wollaston in 1812; (6) the collimating lens added by Simms in
1830. The author next describes various forms of spectroscopes
with one, two, or more prisms. Capital figures are given of
Steinheil’s four-prism spectroscope, used by Kirchhoff; of
Huggins’s star spectroscope, and of direct vision spectroscopes
with three or four prisms.

The second lecture treats of the applications of the spectro-
scope, specially of those which depend upon the investigation of
light radiated from bodies. Thus applied, the instrument enables
us to distinguish between solids, liquids, and gases; and between
gases and vapours existing at different pressures. The various
methods of obtaining spectra are here discussed; the use of the
Bunsen burner, the induction coil, and the voltaic arc. A coloured
plate at the commencement of the volume shows, among other
things, two spectra of great interest; the one of hydrogen at a
high pressure, the other of hydrogen at a low pressure. It is
here seen that, in the former instance, the spectrum is much
more continuous than in the latter. In fact, in the vacuous
tube, the hydrogen spectrum dwindles down to one or two very
sharply defined and thin lines. On the other hand, Frankland

104 Notices of Books. (January,

has proved that the spectrum of incandescent hydrogen existing
under very great pressure is entirely continuous. For inter-
mediate pressures we have intermediate spectra. ‘* We may
state generally,” says the author, “that beginning with any one
element in its most rarefied condition, and then following its
spectrum, as the molecules come nearer together, so as at last to
reach the solid form, we shall find that spectrum become more
and more complicated as this approach takes place, until at last
a vivid continuous spectrum is reached.” The latter part of
this lecture treats of the application of the spectroscope to the
investigation of the nature of various heavenly bodies, the sun,
stars, and nebule, at the hands of various physicists and astro-
nomers. The third and concluding lecture mainly discusses
absorption-spectra. It is here shown that it easy to detect
different substances by noticing their absorption ; by introducing
the substance between the source of light and the prism, and
noticing the resulting spectrum, side by side with a continuous
spectrum. We may discriminate between two solutions, the
one of blood, the other of magenta dye, exactly similar in
colour and general appearance. Again, Mr. Sorby has proved
that, by means of the spectrum-microscope, a blood spot so
small that it contains only one-thousandth of a grain of blood
may be detected. Some very interesting and comparatively new
matter is given near the end of this lecture relating to the
probably constitution of sun spots, the spectroscopic examination
of which seems to prove that they are due to ‘ general absorp-
tion, plus special absorption in some particular lines.” The
observed widening of the sodium line in the spectrum of a sun
spot is traced to difference of pressure :—‘‘ If we take a tube
containing some metallic sodium sealed up in hydrogen, and
pass a beam of light from the electric lamp through it, by
decomposing this beam with our prisms we shall obtain an
ordinary continuous spectrum without either bright or dark
lines; but by heating the metallic sodium in the tube, which is
placed in front of the slit, we really fill that tube with the vapour
of sodium; and as the heating will be slow, the sodium vapour
will rise very gently from the metal at the bottom, so that we
shall get layers of different densities of sodium vapour filling
the tube. Immediately the sodium begins to rise in vapour, a
black absorption-line shows itself, in one spectrum, in precisely
the same position as the yellow line of sodium, and you will find
that the thickness of the sodium absorption line will vary with
the density of the stratum of vapour through which it passes.
Thus, from the upper part of the tube we obtain a fine delicate
line, which gradually thickens as we approach the bottom of the
tube, and thus we produce the appearance in the spectrum of the
spot where the layers of sodium vapour are very dense, and the
very fine delicate line of the sodium vapour when thrown up into
the sun’s chromosphere.’ Thus, in fact, it seems to be undoubted

1874.] Notices of Books. 105

that, just as the hydrogen line widens as the surface of the sun
is approached, indicating increase of pressure, so, in the sun-
spot, the pressure of the incandescent sodium vapour increases
as we go deeper into the sun-spot cavity. Finally we have an
account of the velocity of solar storms, calculated from the
shifting of the F line, to be something like a hundred miles in a
second.

Altogether the work is very readable, and it will form a useful
introduction to larger works, such as that of Roscoe or Schellen.
It shows, however, frequent evidence of haste, both in style of
composition and in arrangement of subject-matter, and several
somewhat abstruse subjects receive rather slight treatment. We
regret also to notice the comparatively slight mention of foreign
investigators, and of our own Miller, Brewster, and Herschel.
But we must bear in mind that the subject is vast, and three
hours of exposition are very insufficient for a detailed account of
only one branch of it. We commend the work to all who
are interested in one of the most prominent branches of optical
science of our day, and remind them that it is the work of one
who has done good service to science by his own researches.

Light Science for Leisure Hours. Second Series. Familiar
Essays on Scientific Subjects, Natural Phenomena, &c.,
with a Sketch of the Life of Mary Somerville. By Ricuarp
A. Proctor, B.A., Cambridge, Honorary Secretary of the
Royal Astronomical Society, &c. London: Longmans,
Green, and Co. 1873.

Some years ago a caricature portrait of Alexandre Dumas was

published in Paris, in which the brilliant novelist was pictured

with a bunch of hands attached to each arm, and each hand
carrying a pen that was scribbling furiously. The flood of
books, magazine articles, controversial and other correspondence,
besides communications and hard secretary’s work to the Royal

Astronomical Society, which, during the last few years, have

poured from the pen of Mr. Proctor, render a similar caricature

almost justifiable, but it demands some modification. Instead of
merely a bunch of supplementary hands, the artist would, in this
case, require to depict an efflorescence of supplementary brains,

Mr. Proétor’s work having been something considerably beyond

the efforts of a mere book-maker. He has specially attacked the

grandest and heaviest of the sciences, and made it the leading
subject of his popular teaching; but, instead of re-baking the old
dishes of his predecessors, he has laid before his readers the most
recently discovered facts, generalisations, and speculations of
modern astronomy; a large proportion of which, according to
the old method of dishing up astronomical handbooks, would
have remained during another generation or so buried in the
Transactions of learned societies, or in the unread volumes
VOL. Iv. (N.S.) P

106 Notices of Books. (January,

of those who might be so simple-minded as to publish, on their
own account, important contributions to astronomical science,
under the delusion that they would be studied during their own
lifetime.

Mr. Proctor has the high merit—very rare among avowedly
popular teachers—of digging, with his own hands, into these
depths of astronomical literature, and of directly presenting to
readers of all classes judiciously selected and well displayed
examples of their treasures.

The second series of ‘‘ Light Science for Leisure Hours” is
one of the latest of these collections of nuggets (that is up to
this moment of writing; we cannot tell what may happen during
the short time that will elapse before this is published), and is
fully equal in interest and value to its predecessors.

A considerable portion of the volume is devoted to meteoro-
logical problems, and the interminable ‘‘ Gulf Stream” discussion,
into the lists of which tournament Mr. Proctor has valiantly
entered, the device on his shield being surface evaporation over
large tropical areas. He repeats Maury’s demonstration of the
insufficiency of Herschel’s trade wind explanation, and Herschel’s
refutation of Maury’s and Humboldt’s variation of the specific
gravity theory, and then proceeds to show that Dr. Carpenter’s
lump of ice, at one end of a rectangular aquarium trough, is a
fallacious representation of the arctic ice in arctic waters,
inasmuch as the ar¢tic area is so much smaller than the tropical
that the trough should have been v-shaped, with the ice at the
angle, in order to be at all representative. There can be no doubt
that this simple quantitative difficulty is fatal to Dr. Car-
penter’s large estimate of the potency of the arctic ice-cold
stream.

Taking a cool outside view of this controversy, it presents one
very interesting feature, namely that each combatant succeeds in
refuting the sufficiency of his opponents explanation, but (as far
as those above-named are concerned) all have failed to refute its
actuality. Hence we may venture to conclude that the errors on
all sides are quantitative only, and that the actual oceanic
circulation is due to the combined, or rather co-operating action,
of all the forces on behalf of which the champions are
respectively combating. We say no more, lest the infection of
the fight should come upon us and deform our critical impar-
tiality.

The other essays are on “ The Coming Transit of Venus ” of
course, ‘‘ The Ever Widening World of Stars;’’ Movements in
the Star Depths,” ‘*The Great Nebula in Orion,” ‘*The Sun’s
True Atmosphere,” ‘‘ Something Wrong with the Sun,” ‘* News
from Herschel's Planet,’ ‘‘ The Two Comets of 1868,” ‘* Comets
of Short Period,” ‘‘The Climate of Great Britain,’ ‘‘ The Low
Barometer of the Antarctic Temperate Zone.”

We cannot of course describe or discuss the contents of such

a tga bal

1874.] Notices of Books. 107

aseries. They are all written with Mr. Proctor’s usual graphic
clearness, and carry the reader forward with the latest steps
in the progress of those departments of science which they
treat.

Besides these, there is a critical sketch of the life and
works of Mrs. Somerville.

In his preface Mr. Proctor invites special attention to the essay
on the Transit of Venus, and expresses his practical conclusion
on this subject in unmistakable and uncompromising terms, in
italics, thus, that ‘“‘there is great risk that, for want of an
adequate number of southern stations, the whole series of
observations, by all countries engaged in the work, will result in
failure,” and he adds in a note that, ‘since this was written, I
have received letters from the greatest master of mathematical
astronomy this country has produced since Newton’s day,
strongly confirming my views as to the extreme importance of
providing many southern stations for applying Halley’s method
in 1874, and urging me, moreover, to appeal to America to take
part in this special work, for which she is peculiarly fitted,
because of the bravery and enterprise of her seamen, the skill
and ingenuity of her astronomers and physicists, and her
singular liberality as a nation in all scientific matters.”

Electricity and Magnetism. By FLEEMING JENKIN, F.R.SS.
L. & E., M.I.C.E., Professor of Engineering in the Uni-
versity of Edinburgh. (Text-Books of Science.) London:
Longmans, Green, and Co. 1873.

Or the great and increasing value of the series of text-books
published by Messrs. Longmans, there cannot be the remotest
doubt. Not only are the contents of each little work valuable to
the student, but it becomes a pleasure to the proficient to see the
principles of his science advanced so clearly and cleverly by the
best expounders. Professor Fleeming Jenkin has done ably by
electrical science in the above volume of the series; and par-
ticularly does he make clear the difficult subject of contact
electricity. We commend the work to the notice of our readers
interested in electrical science.

Quantitative Chemical Analysis. By T. E. THorpe, Ph., D.,
F.R.S.E. Professer of Chemistry, Andersonian Institution,
Glasgow. London: Longmans, Green, and Co.

Tuis work forms another of the “series of text-books of science,

adapted for the use of artisans and students in public and other

schools.” Its speciality is that the ‘examples chosen” have

108 Notices of Books. (January,

been selected to a great extent ‘‘on account of their practical
utility.” In other words, the work has a technological character,
which, without unfitting it for students of other classes, makes
it particularly suited for artisans. It is divided into five sections.
The first of these is a full and carefully compiled treatise on
chemical manipulation, as far as qualitative analysis is concerned.
The instructions on the use of the balance are admirable, and it
would not be easy to point out any necessary precaution which
the author has omitted to press on the attention of his readers.
Indeed it might be suggested that mention of the method of
weighing by vibrations, with the accompanying mathematical
formule, are not somewhat out of place in such a work. ‘There
is also an attempt at determining by algebraical calculations the
amount of wash-water, and the minimum number of washings
required to bring any precipitate to a state of purity. The use
of the filter-pump is explained at full length. The action of the
solvents employed upon the apparatus in digestions, evapora-
tions, &c., is pointed out as a possible, though generally
overlooked, source of error. In short, not merely students—in
the common sense of the term—but not a few chemists of old
standing might find their advantage in a careful perusal of this
section.

The remainder of the work consists of a graduated series of
examples in simple gravimetric analysis; of a section on
volumetric operations; of an account of the methods used in
the valuation of ores, minerals, and industrial products; and
lastly, of a special section on organic analysis.

Turning to the assay of pyrites, we find that the author directs
the sulphur to be oxidised by means of chlorate of potassa, and
not hydrochloric acid—as a certain standard work advises, with
the ordinary result of a small explosion—but nitric acid, which
works safely and well. The subsequent expulsion of the nitric
acid, the rendering all silica insoluble, the removal of the last
traces of sulphate of lead which may possibly be present, are all
duly pointed out as needful. The addition of a little tartaric acid
to prevent the precipitation of iron, along with the sulphate of
baryta, is a sound precaution. We have seen precipitates of
sulphate of baryta which, though thrown down from decidedly
acid solutions, had a very tawny look. The digestion with
acetate of ammonia to remove traces of nitrate of baryta which
may remain entangled in the precipitate is also useful.

Turning to the separation of phosphoric acid from iron and
alumina, we find that the author recommends the tin process
(Reynoso’s) to the exclusion both of the bismuth and of the
molybdenum method, the latter of which we certainly prefer,
whenever a comparatively small amount of phosphoric acid has
to be determined in prescence of a large proportion of iron and
alumina. The molybdenum process is, however, described and
recommended for the determination of phosphorus in irons and

ee eo

1874.] Notices of Books. 10g

iron ores. It is remarkable how generally chemists overlook the
fact that, when a substance has been ignited to remove organic
matter, its phosphoric acid will be to a great extent converted
into pyrophosphoric acid. Unless special precautions are taken
for its re-conversion, the amount of phosphoric acid found will be
decidedly erroneous.

The analysis of copper ores is very fully and clearly explained.
Now methods so accurate, convenient, and rapid as the ‘‘ Mans-
field”? and ‘‘ Luckow’s”’ are known, the question arises why the
Cornish dry assay, which gives tolerably correct results only in
the case of rich ores, should still be recognised ?

Space will not permit us to examine this work at greater
length. But although on certain points we should differ to some
extent from the author, we can conscientiously recommend the
work, not merely as a text-book for the student, but as
a useful manual of reference to advanced and experienced
chemists.

Workshop Appliances; including Descriptions of the Gauging
and Measuring Instruments, the Hand-Cutting Tools, Lathes,
Drilling, Planing, and other Machine Tools used by Engi-
neers. By C. P.*B. SuHELLey, C.E., Honorary Fellow of
and Professor of Manufacturing Art and Machinery in
King’s College, London. London: Longmans, Green, and
Co. 1973:

Turis also forms one of the series of Text-Books of Science, in
course of publication by Messrs. Longmans, Green, and Co.; the
subject embraced is, however, far too vast to be properly com-
prised within the pages of a single volume. As a text-book for
novices, it may be of some value; and that part which relates
to the use of hand tools will be found instructive, but it is the
only portion of it which possesses any originality. The first
chapter, ‘“‘On Measures of Length, and Methods of Measuring,”
is almost a reprint from another source, but it is interesting, and
forms a good introduction to the subjects subsequently treated
of. The description of ‘“‘ wire gauges” is defective, inasmuch
as no mention is made of Mr. Latimer Clark’s proposed gauge,
with which the author should be well acquainted. The latter
half of the book, which relates to machine tools, is of but little
use; the descriptive part is deficient, the mechanical details are
insufficiently explained, and many of the illustrations are from
old worn-out blocks which we recognise as having repeatedly
seen in manufacturers’ illustrated trade circulars. This portion
might well have formed the subject-matter for a separate volume,
and no doubt, if more space had been available for the purpose,
Mr. Shelley would have done it fuller justice than he has been
able to do within the limits to which he appears to have been
confined.

I10 Notices of Books. (January,

Sanitary Engineering : a Guide to the Construction of Works of
Sewerage and House Drainage; with Tables for Facilitating
the Calculations of the Engineer. By BaLtpwin LaTHam,
C.E., M. Inst. C.E. London: E. and F. N. Spon. 1873.

Mr. BALDWIN LaTHAM is a well-known authority on all matters
relating to Sanitary Engineering, and his experience in the con-
struction of town sewers and the disposal of sewage has been
such as to enable him to write from actual experience upon the
subjects treated of in the volume now before us. Much of the
information given in this book has appeared piecemeal elsewhere,
having formed the subject of papers read before the Society of
Engineers, and of pamphlets previously published by the author;
but these are so scattered as not to be always available—or,
indeed, convenient for reference—to anyone desirous of studying
the important question of Town Sanitation. In ‘ Sanitary
Engineering,” these previous writings by Mr. Latham have
been collated and published, with the addition of a considerable
amount of further information and experience, which together
form one of the most valuable publications we have met with
upon this important subject. In dwelling upon the importance
and necessity of sanitary measures, the whole community is
appealed to in a way easy to be understood by the non-scientific
world, whilst in dealing with the manner in which such measures
can best be carried out, Mr. Latham’s experience cannot fail to
prove of considerable value to future labourers in the same field
of engineering science. At various times and places, earth, air,
fire, and water have respectively been advocated as the best
means of disposing of fcoecal matter from towns, but, from
a comparison of London with other great centres of population,
where different methods have been applied, it is argued that
water-carriage ‘‘is the best adapted to the varied requirements
of a town population for effecting the speedy removal of the
principal matter liable to decomposition.”

In carrying into effect the works necessary for the sewerage of
a town, three distinct operations have to be performed, viz. :—
(1) The drainage of the surface; (2) The drainage of the
subsoil; and (3) The removal of foecal and other liquid refuse.
In these several operations, the mode of dealing with the rainfall
of districts comes under the first heading, and this is compre-
hensively dealt with, having due regard for varying situations,
the geological character and the physical outline of different
districts. On the subject of sewers—their form and relative
capacity—the information afforded is most complete, accom-
panied as it is by tables of discharge, &c. The course and
sectional form of sewers is well explained; but, perhaps, the
most valuable portion of the book for engineers is that which
relates to their construction under varying circumstances and in
passing through different geological formations, not the least
important part of the subject being that which relates to

1874.1 Notices of Books. III

the construction of sewers through sand and water-bearing
strata. The flushing and ventilation of sewers occupies a con-
siderable portion of the work, proportionate to its importance ;
whilst the concluding pages are devoted to the various forms of
water-closets, &c., having special reference to the best means of
connecting house-drainage with sewers. On the whole, this is a
work of considerable merit, and the author has dealt with his
subject in a clear and comprehensive manner, leaving little if
anything to be desired.

Annual Record of Science and Industry for 1872. Edited by
SPENCER F. Barrp. New York: Harper, Bros. London:
Sampson, Low, and Co.

THE second yearly volume of this work has just reached us. It

reminds the reader, in some respects, of the well-known * Year-

Book of Facts,” but it takes a wider range, and enters more into

detail. The ‘‘ General Summary of Scientific and Industrial

Progress during the Year,’ which is placed as an_intro-

duction, is carefully and fairly compiled, and gives a clear

view of the course of scientific discovery during the past twelve
months. The references to the various Transactions, journals,

&c., quoted, are made on a novel and, we think, useful system.

Each is designated by a letter and a number, the former

signifying the country where it is published, and the latter the indi-

vidual paper. An “Index to the References ” gives the explana-
tion. Thus, Ai signifies the ‘Chemical News.” ‘The number of

German scientific periodicals is significant, exceeding as it does

that of the English and French taken together. The authorities

quoted vary very much in value, and to some of the paragraphs
the editor has prefixed a judicious “‘it is said.” An extract
from a German journal recommends the addition of ammonia to
lessen the amount of sugar required in preserving acid fruits.

An excess of ammonia, we are told, can be remedied by the

introduction of a little vinegar. As the salts of ammonia.

especially the acetate, have a decidedly nauseous flavour, we
hope no lady will be persuaded to try this method.

Sanitary science is treated at great length. We notice para-
graphs calling attention to the danger of using soaps made from
putrescent animal matters, and extracts from Mr. Husson’s
paper on the milk of cows suffering from cattle-plague. A para-
graph on the comparative value of antiseptics, taken from the
‘“‘Academy,” assigns to benzoic acid a higher power than to
carbolic. ‘‘ Metallic salts,” such as sulphate of copper, occupy
the highest place, whilst ‘‘ inorganic salts,” with the exception
of bichromate of potash, ‘“‘have but little power.’ These two
statements seem scarcely reconcilable. General Scott’s process
for utilising, or, rather, for wasting sewage is described at length

112 Notices of Books. (January,

in an extract from the ‘English Mechanic.” We also meet
with the “recommendation” of the Rivers’ Pollution Com-
missioners. We trust that this is a ‘‘last appearance”’ prior
to its departure for that “limbo large and broad,” of which
Milton sings. There are many interesting paragraphs in this
book to which we may recur on a future opportunity. The work
further contains a list of eminent scientific men who have died
within the year, and concludes with an elaborate index.

The appearance of this volume is a proof of the increasing
demand for scientific literature on the other side of the Atlantic.
It is not improbable that in the course of a few years America
may occupy as prominent a position in chemical science and in
chemical manufactures as she has already done in the mecha-

nical arts.

Report on Béton Aggloméré; or Coignet-Béton, and the Materials
of which it is Made. By O. A. Gititmore, Major Corps
of Engineers, Brevet Major-General, U.S.A. Washington:
Government Printing Office. 1873.

Practical Treatise on Limes, Hydraulic Cements, and Mortars
By Q. A. Gittmore, A.M., Brigadier-General of U.S.
Volunteers. Fourth Edition, revised and Enlarged. New
York: D. Van Nostrand. 1873.

‘‘ Beton Aggloméré” is a term presumably unknown to the major

portion of mankind; ‘ Béton,” however, under its synonym of

‘‘concrete,” is to us dwellers in towns a well-known material.

Béton aggloméré is a concrete of superior quality, an artificial

stone, in fact, prepared under certain conditions from given

materials. The conditions are the use of the best materials;
the use of only sufficient water to convert the matrix of lime or
cement into a stiff, viscous paste; the incorporation of the solid
ingredients, as sand, with the matrix bya thorough or prolonged
mixing or trituration, producing an artificial stone paste, inco-
herent in character until compacted by pressure, by which every
grain of sand and gravel is completely coated with a thin film of
the paste; and, finally, this béton, or artificial stone, is formed
by thoroughly ramming the stone paste, in thin, successive
layers, with iron-shod rammers. The materials employed in
making this béton are sand, common fat, or hydraulic lime, or

Portland cement. Having given a concise statement of par-

ticulars and conditions favourable and unfavourable to the

formation and induration of this new artificial stone, General

Gillmore proceeds to consider, in a lengthy course of actual ex-

periment, its merit and demerit. This consideration is accom-

panied by a detailed description of the mortar-mixing mills, the
proportion of materials employed in, and the tensile strength
and other properties of the result of, the process. To complete
the means of comparison a series of experiments and abstracts

1874.] Notices of Books. II3

of experiments on Ransome’s siliceous concrete, the Frear stone,
the American building-block, the Sorel artificial stone, and Port-
land stone, are added. For the results, the reader—and even the
general reader will derive much useful information from the
work—be he builder, architect, or engineer, should refer to the
actual description of the experiments. A sample of the work,
however, may be epitomised from the chapter on artificial
Portland cement, and its production by the English wet and the
German dry processes. In the wet process we are told that the
works in the vicinity of London employ both white and grey
chalks of the neighbourhood, and clay procured from the shores
of the Medway and the Thames. ‘The clay and the chalk are
mixed together in the proportion of about one to three by weight,
and when a thorough mixture is effected in the wash-mill, the
liquid, resembling whitewash in appearance, is conducted to
large open reservoirs called bocks, where it is left to settle.
When the raw cement mixture has attained the consistency of
butter, it is shovelled out of the bocks, removed to stoves heated
by flues, and dried. When dry, it is burnt with gas-coke in per-
petual kilns. The cement-clinkers formed during the burning
are ground into the powder known commercially as cement. By
the dry process, the chalk, or marl and clay are kiln-dried, mixed
in suitable proportions, and reduced to powder. ‘This powder is
moulded into bricks from a stiff paste; the bricks are dried,
burnt, and ground, as in the wet process. ‘These processes,
described in four or five pages, including the proportions giving
best results, are supplemented by remarks which will be useful
to every practical engineer. General Gillmore’s work next
quoted in our list is equally full of information, but deals with
the class of hydraulic limes and cements only thus admitting
more general detail. Both works are likely to be of much prac-
tical utility to the builder or engineer.

Mind and Body: the Theories of their Relation. By ALEXANDER
Bain, LL.D., Professor of Logic in the University of
Aberdeen. Second Edition. Henry S. King and Co.
1873.

ProFessor Bain is well known as the author of a work on

Logic, and of various papers in the “Fortnightly Review,” one

of which, ‘‘On the Theories of the Soul,” is printed as the con-

cluding chapter of the volume before us. He is also known as

a prominent member of the Rationalistic school. We fear the

fact that this volume has reached a second edition in a very

short space of time is a sign that Rationalistic literature is
eagerly read in this country, and that the attitude of mind which
it develops is largely on the increase.
The subject which Professor Bain discusses in this volume is
the precise connection between the mind and the great nervous
VOL. IV. (N.S.) Q

114 Notices of Books. (January,

centre, the brain. He seeks to answer the question, ‘* What has
Mind to do with brain substance, white or grey? Can any facts
or laws regarding the spirit of man be gained through a scrutiny
of nerve fibres and nerve cells?” He reminds us, in the first
place, of the very intimate connection existing between mind
and body; the dependence of our frame of mind upon hunger,
fatigue, bodily illness, stimulants, &c. ‘‘ Bodily affliction,” he
remarks, ‘‘is often the cause of a total change in the moral
nature.” A little reflection will enable us to see that, although
the mind is influenced more or less directly by other organs, the
brain is the chief mental organ, and the mind is influenced
through it. The brain is a very large and complicated organ ;
it is computed to receive no less than one-fifth of the entire
amount of blood in the organism, which circulates through it,
and this surely indicates some considerable activity. Physiolo-
gists have proved that the brain is indispensable to thought,
feeling, and volition. Clever men usually have large brains, or
brains with numerous and deep convolutions. Thus, while the
average European brain weighs 49°5 ounces, that of Gauss
weighed 52°6, De Morgan 52°75, Dr. Abercrombie 63, and
Cuvier 64°5 ounces. We should like also to know the brain-
weights of Descartes, Humboldt, Mozart, and Sir Walter Scott.
Among idiots, brain-weights as low as 15, 13, and even 8’5 ounces
have been found. An ordinary man, Professor Bain remarks,
could not retain in his memory more than one-third or one-fourth,
perhaps even less, of the facts remembered by Cuvier. ‘‘ There
would be no exaggeration in saying that while size of brain
increases in arithmetical proportion, intellectual range increases
in geometrical proportton.”

An interesting account of the minute structure of the brain is
given in the third chapter, from which we learn that the grey
matter of the brain is composed of nerve-fibre mixed with small
pear-shaped corpuscles, with prolongations to connect them with
the nerves. The average diameter of the fibres is one six-thou-
sandth of an inch, while the corpuscles range from one three-
hundredth to one three-thousandth of an inch in diameter. The
number of nerve-fibres constituting the optic nerve is very large,
—probably there are as many as one hundred thousand. A few
useful woodcuts accompany these descriptions.

In the next chapter we find, among other things, a physical
theory of pleasure and pain, and in a long note (p. 75), we have
the author’s views regarding corporal and capital punishment.
In place of hanging, he advocates an electric shock, and in place
of flogging (which is revolting to the spectator, and inflicts per-
manent damage to the tissue), a succession of sufficiently severe
magneto-electric shocks. The fifth chapter treats of the intellect,
and at the outset destroys the long-existent idea that thought
may be conducted in a region of pure spirit, unassociated with
anything material. This is disproved by the fact that thought
exhausts the nervous system, just as bodily exercise exhausts

ts tanh lh 3 ep alin Nir Ee ee

1874.] Notices of Books. Er5

the muscles. Have we not even heard of people thinking them-
selves hungry? ‘The ‘ physical seat of ideas” is discussed in
this same chapter, where we also find a physical treatment of
memory, retention, or acquisition, which is defined as ‘the
power of continuing in the mind impressions that are no longer
stimulated by the original agent, and of recalling them at after-
times by purely mental forces.” Professor Bain explains
memory as an effect produced by the continuation in a weaker
form of the original impression which evoked the original nerve-
current. Just as when we hear the last clang of a bell an after-
impression of a feeble kind remains on the ear. But surely we
cannot imagine, in the case of memory, that the nerve-currents
are always flowing; if so, why is the effort of memory ever
necessary? If so, again, have we not motion produced from
nothing, or at least an original impulse producing indefinitely
continuous impulses, after the manner of perpetual motion ?

The book is full of sound logic; it is the work of an accurate
and active mind. It is a physico-metaphysical treatise, and to
the man of science sadly lacks the absoluteness of the experi-
mental fact. It is most pleasurable to read this book, yet we
confess that when we arrive at the last page we find ourselves
just as wise (or rather, ignorant) as we were before, in regard to
the nature of mind.

On the Origin and Metamorphoses of Insects. By Sir Joun
Lupsock, M.P., F.R.S. Illustrated. Macmillan and Co.
London; 1874. 108 pp., crown 8vo.

SIR JOHN LuBBOCK is well known to the world as an archeologist

and anthropologist, and perhaps less well as an entomologist.

Yet he has contributed no less than thirty-five papers to the

Royal Society, and to various magazines, on entomology during

the last twenty years; and, as he is not yet forty, we perceive

that he must have studied the subject at a very early age. His
first paper, ‘‘On Labidocera,” appeared in the ‘‘ Annals and

Magazine of Natural History” for 1853.

The little work before us embodies in a popular form many of
the more interesting results of his observations condensed from
the above-mentioned memoirs. The articles have already
appeared in ‘“ Nature,” and the work forms the second volume
of the Nature Series of books, which Messrs. Macmillan are now
publishing.

The main subjects discussed are the classification, origin, and
the nature of the different metamorphoses of insects; various
views are traced, from the old standard “‘ Entomology ” of Kirby
and Spence, one of the Bridgewater treatises, to the more recent
memoirs of Miiller, Agassiz, and Packard. ‘The intelligence of
insects comes out in a remarkable light. Many of our readers
will remember Sir John’s tame wasp at a recent meeting of the
British Association, He remarks ‘we are accustomed to class

116 Notices of Books. (January,

the anthropoid apes next to man in the scale of creation, but if
we were to judge animals by their works, the chimpanzee and the
gorilla must certainly give place to the bee and the ant.” For
example (p. 11), the larve of certain insects require animal food —
as soon as they are hatched, and the mother-inse¢ct consequently
provides them with caterpillar and beetles, by burying them in a
cell side by side with the unhatched larva. But here a difficulty
arises: ‘‘if the Cerceris were to kill the beetle before placing it in
the cell, it would decay, and the young larva, when hatched, would
only find a mass of corruption. On the other hand, if the beetle
were buried uninjured, in its struggles to escape it would be
almost certain to destroy the egg.’ Look then at the wonderful,
but diabolical, instinct of the creature. ‘‘The wasp has the
instinét of stinging its prey in the centre of the nervous system,
thus depriving it of motion, and let us hope of suffering, but not
of life; consequently, when the young larva leaves the egg, it
finds ready a sufficient store of wholesome food.” A certain
species of ants keeps Aphides in bondage, just as we do cows,
for the sake of the honey-dew which they collect ; a certain kind
of red ant is indolent, and keeps black ants to do work for it.
Once more, there is a kind of beetle which is blind and helpless
usually found in ant’s nests; the ants care for all their wants and
nurse them tenderly. These things, and much more, of the lives
of insects are told us in popular language in Sir John’s book,
which we recommend, not alone to the entomologist, but to the
general reader.

Ozone and Antozone: their History and Nature. By C.B. Fox,
M.D. London: J. and A. Churchill.

Ir, as Dr. Fox not unjustly remarks, ‘to the philosopher, the
physician, the meteorologist, and the chemist there is perhaps no
subject more attractive than that of ozone,” it must be conceded
that there are few subjects in experimental science more fraught
with difficulties and involved in doubts. Since Schonbein first
announced his discovery more than thirty years of research and
observation have elapsed, yet the very existence of ozone is little
more than generally conceded. As to the laws of its occurrence
and distribution, its properties and functions, the means for its
recognition, and its artificial production, there is a singular
amount of discrepancy in the results of different observers.

As to antozone, it is still regarded by many chemists—in
England at least—as little better than mythological. Such being
the case, there is evidently room and need for a work like the
present. Dr. Fox has undertaken the laborious task of giving a
digest of the most important facts connected with ozone and
antozone, comparing and, as far as practicable, harmonising, the
views of former investigators. He endeavours to ‘‘point out the
circumstances, and the manner in which, and the reason why,
ozone is observed in the atmosphere,” and finally gives the
results of his own observations,

1874.] Notices of Books. 117

The concluding section, on the methods of observing and
detecting ozone in the atmosphere in the air, is without doubt
the most interesting and valuable. The author concludes that
iodised litmus and simple iodide of potassium are the only tests
that can be considered trustworthy. For the precautions to be
observed in their employment we must refer to the book itself.
We are bound to declare that, in our conviction, Dr. Fox has
merited well at the hands of the scientific public for the elaborate
and well-arranged digest of facts which he has placed at their
disposal, and we join him in the hope that his labours will furnish
a sound basis for future investigations.

Elementary Treatise on Physics, Experimental and Applied, for
the Use of Colleges and Schools. ‘Translated and Edited
from Ganot’s ‘“‘ Eléments de Physique.” By E. ATKINson,
Ph:D:, F.C.S., Professor of Experimental Science, Staff
College, Sandhurst. Sixth Edition, revised and enlarged.
London: Longmans and Co. 1873.

THE most prominent enlargements to this edition consist in further
elucidation of the laws of the polarisation of light, a description
of Gramme’s continuous magneto-electric generator, and a
further development of the theory of heat as recently advanced.
We are glad also to notice an extension of fundamental formule.
Nothing need be said in further praise of so eminently a standard
work.

A Treatise of Medical Electricity, Theoretical and Practical ;
and its Use in the Treatment of Paralysis, Neuralgia, and
other Diseases. By Jurius’Artuaus, M.D., M.R.C.P:
Lond. Third Edition, enlarged and revised, with 147
illustrations. London: Longmans, Green, and Co. 1873.

In religious dogma everyone knows the old saying that described
orthodoxy as ‘my own peculiar doxy,” and heterodoxy as
“‘everybody else’s doxy.” But dogma (taken in its sense of
enforced opinion) is not peculiar to religious discussion ; the next
elder science, that of medicine, has been full of it from the days
of Asculapius and Galen till now. Even now we are not free
from the error of recording opinion instead of fact. And such
a view is impressed upon all students of electro-medical
science. The opinions held in contrast with the facts ascertained
and stated without bias, are in overwhelming proportion. Indeed,
the proportion is so great, that the influence of error is per-
ceptible upon the minds of the public, who are too apt, perhaps,
to regard electro-medical practitioners with not a little undue
severity. It is then the duty of a scientific serial to uphold the
careful chronicle of facts, and discourage the register of mere
opinion, founded, if of any foundation, upon incomplete observa-
tion of fact. Thus it is our duty to commend to those who may
be about to become interested in electro-medical science the

118 Notices of Books. (January,

perusal of Dr. Althaus’s book, and to express congratulation
upon the attaining of a third edition. But not only will the
reader in search of medical knowledge find here what he re-
quires, but the general electrician will find also complete record
of observations as to the action of electricity upon physiologically
organic substances.

A Treatise on Acoustics in Connection with Ventilation, and an
Account of the Modern and Ancient Methods of Heating
and Ventilation. By ALEXANDER SAELTZER, Architect.
New York: D. Van Nostrand.

Mr. SAELTZER has given his subject great attention, and this
attention has led him to some highly original views upon the
relation of the propagation of sound to the density of the air,
and the propagation of sound waves across strata of different
density. Given the air and the propagation of sound waves
across strata of different density, the author shows how it is
that the voice of a speaker, whether proceeding from pulpit,
platform, or proscenium, may be so reflected by the surface of
the different air-strata as to be inaudible or confused to the
hearers above or below the strata in which he speaks. Mr.
Saeltzer next recounts the experiments that have led him to
adopt certain principles of ventilation as aids in developing the
acoustical properties of public buildings, by breaking up the
air-strata. The book should be read, not only by the architect,
but by every professional man whose duty it is to speak in public.

Experimental Research on the Causes and Nature of Catarrhus
Estivus (Hay-Fever, or Hay-Asthma). By C. H. BLacktey,
M.R.C.S. Eng. London: Bailliére, Tindal, and Cox,
King William Street, Strand.

Mr. Blackley may be fairly congratulated on having produced
a work which is not merely a valuable contribution to our medical
literature, but which will be read with interest by many scientific
men not connected with the profession.

Long-Span Bridges. By B. Baker, Assoc. Inst. C.E. Revised
Edition. London: E. and F. N. Spon. 1873.

To the student or to the engineer who desires to investigate the
comparative theoretical and practical advantages of the various
adopted or projected types of bridge construction, whether in-
cluding box-plate, lattice, or bowstring girders, ribs, or sus-
pension, we cordially commend this little work, as readable as it
is accurate. The work really includes two sections, relating
respectively to long- and to short-span bridges, and is illustrated
with diagrams of type form built upon the long-span system.

1874.] ( 119 )

PROGEESS: IN. SC LENCE

MINING.

STATISTICS of considerable interest in connection with the coal-produce of
this country have been published during the past quarter. The official returns
furnished by the twelve Government Inspectors to the Home Office show that
in 1872 there were 3016 collieries at work in Great Britain. In the previous
year the number of mines was 3100. But in 1871 the number of coal-miners
employed reached 418,088, whilst in 1871 the colliers numbered only
370,881. It appears that during 1872 the amount of coal raised was
123,393,853 tons, compared with 117,439,251 tons during the preceding year.
This gives a decrease in the amount of coal raised per man; for whilst the
average quantity gotten by each miner in 1872 was 295 tons, it amounted to
316 tons per manin 1871. As to the accidents, we note an increase in their
number, but a slight decrease in the resulting deaths. Thus, in 1872 there
occurred 894 separate fatal accidents, resulting in the loss of 1060 lives; in
1871 there were only 826 similar casualties, but they represented a sacrifice of
1075 lives. As usual only a small proportion of the deaths could be traced to
explosions of fire-damp; indeed, out of the ro60 deaths in 1872 only 154 were
due to such explosions.

It is not long since we called attention to some investigations on the
connection between colliery explosions and the state of the weather, under-
taken by Mr. R. H. Scott, F.R.S., of the Meteorological Office, and Mr. W.
Galloway, who is now Assistant-Inspector of Mines in Scotland. These
observers have since extended their researches, and have recently published
an analysis of the catalogue of accidents which occurred during the year 1871.
On the whole there were 207 explosions of fire-damp, of which 52 were attended
with fatal consequences. It is believed that 113 of these explosions, or55 per cent
may be traced to the low state of the barometer: and that 39, or 1g per cent,
are referable to a rise of temperature; whilst the remainder are unexplained
by either of these meteorological causes. The paper contains some valuable
instructions respecting the method of recording barometric and thermometric
observations ; these, of course, deserve careful study by the miner, especially
now that the Coal Mines’ Regulation A& of 1872 requires that ‘after
dangerous gas has been found in any mine, a barometer and thermometer shall
be placed above ground in a conspicuous position near the entrance to the
mine.” With regard to atmospheric pressure, the authors remark that
if the barometer, after having remained nearly stationary for several days,
descend half an inch or an inch during the next two or three days, the miner
may expect to find fire-damp in greater quantity than usual in cavities in the
roof and in the higher parts of the workings, and it may also appear where it
had not been previously detected. If the temperature rise to 55° or upwards, the
ventilating current is likely to be retarded. A sudden fall of the barometer—
an inch in twenty-four hours or so—or a further fall after it has been unusually
low for a day or two, points to the possible escape of gas, and calls for in-
creased ventilating power, especially if the diminution of pressure be coupled
with a rise of temperature.

We may observe that Mr. Galloway obtained the first of the prizes offered
by Mr. Hermon, M.P., for Essays on the Prevention of Colliery Accidents.
This Essay, which has recently been published in the “‘ Mining Journal,” is
worthy of attentive study by those who have charge of our coal-mines.

Coal-cutting machinery received a fair share of attention in the Mechanical
Section of the British Association at the late Meeting. Mr. Firth, of Leeds,
well known for his zeal in promoting the use of such machines, read a paper
“On the Introdu@tion of Working Coal-Cutting Machinery in Mines.” In
this communication he described in detail his own form of coal-cutter, worked

120 Progress in Science. (January,

by compressed air ; and during the meeting he gave many of the members an
opportunity of seeing it at work in his pits at West Ardsley. Mr. Firth’s
machine has already been described in this Journal, and we have also noticed
his efforts to promote the introduction of coal-getting machinery by offering
some time ago a premium for the best form of machine.

At the same meeting, Dr. W. J. Clapp described the ‘“ Universal Coal-
Cutting Machine,” used at Nant-y-glo; this machine is driven by compressed
air, but has the action of a borer rather than that of a pick. Mr. J. Plant, of
Leicester, read a paper ‘‘On the Burleigh Rock Drill,” and two examples of
the drill were actively at work in the yard of the Church Institute, close to
the room occupied by the Mechanical Section.

A new form of safety-lamp has been described before the North of England
Institute of Mining Engineers, by Mr. Emerson Bainbridge, of Sheffield.
The light is protected by a cylinder of glass below and of brass above, so that
wire-gauge is scarely used in its construétion.

‘‘ The Application of Compressed Air to Underground Haulage” was the
title of a paper lately read before the Dudley Institute of Mining Engineers,
by Mr. A. J. Stevens, of Newport, Monmouthshire. After comparing the cost
of using steam-power underground with that of applying the steam to the
compression of air, he described a small and apparently simple winding-
engine, which he has recently patented, with the view of dispensing with
animal power for underground haulage.

Deposits of coal, almost unrivalled in magnitude, are described by Baron
Von Richtofen as existing in certain provinces in China. Whilst in the
maritime provinces the coal-measures have been in some places completely
removed by denudation, and in others only imperfe&ly preserved, some of the
inland provinces are singularly favoured, and exhibit fine exposures of their
coal-bearing rocks. The province of Shansi contains at least 30,000 square
miles of coal-producing ground, occupied partly by a fine bituminous coal and
partly by anthracite. Some of the coal-seams are said to attain a thickness
of 30 feet. In fact China offers to the miner coal-fields which are said to
rival, if not to surpass, even those of the United States.

A description of the iron-ores of the Bidasoa, in the Pyrenees, by Dr.
Rohrig and Mr. Haas, has appeared in a recent number of the ‘‘ Chemical
News.” The mineral seems to be chiefly spathose ore, or carbonate of iron,
superficially changed by atmospheric influences into a brown iron ore, or
hydrous peroxide. From the published analyses the ores appear to contain
more or less manganese; and, as no phosphorus is recorded, they would
probably produce a pig-iron remarkably well adapted for conversion into
Bessemer steel. The ores occur in highly-inclined lodes, coursing for the
most part through syenite, though some of the lodes are found in adjacent
Silurian rocks and others in Triassic limestones.

In the Island of Anglesey a valuable deposit of copper-ore has long been
worked at the Parys Mountain, but it is a disputed point whether this
represents the only great treasury of mineral wealth in that island, or whether
copper-lodes sufficiently rich to be worked are not widely distributed. It
consequently becomes a matter of interest to notice any local vestiges of old
copper workings in this island. The Hon. W. O. Stanley has communicated
to the Royal Archzological Institute some interesting notes on this subject.
It is hardly to be doubted that copper was exported from Anglesey prior to
the landing of the Romans, and, indeed, the mineral wealth of Mona may
have attracted the Romans thither. About the year 1640 a cake, or massa, of
smelted copper was discovered, bearing the inscription ‘‘ Socio Rome.” It is
said to have been found at Caerhén, the ancient Conovium. In 1840 a second
cake was discovered in Llangwyllog, and in 1869 three cakes were found at
Castellor. Two years later three cakes were dug up at Bryndon, Amlwch,
and passed into the hands of Mr. T. F. Evans, who has described them in a
recent number of “Iron.” One of the cakes is remarkable for being stamped,
on two hunches, with the letters IV L S. They are curious relics, which may

1874.] Metallurgy. 121

have been smelted for use in making the bronze weapons and implements
known to have been used at an early epoch of civilisation.

METALLURGY.

Some valuable researches on alloys, especially on those of copper and tin,
have been conducted at the Paris Mint by M. Alfred Riche, who has recently
published his results in the “ Annales de Chimie et de Physique.’? The
fusibility of the alloys was determined by means of Becquerel’s thermo-
ele&tric pyrometer, with platinum and palladium wires, constructed by
Ruhmkorff. The author finds that most alloys of copper and tin suffer
liquation at the moment of solidification, and hence it is almost impossible to
obtain their true melting-points. Exceptions, however, are furnished by those
alloys whose atomic constitution corresponds to the formule SnCu; and
SnCu,; these alloys are not liquated, and the former of them possesses
peculiar properties, differing in colour, for example, from all others of this
class. Tempering increases the density of bronzes rich in tin, and annealing
diminishes the density of tempered bronze. Whilst steel is hardened by being
suddenly cooled, bronze is softened by this treatment. Yet the bronze is not
sufficiently soft to be readily worked; and it has long been a vexed question
how the Chinese manage to work their tam-tams and other instruments of
bronze. Experiments made many years ago at the Ecole des Arts et Métiers,
at Chalons, showed that such objects might, though with much trouble, be
wrought in cold-tempered bronze; but the process was too difficult to be
employed industrially. It was afterwards asserted by St. Julien that the
Chinese worked their bronze at a red heat; yet it was difficult to understand
this, since bronze is extremely brittle at high temperatures. M. Riche appears
to have settled the difficulty by showing that although bronze cannot be
readily worked either cold or at a bright red heat, yet it is easily manipulated
at intermediate temperatures. Taking advantage of this fact, M. Riche and
M. Champion have succeeded in imitating the Chinese tam-tams.

With respec to unalloyed copper, Riche finds that its density when alter-
nately submitted to mechanical treatment, tempering and annealing, is
variously affected according as the metal is protected from or exposed to access
of air; in the former case the mechanical action increases, and in the latter
case diminishes the density. The introduction of a small proportion of iron
gives considerable tenacity and hardness to copper. The author has also
studied a number of alloys of copper and zinc.

Within the last year or two considerable attention has been dire@ed to the
so-called ‘* Phosphor-Bronze,” an alloy of copper and tin, with more or less
phosphorus, according to the purposes for which it is intended. Messrs.
Montefiore-Levi and Kiinzel have brought this alloy to great perfection, and
have applied it to a great variety of industrial uses, whilst in this country it
has been prominently brought forward by the Phosphor-Bronze Company.
When the proportion of phosphorus is large the alloy is extremely fluid, and
therefore well adapted for castings; whilst its fine colour and close texture
recommend it for decorative work. Certain forms of the bronze are charac-
terised by great ductility and malleability; and may be readily rolled, drawn,
or embossed; whilst other varieties are as hard as soft steel, and may be
worked into tools and cutting instruments for use in gunpowder mills. It has
been much recommended for ordnance and small arms; whilst the miner has
used it for the wire ropes of his winding machinery, and the iron-smelter for
the tuyeres of his blast-furnace. Numerous experiments on the mechanical
properties of phosphor-bronze have been made at Berlin and Vienna, and by
Mr. Kirkaldy in this country.

A detailed account of some experiments on Swedish steel, conducted by
Mr. Kirkaldy, at his Testing Works at Southwark, has lately been published.
The specimens tested were manufactured at the Fagersta Works by Mr.
Christian Aspelin, and have been exhibited at Vienna. The enquiry was
directed to the behaviour of the steel under the action of tensile, compressive,

122 Progress in Scrence. [Januaty,

transverse, twisting, and shearing stresses; in fact, to all such strains as
actually occur in engineering works.

A new mode of tempering steel has been suggested by M. Caron. His plan
is to plunge the red-hot metal into water heated to about 55° C., and he also
proposes to restore ‘‘ burnt iron” by a similar process.

The nature and uses of modern steel formed the text of Mr. Barlow’s
address as President of the Mechanical Section at Bradford; and although it
naturally dealt chiefly with mechanical questions, it is yet deserving of the
metallurgist’s attention. To the same section Mr. Joseph Wilcock con-
tributed a paper on the Bowling Iron Works at Bradford, in which he traced
the history of iron-making in this distri@, and gave an excellent description
of these extensive works. The Bowling and the Low Moor Iron Works,
both celebrated for the manufacture of boiler-plates, were visited by many of
the members of the British Association.

Sir Francis C. Knowles has recently laid before the Society of Arts a de-
scription of his method of refining and converting cast-iron into either
malleable iron or steel. His obje& is to effet the conversion without the
waste of heat and material which attends puddling and other converting pro-
cesses now in use. Sir Francis employs as his source of heat the combustion
of gases rich in carbonic oxide, and mixed in due proportion with atmospheric
air heated to 500°C. Having melted the pig-iron in a cupola with coke or
anthracite, he collects the gases, frees them if necessary from carbonic
anhydride, enriches them by addition of free carbonic oxide, and is thus
enabled to produce by their combustion a temperature of 2500°C. If higher
heat and greater rapidity be required, he uses the cupola-gases for heating
his retorts, and employs pure carbonic oxide specially generated, and thus
obtains a temperature of 2979° C. In either case the mixture of carbonic
oxide and air is blown into the molten metal, thus producing carbonic
anhydride and nitrogen at a high temperature ; but this heat may be readily
utilised, whilst the products of combustion are passed through kilns or retorts,
containing anthracite or coke, and the carbonic anhydride is thus reduced to
carbonic oxide, which is again available for combustion. The finery or con-
verter used in this process is peculiarly constructed, with the view of with-
standing the high temperature to which it is subjected, and the interior is
lined with a mixture of protoxide of iron, manganese, emery, bauxite, and
caustic soda; a highly basic preparation is thus obtained for the lining, as it
is considered desirable that the cinder should also be basic, not containing more
than 30 percent of silica. To eliminate the sulphur and phosphorus, caustic
soda and rich oxide of iron or manganese are employed; and when superior
iron and steel are to be prepared the use of nitrate of soda or permanganate
of soda is recommended. It will thus be seen that, so far as the oxidising
agents are concerned, the process is only a modification of the Heaton process.

MINERALOGY.

Two distiné& minerals are known in jewellery as Cat’s-Eye; the one being
an opalescent quartz enclosing asbestiform fibres, which, lying in parallel
directions, give the appearance of a fibrous structure to the quartz; whilst
the other mineral, sometimes called for distin&tion sake, “oriental cat’s-eye,”
is a fibrous chrysoberyl. Some very fine cat’s-eyes have been received within
the last year or two from the Cape of Good Hope. These stones are
generally of a rich brown colour, but occasionally blue, red, and white. Some
authorities have regarded the Cape cat’s-eye as a form of crocidolite, whilst
others have supposed that it is only a coloured fibrous quartz; but its true
character appears to have been determined by Dr. Wibel, of Hamburg. After an
attentive study of the chemical and microscopical properties of the mineral
in question, he comes to the conclusion that it is not strictly fibrous quartz,
but a pseudomorph of quartz after fibrous crocidolite. He shows that the
so-called brown fibrous quartz, originally described by Klaproth, is merely a
mixture of pure white quartz with goethite, or hydrous peroxide of iron;

1874.] Engineering. 123

whilst the blue variety is essentially a mixture of white quartz and crocidolite.
The fibrous character is, in both cases, due to the replacement of fibrous
crocidolite by quartz; the brown variety being the product of a perfe& and
slow alteration, whilst the blue is the result of an imperfect and rapid alteration.

Among the ejections from the eruption of Vesuvius in 1872, there occurred
certain minute crystals, which were described by Scacchi as a new species
under the name of Microsommite. This species has recently received attentive
study by Vom Rath, who, in spite of the unusually small size of the crystals,
has had the patience and acuteness to examine them crystallographically.
About 1500 of these little crystals, weighing together only ~,th of a gramme,
have passed through his hands. The crystals are colourless hexagonal prisms,
striated vertically, and terminated by dull basal planes. The hardness is
about equal to that of felspar; and the specific gravity is 26. An analysis of
the very small quantity at Vom Rath’s disposal yielded:—Silica, 33;
alumina, 29; lime, 11'2; potash, 11°53 soda, 87; chlorine, 9°1; sulphuric
acid, 1°7.. The following expression is given as the probable formula :—

(2K,0,3CaO),A1,03,2Si02-+ NaCl+ 4,Ca0.SO3.
The origin of microsommite may be traced to, the reaction of steam, charged
with chloride of sodium, on the volcanic minerals leucite and augite.

Under the name of Horbachite a new ore of nickel has been described by
Dr. Knop, of Carlsruhe. In the neighbourhood of Horbach, near St. Blasien,
in the Black Forest, there occurs a deposit of this ore, which has at different
times invited exploration. The ore has been described as anickeliferous magnetic
pyrites, but analyses of the pure mineral show that it is really a distin@ species.
The mean of several analyses gives:—Sulphur, 45°87; iron, 41°96; nickel,
1r‘98. From this result we may deduce the formula 4Fe2S3+Ni2S3. Knop
calls attention to this association of sulphides as unique, no metallic sesqui-
sulphides having previously been known to occur in a native state.

Some recent observations by Dr. Schrauf, of Vienna, show that Brookite,
one of the three native forms of oxide of titanium, must be referred to the
oblique or monoclinic system. The crystals affect, however, a decidedly
prismatic habit ; hence the reason why previous observers have placed this
species in the prismatic system. Schrauf recognises three distinct types of
crystal in brookite.

Prof. Rammelsberg has laid before the German Geological Society some
papers on mineral arsenides and sulphides. In one of these he discusses the
mutual relations and the chemical constitution of the compounds of arsenic
and antimony which occur native. He is led to regard the metallic arsenides
not as true chemical compounds, like the sulphides, but as isomorphous
mixtures of metal and arsenic; whilst the sulpharsenides are mixtures of
these with bisulphides. What he says with respect to the compounds of
arsenic applies also to those of antimony.

Some beautiful crystals of Torbernite, or uranium-mica, have been recently
raised in Cornwall, we believe from the neighbourhood of Redruth. They
are notable for exhibiting an unusual development of the pyramid, so that
the crystals are very different in general appearance from the common tabular
forms.

A preliminary description of the meteoric stone which fell, some years ago,
at the Barratta Station, near Deniliquin, in Australia, has recently been
published by Mr. Archibald Liversidge, of the University of Sydney.

Nefediewite is a new Russian mineral, described by Pusirewsky. It seems
to be an amorphous substance, resembling lithomarge.

ENGINEERING—CIVIL AND MECHANICAL.

Harbour Works.—On the 25th November last, Mr. L. F. Vernon Harcourt
read a paper before the Institution of Civil Engineers on the construction and
maintenance of Braye Bay Harbour, Alderney. This harbour was designed
by the late Mr. James Walker, C.E., and the works in connection with its
construction were commenced in 1847. The Admiralty intended, in the first

124 Progress in Science. [January,

instance, to make only a small harbour, but subsequently gave directions for
the enlargement of the scheme. In 1856, the design, then in course of con-
struction, consisted of a harbour of 150 acres, with a depth of water of
3 fathoms and upwards, sheltered to the west and east by two breakwaters.
The western breakwater, about 4700 feet in length, had been constructed, but
the eastern breakwater was abandoned; and the harbour was consequently
exposed to winds blowing from any quarter between N.N.E. and E.S.E. The
western breakwater was exposed to the whole force of the Atlantic, and the
effect of the fury of the storms was increased at Alderney by the rapidity of
the tides near the island, occasioned by a peculiar confluence of currents in
the bay of St. Malo. The breakwater was constructed on the “‘ pierres
perdues”? system—a mound of rubble-stone being deposited in the line of
the proposed work from hopper barges towed out by steam-tugs. As soon as
the mound was sufficiently consolidated, it was surmounted by the super-
structure, consisting of a sea wall and of a harbour wall 14 feet and 12 feet
thick respectively, flooded at first at the level of low water, and built without
mortar, the intermediate spaces being filled up with rubble, the batter of the
sea wall being g inches and of the harbour wall 4 inches to1foot. To protec
the lower or quay level, a promenade wall, 14 feet high, was built on the sea-
side, consisting of two masonry walls set in mortar, with filling between. In
1860, when the superstructure had been carried out 2700 feet from the shore,
the design was somewhat modified. The breakwater was narrowed by
reducing the width of the quay to 20 feet, the batter on the sea face was
altered to 4 inches in a foot, solid masonry was substituted for the concreted
hearting, and the foundations of the harbour wall were commenced at the
same level as the sea wall. The head was built in 1864. The foundations
were laid 24 feet below low water level, across the whole width of the break-
water. The first nine courses, each 3 feet thick, consisted of concrete blocks
faced with granite headers; the upper portion was built of masonry in cement.
The most exposed face stones were joggled and dowelled together, and several
of the corner quoins were further secured by iron bars and diagonal straps.
Two red leading lights on the shore mark the entrance to the harbour at night.
The cost of the works of construction and maintenance to 1872 amounted to
£1,274,200, of which £57,200 was expended in repairs.

Water Supply.—With a view to improving the water supply of Paris, the
Montsouris Reservoir is now in course of construction to receive the waters of
the Vanne. It occupies an area of 54,000 square metres, or 13} English acres,
and will contain 300,000 cubic metres, or 66,000,000 gallons of water, being
the amount of three days of the normal flow of the canal which supplies it.
The entire work is constructed of stone and cement, the exterior walls being
strengthened by oblique arches having a thickness of 3 metres. The bottom
is level except at the approaches to the wall, where is a series of sumpts of
little depth, separated by partitions in order to form a number of arches which
support the interior gallery. In front of each of the recesses thus formed are
pillars, carried up to support the vaults of the arches which form the top of
the building. The river Vanne is expected to afford daily a supply of about
100,000 cubic metres, or 22,000,000 gallons of excellent water. Hitherto the
daily supply of water to Paris per head, as a mean, has been but 24 gallons;
with the addition of the Vanne water, this will be raised to about 34 gallons.

Sewage.—The great development of the industries of the town of Rheims,
and its consequent increase of population, having led to the necessity of pro-
viding facilities for the disposal of the sewage, a commission was appointed to
investigate the subject, and it was decided, in 1870, to establish on a large
scale a system of chemical purification, and a dire@ application of the sewage
to agricultural purposes. Two processes have been tried—purification direc
by chemical means, and irrigation. The Suvern agent, composed of chloride
of magnesia, of lime, and of tar, was tried without effect, and the application
of sulphate of alumina was equally unsuccessful. The latter process did,
however, produce a certain effe@, but an imperfect one, and that at an enormous
cost. The most successful trial was that made with a mixture proposed by

1874.] Engineering. 125

MM. Houzeau and Devédeix, composed of a combination of lime and
aluminous lignites, which latter are found in abundance in the vicinity of
Rheims. MM. Houzeau and Devédeix’s process was subjected to an extensive
trial, and 2,500,000 cubic feet were thus treated in 1872. The cost for the
purifying mixture per cubic foot was very trifling, and from the experience
gained from the experiments, it was found that for treating the whole of the
sewage waters of Rheims in this manner, the outlay would amount to £7000
a year, besides the interest on capital expended; and the operation would
produce about 33,000 tons of manure of an inferior value. Although, then,
this agent of MM. Houzeau and Devédeix purified the water well, but at a
high cost, the process could be considered in certain special cases as a com-
plement to irrigation; but taken alone, it was evidently too costly. Irrigation
was next tried, and, in consequence of the results obtained, the Sanitary
Commission has recommended the acquisition of about 450 acres of suitable
land. The estimated cost of works, &c., is £40,000, and the annual cost of
maintenance and working about £3800.

Boilers.—At the recent Vienna Exhibition, M. J. C. C. Meyn exhibited two
of his patent high pressure boilers. This boiler consists externally of two
cylinders, of which the upper is the smaller. The furnace is half internal and
half external, and requires but little building. There is no bridge to the grate,
which communicates dire@tly through a short vertical flue with a central com-
bustion-chamber. This chamber is traversed by 76 flattened vertical water-
tubes, which form one of the principal features of the boiler. They are
wrought-iron welded tubes, with horizontal channels across their sides.
Through these tubes the water circulates from the lower part of the boiler,
and between them the flame must pass. From the roof of the combustion-
chamber a double ring of tubes leads up to the upper part of the lower shell,
the upper cylindrical shell being of such a diameter that it stands inside these
rings of tubes. This upper shell is enclosed in a smoke-box of the same
diameter as the lower shell, and made of sheet iron. ‘The ordinary water-level
is two-thirds up the height of the upper tubes, and the upper shell, therefore,
serves as a steam dome of large capacity, and has apparently been really
effettual in preventing priming. The steam is led away from the top of the
boiler through a pipe which forms atriple ring round it in the smoke-box before
it is allowed to escape.

A paper on the ‘Strength of Boiler Shells’? has recently appeared in the
columns of the “‘ Nautical Magazine,”’ in which it is stated that the Board of
Trade Surveyors have all along recognised as a fundamental principle of their
practice the following opinion, expressed by Sir William Fairbairn, in 1854,
viz. :—‘* Steam boilers of every description should be constructed of sufficient
strength to resist eight times the working pressure, and no boiler should be
worked, under any circumstances whatever, unless provided with at least
two—I prefer three—sufficiently capacious safety-valves.” It appears the
“*Galloway’s rule”? is most common amongst these surveyors, the rationale of
which is that in the absence of tests witnessed by an officer of the Board of
Trade, the strength of iron is assumed to be 48,000 lbs. per square inch in
plates and rivets ; this includes the effect of fri€tion at the joints, and supposes
the holes to be drilled, the strain to be applied lengthwise to the plate, and
the rivets to be Lowmoor, or equal to that in quality. When the rivets are
subjected to double shear, or where the strain is applied crosswise to the plate,
only 43,000 lbs. is allowed as the strength per square inch of the rivet, or of
the plate respectively. The section of the shell is taken as the length of the
boiler by the thickness of the plate; but pradtically, the length of the section
will be greater than the length of the boiler on account of the doubling of the
plates at the circumferential seams. When the double rivetting is zigzag, as
it should always be in boiler shells, the section is increased about 7 per cent
by this extra material. To give effet to this, the 48,000 lbs. was increased
about 7 per cent, or to 51,520 lbs., or 23 tons. A great deal of very valuable
information and calculations are given in this paper, relative to the proper
strength of boiler shells, but space will not admit of our following out the
subje& further at present.

126 Progress in Science. (January,

Railways.—A new line of railway 154 miles in length was opened early in
September between Bristol and Redstock. It joins the Great Western Railway
at Bristol, and is laid on the narrow gauge system. At present only a single
line of rails has been laid, but the arches are wide enough for a double line if
necessary at any future time.

The remaining portion of the Devon and Somerset Railway, between
Wiveliscombe and Barnstaple, 36 miles in length, has recently been completed.
Owing to the line running at right angles to the principal valleys and water-
courses of the district, the works are in some places very heavy, involving, in
addition to deep cuttings and high embankments, several tunnels passing
through the ridges between the valleys, and some large river viaducts. One of
these, crossing the valley of the river Tone, near Wiveliscombe, is 110 feet
high, and has four spans, each too of feet. The construction adopted being
lattice girders carried on stone abutments and piers. Another viaduét across
the valley of the river Bray, in Castle Hill Park, is 100 feet high, and has six
spans, each of 100 feet. The construction being similar to that adapted for
the Tone valley viadu@; and there is also a large iron bridge over the river
Exe, near Dulverton.

The list deposited this year at the Private Bill Office of projects for con-
sideration during the coming session embraces 395 notices, of which, how-
ever, only 244 are accompanied by plans. Amongst these 121 relate to railway
schemes, 7 to tramways, and 65 bills belong to the miscellaneous class, which
includes docks, harbours, gas and water-works, reclamation schemes, street
extensions, and local improvements. Amongst the railway projects are the
following :—A proposition to complete the Inner Circle of the Metropolitan
Railway by means of a line from Aldgate to the Metropolitan Distri& Railway
at Cannon Street. The construction ofa Metropolitan Inner Circle Completion,
and Eastern Extension Railway, by which it is proposed to form a line from
the Metropolitan District Railway in Queen Victoria Street to the Metropolitan
Railway at Aldgate, with extensions to Mile End and Bow, and junétions
with the North London and East London Railways. It also includes a new
street from King William Street to Fenchurch Street, and the widening of
the latter street. Besides these there are the following schemes affecting the
Metropolis, viz., the Metropolitan and South-Western Junction Railway
Company’s project for a line in Fulham between the authorised Hammersmith
Extension Railway at North End-Road, and their own authorised line at a
point near where it crosses the river; the Wandsworth, Fulham, and Metro-
politan Railway scheme for a line from the Wandsworth Bridge to the
authorised Metropolitan and South-Western Junction Railway at Fulham ;
the Ealing, Acton, and City Railway, which will unite the Hammersmith and
City Railway with the Great Western and Brentford line; and the Acton and
Hammersmith Railway to unite the North and South-Western Junction and
Hammersmith Extension Railways. There are several projects for improved
communication with the Crystal Palace; and most of the principal lines of
railway propose improvements in the shape of short lines and junctions
whereby increased facilities will be afforded to the travelling public.

GEOLOGY.

Physical Geology.—Baron Von Richthofen has recently described the exten-
sive sheet of mud-like strata which extends over Northern China. It is called
“Loess,” from its resemblance to the river-loam of Germany, and has a
thickness varying from 1000 to 2000 feet. There is not a trace of this forma-
tion in Southern China, and its occurrence in the northern parts produces
quite a different class of physical scenery. ‘The expanse of loess is cut up by
vast chasms, a thousand feet in depth, along whose bottoms the streams flow.
As regards its origin, after showing that it extended from the sea-level to an
altitude of 12,000 feet, the Baron stated that it must have been formed where
it is now seen, and by sub-aérial agencies. Of these, one of the chief had
been the wind and the fine dust-storms, which often lasted for many days
together, Rains also were great agents in the accumulation, He had

1874]. Geology. 127

examined hundreds of sections of the loess, and had never found any fresh-
water shells, but myriads of uninjured land shells.

Mr. W. T. Blanford has brought forward evidence of glacial action in Tropical
India in early geological times. Some peculiar beds, possibly of carboniferous
age, consisting of large boulders, embedded in a fine silt, were considered by
him as evidence of glacial action; the deposition of the boulders being due to
the agency of ice.

Professor Von Baer has recently written a memoir on the Caspian Sea, to
which Dr. Carpenter has drawn attention. Instead of the Caspian being
intensely salt, like the Dead Sea, its waters had only about one-third of the
usual saltness of ordinary sea-water. This was due to the precipitation of
the salt in the lateral lagoons, where great beds were forming. These salt
pans drained off the saline substances, and thus left the water pure.

Professor Herschel and Mr. G. A. Lebour have made some experiments
upon the conducting power for heat of certain rocks. Of all the rocks ex-
perimented upon, shale resisted heat the most, whilst the metamorphic rocks
were the best conductors. The experiments showed that the rates of conduc-
tivity of heat through rock-masses depended on the structure of the latter.
A thick bed of shale would arrest it. Hence, denudation of rocks, if carried
on to any great degree, would alter the quantity of heat conduded from the
interior of the earth to the surface. The experiments threw considerable
light on underground temperatures.

The Rev. O. Fisher, in‘a note on the “ Origin of the Estuary of the Fleet, in
Dorsetshire,” expresses his opinion that it is the eastern half of a submerged
valley, similar to, though on a larger scale than, the one which now forms the
Weymouth Backwater, its former western side having been encroached upon
and destroyed by the waves of the Weat Bay. ,;

Mr. G. H. Kinahan has lately described the Water Basin of Lough Derg, in
Ireland, and discussed the method of its formation. He points out that the
bays and all wide stretches across the basin conform with the strike of lines
of breaks or displacements in the adjoining country, while the minor features
of the coast lines are due to the weathering along minor breaks, joint systems,
or lines of bedding. It seems that in this basin all the changes in the
bearings of the different lines of deeps are connected with the strikes of the
different faults in Slieve Bernagh and Slieve Aughta, and that the islands,
rocks, and shallows are on the upthrow sides of these lines of faults.

It appears, from a despatch of the British Vice-Consul at Rhodes, that a
volcanic outburst has taken place in the island of Nissiros, one of the
Sporades, in which there existed a volcano supposed to be extin@&. Shortly
before the roth June, 1873, new craters opened in this volcano, and from them
ashes, stones, and lava were ejected; many fissures, from which hot water
flowed, were produced in the mountain, and the island was daily shaken by
violent earthquakes. From Rhodes, at a distance of about 50 miles, the smoke
rising from the new craters could be seen.

Stratigraphical Geology.—Mr. W. Whitaker (assisted by J. B. Jordan) has
prepared a large block-model of London and its neighbourhood on a scale of
6 inches to 1 mile, coloured to show the geology of the area, which includes
Hampstead, Wimbledon, Great Ilford, and Shooter’s Hill. All the superficial
deposits are represented, and the subterranean geology to a depth of 1100 feet
is shown on the sides of the model, which is divided into nine pieces. This
model is placed in the museum at Jermyn Street.

Perhaps the Sub-Wealden Exploration is the most important topic in British
geological circles. Commenced in 1872, the depth at present reached is a
little over 300 feet. The boring commences about 230 feet down in the known
Purbeck Beds, the thickness of which previously known in Sussex was some-
what over 300 feet ; according to Mr. Topley, about 230 additional feet of strata
have been made known by the boring, and in this series are some valuable
beds of gypsum. Professor Phillips has communicated the latest intelligence
in regard to the boring, stating that the lowest beds now reached are of marine

128 Progress in Science. [January,

origin, that a specimen of Lingula ovalis, a shell of the Kimeridge clay, has
been examined by him, so that the beds reached are already below the Purbeck.
He remarks that the great upper clays of the oolites have been touched
without encountering shore sands or shelly oolites,—no Portlandian rocks
have appeared. Clay deposits may be found for a considerable depth; there
may be no triassic beds, and he thinks that the paleozoic rocks may be reached
at no enormous depth, and with no unusual difficulty.

Mr. Whitaker has recorded the discovery of Thanet Sand on the northern
outcrop of the London Basin, near Sudbury, where it had not previously been
observed.

Palzontology.—Dr. Von Mojsisovics has published the first part of his
geological investigation of the neighbourhood of Hallstatt, in which he
describes the remains of Cephalopoda obtained from the Zlambach and
Hallstatt beds. He indicates repeatedly, especially in connection with the
genera Lytoceras, Pinacoceras, Sageceras, and Arcestes, that he can by no
means arrange the Goniatites as a distin& generic series in opposition to the
Ammonites. The triassic representatives of the above-mentioned genera are
most closely related in all essential peculiarities of organisation and habit to
Goniatitic predecessors; the Ammonites from the Permian sand-stone of
Artinsk, Waagen’s Permian Ammonite from the salt range of the Punjab, and
certain triassic forms partially bridge over the gap which still exists between
the older Goniatites and the Ammonites of the Trias. By far the greater part
of the genera of Ammonites occurring in the Alpine Trias have their roots in
the Palzozoic Goniatites ; and some of them may apparently even be traced
back into the Upper Silurian formations. The greater part of these Paleozoic
genera become extiné& in the Upper Trias, when they attain the height of
their development, but at the same time show signs of senile degradation,
analogous to the phenomena observed during the gradual extinction of the
later Ammonitic types in the Cretaceous period.

Professor W. H. Flower has described a new species of Halitherium from
the Red Crag of Suffolk. It is of especial interest as furnishing the first
recorded evidence of the existence in Britain of animals belonging to the order
Sirenia. This new species presents many characters common to the Manati
and the Dugong.

PHYSICS.

Microscopy.—A new freezing microtome, for facilitating the cutting of thin
sections of soft tissues, has been contrived by Dr. William Rutherford, Pro-
fessor of Physiology in King’s College, London. The construction of the
machine will be easily understood by reference to the cuts. Fig. 2: A, hole in
the brass plate (B); c, tube; D, screw; E, indicator; F, screw for fixing the
machine to a table; G, box for holding the freezing mixture; H, tube for per-
mitting the water to flow from the melting ice. Fig. 3: Vertical section.
The hole A is shown containing a piece of tissue, and the box G containing the
freezing mixture; K, a movable bottom to the hole A; R, transverse section of
the knife used in making the se@tions: the other letters the same as in Fig. 2.
The tissue to be frozen and cut is placed in the tube (A). The section is made,
as in the ordinary instrument for cutting wood sections, by gliding a knife
horizontally through the tissue projecting above the level of the plate (Bs).
The thickness of the section is regulated by the indicator (gE). The machine
may be employed for two objeé&ts :—For cutting tissues hardened in the ordi-
nary way, by chromic acid, &c.; and second, for cutting tissues hardened by
freezing. The second method of using the machine will be more readily com-
prehended after a description of the first, which is simply this:—Place a
portion of hardened tissue in the hole a, and pour around it a mixture of
paraffin (5 parts) and hog’s lard (1 part), melted by the aid of a gentle heat.
Or the paraffin mixture may be first poured into the hole, and the piece of
tissue afterwards introduced, and held in any desired position, by means of
forceps, until the paraffin becomes sufficiently hard. In order that the paraffin
may fairly support the tissue, it is necessary that the surface of the latter be

1874.| Physics. 129

dry. This is easily accomplished by leaving it exposed to the air for some
time, either with or without previous immersion in spirit. When the machine
is used for the second obje&—that is, for freezing—the following directions are
to be attended to:—Surround the freezing-box with two or three layers of
flannel, and screw the machine to atable. Unscrew the movable bottom, or

Fie. 2.

Gr tes rated MEE PPLE,

Paz

Poy han OW
AW Ase cae

AS 2

TOD

wats
OTEG

DMG,

plug (k, Fig. 3), and pour methylated spirit into the tube (c); oil the side of
the plug; replace it, and screw it down to any desirable extent, and there
leave it. The objeét of this is to prevent the screw from becoming fixed by
_the freezing. The spirit which has come above the plug (xk) must be thoroughly

VOL. Iv. (N.S.)

130 Progress in Science. (January,

removed by means of a towel, and the small slit at the margin of the plug
carefully closed by means of hog’s lard, which should be spread in a thin layer
around the entire margin of the plug, to prevent the spirit from in any way
reaching the cavity above the plug. The screw (p) must not be touched until
after the freezing is completed, in case this accident occur. The tissue to be
frozen, together with an imbedding fluid, are placed in the hole. For ordinary
purposes a solution of gum arabic may be employed, prepared in the following
manner :—Add to 1o ounces of water, 2 drachms of camphorated spirit and
5, ounces of picked gum arabic; when the gum has dissolved, strain the fluid
through calico, and preserve for use in a corked bottle. The gum when frozen
can be sliced as easily as a piece of cheese. The gum or other fluid should
be first placed in the hole of the machine, and when a film of ice has formed
at the periphery the tissue should be introduced and held against the advancing
ice until it becomes partially frozen. In this way a portion of tissue may be
secured, in any position, for the process of section. Lay a piece of gutta-
percha upon the brass plate (B) so as to cover the cavity containing the tissues
and prevent the entrance of heat, and the accidental entrance of salt from the
freezing mixture. Place in the freezing-box (c) alternate quantities of finely
powdered ice and of salt, and take care they are pushed round the tube of the
machine, and also that the tube (H) is kept open, in order to permit of the con-
stant egress of the water from the melting ice. The freezing can be most
rapidly effected by the addition, at short intervals, of ice and salt, and by
repeatedly stirring the mixture, in order that the escape of water may be
facilitated. It is possible, especially in winter, to have the tissue frozen too
hard to permit of its being readily cut. It splinters when it is too hard.
This is prevented by discontinuing the further addition of the freezing mixture,
or by dropping water or a three-quarter per cent salt solution, at the ordi-
nary temperature, on the surface of the frozen tissue, or by heating the razor
slightly. With regard to the cutting tool, it may be stated that a razor
answers perfectly well for all ordinary purposes. ‘The blade should always be
hollow on both surfaces (R, Fig. 3). It is a mistake to employ a flat knife, for
it is scarcely possible to keep the surface of the brass table of the machine
smooth enough to permit of the knife lying quite flat. The knife should be
pushed obliquely through the tissue, which should be cut at one sweep. This
is not possible with a frozen tissue, if the ice be too hard. For an unfrozen
tissue embedded in the paraffin the knife should be wetted with methylated
spirit. Inthe case of freezing it is not necessary to wet the knife, for the
melting ice does so readily. The machine has been made by Mr. Baker, of
High Holborn.

Mr. John Barrow* recommends naphthalin as a material for embedding soft
tissues for the purpose of cutting sections. The advantages claimed for
naphthalin over wax and other substances are—A low fusing-point, absence of
contraction, the minimum of injury to the edge of the knife, and very ready
solubility after cutting in benzol or spirit, so that the substance is at once
removed from the section without injury.

Mr. F. H. Wenham, at the October meeting of the Royal Microscopical
Society, exhibited, under the microscope, a roughed pattern on a piece of
glass produced by the American ‘‘ sand-blast,”’ remarking that the microscopi-
cal appearance of the “ greyed”’ surface is quite distin& from that of ordi-
nary ground glass. Observations under a low power give some insight into
the modus operandi, It was stated, at the late meeting of the British Associ-
ation, in the discussion that followed the description of the process, that a
large crystal of corundum was speedily perforated with ordinary sea-sand and
a blast-pressure of 300 lbs. per square inch. Corundum is several degrees
beyond emery in hardness, approaching near to that of the diamond. But it
was further stated that, under the conditions named, diamond itself became
speedily worn away. At first sight it seems extraordinary that the hardest
known material should quickly be destroyed by one considerably softer. The

* Manchester Literary and Philosophical Society, Microscopical and Natural History
SeGtion, April 21, 1873.

1874 Physics. 131

microscope indicates that this is caused by the force and velocity of impaé@ ;
it is not a grinding process at all, but a battering action, similar to that of
leaden bullets against a block of granite. A polished glass surface exposed
for an instant to the sand-blast shows an aggregation of points of impad,
from which scales of fractured glass have broken away in an irregular radial
direction. It appears as if a pellet of glass had been driven in by the collision
of the sand, and the wedge-like action thus set up had driven away the sur-
rounding glass. All these spots or indentations, when tested by the polari-
scope, show a coloured halo round each, proving that the glass surface is
under strain and ready to yield to further fracture. The action therefore is
not so much due to the hardness of the striking particles as to the force and
velocity of impact. This is sufficiently great to destroy the cohesion of the
surface of the material operated upon. ‘The external layer is carried against
the under stratum, and the material is crushed and disintegrated by a portion
of its own body. :
Mr. William Webb, whose minute writings on glass are so well known
to microscopists, disputed the reality of the finer bands of lines on
Nobert’s test-plate, on the ground of the tool cutting away the surface
of the glass, and leaving, as he showed by certain diagramatic sections, irre-
gular jagged furrows. Dr. Woodward, of the Army Medical Museum, Wash-
ington, in reply, reminds the readers of Mr. Webb’s paper, that there is a
physical reason which compels us to believe that the first fifteen bands, at
least, of the nineteen-band plate are composed of real and distiné lines, and
that the distance apart of these lines must approximate very closely to what
was intended by Nobert. When the bands of Nobert’s plate are illuminated
by oblique light, and are looked upon from above with a low power (too low
to show any of the lines), each band appears as a smooth coloured stripe.
From the known wave-length of the colour seen, and the angle of the incident
pencil, the distance which the lines of any band must a@tually be apart can
be computed by the well-known formula for the spectrum of gratings enunci-
ated by Frauenhofer, and the distance thus obtained agrees with that at which
Nobert ruled the lines. On the other hand, the angle of the incident pencil
being known, and Nobert’s given distance being assumed to be true, a table of
wave-lengths for the different colours may be calculated, and the wave-lengths
thus deduced agree substantially with those computed by other means.
Nobert has discussed the whole matter in the 58th volume of ‘ Poggendorff’s
Annalen” (1852). His discussion leaves, in the opinion of Dr. Woodward,
no room for the possibility of a doubt of the objective reality of the lines up
to the fifteenth band. Dr. Woodward calls attention to the fa& that this
reason is altogether independent of our ability to resolve the lines with the
microscope. In fad, it enabled Nobert to know that his plates were corre@ly
tuled long before the resolution of any but the coarsest bands had been
effe@ted. Asno spectral colour is obtained in the bands finer than the fifteenth,
the formula of Frauenhofer cannot be applied tothem. In fac, the formula
demonstrates that if these bands are actually ruled, as claimed, they can give
no spectral colour. Dr. Woodward has no hesitation in expressing the opinion
that the four higher bands (sixteenth, seventeenth, eighteenth, and nineteenth)
have also an objective reality. He bases this opinion upon the comparison
of their optical appearances, as seen with the best glasses, with the appear-
ances of the lower bands (especially those from the ninth to the fifteenth).
These appearances are quite the same in both cases, and, as similar results
follow similar causes, he infers the existence of real lines in the four higher
bands, since he knows they exist in the others. Dr. Woodward has recently
examined two new test-plates by Nobert,—the first ruled for Professor Barnard,
of Columbia College, the second for the Army Medical Museum,—in which
the maker has attempted to rule lines twice as fine as those of the nineteenth
band. These plates have twenty bands. The first ten correspond respectively
to the first, third, fifth, seventh, ninth, eleventh, thirteenth, fifteenth, seven-
teenth, and nineteenth of the old plate. The lines in the second group of ten
bands purport to be ruled at the following distances apart:—The eleventh
band, ,y$y5th of a Paris line; the twelfth band, y,},5,th; and so on up to the

Fic. 4.

Fia. 5.

132 Progress in Science. (January,

twentieth band, lines of which are said to be y3,,th of a Paris line apart.
These new bands have not at present been resolved.

Mr. J. J. Monteiro, ina letter to the “‘ Chemical News,”* gives some account
of the habits of the ‘plantain eaters” (Turacus albo-cristatus), the birds
from the feathers of which the colouring matter turacin was extracted by
Professor Church, and which is distinguished by its remarkable two-banded
spectrum. These birds are common on the West Coast of Africa, and in the
part known to the writer, viz., from Loango, in 5° S. lat., to Fish Bay, in 15°
S. lat., they abound. Over the whole country mentioned, and for a consi-
derable distance inland, copper is found, most abundantly distributed, as mala-
chite or green carbonate; specks of the green mineral are everywhere to be
found. Mr. Monteiro considers it highly probable that the birds swallow
small particles of the cupreous substance with the gravel, &c., so commonly
taken by all birds. This may account for the large quantity of copper disco-
vered by Professor Church in the feathers of these birds. Mr. Sidney Lupton
also remarks+ that two green love birds (Melopsittacus undulatus) were in the
habit of pecking at the bars of their cage or any brass-work accessible to them.
The feathers of these birds also yielded traces of copper. The spectrum of
the green feathers had not been examined. The lower band of the turacin
spectrum (Fig. 5) corresponds in position, although not in extent, with the band
of ruby glass (Fig. 4): extent of absorption, however, is in many cases de-

IRE

pendent upon the intensity of the coloured medium, many bands, as those of
the aniline dyes, being easily made to absorb to a greater or less extent, ac-
cording to the amount of dilution or the thickness of coloured medium through
which the light is allowed to pass. (The bands between the Frauenhofer
lines, extending half-way across the upper spectrum, are those of nitrate of
didymium, and, from their sharpness and convenient distribution, are conye-
nient in mapping spedtra by artificial light).

ELectricity.—Mr. Casselberry, of St. Louis, has been experimenting for
several years with voltameters. He finds as the result that two voltametric
apparatus (of the ordinary kind) connected together, not in series, but with
their oxygen and hydrogen eletrodes attached by wires, the oxygen electrodes
to the positive, and the hydrogen electrodes to the negative pole of a battery,
that there is then generated in each voltameter an equal quantity of gas to
that generated in only one voltameter with the same battery. The experi-
ment is borne out by the law of derived circuits, the second yoltameter being

* “ Chemical News,” vol. xxviii., p. 201.
+ Ibid, vol. xxviii., p. 212.

—————F

1874.] Physics. 533

in effe@t a derived ele@trolytic circuit to the first. Should the experiments (and
they are most carefully recorded) stand the test of general experience, the
sequence of great importance in the practical deposition of metals would
appear to follow naturally and immediately.

The experiments were repeated with a magneto-eleftric machine, with
results precisely similar to those obtained with the battery.

The electric current has again been utilised for the purposes of ascertaining
longitude, this time of Harvard observatory. The results show the difference
of time between Harvard and Greenwich to be for the following years :—

Hrs. Mins. Secs.
IGS167) Go you) ote sop 4 44 31°00
WSO. ag hd vod. po 4 44 31°05
UT 56 folo 4 Boe OC 4 44 30°99

The mean of which is 4 hrs. 44 mins. 3r‘or secs. The close agreement of
these results indicates a very near approximation to the truth, and this funda-
mental longitude may now be considered as settled. Adding to the above
value the difference in time between the Washington and Harvard observatories,
23 mins. 12°12 secs., we get for Washington 5 hrs. 8 mins. 12°12 secs.

In America interesting le@ures upon the system of fire, burglar, and other
alarms as laid down by the American Distri&t Telegraph have been delivered.
Particulars will be found in the ‘‘ Journal of the Franklin Institute.”

In natural science electricity has again made progress. Dr. Burdon-
Sanderson has investigated the ele&trical phenomena which accompany the
contractions of the leaf of Dionea muscipula, and he has demonstrated their
collateral character with those of nerve and muscle.

INVESTIGATION OF THE FLUORESCENT AND ABSORPTION SPECTRA OF THE
URANIUM SALTS.—President Morton and Dr. Bolton, after briefly noticing
the labours of their predecessors in this department of research, describe the
methods employed, which do not differ from those of Stokes and Becquerel,
except in small details, and the means at their disposal for securing accuracy
in the measurements.' A variety of uranium compounds were specially pre-
pared, and their spectra, both of fluorescence and absorption, were carefully
mapped out and measured. Illustrations are given showing some of the most
charaéteristic of these spectra. Very charaéteristic differences were found
between the spectra of certain salts, and in a number of cases one body can
be readily discriminated from another by this means. Indeed,inthis investiga-
tion impurities in many commercial compounds of uranium were thus detected,
and, in other cases, the progress and consummation of achange in composition,
or in the formation of a compound, was watched and recognised with the
greatest ease and precision. In almost every case there is a tendency of the
light to fade off in the bands towards one side more gradually than towards
the other. In nearly all spectra this graduation is greatest towards the less
tefrangible end of the spetrum. The character of any one band is, as a rule,
a type of all the bands of a spectrum; but to this a remarkable exception is
found in the double acetates of uranium generally, and especially in the
sodium salt whose fluorescence is the brightest. In the speétrum of this salt
the first four bands at the lower end of the speétrum in the orange and red
differ entirely in chara@er and spacing from the rest, except the fifth, which
seems to be in a transition state. It is also true, as a rule, that double salts
with the same acid have bands of a like charaf&ter; but to this also there are
decided exceptions, and it is by no means true that all salts with the same
acid have like bands. This chances to be true in the case of the sulphate and
normal double sulphates, but in the case of the acetate and double acetates,
fluoride and double fluorides, chloride and double chlorides, as also among the
numerous hydrates of the sulphates, it fails to maintain itself. Nothing
could well be more unlike than the spe&ra of uranic oxychloride and the
potassium chloride. The question arises, how far the spectra of substances
are constant, and in what way a change of spectra is to be interpreted. The
authors find that no substance has its spectrum changed by anything which
does not affect its composition, excluding the effe@& of heat, and certain cases

134 Progress in Science. (January,

in which a substance has been caused to give a continuous spectrum in place
of its normal one. We may, therefore, ascertain in many cases whether under
certain treatment a body has or has not suffered a change in composition, and
trace such a change step by step.

Absorption Spectra.—There are in the uranium salts two sorts of absorption
—one direétly related to their fluorescence, and the consequence of the fact
that those rays which excite fluorescence must themselves disappear, their
motion taking that other form; and the other an absorption having no imme-
diate relation to fluorescence, but representing rays of the spectrum whose
motions are converted into heat or some other form of force not sensible to
the eye (Phil. Trans., 1852, p. 520). Absorptions of the first class are best
studied by dire& observation, combined with a process closely allied to that
described by Stokes as his third method, which consists in throwing a pure
spectrum upon a screen of the substance in question, or upon the vertical side
of a tank containing a solution. With the solid screen, the location of
general maxima of fluorescence will correspond with maxima of absorption,
and with the tank the absorption can be dire@tly seen as embodied in dark
blades or triangular masses of shade running into the tank (as seen from
above) from the side away from the light. These appearances will often
indicate the existence and relative intensity of absorptions, whose exact
locations we can measure by examining the transmitted light directly with the
spectroscope. The spectra of absorptions not diredtly related to fluorescence
are, as a rule, best studied by transmitted light. The difference between
different salts as regards their apsorption-bands is very great; and, while in many
cases solution has a vast effect upon fluorescence, it sometimes produces but
little effet upon the absorption-bands. In other instances, however, very
marked changes occur, and, when these are followed out to their legitimate
conclusions, they lead to some very remarkable results. Thus, if we examine
the absorption-spetra of the uranic acetate and the various double acetates,
we shall find that in the solid state they present great variety in the exact
location of the bands, but in solution we have exactly the same spectrum for
all. The conclusion therefore presents itself, that in solution all are reduced
to the same state, which could, of course, only be by the breaking up of all the
double salts. Indeed, from this, supported as it is by other observations, we
do not hesitate to conclude that xo double acetate can exist in solution in water,
but must break up into its two single salts. Nor do our conclusions stop here,
but we must reserve others until some of the facts on which they are founded
have been described. A similar experience leads us to a like conclusion in the
case of the sulphates, oxychlorides, &c. Attention was drawn to the fact of
such displacement by one of us in September of last year, but its true
bearing has only been perceived recently, since a large number of observa-
tions have been accumulated. A change of character, rather than of position,
produced by solution in the absorption-spectrum of didymium sulphate, was
observed by Bunsen in 1866 (see ‘“ Pogg. Ann.,” vol. cxxxviii., p. 100, and
“Phil. Mag.,” 4th series, vol. xxxii., p. 181). The position of the band of
uranium nitrate, while unaffected by solution in water, is notably changed by
other solvents, as the following table will show :—

Bands. I. 2: 3. 4. 5. 6.
Glycerin’ 3s) f 3.19 <tet (87:6 96'0 107'8 123'0 136'0 148°6
Water Witte os 889:8 98'5 108'5 118°7 129°5 142'0

Alcohol. 9/4 cit? Gi.42i— 99°4 I1I'7 — —
Hydrochloric ether... — 99°4 110°8 123'7 — —
Ether 2 Lhe) Se 1000 112°6 1230 — _
Aceticiether:i..3..-. *“—: 10zf0 DII'7 128'0 135°4 —

Effects of Heat.—It was observed by Stokes that canary glass and the
nitrate of uranium had their fluorescence reduced by heating, and that at a
temperature much below redness their influence upon light in this respect was
quite suspended. In the solutions of nitrate of uranium all fluorescence was
extinguished near 212°F. The substance regained its fluorescence on cooling.
He also remarked that no such action appeared in fluorescent vegetable solu-

1874.1 Physics. 135

tions. Gladstone finds, as a rule, the effect of heat is equivalent to a concen-
tration of the solution, and amounts to an increase in the amount of absorption.
In a paper ‘“‘ On the Change of Colour produced by Heat in Certain Chemical
Compounds,” E. J. Houston pointed out the curious and novel fad, that, in all
cases where no chemical change was involved, solutions, as well as solids,
changed to tints lower in the spe&trum on the application of heat. The loss
of fluorescence in a few substances when heated appears to extend (with cer-
tain limitations) to all the uranium compounds, both in their solid state and in
solution. We find that in the case of the anhydrous ammonio-uranic sulphate,
fluorescence is sensibly diminished at 140° C., and is almost destroyed at
260° C. The hydrate does not show any marked loss of fluorescence below
the point at which it begins to part with its water. The same is true of the
potassium sulphate. The sodio-uranic acetate is much more sensitive.
Experiments were made with it and other salts. It was observed that at
about 50° C. the brightness of the fluorescence was reduced, and that the
uppermost decided band (81°8) lost its distin@tness. At about 116° C. it
seemed to reach aminimum. At that temperature the uppermost band had
vanished, and the lower ones were too faint for measurement. No further
change was noticed on carrying the temperature to 150°. Solutions are still
more sensitive. The authors next enter upon a detailed examination of
various uranium compounds, from which we seleé the following passages : —
Uranic Acetate (normal), U203;3C,H303+2HO.—This substance fluoresces
very brightly, different specimens, however, differing, probably from the pre-

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sence of minute traces of foreign matter. Its solution yields a very bright
fluorescence, which is reduced by the addition of a trace of alcohol, ether,
glucose, or sucrose, and is destroyed by a very small amount of hydrochloric
acid. The fluorescent light of the solution yields a continuous spectrum,

136 Progress in Science. (January,

When examined with the spectroscope its fluorescent light emitted by the
solid yields a sys ae m of eight bands. Of these the 1st and 7th are very

Fic. g.

i
a /

Fic. 12

emeneeerncema
pra na pe

ee mm Mh ‘| i ~
=e ne

faint, and the 8th only appreciable with a strong light and wide opening to the
slit of the spectroscope. The brighter bands show a very setae termination

1874.) - - Physics. 137

towards the more refrangible end, and shade off gradually so as to look like
pieces of moulding illuminated from the violet side of the spe@rum. No. 1
in Fig. 7 will give an idea of this, as well as of the positions of the various
bands. By turning the spectroscope obliquely on the bottle containing this
salt, an absorption-band at 107 can be distinguished with ease, but none above
this can be made out, and, as regards this matter, the strongest contrast exists
between the uranic acetates and its double salts. By

crushing a few grains to a fine powder, with a little Fic. 13.
water, between slips of glass, we may observe the
absorption-bands by transmitted light with facility,
and get a spectrum of a curious character as regards
the irregular spacing of its bands. No. 1 of Fig. 8
will give a good idea of this. Another noteworthy
point is the very strong general absorption, which
almost obliterates details of the spectrum, and makes
it impossible to recognise any bands above one at
about 135. In solution this general absorption is
increased, and the absorption-bands are blended so
that little can be done in the way of measuring them.
If we make a solution of the neutral acetate in water,
and examine its absorption, we shall find a faint band
at about 105, and some indication of one at about 117,
but a very heavy general absorption over the entire
region above the first-named band obliterating all
variations of shade. The addition of a little acetic
or other strong acid will, however (while destroying
the fluorescence of the solution), clear up its absorption-
spectrum in a remarkable manner, giving us such a
one as is shown at No. 3 of Fig. 8, which we have
reasons for regarding as the absorption-spectrum of
the double acetate of uranium and water.

Anhydrous Uranic Acetate, U203;C,H303.—If this
normal uranic acetate is dried, at a temperature of
100° C., for some hours, it becomes opaque, and of a
lighter and purer yellow tint, and is found to yield a
fluorescent-spectrum, the bands of which are like those
of the normal salt, but are all displaced downward
in the spetrum. No. 2 of Fig. 7 will show the
arrangement of these bands. The brightness of the
fluorescence is very much reduced, and the first and
last bands could not be made out with the apparatus
at present in use. By inclosing this substance in
dry powder, between slips of glass, its absorption-
spectrum was observed with transmitted light, and is
shown at No. 2 of Fig. 8. The general absorption is
greater in this than in the case of the normal uranic
acetate.

The Double Acetates—These bodies give spectra
which, whilst differing remarkably from that of the
single acetate of uranium, agree strikingly among
themselves. The fluorescent spectrum of the sodio-
acetate of uranium is a type of a perfect double acetate
of spectrum. All the double acetates show their
absorption spectra with very great ease. The
arseniates appear peculiarly fixed and inflexible in the
relations under review. The four compounds ex-
amined exhibit but one spectrum of fluorescence and one of absorption. The
charaéteristics of the former are seen in Fig. 9, No. 1, and those of the
latter in Fig. 10, No. 1. The double carbonates of uranium fluoresce faintly,
showing a chara¢ter like that of the less brilliant double acetates. See

VOL, IV. (N. S.) s

138 Progress in Science. (January,

Fig. 9, No. 2. The neutral oxychloride has avery great general absorption, and
shows some bands, but is almost devoid of fluorescence. The uranic oxyfluoride
gives a spectrum generally resembling the acetate, normal sulphate, &c., and
shown in Fig. 11, No. 2. The absorption-spectrum is likewise well marked,
and is shown in Fig. 12, No. 2. When dissolved in water and acidulated
with hydrofluoric acid, it yields the absorption-spe@rum No. 3 of Fig. 12.
Of the double oxyfluorides the potassium salt is the most brilliant, and is
represented in Fig. 11, No. 1, its absorption-spectrum being shown in Fig. 12,

Fic. 14.
/

ili vt oui dl mnt

meee fT

i |

7 ae
i

i

No. x. Of the fluorides examined none show any fluorescence, but their
absorption-spectra are well worthy of notice. That of the uranous salt is
shown in Fig. 13, No. 2, and that of the potassio salt in Fig. 13, No. r. Uranic
formiate gives no fluorescence, and shows an absorption-spectrum with faint
bands. The uranic nitrate fluoresces brilliantly, yielding what may be called
the normal uranic spectrum. It shows an absorption-spetrum of well-
marked, regular bands. All the oxalates yield absorption-spectra, which are
very well marked, and seem identical, carrying out the idea above suggested

Fic. 15.

vi
zz |

a |

it ai
a
i

¥

as to the breaking up of double salts when dissolved. The phosphates, like the
arseniates, show a remarkable fixity of spectrum, but the absorption-spectra
present a variety of forms. The absorption-bands of the neutral and acid
sulphates are shown in Fig. 14, Nos. 1 and 2, and in 3 we find the bands of
any other uranic sulphate as yet examined. It would seem with the sul-
phates as with the acetates that all are reduced to the same condition when
in solution. Fig. 15 shows the absorption-spectra of the following double
sulphates :—(1) ammonio-uranic sulphate; (2) ammonio-diuranic sulphate ;
(3) magnesio-uranic sulphate; (4) rubidio-uranic sulphate; (5) sodio-uranic
sulphate; (6) thallio-uranic sulphate. For a detailed description of the
characteristics of the various spectra here mentioned the reader is referred to

1874.] Technology. 139

the papers as communicated by the authors to the “Chemical News,” and
which must be regarded as a valuable contribution to chemical and physical

science.
TECHNOLOGY.

An instructive paper by Capt. G. A. Strover, of Mandalay, on the Metals
and Minerals of Upper Burmah, appeared in the ‘‘ Chemical News ” of O@ober
to. Gold, silver, copper, iron, lead, tin, platinum, graphite, coal, jade and
amber, sulphur, saltpetre, rubies, sapphires, garnets, salt, petroleum, india-
rubber—all seem to abound. The sulphur is found in efflorescent salts, and is
manufactured from metallic sulphurets. The mode of extraction is illustrated
below in Fig. 15. Common chatty-shaped vessels are made on the spot from

Fic. 15.

Sar y i, & Ve ze— wie 4 = os
Sa WAZ. A= NE a tea a

the soft blue clay in which the ore is found. The larger vessel is filled with
broken ore, and placed on a fire, a clay retort being fitted to the top, and com-
municating with the smaller vessel. The sulphur is thus sublimed and
condensed as shown, after which the retort is broken, and a hollow tube of
flowers of sulphur extracted therefrom which is superior to that condensed in
the vessel.

The following improved forms of gas generator were described at the
Bradford Meeting of the British Association by Mr. C. J. Woodward,
B.Sc. :—Two forms of apparatus had been made. The first, shown in section
in Fig. 15, and intended for large supplies of gas, consists of a circular stone-
ware vessel, A A, holding 3 or 4 gallons, and surmounted by a large cylindrical
pipe, B. In the top of the vessel is a tubulure, c, to which is fitted a glass
cylinder containing the granulated zinc or other gas-generating material. To
the opening of the upper end of the glass cylinder is attached a cork and the
delivery tube,p. A plug, E, can be raised or lowered by means of a cord,
which, passing over pulleys, terminates in a ring, F. It will readily be seen in
what way the apparatus is used. As seen in the figure, the plug, &, is
immersed in the acid with which the stoneware jar is filled, and the liquid has
risen by displacement into the glass cylindrical vessel, coming in conta& with
the gas-generating material, where of course the evolution of gas goes on.
When it is desired to stop the flow of gas, the plug, £, is raised, the ring, F,
being slipped over the stud,G. The acid now retreats from the glass cylinder,
and the gas-generating material is left dry. At any time, then, when gas
is wanted, it is only necessary to release the ring, F, the plug, £, falls into
the acid, the zinc, marble, &c., becomes covered, and the flow of gas begins
and can easily be arrested in the manner first described. The second form of
apparatus, used when only a small supply of gas is wanted, consists of a
Wolft’s bottle, a, Fig. 16, to one tubulure of which is fitted a cork carrying a
glass tube and piece of caoutchouc piping, B. This pipe, B, can be closed by
a pinch-tap, c. To the other tubulure of the Wolff’s bottle is fitted the
adapter, D, in which is placed the zinc, marble, or other gas-generating
material. To the upper end of the adapter is fitted a cork and tube, E, serving
for the escape of gas, which is washed at F, and then passes on foruse. To
use the apparatus, the Wolff's bottle is charged with acid up to the level indi-
cated in the figure. Then, on blowing air by the mouth by means of the tube,
B, the pinch-tap, c, being open, acid is forced into the adapter, D, and gas at

140 Progress in Science. [January,

once comes off. The pinch-tap, c, is now closed, and the compressed air in
the Wolff's bottle still keeps the acid in the adapter. When it is desired to
stop the flow of gas, the pinch-tap, c, is opened, the compressed air escapes,

Fic. 16.

and the acid in the adapter falls, leaving the gas-generating materials dry.
Should the blowing of air by the mouth be deemed objectionable, an air-ball
may be attached to the pipe, B. A safety-tube, c, is used, in order to prevent

Fic. 17.

the liquid from the wash-bottle being drawn over on stopping the supply
of gas.

ErkaTA.—Owing to postal delays the following errata did not arrive at the
printing office in time for correction :—Page 2, line 3 from top, for “external”
read “nocturnal.” Page 5, line 2 from top, for “Mars” read “mass.”

Page 35, lines 2 and 18 from bottom, for “ Jan. 22nd, 1872” read “ Nov. 13th,
1$71.”’

a

q

i

“

a

IMPROVED SPECTRUM APPARATUS.

JOHN BROWNING begs to call the attention of the scientific public to the fact that he
has re-modelled and greatly improved nearly the whole of his specialities in Spectroscopes
within the last year; more particularly he would mention his MINIATURE SPECTROSCOPE, the
Direct-Viston SPECTROSCOPE, with Micrometric Measuring-Apparatus, and his UNivERSAL
Automatic Spectroscope. JOHN BROWNING can now supply one of these instruments
with a dispersive power equal to eleven flint-glass prisms, and so compac¢t that it can be easily
adapted to a 4-inch Refracting Telescope.

COLONEL CAMPBELL’S NEW SPECTROMETER.

By the aid of this contrivance an unskilled observer can map any spectra without taking readings.

t

NS a RS ge hel og a i 8
Optical and Physical Instrument Maker to the Royal Observatory, &c., &c.,
63, Strand, W.C., and 111, Minories, London, E.

ESTABLISHED I00 YEARS.

An Illustrated Descriptive Ca-alogue of Spectroscopes, 18 Stamps. List of Spectroscopes
Free by Post.

BROWNING’S

NEW LARGE AUTOMATIC ELECTRIC LAMP.

aa

In this Lamp both carbons are moved by the elec-
tricity of the battery employed (without the aid of
clockwork) ; the light remains uniform in height, and
more steady in action than any of the expensive regu-
lators previously introduced. Any number, from 20
to 50-quart Grove's Cells, or 2-quart Bunsen’s, may
be used with this Lamp. Price £8 8s.

Joun BrowninG begs to announce that he has
prepared, with peculiar care, a great number of Dia-
grams to illustrate recent discoveries in Spectrum
Analysis and other branches of Observational
Astronomy. These Slides can be had either plain or
exquisitely coloured. Prices—3s. 6d. plain, and from
4s. 6d. to tos. 6d. coloured. A list of subjeéts priced
on application.

Photographs of Microscopie Objects for the Lantern,
3s. each. Lists on application.

Ecectric Lamps, either separately or with Lan-
tern Apparatus, for Public Exhibitions and Lectures.
for showing Diagrams or Spectrum Experiments on
Screen, or for Illuminating Halls or Buildings, on
hire, either in town orcountry. Qualified Assistants
sent if desired. Terms on application.

JOHN BROWNING,

OPTICAL AND PHYSICAL INSTRUMENT
. MAKER

To Her Majesty's Government, the Royai Society,
the Royal Observatory, &c., &c.,

111, MINORIES, LONDON, E.

Established 100 yeers.

NU ea

7

A

CONTENTS. OF No. XLI.

I. The Saturnian Syitcin :
II. On the Relation between Refracted and Diffracted Spectra.
III. Observations on the Optical Phenomena of the Atmo-
sphere. ¥
IV. Recent Changes in British Artillery Matériel.
V. The Geological Survey of the United Kingdom. =
VI. Gall’s Discovery of the Physiology of ge Brain, and its
Reception.
VII. Economy of F uel.
VIII. Notes of an Enquiry into the Phéwoneea be Spiritual, Ss
during the years 1870-73.

2

NOTICES OF SCIENTIFIC WORKS-

tyndall’s “* LeGtures on Light.”

Lockyer’s ‘‘ The Spectroscope and its Applications.” ce
Proétor’s ** Light Science for Leisure Hours.” i ee

Thorpe’s “ Quantitative Chemical Analysis.” see
Shelley's ‘‘ Workshop Appliances.”
Latham’s “ Sanitary Engineering.” ae.
Baird’s “‘ Annual Record of Science and Industry 1 for 1872.” ;
Gillmore’s ‘‘ Report on Béton Aggloméré.”

Gillmore’s ‘‘ Practical “reatise on Limes, Hydraulic Cements, and —
Mortars.” “ ; =
Bain’s ‘* Mind and Body. : ra
Sir John Lubbock’s ‘ Cetie and Metamorphoses of Insects.” | {fer
Fox's “ Ozone and Antozone.” be ; oe
” f

Atkinson’s “ Ganot’s Elementary Treatise on ite
Jenkin’s ‘* Eleétricity and Magnetism.” s
Althaus’s “ Treatise of Medical Electricity.” a YoY
Saltzer’s ‘* Treatise on Acoustics.” mba a
Blackley’s ‘‘ Experimental Researches on the Causes and Nature of

Catarrhus Estivus.” .
Baker's ‘‘ Long Span Bridges.”

.
“a . * Neer Ae

ley === = ¥

PROGRESS IN WCIENCE,
(Including the Proceedings of Learned Societies at Home aie Abroad, and :

Notices of Recent Scientific Literature ). igs
MINING. MINERALOGY. Puysics.
METALLURGY. ENGINEERING. TECHNOLOGY,

GEOLOGY.

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— 12,607 THE QUARTERLY

JOURNAL OF SCIENCE,

AND ANNALS OF } |; |\ {\ }i

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Leay :

MANUFACTURES, AND fil eeont Gay

EDITED BY

WELLEAM’ “CROOKES, F. RS: ,: ec:

Me

No. XLII.

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OFFICES OF THE QUARTERLY JOURNAL OF SCIENCE,
3, HORSE-SHOE COURT, LUDGATE HILL.

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ART.

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(The Copyright of Articles in this Fournal is Reserved.|

CONTENTS .OF- No... XEL.

On THE FLINT AND CHERT IMPLEMENTS FOUND IN
KENT’s CAVERN, NEAR Torquay, DEVONSHIRE. By
W. Pengelly, F.R.S., &c.

On RECENT EXTRAORDINARY OSCILLATIONS OF THE
WATERS IN LAKE ONTARIO AND ON THE SEA-SHORES
oF PERU, AUSTRALIA, DEVONSHIRE, CORNWALL, &c.

By Richard Edmonds . - = : : : :
THE Native Copper MINES oF Lake Superior. By
James Douglas ¢ ; : ; - . : °

On THE MODERN HypoTHEsEs oF AToMIc MATTER AND
LuMINIFEROUS ETHER. By Henry Deacon.

EXHIBITION IN MANCHESTER OF APPLIANCES FOR THE
PRODUCTION AND ECONOMICAL USE OF FUEL

AN INVESTIGATION OF THE NUMBER OF CONSTITUENTS,
ELEMENTS, AND MINoRS oF A DETERMINANT. By
Captain Allan Cunningham, R.E., Honorary Fellow of
King’s College, London. : : . 3 :

NOTICES OF SCIENTIFIC WORKS.

St. Clair’s ** Darwinism and Design; or Creation by Evolution ”
Stewart’s ‘‘ The Conservation of Energy” . : : - 5
Ribot’s “* Contemporary English Psychology ” :
Pettigrew’s ‘Animal Locomotion; or Walking, Swimming, and

Flying” . -

Smith’s ‘ Fruits and Petiaaees the Proper faaed of Man 7
Geikie’s ‘ Geology ” : : : : wae ; -

PAGE

I4I

156
162

180

194

212

229
232
236

237
239
249

CONTENTS.

PAGE
Marshall’s ‘‘A Phrenologist Amongst the Todas, or the Study
of a Primitive Tribe in South India; History, Character,
Customs, Religion, Infanticide, Polyandry, Language” . 240
Jordan’s ‘The Ocean; its Tides and Currents, and their Causes” 246
Alleyne Nicholson’s * Outlines of Natural History for Beginners” 248

Winslow’s “Manual of Lunacy” . : : ; - 250
Armstrong's *‘ Introduction to the Study of os Crfemistey® 250
Rodwell’s ‘The Birth of Chemistry” . ; : : 5 » S5e
Miller’s ‘‘ Elements of Chemistry ” : + 252
Davies’s ‘‘ The Preparation and Mounting of icrtcone Objects” 252
Lankester’s ‘‘ Half Hours with the Microscope” . : : - 253
Gosse’s “‘ Evenings at the Microscope, or Researches among the .

Minuter Organs and Forms of Animal Life” . : - 254
Culley’s ‘‘ Handbook of Practical Telegraphy” . : : - 255
Bullock’s ‘‘Student’s Class Book of Animal Physiology ”. - 257
Nelthropp’s ‘ Treatise on Watch-work” : : : 5 - 259

PROGRESS IN SCIENCE.

Including Proceedings of Learned Societies at Home and Abroad, and
Notices of Recent Scientific Literature.

MINING . . . : . . : : : F i - 261
METALLURGY . ° : . : : : : : ° . 263
MINERALOGY . ; : . ‘ ‘ 5 - - ; - 264
ENGINEERING . - 5 : : : : : . : - 266
GEOLOGY . : : ; : ° ° : ° ; : - 271
PHysics . : ; E F : : . : : : - 273

TECHNOLOGY . : F : :. ; < . 280

Segbiteterrsseetrs

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Hiss ican esse

= HSE

The Ouarterly Journal cf Scones No XLT: April ISTE.

THE QUARTERLY

meee NAL OF SCIENCE.

APRIL, 1874.

Peon THE FLINT AND CHERT IMPLEMENTS
FOUND IN KENT’S CAVERN, NEAR
TORQUAY, “DEVONSHIRE.

By inV. -PENGELLY,, FF RiS., » ke:
eS the northern shore of the beautiful inlet of the
We

English Channel known as Torbay, in Devonshire,

stand the town and harbour of Torquay; and about
a mile eastward from the harbour there is a small hill,. con-
sisting exclusively of limestone, and containing the cele-
brated Kent’s Hole or Cavern. It is but little more than
200 feet above mean tide, whilst immediately on the south-
west, and about half a mile to the north-west, rise two
loftier eminences, known as Lincombe and Warberry Hills,
consisting of grey shales and dark red grits, and reaching the
heights of 372 and 450 feet respectively.

Though the cavern seems to have been well known at
least three centuries ago, the attention of palzontologists
and anthropologists was first directed to it by the labours
and discoveries of the late Rev. J]. MacEnery, of Torquay.
In his ‘Cavern Researches,” he says :—‘‘ In the summer of
1825, Dr. Buckland, accompanied by Mr. Northmore, of
Cleve, visited the cave of Kent’s Hole in search of bones. I
attended them. Nothing remarkable was discovered that
day, excepting the tooth of a rhinoceros and a flint blade.
This was the first instance of the occurrence of British
relics being noticed in this, or, I believe, in any other cave.
Both these relics ’twas my good fortune to find.’’*

Towards the close of the same year, he commenced a
somewhat systematic exploration of the Cavern, and, in the
course of his researches, met with a considerable number of
flint implements; and, believing the ground in which they
were met with to have been previously broken up, he set
himself seriously to work to ascertain whether or not they
occurred under the undisturbed floor of stalagmite, covering

* Trans. Devon. Assoc. for the Advancement of Science, Literature, and
Art, vol. iii., p. 441. 1869.
VOL. V. (N.S.) T

142 Flint and Chert Implements (April,

the loam or muddy deposit now known as Cave-earth. His
description of this work is so graphic, displaying at once his
mode of operation and his mental excitement, that I cannot
refrain from quoting it :—

‘‘ Having cleared away on all sides the loose mould and
all suspicious appearances, I dug under the regular [stalag-
mitic] crust, and flints presented themselves to my hand.
This electrified me. I called the attention of my fellow-
labourer... and in his presence extracted from the red marl
arrow and lance-heads. I instantly proceeded to the ex-
cavation inside, which was only a few feet distant in the same
continuous line, and formed part of the same plate—the crust
is about two feet thick, steady (7.c., of uniform thickness); the
clay rathera light red. About three inches below the crust, the
tooth of an ox met my eye: I called the people to witness the
fact, ... and not knowing the chance of finding flints, I then
proceeded to dig under it, and at about a foot I dug out a flint
arrow-head. This confirmation—I confess it—startled me. I
dug again, and behold, asecond! of the same size and colour
(black). I struck my hammer into the earth a third time,anda
third arrow-head, but white, answered to the blow. This was
evidence beyond all question. I then desisted, not wishing
to exhaust the bed, but, in case of cavil, leaving others an
opportunity of verifying my statements by actual obser-
vation.’’*

The following is the substance of his further remarks on
the subje¢t:—The implements lay ordinarily between the
bottom of the stalagmite and the upper surface of the cave-
earth, but were occasionally, though rarely, buried a few
inches deep in the latter, and mixed with the bones of the
extinét cave mammals. None occurred in the stalagmite
itself. Some were broken, and, as in the case of bones in a
similar condition, the separated parts were found at some
distance from each other. Instances were met with of
indurated or coherent masses made up of Cave-earth, stones,
fossil bones, and flint tools. In common with most observers
of that time, he ascribed the introduction of the Cave-earth
to the Deluge, and though, under the influence of Dr. Buck-
Jand, he finally expressed the belief that the implements
were “ post-diluvial,” he contended that the facts just enume-
rated seemed ‘“‘to countenance the opposite hypothesis ;”
though he was staggered by the belief that there were no
implements in the cave-earth at depths exceeding a few
inches, and no remains of the extinét mammals in the

* Trans. Devon. Assoc., vol. iii., pp. 329-30.

1874.] in Kent’s-Cavern. - 143

stalagmitic floor. His conviction was decided and firm that
before the commencement of the formation of the stalagmite
the tools occupied the place in which he discovered them ;
and when he found Dr. Buckland inclined to attribute them
toa more modern date by supposing that the ancient Britons
had scooped out ovens in the stalagmite, and that they had
thus got admission to the cave-earth, he replied—‘‘ Without
stopping to dwell on the difficulty of ripping up a solid floor,
which, notwithstanding the advantage of undermining and
the exposure of its edges, still defies all our efforts, though
commanding the apparatus of the quarry, I am bold to say
that in no instance have I discovered evidence of breaches
or ovens in the floor, but one continuous plate of stalagmite
diffused uniformly over the loam.” ‘‘It is painful,” he
adds, ‘‘ to dissent from so high authority, and more particu-
larly so from my concurrence generally in his views of the
phenomena of these caves, which three years’ personal
observation has in almost every instance enabled me to
verity.”’*

Mr. Godwin-Austen, who, familiar with MacEnery’s
discoveries, had supplemented them with independent
researches of his own, writes thus, in 1840:—‘ Arrow-
heads and knives of flint occur in all parts of the
cave, and throughout the entire thickness of the clay ; and
no distinction founded on distribution or relative position
can be observed whereby the human can be separated from
the other veliquie.”t It is noteworthy, perhaps, that this
important statement entirely removed the chief difficulty
which MacEnery felt, in view of the hypothesis that man
was, in Devonshire, contemporary with the extinct cave
mammals. He believed that the flint tools did not occur at
_ depths of more than a few inches in the cave-earth. It was
reserved for Godwin-Austen to discover that, like the fossil
bones, they were to be met with at all depths.

In 1846, a committee appointed by the Torquay Natural
History Society carried on some very limited but most
careful explorations in the Cavern; and make the follow-
ing statement in their report, drawn up by Mr. E. Vivian,
and read, the following year, to the Geological Society of
London and the British Association :—“‘ After taking every
precaution, by sweeping the surface and examining most
minutely whether there were any traces of the floor having
been previously disturbed, we broke through the solid

* Trans. Devon. Assoc., vol. iii., pp. 334 and 338.
+ Trans. Geol. Soc. of London, (2nd series), vol. vi., p. 444. 1842.

144 Flint and Chert Implements (April,

stalagmite in three different parts of the cavern, and in
each instance found flint knives. ...In the spot where the
most highly finished specimen was found, the passage was
so low that it was extremely difficult, with quarrymen’s
tools and good workmen, to break through the crust; and
the supposition that it had been previously disturbed is im-
possible.’’*

Notwithstanding these repeated and concurrent announce-
ments by independent and competent explorers, even the
scientific world remained perfectly apathetic or altogether
sceptical.: Nor were they more influenced by the researches,
with similar results, carried on in the caverns near Liége,
by Dr. Schmerling, in 1833-34, or those of M. Boucher de
Perthes in the river gravels of the Somme, a few years
later. This strange apathy appears to have been based
partly on the impression that the work had not been
executed with sufficient care, and partly on the feeling that
the belief respecting the date of the first appearance of man
on the earth which held possession of almost every mind
neither could nor should be disturbed.

Be this as it may, such was the attitude of most men of
science up to 1858, when some quarrymen, in the ordinary
course of their work, broke unexpectedly into a virgin
cavern on Windmill Hill, Brixham, on the southern shore
of Torbay. I almost immediately visited it, prevailed on
the proprietor to discontinue the desultory excavations
which he had begun, and secured from him the refusal of a
lease in the cavern, in the hope that arrangements might be
made for making a thorough and systematic exploration.
It was soon after visited by the late Dr. Falconer, who,
believing it might be capable of throwing light on certain
paleontological problems then awaiting solution, prevailed
on the Royal and Geological Societies of London to under-
take the work. It was entrusted to a committee of the
latter body, who placed it under my immediate super-
intendence as the only member residing in the district. The
investigation was begun in July, 1858, and in the following
September I was able to announce to the British Association,
at Leeds, that in the new cavern flint implements had been
found under an unbroken floor of stalagmite, deep in the
cave-earth, and mingled with the remains of the ordinary
extinét cave mammals. It was at once felt that the method
and care which had been observed in the work rendered it
impossible to doubt or to ignore the facts, or to resist the

* Report Brit. Assoc., 1847. Proceedings of the Sections, p. 73.

1874.] in Kent's Cavern. 145

conviction that man had, in Britain, been the contemporary
of animals which had become extinct, and that his first
appearance was of higher antiquity than had generally been
supposed.

In the autumn of 1858, the exploration at Brixham being
still in progress, Dr. Falconer, having visited M. Boucher de
Perthes, urged Mr. Prestwich to proceed to the valley of the
Somme, and make a careful examination of the sections for
himself. This was accordingly complied with, and the
latter geologist, by embodying the results of his observa-
tions in a paper read to the Royal Society in May, 1859,
may be said to have completed the revolution. Sir Charles
Lyell, when opening the Geological Section of the British
Association at Aberdeen, in September of the same year, not
only announced his adhesion to the new opinion, but became
one of its most powerful advocates; and so great and
widely spread was the interest felt in the question that
when, in 1863, he published his ‘‘ Geological Evidences of
the Antiquity of Man,” he had the pleasure of placing the
third edition of his work in the hands of the public before
the end of the year.

It being felt to be on many accounts desirable to make a
systematic exploration of the large branches of Kent’s
Cavern still remaining intact, the British Association, when
assembled at Bath, in 1864, appointed a large committee to
carry on the work, and placed at their disposal a consider-
able grant of money for the purpose. ‘The investigation,
under the immediate superintendence of Mr. Vivian and
myself—the only two resident members of the committee—
was commenced on 28th March, 1865; it has been con-
tinued to the present time, and is still in progress. Nine
annual reports have been sent in to the Association and
ordered to be printed, and ample grants of money have been
voted every year.

It is my object in the present paper to state what stone
implements have been discovered in the cavern, and to call
attention to the fact that whilst all the noteworthy speci-
mens are unpolished, and found with the remains of extin&
mammals, they belong to two distinét classes, eras, and
stages of civilisation.

Though there are said to be persons capable of believing
that the so-called stone implements found in Kent’s Hole
and other caverns, as well as in the river-gravels, are merely
natural products, it is not my intention to say one word on
that question. It has been treated so fully and so ably by
various writers as to deprive me of any pretence for attempting

146 Flint and Chert Implements (April,

to add anything to the literature of the subject, and also
of any hope that such additions as I might be able to
make would have the least effect on those still remaining in
a sceptical state.

It may be as well at the outset to describe the successive
deposits, and their principal contents, met with in the
cavern during the exploration now in progress. They are
as follow, in descending order :—

Ist, or uppermost. Blocks of limestone, from a few pounds
to upwards of 100 tons each, which had fallen from the roof
from time to time, and were in some instances cemented
together with carbonate of lime.

and. Beneath and between the blocks just mentioned lay
a dark-coloured mud, consisting largely of decayed leaves
and other vegetable matter, from 3 to 12 inches thick,
and known as the Black Mould.

3rd. Under this was a stalagmitic floor, commonly of
granular texture, varying from an inch or even less to
upwards of 5 feet in thickness, frequently containing
large blocks of limestone, and termed the Gvranular
Stalagmite.

4th. An almost black layer, about 4 inches thick, com-
posed mainly of small fragments of charred wood, and dis-
tinguished as the Black Band, occupied an area of about
100 square feet, immediately under the granular stalagmite,
and, where nearest to it, about 32 feet from one of the
entrances to the cavern. Nothing resembling it was found
elsewhere.

5th. Immediately under the Granular Stalagmite and the
Black Band, lay an accumulation of light red clay, con-
taining on the average about 50 per cent of small angular
fragments of limestone, and somewhat numerous blocks of
the same materials as-large as those already mentioned as
lying on the Black Mould. In this deposit, known as the
Cave-earth, many of the stones and osseous remains were, at
all depths, invested with thin stalagmitic films; and it
occasionally contained large isolated masses of stalagmite
having a very crystalline texture, sub-angular and rounded
fragments of quartz and dark red grit sometimes cemented
into more or less round detached lumps of firm concrete,
and a very few granitoid pebbles. The Cave-earth was
usually of unknown depth, certainly and perhaps greatly .
exceeding 4 feet, but it was occasionally much less, and
in some instances there was none.

6th. Wherever the bottom of the Cave-earth was reached,
there was found beneath it a floor of stalagmite having a

1874.] in Kent's Cavern. 147

crystalline texture, identical with that of the isolated masses
just mentioned as being incorporated in the Cave-earth.
This, designated the Crystalline Stalagmite, was usually of
greater thickness than the upper or granular floor, in the
same branch of the Cavern, and was in some instances but
little short of 12 feet. Where there was no Cave-earth, the
two stalagmites lay one immediately on the other.

yth. Below the whole occurred, so far as is at present
known, the lowest and oldest of the deposits which the
Cavern now contains. It was composed of sub-angular and
rounded pieces of quartz and dark red grit, the latter being
the more prevalent, embedded in a sandy paste of the same
colour. Small angular fragments of limestone, and thin
investing films of stalagmite, both prevalent in the Cave-
earth as already stated, were extremely rare; large blocks
of limestone were occasionally met with, and the deposit, to
which the name of Breccia has been given, was of a depth
exceeding that to which the exploration has yet been carried.

The masses of Crystalline Stalagmite and the fragments
and lumps of dark red grit found embedded in the Cave-
earth are undoubtedly portions, not 7 sztu, of the two older
deposits—the Crystalline Stalagmitic floor and the Breccia—
and show that these accumulations had been broken up by
some natural agency at least partially before the introduc-
tion of the Cave-earth into the Cavern, and that they were
formerly of greater volume than at present.

Excepting the overlying blocks of limestone (No. 1), which
need not be mentioned again, all the deposits contained
remains of animals. In the Black Mould, the most modern
accumulation, they were those of species still existing, and
almost all of them now occupying the district. They were
man, dog, fox, badger, brown bear, Bos longifrons, roe-deer,
sheep, goat, pig, hare, rabbit, water-rat, and seal.

In the Granular Stalagmite, Black Band, and Cave-earth,
extinct as well as recent species presented themselves. The
cave-hyzena was the most prevalent, but was followed very
closely by the horse and rhinoceros. Remains of the
so-called Irish elk, wild-bull, bison, red-deer, mammoth,
badger, the cave, grizzly, and brown bears, were by no
means rare; those of the cave-lion, wolf, fox, and rein-
deer were less numerous; and those of beaver, glutton, and
Machairodus latidens were very scarce. ‘The presence of the
hyzena was also announced by his coprolites, by bones
broken after a manner still followed by existing members of
the same genus, and by the marks of his teeth found ona
very large proportion of the osseous remains.

148 Flint and Chert Implements [April,

In the lowest deposits—the Crystalline Stalagmite and the
Breccia—remains of animals were less uniformly distributed.
In some instances there were none throughout considerable
volumes of the deposits, whilst in others they were so
numerous as to form 50 per cent of the entire deposit. To
use the language of one of the workmen employed in the
exploration, ‘‘they lay about as thick as if they had been
thrown there with a shovel.” So far as is at present known,
they were exclusively the remains of bears. Not only were
there no bones of the hyzena, there were none of his feces,
none of his teeth-marks, no bones fractured according to his
well-known pattern,—nothing whatever to indicate his
existence.

The bones found in the uppermost deposit—the Black
Mould—were of much less specific gravity than those in the
accumulation below it, and were generally so light as to
float in water. Those in the two sets of deposits repre-
sented by the Cave-earth and the Breccia respectively, had
lost their animal matter, and adhered to the tongue when
applied to it so as frequently to support their own weight ;
but those from the Breccia and its Stalagmite—the lowest
deposits—were distinguished from those of the Cave-earth
series in being much more mineralised, more brittle, and by
frequently emitting a metallic sound when struck.

The following general statements may be of service, by
way of recapitulation, before proceeding further :—

Ist. The Cavern contained three distinét mechanical
accumulations—the Black Mould, or uppermost, or most
modern; the Cave-earth, including the local Black Band ;
and the Breccia, or lowermost, or most ancient. Their
mode of succession was never transgressed, and the materials
of which they consisted were so very dissimilar as to charac-
terise them with great distinctness.

and. These three accumulations were separated by two
distinct floors of stalagmite having strongly contrasted cha-
racters. That dividing the Black Mould, or uppermost
deposit, from the Cave-earth was granular; whilst that lying
between the Cave-earth and Breccia, or lowermost deposit,
was eminently crystalline.

3rd. Animal remains occurred everywhere, but were
much more abundant in the mechanical deposits than in the
stalagmites.

4th. The period represented by the Black Mould—the
most modern period—may, as a matter of convenience, and
so far as the Cavern is concerned, be termed the Ovine period,
remains of sheep being restricted to this accumulation.

1874.] in Kent’s Cavern. 149

5th. The period of the Granular Stalagmite, Black Band,
and Cave-earth may be denominated the Hyenine period, the
remains of hyzna being confined to these deposits, and
more prevalent there than those of any other species.

6th. The period of the Crystalline Stalagmite and Breccia
—the most ancient period represented by the Cavern deposits
so far as they are at present known—may be called the
Ursine period, these deposits having yielded remains of bear
only. It must be understood, however, that bears are repre-
sented in all the deposits.

“7th. The bones of each period were distinguishable by
their condition; those from the Black Mould being lighter,
and those found in the Breccia being more mineralised, than
the products of the Cave-earth.

Flint and chert implements presented themselves in each
of the mechanical deposits, and, as in the case of the bones,
those belonging to any one of them were easily distinguish-
able from those of the other two.

The implements of the Black Mould—the Ovine, or most
modern period—were of the ordinary colour of common
flints. ‘They were mere flakes and ‘‘strike-lights,” the latter
probably used and cast aside or lost by those who, during a
long period, and before the invention of lucifer-matches,
acted as guides to the Cavern. All further mention of them
may be omitted as not being noteworthy.

Omitting mere flakes and chips, of which there were
great numbers, the principal implements found in the Cave-
earth—the Hyzenine period—were ovoid, lanceolate, and
tongue-shaped, produced by fashioning, not flint or chert
nodules, but flakes struck off them for the purpose. They
were of comparatively delicate proportions; those of flint
were usually of a white colour and porcellanous aspect, and
having, through metamorphosis, a granular chalk-like texture.

mhese are “not the only human industrial remains found
in the Cave-earth, as it has yielded a bone needle or bodkin
with a well-formed eye, three bone harpoons or fish spears—
one of them barbed on both sides, and the others on one
only—a bone pin, a bone awl, hammer stones, ‘ whetstones,”
charred bones and wood, and a badger’s canine tooth having
its fang artificially perforated apparently for the purpose of
being strung with other objects to form a necklace or
bracelet—an indication that the cave men of the Hyznine
period occupied themselves in making ornaments as well as
objects of mere utility.

The implements from the Breccia—the Ursine, or most
ancient of the periods—were much more rudely formed,

VOL. V. (N.S.) U

150 Flint and Chert Implements (April,

more massive, less symmetrical in outline, and made by
operating, not on flakes, but directly on nodules, which
appear to have been derived from supracretaceous gravels
between Torquay and Newton Abbot, about four miles from
the Cavern, and generally retain portions of the original
surface. It is obvious, however, that even such tools could
not be made without the dislodgement of flakes or chips
from the nodule, and, accordingly, remnants of this kind
have presented themselves in the Breccia, but they are all ofa
very rude character. There was also a mass of flint which
may have been a ‘‘core” from which flakes had been
struck, or, what seems not less probable, the useless result
of an abortive attempt to make a tool.

No such implements have been found in the Cave-earth,
nor have any of the comparatively slender, symmetrical
tools of this less ancient deposit been found in the Breccia.
They are by no means so abundant as those of the Cave-
earth; that is to say a given volume of Breccia has not
yielded so many implements as would on the average occur
in an equal volume of the more modern accumulation.
Whether equal periods of time are represented by equal
volumes of deposit in the two cases, or whether equal
periods of time represent equal numbers of human cave
dwellers or tool-makers in the two eras, are questions which
present themselves, but into which it is not possible to go
fully at present. Omitting rude flakes and chips as well as
the “‘ core” or “ failure” just mentioned, the Breccia has up
to this time yielded no more than eleven specimens of the
kind. It must be remembered, however, that the time
during which the explorers have been excavating the Brecciais
comparatively short. The implements just mentioned are
the only indications of man which have been found belonging
to the Ursine period.

That the implements from the Breccia belonged to an
earlier period than those from the Cave-earth is obvious from
the position they occupied; they were lodged in a deposit
which, when the two were found in the same vertical section,
invariably underlay the Cave-earth. In fact, every tool
found in the Breccia actually had Cave-earth above it.

That the two periods were separated by a great chrono-
logical interval is indicated by the geological and palezonto-
logical facts, and the considerations growing out of them :—

1st. The Breccia and the Cave-earth, though deposited on
the same area, were very dissimilar, as has been stated; the
former consisting of a dark red sandy paste containing a very
large number of sub-angular and rounded fragments of dark

1874.] wn Kent's Cavern. I51I

red grit, which, though derivable from the adjacent and
loftier eminences, the Cavern-hill could not supply ; and the
latter, or more modern, being made up of a light red clay
with small angular fragments of limestone.

and. ‘These two deposits were separated by a sheet of
Crystalline Stalagmite, in some places almost 12 feet thick,
formed after the materials of the Breccia had all been
introduced, but before the introduction of the Cave-earth
commenced.

3rd. After the Stalagmite just mentioned had sealed up
the Breccia, it was in extensive parts of the Cavern, broken
up by some natural agency, and much of the underlying
Breccia was dislodged and carried out of the Cavern, before
the first instalment of Cave-earth was deposited.

4th. The Cavern faunz during the two periods were very
dissimilar: that of the Breccia did not include the hyena,
which played so conspicuous a part in the Cavern history
during the subsequent Cave-earth era, and whose agency,
next to that of man, made cavern searching an important
branch of science. When his cavern-haunting habits are
remembered, it will be seen that his absence in the one
fauna, and his presence in the other, render it eminently
probable that he was not an occupant of Britain during the
earlier period.

The same inference cannot with an equal approach to
certainty be drawn respecting the horse, ox, deer, &c.,
though the absence of their remains from the Breccia is
equally pronounced ; for it may be presumed that their bones
occur in caverns simply because their dead bodies were
dragged there piecemeal by the hyzena, and this could not
have occurred, even though they had crowded the country,
before the arrival of the great bone-eating scavenger who
made the Cavern his home.

The remains of the bear in the Breccia present no
difficulty, for their introduction did not require the agency
of the hyzena, since the bear is a cave-dweller. Dr. Leith
Adams, F.R.S., so well known as a naturalist and cavern
explorer, writing me on the subject, says:—‘‘ The Brown
Bear of the western Himalayas hybernates, choosing chiefly
caverns and rock crevices, which it abandons in spring to
wander about; but old individuals, when no longer equal to
the same amount of exertion, take to a secluded life, and
usually select a cavern on a rocky mountain side, at the base
of which there is abundant verdure and shade, with a pool
or spring where they bathe frequently, or recline during the
heat of the day to escape the annoyance of insects. Such

152 Flint and Chert Implements (April,

retreats are easily discovered by the animals’ footprints on
the soil and turf. They are seen like steps of stairs leading
from the pool in the direction of the den, being brought
about by the individual always treading in the same track.
Thus the patriarch or hermit bears spend their latter years
in one situation, pursuing the even tenor of their ways to
the little stream or pond below, and grassy slopes, to feed on
the rank vegetation, returning regularly to the caverns,
where they end their days.”

5th. The deposits just described are obviously not only
distinct, successive, and protracted terms in the Cavern
chronology, but indicators of changes in the conditions of
the geographical features of the immediately surrounding
country, and of the relation of the Cavern to it. During the
period of the Breccia there was a machinery capable of
transporting from Lincombe hill, or Warberry hill, or both,
or from some greater distance, fragments of dark red grit,
varying in size from pieces four inches in mean diameter to
mere sand, and lodging them in the Cavern. This so
completely passed away that nothing was carried in; but
the deposit, already there, was covered with a thick sheet
of Crystalline Stalagmite obtained through the solution
of portions of the limestone in the heart of which the
Cavern lay. ‘This also ended: the stalagmite was broken
up by some natural agency, apparently not by one effort, but
by many in succession, and much of the Breccia was
dislodged and carried out of the Cavern. This having in
like manner come to a close, again a deposit was introduced ;
but, instead of being dark red stones and sand, as in the
former instance, it was a light red clay; and in it were
embedded small fragments of limestone, which, from their
angularity, could not have been rolled, but were in all
probability supplied by the waste of the walls and roof of
the Cavern itself. It contained also the bones of numerous
species of mammals, and of these the remains of the hyzena
were the most prevalent.

Nor is the paleontology of the two periods less significant
of physical charges. If the absence of any traces of the
hyzena from the older deposit has been corre¢tly interpreted
above, as signifying that the species was not then an
occupant of Britain, it follows thatit was subsequently possible
for him to arrive here, or, in other words, Britain had
become connected by dry land with the Continent. In short,
the facts point to the conclusion that the earliest Devonshire
men known to us—the men of the Ursine, the Breccia
period—saw this country an island as we see it, and that in

1874.] in Kent's Cavern. 153

the time of their descendants, or their successors, prior to
the Hyzenine or Cave-earth era, it had reached a continental
condition. This latter condition has so long ceased that
the earliest traditions respecting our land recognise it as an
island, even though they profess to go back to a time when
Anglesea was not yet detached from Wales.*

Readers of Sir C. Lyell’s ‘‘ Antiquity of Man” are aware
that he recognises two distinct periods in geologically recent
times when Britain was in a continental condition. He
supposes that the well-known ‘‘forest of Cromer,” in Norfolk,
in which Scotch and spruce first were prevalent, flourished
at the close of the first of them; that in the intervening
period, the land north of the Thames and Bristol Channel
was gradually submerged until a few mountain tops alone
remained above the sea; and, from the evidence then
available, that the first appearance of man when -
he ranged from all parts of the Continent into the British
area, took place during the second continental period.” ft

If, however, the new evidence from Kent’s Cavern has
been correctly interpreted above, the first appearance of
Man in Britain was prior to the second continental period,
and must have been at least as early as the previous insular
era. Indeed, unless we suppose him to have possessed the
means of navigation, it must have been in the first
continental period.

It is worthy of remark that the hypothesis that the land
south of the Thames and Bristol Channel was not submerged
during the interval separating the two continental periods,
harmonises well with the supposition that Devonshire was
occupied by man during that interval.

Without at present attempting to pursue further the
question of the relation of the oldest Devonshire men yet
known to Glacial times, I cannot divest myself of the belief
that the complete exploration of Kent’s Cavern will furnish
a definite reply to it.

Though no one acquainted with the present state of
the evidence would attempt to express in years, or other
astronomical units, the amount of time represented by the de-
posits of the Ovine and Hyznine periods, it cannot be doubted
that the spindle whorls, the pottery, the bone combs, and
the fibule of the Black Mould—the first or uppermost of
these—go back to Romano-British and Pre-Roman times, to
at least two thousand years from the present day as a
Minimum. All thatisknown about the Granular Stalagmite—

* See the 67th of the Historical Triads of Britain.
+ Antiquity of Man, pp. 282-3.

154 Flint and Chert Implements (April,

the preceding term of the series—points to the conclusion
that it was formed slowly. That the main lines of
drainage through the roof have remained unaltered is seen
in the facts. that those parts of the cavern which have an
unusually thick floor of stalagmite have also, at present,
more than an ordinarily copious drip; where the floor is but
thin the drip is never of great amount; and where there is
no floor—for a few such places occur—the cavern is quite dry
at allseasons; and further, wherever a conspicuous stalactite
depended from the roof, there was found, vertically below,
rising from the Granular Stalagmitic floor a considerable boss
of the same material to meet it ; and whenever the lower or
Crystalline Stalagmitic floor was found in such a se¢tion, a
similar but larger boss existed on it also. In_ several
parts of the Cavern there are names, initials, and dates
inscribed on the Granular Stalagmite, where it is certainly of
great thickness, and where additions are still being made to
it. There is satisfactory evidence of their genuineness; and,
though some of them are upwards of two hundred and fifty
years old, and are slightly glazed over, they are perfectly
legible, and the film accreted on them cannot be more than
the twentieth of an inch in thickness. It is not pretended,
of course, that this rate must be taken as a trustworthy
chronometer for the entire thickness, but those who object
to it must expect to be called on to state why they do so;
and even if the objection should be sustained, it will be
seen that, when a thickness of five feet presents itself for
measurement—a rate even ten times as great as that which
has certainly obtained for more than two and a half
centuries—betokens a great antiquity.

That the Cave-earth, every portion of which is necessarily
older than the most ancient part of the stalagmite covering
it, was accumulated very slowly is seen in the great number
of small angular fragments with which the walls of the
cavern have crowded it, and in the films of stalagmite
which, as already stated, invest the bones and stones every-
where throughout the total depth of the mass, since each
such film indicates that the spot the invested objet occupies
was a portion of the floor of the Cavern during a time sufficient
for its accretion, and that it was only prevented from growing
into a thick wide-spread sheet by the introduction and lodge-
ment on it of a small instalment of Cave-earth.

Whatever be the aggregate amount of time represented by
the less ancient deposits just spoken of, there can be little
doubt that at least fully as much is absorbed by the more
ancient cavern history, of which the formation of the
Breccia and Crystalline Stalagmite, as well as the subsequent

1874. in Kent’s Cavern. rae

destruction and dislodgement of great portions of these, are
the exponents. It may be true that the Breccia was
introduced at a more rapid rate than the Cave-earth ; and,
indeed, this is rendered not improbable by the great paucity
of angular fragments of limestone, as well as of films of
Stalagmite in the older deposit ; but this is probably more
than neutralised by the immense thickness of the Crystalline
or older Stalagmite as compared with that of the Granular or
more modern; the former being in one chamber but little
short of 12 feet, whilst the latter has in no instance much
exceeded 5 feet.

In short, and speaking for myself, however far back in
antiquity the fabricators of the Cave-earth tools take their,
stand, I cannot hesitate to place those of the implements of
the Breccia as much further back. Many must remember,
and perhaps few were surprised at, the alarm occasioned by
the antiquity of man disclosed by the researches in Brixham
Cavern, in 1858; and now, cavern researches, growing out of
those just mentioned, appear to me to make an irresistible
demand to have human antiquity in Britain at least doubled.

Up to the present time, as the Cavern has disclosed more
and more ancient men, it has shown that they were ruder
and ruder as they withdrew into antiquity. The men of the
Black Mould had a great variety of bone implements, they
used spindle whorls, and made pottery, and smelted and
compounded metals. The older men of the Cave-earth
made a few bone tools, they used needles, and probably
stitched skins together, and even perforated badgers’ teeth
to enable them to be strung as necklaces or bracelets, but
they had neither spindle whorls nor pottery, nor metals of
any kind; their most powerful weapons were made of flakes
of flint and chert, many of them symmetrically formed and
carefully chipped, but it seems never to have occurred to
them to increase their efficiency by polishing them. The
still more ancient men of the Breccia have left behind them
not even a single bone tool; they made implements of
nodules, not flakes, of flint and chert; tools that were rude and
massive, had but little regularity of outline, and were but
roughly chipped.

It has not been unusual to hear the men of the Cave-
earth period spoken of as Primeval Men, or Aborigines of
Devonshire ; the discovery of men of higher antiquity in the
Same area is at once a proof that the names are inappro-
priate, and a warning against applying them to even the men
of the Breccia; for, though these are no doubt the oldest
men yet known to us, they hint that further discoveries may
yet be made.

( 156 )

II. ON RECENT EXTRAORDINARY OSCILLA-
TIONS OF THE WATERS IN LAKE ONTARIO
AND ON THE

SEA-SHORES OF PERU, AUSTRALIA,
DEVONSHIRE, CORNWALL, &c.

By RicHARD EDMONDs.

Yk HESE tide-like alternating currents, which resemble in
all respects those observed on the shores of this and
other countries on the days of the two great earth-

quakes of 1755 and 1761, commence generally, if not always,

with an efflux, and occupy from five to ten minutes in ebbing,
and about the same time in flowing, the ebb and flow and
the imperceptible interval between them never exceeding
twenty minutes. Those on the 5th of July, 1843, were
observed between the hours of If a.m. and 5 p.m. in

Plymouth, Falmouth, Mountsbay, the Scilly Isles, Bristol,

and on the eastern coast of Scotland at North Berwick and

Arbroath. ‘Those of the 29th of September, 1869, occurred

on the northern as well as on the southern coasts of Devon-

shire and Cornwall, and at the Scilly Isles. Of these and
all the intermediate ones of importance in these two counties

I have written full descriptions, including all meteorological

particulars.*

These currents, when running in and out of piers or
narrow channels, often drive vessels from their moorings,
and dash them against one another. But when they are
moving up and down a wide open beach, the motion is so
quiet and tide-like that they would not be perceived unless
they were watched for some time. This was amusingly
exemplified at Penzance, when, during such an oscillation,
some children who had been long enough on the beach to
discover it made a play of their discovery, by inducing other
children who had not observed it to go out on some rocks
left dry by an efflux, where they were soon surrounded, and
for many minutes in a great fright lest they should be
drowned.

Such is the nature of these extraordinary oscillations
after the first efflux, whether on sea-shores or on the shores of
lakes. The first efflux is well illustrated by that in Lake

* See “ Literary Gazette” of June, 1843; The ‘‘ Edinburgh New Philosophical
Journal,” 1845, and following years until it merged into the * Quarterly Journal of
Science ;” and the “Philosophical Magazine”’ for January, 1866, and January,

1869.

1874.] Alternating Currents. 157

@mtario on the 13th of June, 1872, as related in the
“Rochester Democrat ” of the 15th of that month. While
some gentlemen of Rochester were in a boat near the beach,
** where the water is usually 2 feet deep at least, their boat
suddenly grounded, and the waters receding left her on a
sand-bank. The gentlemen got out and strolled away, but
looking back shortly after, they saw to their surprise the
boat dashing about in apparently deep water. Securing the
boat with some difficulty, they found her suddenly aground
again, and as suddenly floated after a short interval.
Becoming now interested in this curious ebb and flow of
the lake, they diligently observed it for about three hours.
The ebb and flow occurred every twenty minutes, that is, for ten
minutes the water would gradually recede, then commence rising,
and continue to rise for about ten minutes. The water rose
2 feet and 3 or 4 inches above the ordinary level, then receded
about the same distance below the usual level, making a variation
_m the height of the water of nearly or quite 44 feet every twenty
minutes.’ The above quotation is from the ‘‘ Croydon
Chronicle” of July 13, 1872, and what I have italicised is
also a quotation from an abbreviated notice in the ‘‘ Times”
of the same date.

There was a similar occurrence in this lake on the 2oth
of September, 1845, when the waters suddenly moved “in
a mass out of the rivers, bays, coves, harbours, &c.,” to
a depth of 2 feet, and then returned to an equal height
above their previous level. This happened on each side of
the lake.*

The explanation of these phenomena, whether in lakes or
on the shores of the sea, I have given in the “‘ Transactions
of the Royal Geological Society of Cornwall” for 1843, and
as it is the only one yet proposed that can reconcile all the
observed facts connected with them, I will now give it more
fully, and with the addition of some recent confirmatory facts.

My hypothesis is that an earthquake shock proceeding
upwards vertically from the interior of the earth reaches the
basin of the lake. Now wherever this basin is horizontal
the shock continues its vertical ascent up through the water
as through a solid body, and with greater velocity than the
most rapid flight of a cannon-ball; but none of the water is
thereby displaced except the surface, which, as will be pre-
sently exemplified, is dashed up vertically and then falls
back into its previous place, no current being produced. If
a ship were on the spot, it would receive the shock, and

* Edinburgh New Phil. Journal for July, 1848, pp. 107-109.
VOL. V. (N.S.) x

158 Alternating Currents. [April,

loose pieces of timber, or anchors lying on the deck, and
even men standing on the deck, as will also presently be
shown, would be jerked up to heights proportioned to the
violence of the shock. Much of the basin of the lake,
however, is not horizontal, but sloping from its shores.
Therefore when the shock which had proceeded vertically
up from the interior of the earth reached the inclined or
sloping sides of the basin, it would not continue to proceed
up through the incumbent water vertically or perpendicularly
to the horizon, but perpendicularly to the inclined plane of
the basin, whereby the surface water dashed off would be
jerked towards the centre of the lake. What I have called
an earthquake-shock is really, however, only a single vibra-
tion of an earthquake-shock; for an earthquake-shock
consists usually of a rapid succession of vibrations, sounding
at sea ‘‘like the letting out of a cable,” and on land ‘‘likea
waggon rushing over a paved road.” By such vibrations,
therefore, from the sloping sides of the basin, even if there
were only five or six in a second, and the shock lasted only
30 seconds, a great heap of water would be raised. The
first vibration would, as I have said, jerk the surface water
towards the centre of the lake, and before this dashed off
surface water had time to flow back to its place, fresh
surfaces would be jerked in the same direction by succeeding
vibrations, so that the successive surfaces, whilst being thus
dashed off, would form a current towards the centre, to
supply which an efflux from the shores would necessarily
follow. This efflux would not cease until the vibrations
ceased, and then the heaped-up waters would immediately
flow back to the shores. The subsequent ebbings and
flowings, like the oscillations of a pendulum, would continue
until the equilibrium were restored.

The extraordinary movements of the waters so often
observed in the American lakes, though not always of the
same description as the two in Lake Ontario above given,
may all, I think, be accounted for by my hypothesis. For
example, if the earthquake shock in the bed of the lake be
very partial, and do not occur on its sloping sides, but only
on shoals near its centre—say two hills, or two parallel
ridges, with sides inclining down into the intermediate
valley—then the waters driven from these opposite sides
would meet over the valley and form a high wave, which
might flow on to the shore and rush up without any previous
efflux beyond that slight and momentary retirement of the
water which always precedes the fall of a wave on the shore.

I have said that a vertical shock proceeding from a

1874.] Alternating Currents. 159

horizontal portion of the basin of a lake occasions no
current, because the surface of the water is thereby jerked
up in jets perpendicular to the horizon, which jets fall back
into the places they had previously occupied. An illustration
of this appears in the following extract from the ‘‘Times ” of
October 18, 1869, describing the effe¢éts of a vertical shock
from a horizontal portion of the bed of the sea, over which
a ship was then passing :—‘‘A correspondent writing from
Valparaiso, on 3rd September, 1869, says, ‘I arrived here on
the 28th ult, in the steam ship “‘ Payta,” from Callao.

We left Arica in the morning of the 24th ult., and at 1.20 p.m.
(the ‘“‘Payta’”’ being two to two anda half miles from the
land, fifty seven miles south of Arica, off Gorda Point, and in
seventy-five fathoms of water), the vessel commenced to
shake in the most awful manner, making it impossible to keep
one’s footing. (In another account in the same day’s paper
by the purser of the ‘‘ Payta,” it is stated that ‘the vibration
threw the passengers to the height of two inches* above the
deck’). This convulsed vibration continued 45 or 50 seconds,
during which time the sea presented the appearance of a
heavy fall of large hailstones, sending up jets of water some
eight or ten inches, and being about the same distance apart.
On arriving at Iquique the same night, we learnt that two
very severe shocks of earthquakes had been felt there about
two o’clock in the day.”” Had this vertical shock off Gorda
Point proceeded from an inclined shore, the jets of water,
instead of being jerked up vertically, and falling back into
their previous places as they did, would have been jerked up
obliquely in a seaward direction, rising so little above the
surface that the separate jets would not be distinguishable,
and the entire surface would have been seen as a vast
current rushing seaward, so long as the vibrations continued ;
and, when they ceased, the heaped up water would return
shoreward to find its level.

We have seen that in Lake Ontario, in 1845, as well as in
1872, the water first retired to a depth of two feet or more,
and then returned to an equal height above its previous
level, just as a harp-string or pendulum, when moved to any
distance from its point of rest, will immediately of itself move
twice such distance in the opposite direction. This applies to
marine as well as to lacustrine disturbances. Luke Howard,
describing those at Plymouth on the 11th of May, 1811,
says: ‘“‘the sea fell instantaneously about four feet, and

* Lyell records an instance of men on board a ship forty leagues west of
Cape St. Vincent being thrown by an earthquake shock ‘a foot and a half
perpendicularly up from the deck.”’

160 Alternating Currents. [April,

immediately rose about eight feet.” Those ‘‘ mountainous”
waves, therefore, which overwhelmed the Peruvian cities of
Iquique and Arica, on the 13th of August, 1868, were
nothing more than might have been anticipated from the
illustration by the harp-string and pendulum. For the
great wave, forty feet high, which completed the destruction
of Iquique (directly after the earthquake shock had laid it
in ruins) was immediately preceded by a retirement of the
sea to the extraordinary depth of four fathoms. It was
by a still higher wave, arising from an apparently still
greater retirement of the sea, that Arica was destroyed,
as appears from the following account given by Mr.
Nugent, H.M. Vice Consul, in the ‘* South American
Missionary Magazine” for October, 1868. ‘In the after-
noon of August 13, 1868, about 5 o’clock, we were visited
with a most tremendous earthquake. I had _ scarcely
time to get my wife and children into the street, when the
whole of the walls of my house fell, or rather were blown
out, as if jerked at us. I started over the trembling ground
forthé hills. . . . A great crywent upto heaven, suchas
few’men have heard, ‘The sea is retiring.” . . I looked
back. . . . Isaw all the vessels in the bay carried out
irresistibly to sea (anchors and chains were as packthread),
probably with aspeed of ten milesan hour. Ina few minutes
the great outward current stopped, stemmed by a mighty rising
wave, I should judge about fifty feet high, which came on with
an awful rush, bringing in the whole of the shipping with it,
sometimes turning in circles as if striving to elude their
PARES oo tst The wave passed on, struck the mole into
atoms, swallowed up the Custom-House, . . . carried
everything before it. Ina few minutes all was completed—
every vessel was either ashore or bottom upwards.” ‘‘ The
mighty rising wave” here described was evidently the
accumulation produced by “‘ the great outward current,” and
that outward current was caused by “ the trembling ground”
beneath the sea, that is by the rapid vibrations of the

inclined bed of the sea descending from the shore; for as ~

the dry land was then “ ivembling” or vibrating by the
vertical shock, the adjoining submarine ground must have
been so also. This is a fair specimen (aithough on a terribly
large scale) of all those extraordinary agitations now under
consideration.

Mr. Mallet, however, entertains the idea proposed by
Michell a century ago, that these extraordinary influxes
proceed from the offing, and from vast but very low waves
formed by submarine earthquakes or volcanos at the distance

"ead

1874.] Alternating Currents. 161

sometimes of thousands of miles,* instead of their being
merely the reaction, the rebounds or refluxes of the imme-
diately preceding effluxes occasioned, as I have shown, by local
submarine earth-shocks. And writers in some of our leading
periodicalst, having adopted the same idea, have ascribed
the extraordinary disturbances of the Sea in California, New
Zealand, Australia, and other islands in the Pacific, on the
13th and 14th of August, 1868, immediately after the
destruction of Arica, to one of these great sea waves
produced by a submarine earthquake near Peru, and moving
onwards in all directions with varying velocity (like other
great sea waves) according to the square roots of the
varying depths which they traversed. But such waves are
only imaginary; they have never been seen, nor can their
existence be proved. None such existed at any of the
similar agitations in the West of England which I have
described during the last thirty years; and, therefore, none
such can be rightly assumed to have existed at any other
similar agitations. To remove all doubt, however, on this
point, I invite attention to what was observed at Plymouth,
on the 29th of September, 1869, during the extraordinary
disturbances of the sea that day, on the northern as well as
on the southern coasts of Devonshire and Cornwall. Ex
uno disce omnes.

The alternating current in Cattewater, an anchorage
outside Plymouth pier (Sutton Pool), rushed in and out of
the pier every 15 or 20 minutes, whirling about the boats
and vessels, parting their hawsers, and carrying a schooner
which had almost reached the pier back two or three furlongs,
and then to and fro so helplessly that a steam tug was
despatched to her assistance, and towed her in. This com-
motion was almost universally believed to have come in from
the offing, through the two entrances at the ends of the break-
water. I wassure from past experience that it did not, and so
it proved. One of the keepers of the lighthouse on the break-
water, and one of the labourers there, informed me that they
were on the breakwater all that day, and that the sea there
Was quite undisturbed. Moreover, the foreman of the
labourers, who was absent that day, told me that, after
having witnessed the extraordinary disturbance in Catte-
water, he was so convinced of its having proceeded from
outside the breakwater, that he fully expected, when he

* Quarterly Journal of Science for January, 1864.

+ See the articles on Earthquakes in the “Times” of November 3, 1868, and
the “ British Quarterly Review” for January, 1869, and ‘‘ Blackwood’s Edin-
burgh Magazine” for July, 1869.

162 Copper Mines of Lake Superior. (April,

went thither, to find all his recent unfinished work washed
away. But on arriving at his work the following day, and
finding it precisely as he left it, and hearing from his men
that the sea had been all the time of his absence quite
undisturbed, this unexpected information was to him just as
marvellous as the phenomenon itself in Cattewater.

The only possible cause of the disturbances of the sea
this day, on the northern as well as on the southern coasts
of Devonshire and Cornwall, and at the Scilly Isles, appears
to be local submarine vertical shocks, not rising higher
than the bed of the sea.

These phenomena are never, as I consider, occasioned by
undulatory earthquakes, but only by vertical shocks. During
the earthquake at Antioch, on the 3rd of April, 1872, “‘so
long as the wndulatery motion continued, no houses fell, but
as soon as vertical jerks set in, a large part of the town was
in a few seconds a heap of ruins.”* Providentially these
vertical shocks, proceeding from the deep interior of the
earth, do not generally rise higher than the basins uf lakes,
or the bed of the sea. Thus, on the day of the great
earthquake of 1755, whilst only one shock was perceived on
the surface of the mines in Derbyshire Peak, five smart
ones were felt sixty fathoms undergroundt. On the same
day, not only Lochness and other lakes in Scotland, but
even ponds in England, were violently agitated without any
perceptible shock in their neighbourhoods.

III. THE NATIVE. COPPER MINES’ OF LDARS
SUPERIOR.

By JAMES DouGLas, Quebec.

ae Jesuit fathers who, in extending the domain of

Christianity two centuries ago, explored and described
parts of the American continent, which are still
almost as wild as then, likened Lake Superior to a relaxed
bow on whose string rests an arrow, the north or Canadian
shore being the bow, the south or United States shore the
bow-string, and the arrow the promontory of Keweenah,
which, protruding from the south shore far across the lake,
divides its waters almost into halves. This promontory,

* Times of July 30, 1872.
+ Phil. Trans., 49, p. 398.

1874.] Copper Mines of Lake Superior. 163

while one of the most salient geographical features of the
lake, is moreover geologically and mineralogically the most
remarkable, for on it, running from end to end, exist in their
greatest development those cupriferous beds of trap and
conglomerate in which native copper occurs under con-
ditions most puzzling to the mineralogist, and from which
it is being extracted in quantities sufficient to supply the
growing wants of the United States and to threaten the
stability of the copper market elsewhere.

In the present article, it is not my object to discuss
the cosmical bearing of the subject, but to describe two of
the most noted mines near Portage Lake and the means
adopted to extract the mineral from their ores. Nevertheless,
a sketch of the geology of the region and of the mining
elsewhere in it is necessary as a preface. Lake Superior is
framed in primitive rocks. The gneisses and granites of the
Laurentian formation at places rise in bold cliffs out of the
waters along the east and north shores, and where the shore
line in its trend to the south-west leaves the Laurentides,
the intervening space is occupied by a narrow belt of
Huronian slates and conglomerates, on which seem to rest
unconformably, judging from the scanty evidence afforded
by the survey of this part of the north shore, but con-
formably, according to Brookes and Pompelly,* who have
examined the lines of contact on the south shore, a series of
beds of bluish shale, sandstone, indurated marls and con-
glomerates, interstratified with trap, which is sometimes
amygdaloidal.

Sir William Logan subdivides this great mass of rock,
whose total thickness can be but vaguely guessed at, into
lower and upper groups, and designates them as the upper
copper-bearing rocks of Lake Superior, in distinCtion to the
Huronian or lower copper-bearing series.

The lower group occupies the north-western shore of the
lake, and sweeps round its extreme westerly end, but in the
extension eastward of it and the upper group they are
divided from the south shore by sandstones of a very
different character to those which are interstratified with
their own traps and conglomerates. These sandstones,
which line the south shore, with but few interruptions, from
Sault St. Marie to Duluth, lie in horizontal or very slightly
inclined beds, and, being very friable, have been at several
spots fashioned by the water into the fantastic forms known
as the pictured rocks. Representatives of the same sandstone

* American Journal of Science, June, 1872.

164 Copper Mines of Lake Superior. (April,

occur on some of the islands along the north shore, being
all that remains above water of the soft formation out
of which the bed of the lake was hollowed. But while they
yielded to the destructive agency of water, the harder beds
of the copper-bearing groups have withstood them, and
these, therefore, as on the point of the Keweenah promon-
tory, rise abruptly out of the lake, which has washed away
entirely the sandstone from their flanks, or, as towards the
base of the promontory, spring at as abrupt an angle out of
the horizontal sandstone strata, or else from islands, isolated
or in groups, which, however, always bear a marked rela-
tion to one another and to the lines of upheaval distinguish-
able on the mainland.

The lower group of these rocks which we have described
as confining the western end of the lake has not produced
copper in workable quantities, and differs also in lithological
character from the upper group. On the south side of the
lake this upper group forms distin¢ét ranges, the more
easterly of which are traceable with remarkable parallelism
from the base to the point of the Keweenah promontory ;
and they reappear on the north shore, the more westerly in
Isle Royale, in the Thunder Bay and Neepigon promontories,
and in the St. Ignace group of islands, the more easterly in
Michipicotin and in some of the headlands of the coast.

The age of these rocks is the subject of some difference
of opinion. They seem, from the observation of Brookes
and Pompelly in Northern Michigan, to conform in strike
and dip with the Huronian schists, both uniformly dipping
to the north at angles of 50-—7o°, and where the Huronian
come in contact with the sandstones above mentioned, there
is the same sudden alteration in dip as between these same
sandstones and the copper-bearing rocks on the Keweenah
promontory. Hence, one would infer that the traps and
conglomerates of the upper bearing series come next in age
to the underlying Huronian schists, and that subsequently
to their upheaval were deposited the sandstones whose
horizontality has not been broken by any disturbing force.
The sandstones are generally attributed to the lower
Silurian system.

Copper exploration on the Keweenah promontory have
been made at innumerable spots over a distance of 100 miles
along the strike of the beds, between the Point and Lake
Agogibic, but the mines which have proved productive are
confined to three districts, viz., Keweenah Point or Eagle
River, Portage Lake, and Ontonagon.

On the Point, the copper-bearing rocks attain their

1874.] Copper Mines of Lake Superior. 165 °

greatest lateral.development, and beds of conglomerate,
melephyre, and compact sandstone, with the same dip and
strike, stretch from shore to shore. ‘Thence, as they curve
round in a south-westerly direction, the range diminishes in
width. Some of the first mines opened were on the west
coast of the promontory, where, for nearly 30 miles, members
of the copper-bearing series form the shore wall.

Here the most productive group of mines is on a system
of fissure veins, which cut the rocks of the northern range
at right angles to their strike. The Cliff Mine, the first of
the lake mines to pay a dividend, and which, from first to
last, has distributed nearly 2,280,000 dols. among its share-
holders, is on a vein which, though not generally wide, was
often filled with mass copper. The copper was associated
with quartz, calc spar, and other vein stones. ‘The contents
of the fissure exhibited a banded structure, and was
influenced markedly by the country rock. In this district,
likewise, copper was mined from a bed of amygdaloidal trap,
here known as the ash bed, and work was also done on con-
glomerate beds; but, if we except Copper Falls and the
_ Phenix Mines, the operations on the fissure veins alone have
been financially successful.

While the Cliff Mine near the point of the promontory
was the first to prove that the native copper is more than a
mineralogical curiosity, the Minnesota, near the south-
western end of the range in the Ontanogan district, became
even more famous from the enormous masses of copper it
produced. Here, likewise, the copper occurs in veins which,
though running with the strata, are palpably subsequent
formations consisting chiefly of quartz, calc spar, and
laumonite. The vein stone is different from the enclosing
rock, the walls are well-defined and often grooved. Inthe
Minnesota, the masses were not only large, but frequently
threw off branches into the enclosing rock, which interfered
with their being detached in the usual manner by removing
the country rock adjacent. The prosperity of the mine
ceased after the extraction of a mass of go per cent copper,
weighing 525 tons, in 1857. No mines here are flourishing
at present, nor does there seem to be a like revival of
mining industry to what is taking place in the Keweenah
Point distriét on the ash bed, under the infection of the
successful development of certain beds near Portage Lake.

Portage Lake and River extend so nearly across the
promontory at about 60 miles from its point that a canal
less than three miles long suffices to give water communica-
tion between the east and west shores. The lake is

VOL. V. (N.S.) Y

166 Copper Mines of Lake Superior. (April,

an irregularly-shaped body, as much as two miles wide
where excavated out of the low-lying sandstone, but taper-
ing rapidly where the high, bluff cliffs of the trap beds
of the copper-bearing series confine it. While still in the
low-lying horizontal sandstone, it throws off towards the
north-east a long arm, which expands into Torch Lake,
a considerable body of water whose north-west shore almost
defines the line of conta¢t between the horizontal sandstone
and the steeply-tilted copper-bearing rocks.

As the steamer enters the narrows, and there come into
view the towns of Hancock and Houghton facing one
another on the opposite banks, the large mills on the lake
shore, and the mine buildings and tramways on the heights
above, the contrast between:the modes of activity and the
aims of civilised man, and of the Indians, with whom the
traveller, if he has been long on the lake, must have come
into close contact, strikes the mind very forcibly.

Where the copper-bearing rocks are exposed by the deep
fissures, whose bottom is occupied by Portage Lake, the
width of the range is seven miles, and the beds dip at
an angle of 54° to the North West. They consist of traps of
varying degrees of compactness and shades of colours,
interstratified with conglomerates and sandstones.

According to Macfarlane, ‘“‘ the constituent of the traps of
the Portage Lake District are principally felspar of the
labradorite species, and chlorite of a species allied to
delessite, with which are found occasionally mica, small
quantities of magnetite, and perhaps of augite and horn-
blende.”* He considers the characteristic trap of the region
to consist of :—

Delessite scighivce “sis se: eaeioeee
Labradorite 2%) ais vale eee
PYLOREME 6 Pa ena uae eee ee
Manette «iP Yes apa ea, aus

100°00

The mines in the immediate vicinity of the Lake are on
the amygdaloidal trap. Many have been opened both on
the north and south shores, but those only on the Pewabic
lode—the Quincy, Pewabic, and Franklin mines—have
returned profit to their shareholders. Of these three, the
best worked, and therefore most successful, is and has been
the Quincy, and we shall therefore describe it as being a
typical, though the best example, of its class.

* Geological Survey of Canada, 1866, page 158.

1874.| Copper Mines of Lake Superior. 167

It was opened in 1849, and has been worked uninter-
ruptedly ever since, stemming the tide of low prices when
almost every other mine was carried down the current.

The lowest level is at 1330 feet along the dip of the bed,
and therefore on the incline of the shaft from surface, and
the longest level is 1600 feet. The shafts and all the
workings are opened in productive ground, where that can
be followed ; but as the walls of the copper-bearing bed are
never well defined, and as tracts of rich ground abruptly
alternate with stretches of barren rock, there is found
considerable difficulty in keeping to the lode, as it is called.
Moreover, from being pinched and poor, or even barren, it
will suddenly bulge to 20 or 30 feet of rich rock. The
hanging wall is composed of a fine-grained, compact, bluish
trap, but the characteristic trap beneath is coarse-grained
and amygdaloidal, and approaches in appearance to the
copper-bearing rock.

The copper bed, however, while likewise generally
permeated with small amygdules, is of a deeper red and
breaks with a more uneven fracture. The minerals which
fill the amygdules in the barren bed, viz. quartz, calcspar,
lawmonite, prehnite, not only fill the amygdules here, but
likewise form irregular veinlets rich in copper; and the
chlorite constituents of the rock prevail so largely in parts
as to give it a deep green shade. Pellicles of native copper
enveloped in chlorite often occupy the centre of the
amygdules. We see here the tendency of the copper to
aggregate with the quartz, and the same zeolitic minerals as
-compose the ftssure veins of the Eagle River, and the
bedded veins of the Ontonagon districts; and, therefore, if
we attribute the formation of the one to aqueous agencies,
are led to ask whether the same agencies have not had more
to do with the formation of the beds and their mineral
contents than has generally been attributed to them.

Sheets of native copper occur between the joints of the
trap in the copper bed, and formed evidently through
infiltration, are found also between the trap blocks beyond
the walls of the bed. An indication of subsequent aqueous
action is seen in the streaks of clay which smear to a great
depth the faces of the trap blocks. A single cross course,
carrying quartz, but no copper, is said to have been met with.
The width of the bed of copper-bearing ground is supposed
to be about 70 feet; not that in any place 70 feet of
productive rock has been found, but when copper has been
lost on one wall, as much as 70 feet have been driven
through what is supposed to be the same bed, and copper

168 Copper Mines of Lake Superior. (April,

found in what has been taken for the other wall. More
than once, cross cuttings for many fathoms have thus
resuscitated parts of the mine where it was feared the
copper had given out altogether. The suddenness with
which the rock will change and lose its metalliferous
character is very remarkable, and affects, naturally, the
productiveness of the mine from year to year.

Copper-bearing beds alternate, however, with barren trap
for a distance of 500 feet, as determined by a cross cut
eastward from the 70 fathoms level of the neighbouring
Pewabic Mine. In the report of the agent of that mine, in
1863, he anticipates that the following copper beds would
be reached at the distances indicated. The results justified
his predictions. From the Pewabic lode, the distances of
the adjacent strata were :—

As ANTICIPATED. As DETERMINED.
Old Pewabic . . . 148 feet. Old Pewabic -. . . 191 feet.
Green Amygdaloid . 285 ,, Green Amygdaloid . 275 ,,
Albany and Boston . 382 ,, Albany and Boston . 380 ,,
Epidote or Mesnard . 465 ,, Epidote or Mesnard. 448 ,,
Conglomerate . . . 520 ,, Conglomerate . . . 500 ;,

To the West of the Quincy and Pewabic lode, little
mining has been done on the lake shore, the Hancock being
the only copper-bearing bed extensively worked.

The heaviest copper lies generally near the foot wall.
Throughout the region the metal is classed according to its
size as mass, barrel, and stamp work. Mass copper is
confined to the other districts; but the Quincy Mine yields
a certain quantity of barrel work, or copper pieces of such
size that they can be separated from adhering rock without
the aid of water dressing. The quantity is, however, small,
compared with that which is scattered in particles so small
that machinery and mechanical concentration alone can
separate them from their matrix. The means used to effect
the separation are the same in all the mills of the district.

The equipment of the Quincy Mine above and below
ground is excellent. The hoisting cars are of heavy boiler
plate. Here and at other mines the cars discharge themselves
by means of a very simple device. They are shaped like
large coal-scuttles, and run on four wheels ; but on the same
axle, and projecting beyond the back wheels, are wheels of
smaller diameter, which, when the car reaches the spot
where it is to be emptied, run up inclines secured on each
side beyond the track. Thus the back wheels are lifted off
the track, while the four wheels remain on the rails and the
body of the waggon, tilted forward, shoots out its contents.

Heretofore it has been the custom in the Portage Lake

» ie

1874.] Copper Mines of Lake Superior. 169

‘shore mines to calcine the rock, and thus render it more
friable ; but following the example of the Calumet Mine, a
hammer like a pile driver has been introduced into the
Quincy ore-house, which reduces the larger blocks to a size
suitable to the Blake crusher, and for hand-picking. The
ore undergoes the following treatment. Discharged from
the hoisting car, it is carried down an incline to the ore-
house, which is on the brink of the steep hill overlooking
the lake. The ore-house is provided with a hammer, under
which, as stated, the largest blocks, weighing often over a
ton, are broken. Such blocks require enormous force to
shiver them, inasmuch as they are generally permeated with
metallic copper in arborescent masses, which so binds the
rock together, that even when broken, fresh force has to be
used to drag the detached stones asunder. In the ore
houses a preliminary hand sorting of the rock takes place
before it is further reduced in size by Blake’s crushers.
Beneath the Blake crushers, other hand pickers are stationed,
who separate still more of the barren or almost barren rock;
and the ore, reduced in quantity to about two-fifths of what
was hoisted out of the mine, is run down the steep inclined
tramway to the copper house.

Stamps are used invariably throughout the peninsula for
crushing the ore. Cornish rolls have been tried, but
without benefit. They become so often clogged with the
larger lumps of copper, and, thus kept apart, so much stuff
passes through uncrushed, that the quantity of raff was
enormous, and the yield of the rolls small. In the Quincy
Mill, when running to its full capacity, 70 square shafted
stamps, weighing goo lbs. each, and with a drop of 16 inches,
crush 232 short tons of rock, or 3°3 tons per stamp head per
diem through screens perforated with 4-inch holes. Two of
- the batteries are engaged upon the barrel work, which is, by
their pounding action, more perfectly freed from rock than
it can be in the ore-house, but has, of course, to be removed
from the battery-box; and all the battery-boxes have to be
cleaned out twice a day. [rom the batteries the ore passes
on to shaking sieves perforated with 23-inch holes, and fine
and coarse are further classified before being concentrated
by entering with a full stream of water a succession of long
triangular troughs which diminish in diameter and depth as
size after size is drawn off to its proper hutch. The hutches
everywhere used are piston hutches with fixed bottoms;
and though in different mills they go under different names,
the differences are in reality trifling. Collom’s jigs are
those most commonly used, and consist of a central piston-

170 Copper Mines of Lake Superior. (April,

_ box divided into two compartments, each of which is in
communication with an adjacent compartment in which the
sieve is fixed and into which the copper that passes through
the sieve falls. The pistons of the two hutches are pressed
down by a single rock shaft, and each piston is lifted back
into position by a spring—a desirable motion—as the down-
stroke is thus sharp and rapid, and the up-stroke slower.
But the hutch is open to the objection that, as each piston
covers only half the corresponding sieve, a wave is propa-
gated from one end of the sieve to the other, which inter-
feres with the regular subsidence of the ore. As the ore is

imperfeCtly sized, some collects in the sieve and is removed -

from time to time, but most falls into the bottom, whence it
is carried away by the flow of water.

The hutches are arranged, with a view to saving labour,
in tiers one below the other, so that the scimpings from one
flow into a hutch on a tier below, and the concentrate is
re-concentrated in like manner. Water being the carrier,
no handling, or very little, is required from the time the ore
is thrown into the stamps till it is shovelled from the
receiving tank as 80 to go per cent copper.

One of the most perfect mills on the lake shore is that of
the old South Pewabic mine—now the Atlantic. In it, the
stuff crushed by Ball’s stamps is concentrated by 112
hutches arranged in seven tiers. There, also, the rotating
German buddle is found to save the copper from the slimes
effectually and cheaply. In the Quincy Mill, the old-
fashioned percussion-table takes out the coarse slimes, and
tributers re-treat the refuse from the whole mill in a sepa-
rate building with English buddles. The coarse concentrate
generally runs to nearly go per cent of copper, the fine,
which cannot be separated, without repeated washing, from
the iron—which we have seen is a constituent of the trap
matrix—sometimes stands as low as 50 per cent; but all
the mills aim at delivering an average of 80 per cent to the
smelting works.

Side by side with the Quincy Mill is the Pewabic Mill, in
which Ball’s stamps are used. A comparison of the tailings
from the two mills, made by Mr. Macfarlane, is interesting.

He found—

Quincy MILL. Pewasic MILL.

Scimpings from coarse 0°06 per cent. From head of run. . 4°93 per cent.
rageing . ... « » middleof run. 3°00 ra

Scimpings from fine ar 4 endiof rn) #2 3S 0a eee
ragging . . a iS. » heap outside of | 0.66

Buddle tailings. . . 046 ,, run-house. od

5). “Gand bank ) 7.” aioo as

. 7%

1874.| Copper Mines of Lake Superior. E75

The Ball stamps may influence the result, through the
volume of water required for their efficient working, and
which, not being separated from the suspended ore, may in
some cases flood the hutches.

The annual reports of the Quincy Mining Company are
models, presenting the work done and the cost of doing it
in clearest detail. From the report for 1872 we summarise
the following particulars. During the year, there were
stoped 5165 fathoms, and sunk in shafts and winzes 808 feet
—say 150 fathoms, and driven 1974 feet—say 329 fathoms.
Assuming the specific gravity of the rock to be 2°7, and
that therefore there are 18 tons to the cubic fathom, there
were broken 101,592 tons of rock. As there were 60,828
tons stamped, about 4-roths of the rock was separated by
hand-picking. The mining, raising, and picking cost for
the year amounted to 283,487°30 dols., or 2°79 dols. per ton
of rock raised, while the milling cost was 64,783°79 dols., or
1°06 dols. per ton of rock stamped. This large amount of
rock yielded 2,804,954 lbs. of concentrated mineral, which
produced 2,276,308 lbs. of ingot. There was recovered,
therefore, only 1°12 per cent of copper from the rock mined,
and yet there were divided, as the year’s profits on working,
210,090 dols.

In 1872, copper brought an exceptionally good price,
selling at 324 cents per lb., but as a set-off, wages were
high, the average wage of miners on contract being 60°62
dols., and the yield of the ground per fathom lower than its
wont.

Distributing the cost over the mineral produced, we find
that, as 2,804,954 lbs. of mineral—which, without making
an allowance for the slight loss in smelting, must have con-
tained 81°r per cent of copper—were obtained at a cost for
mining and concentrating of 461,147°83 dols., each pound
cost 16°44 cents; but when the cost of smelting, trans-
port, insurance, and commission was added, each pound
of ingot cost 22°93 cents U.S. currency, or, say, 20 cents in
gold. Copper has fallen to 25 cents U.S. currency, but as
wages have declined proportionately, and the cost of pro-
duction therefore has been lessened, there is not likely to be
a very serious decrease in the profits. Besides distributing
this large sum among the shareholders, there were added to
construction account,—for permanent improvements likely
to lessen the cost of future produ¢tion,—67,227°65 dols., so
that the real profits of the year were 277,318°35 dols., which
certainly could have been realised only by good manage-
ment and by the employment of every possible labour-

172 Copper Mines of Lake Superior. (April,

saving appliance for the working of an ore yielding but
I‘I per cent of copper.

Another mine even more interesting to the mineralogist,
and more startling in its yield, is the Calumet and Hecla.
It is situated r3 miles from Portage Lake, in a north-east
direction, on a bed of conglomerate, which, however, it is
not easy to identify with any of the beds that abut on the
lake, as the range widens as it approaches the Point and
the beds flatten. While the mineral range at the lake is
7 miles across, at the Calumet and Hecla it is 13 miles
wide, and the dip declines from an average angle of 54° to
38°. Copper had been extra¢ted from conglomerate beds
before the opening of this mine, but never with good
financial results. From the Albany and Boston Mine,
where both a conglomerate and an amygdaloidal bed are
worked, specimens very similar to the rock since yielded by
Calumet were obtained; but the failure of this and other
mines led to a distrust in, and a too hasty condemnation of,
conglomerate mines. It is to be feared the opposite error
may now be run into.

The Calumet Mine was discovered about 13 years ago.
An inn, the half-way house between Hancock and Eagle
River, stood in the forest near where the mine is now, and
was kept by a Cornish man. His pig—so tradition tells—
fell into a pit, which proved to be an old Indian working.
It was dragged out so be-smeared with green that the owner
at once suspected the existence of copper. Since then, two
little towns,—Calumet and Red Jacket,—have sprung up,
and as great a change has taken place beneath the surface
of the soil. Two mines on adjacent locations, though in
the same bed, viz., the Calumet and Hecla, are owned and
worked by one company. This mine has now reached
a depth of ro60 feet on the incline of the bed, or 600 feet
vertical, and one of the upper levels is 3000 feet long. Most
of the copper comes from a bed of conglomerate, in which
a hard red porphyritic pebble is embedded in a cement
of the same rock, and of native copper. ‘The pebbles in the
rich rock are smaller and more rounded than beyond the
rich chimnies. The pebbles composing the conglomerate
are seldom themselves cupriferous, though some of them
are. I have a large pebble from the conglomerate bed
which is identical in appearance with the compact chocolate-
coloured rock of the Quincy Mine, and is throughout per-
meated with a little copper in the same manner as the rock,
but for a depth of about two lines from the surface it
is ensheathed in fine-grained copper, which, as well as the

i'ré

1874.] Copper Mines of Lake Superior. 173

copper permeating it, may have penetrated the pebble or
been deposited around it,—it is difficult to say which. In
the‘ conglomerate also occur boulders of solid copper.
Some are said to exhibit a concentric arrangement of the
copper, but one I had cut through the centre was homo-
geneous in structure, but contained, embedded in the copper,
a few crystals of quartz and felspar.

Interstratified with the conglomerate are thin bands of
copper sandstone, the copper being in fine grains, some-
times deposited pure, at others mixed with. epidote and
quartz or finely-ground porphyry, the laminz easily separable
from one another. In their midst are sometimes embedded
pebbles of copper. Bands of hard compact sandstone, from
the disintegration of the same rock as compose the con-
glomerate, are met with beneath the foot wall, on the hang-
ing wall, or in the bed itself. A specimen in my possession
exhibits successive layers firmly compacted, some of con-
glomerate, others of coarse-grained and others of fine-
grained sandstone, with a surface distin@tly ripple-marked.
The aqueous origin of the bed cannot be doubted, but
whether the copper was mechanically or chemically- de-
posited, it is more difficult to decide. The easier expla-
nation of its occurrence is on the hypothesis of a mechanical
deposition, but, as militating strongly against it, is the un-
doubted fact that the conglomerate pebbles very rarely carry
copper. ‘The effects of subsequent chemical action are
beautifully exhibited in a clay fluccan which, from the
surface to nearly the lowest level driven, lines in places the
foot-wall. In it, embedded in soft clay, derived from
the disintegration of the rock, and which harden into
amass that might almost be mistaken for a piece of trap,
Occur with calc spar, laumonite, and quartz, copper in
dendritic masses, distinctly crystallised. Some of the
specimens taken from the fluccan undoubtedly exhibit
instances of false crystallisation, plainly showing the
impress of the crystals amidst which they were formed, but
others are as undoubtedly themselves crystallised. Vugs
also occur lined with crystals of epidote, and calc spar, and
spongy copper; and through the bed there passes diagonally
what is called a dropper. It is only a few inches wide, but
consists of what is locally called brick copper, which is
accompanied by crystallised silicated minerals, entangled in
which are conglomerate pebbles. It has unmistakable
slickensides, on which the copper is actually polished.

A bed of amygdaloidal trap overlies the conglomerate, and
is in places rich in copper. Some of the amyg edules are

VOL. IV. (N.S.) Z

174 | Copper Mines of Lake Superior. [April, q

completely filled with copper, in others a small nucleus of ©
copper is enveloped in calc spar or epidote, while a coating
of red ferruginous-looking earth lines the cell. A trap, —
similar in appearance, is worked by the South Pewabic
Mine on Portage Lake, but there its richness is deceptive,
for the copper forms in this shell only around an earthy
nucleus.

The long levels of the Calumet and Hecla run through ~
three rich chimnies of conglomerate, the longest about
1300 feet. They dip to the north, and are widening out
rather than otherwise in its lower levels. Between these
rich streaks, large tra¢ts of which will yield a 20 per cent
ore, are others of poorer ground, and others still almost
barren, which are left standing. The average width of the
productive portions is 13 feet.

There are broken, raised, and concentrated, 740 tons of
rock a day. To handle such a large quantity, work has
necessarily to be thoroughly systematised both below and
above ground, and machinery utilised to the utmost.

Each mine possesses six shafts,—or twelve in all,—eight
only of which are connected by levels, and four only used
as hauling shafts. The shafts are sunk at 400 feet apart,
and levels are driven every go feet. Between each two
shafts two winzes are sunk, and three stopes 30 feet high
are opened on each side of each winze, so that eighteen —
stopes are worked between each two shafts. Six feet of
ground are left standing on each side the shafts, and a heavy
arch below each level supports the roof, and gives firm
foundation to the road-way. A wall of heavy stulls pro-
vided with gates at every 10 feet protect the road-ways, and
allow large accumulations to be made in the stopes.
Timbering is a heavy item of expense, as the trap which
composes the roof is very liable to fall out in pyramidal
blocks. The mine-work is done by contra¢t,—stoping by
the fathom, drifting and sinking by the foot. The contractor
must deliver his rock at the nearest hauling-shaft. The
traps are 4 feet apart in the levels, and 4 feet 4 inches in
the shafts, as the cars have to be large to receive the heavy
blocks which break away in the stopes. The miners are
allowed to send to the surface blocks not over r ton weight,
but the cars are constructed to hold 2 tons.

Drifting is done with great economy, by machine-drilling.
Seven Burleigh drills of large size, with 2-inch bits, are
steadily at work in each mine, and it is found that with
them a drift 10 feet wide can be driven at 8’oo dols. less per
foot than a 6-foot drift by hand-labour. This calculation

1874.] Copper Mines of Lake Superior. 175

leaves out, however, the cost of the motor power. In the
Quincy Mine, the same drills are being thrown aside as
uneconomical,—a discrepancy in result which may be
accounted for by the fact that in the Calumet there is a well-
defined salvage, whereas in the Quincy the drifts are run
through solid rock, and grooves must be scooped out
beneath the face of this advancing drift,—an operation not
easily performed with a cumbrous drill.

The ore is broken in two ore-houses, each of which is
provided with a pile driver to shatter the large masses—a
Blake’s crusher with 18 by 24 inch opening, and six smaller
Blakes, with 8 by 15 inch openings, but no attempt is made
at selecting by hand, but all the ore raised passes to the mill.

From the crushers the ore falls into huge hoppers, whence
it is discharged as called for into the railway cars. All the
appliances, in fact, are ona scale such as we are in the habit
of associating with iron mining. A five-mile railroad unites
the concentrating works on Torch Lake with the mine, and
over it two hundred ‘car-loads of 4-ton capacity each are
carried daily.

The mills present no feature of special interest. In one
are three of Ball’s stamps, and in the other four. Six of
these powerful machines are running regularly, and crush
up the whole yield of the mines. To each stamp there are
assigned 20 jigs.

The stamps are steam-hammers. The slide valve is
worked by eccentric gearing, and the piston-rod is inserted
into the head of the shaft, which is g inches in diameter.
The stamp-head is 22 by 14 inches, and weighs 6cwts. Its
upper surface is provided with a bevelled ridge, which slides
into a slot in the bottom of the shaft, and is then keyed
home. When working on the amygdaloidal trap, Ball’s
stamp heads, made with white iron and a small percentage
of Franklinite and tough pig, lastamonth. At the Calumet
Mills they are worn out in six days, but the renewal involves
a Stopping of the stamp of only 50 minutes. Each stamp
works in a separate stamp-box, which is five-sided, and
discharges from three sides through steel plates, perforated
with 3-16th inch holes. Each stampcan crush daily 120 tons
of this exceedingly hard rock, and is said to consume 25 horse-
power; 3000 gallons of water a minute are pumped to the
two mills. The great advantages of using the stamp are
that so much work can be done with so little machinery and
‘In so contracted a space, and that so little time is occupied
in repairs. The Calumet Mills never stop. The Quincy
mill is idle for about one month out of twelve.

176 Copper Mines of Lake Superior. (April,

The scimpings are not clean. They carry from 1°40 per
cent. to 1°80 per cent of copper, 0°40 to 0°80 of which is as
oxide. ‘Twelve tons of copper, therefore, are thrown away
daily.

The Calumet Company publishes no report, but the
following figures are, if not quite, very nearly correct.
There are 1600 hands employed, 260 contracts are set in the
Calumet, and a somewhat greater number in the Hecla.
The cost of breaking a fathom of ground varies from 20°00
to 22°00 dols., and it yields 21 tons of rock; the cost of
dressing exceeds that at the Quincy mine, standing at
1°17 dols. per ton. In 1872 the mine produced 9717 tons of
ingot. The quantity of ore raised daily was about 740 tons,
or 266,400 tons per year of 360 days; and, therefore, as it
produced 9717 tons of ingot, the ore actually yielded 3°6 per
cent of copper. ‘This large amount of work was rewarded
by profit in proportion; for there was distributed among the
shareholders, in 1872, 2,750,000 dols.; and during that same
year large sums were expended in permanent improve-
ments. The result in every respect is unparalleled in
the history of copper mining; and all owners of copper
mines with no such brilliant promise can only hope that it
may not be repeated ; for the effect of a very few such mines
would be most depressing.

Adjoining the Hecla another mine is being opened by the
Osceola Mining Company, which, from surface indications,
will be very rich. The Allonez near by is expected to turn
out well, and on the Isle Royale attention is again being given
to long-neglected conglomerate beds, and the prospect of
success is there good also. The Royale, though belonging
to Michigan, lies close to the Canadian shore. As already
pointed out, the copper formation is largely developed from
Michipicoten to Thunder Bay on the main land and on
Canadian Islands.

With the experience gained on the south shore, explora-
tions could now be conducted on the north, with better
chance of success than heretofore. What little has been
done has revealed the existence of deposits that would not
have remained unworked had they been situated on the
opposite shore.

The following statistics, officially corre@t, are taken from
the annual circulars published by the ‘‘ Portage Lake Mining
Gazette.

The production of all the mines on the promontory for
the year ending Nov. 30, 1873, was as follows :—

1874.] Copper Mines of Lake Supertor. 177
Tons. Pounds.

Calumet and. Hecla, for i eae II,55I 1,938

Naw 30; 1873... +s
Quincy, for year ending Nov. 3°, is 1,680 180
Franklin Pewabic . . . 67. GE673
BPIIEOM Po es ee 285 --
Schoolcraft 5 Wren aout Beak oe 270 1,520
DPR A oe ose a pe vee 72 —
isle Koyale . . se) ay: xa’ ome TAS) Gy Agz
Atlantic, for broken Seasan= sete 14) (sues 464 701
Albany and Boston, brokénseason . . 50 —
Sumner, for year ending with close of
navigation . sree cies 77 ¥
MEMMERESOUUCES ~~. 06 Sa SA re ey ee Us 8 —
Wotals a.4s2-4.. vod Se. LSGEO4S 5,420
Produétion in 1872. cient he Oe 319

RNCKEASE IN TSG 4 o> whee Care ee 2,508 1, LIO

Keweenah Point District.
Central, for year ending Nov. 30, 1873 . 1,081 1,983
Copper Falls, for year ending with close
of navigation . Eros set
SE SM Doce Sel lech onus org aber si gh Se =) Oe, |

Cull . ; 270. ~ 1,204
Delaware, for year ending Nov. 18, 1873 55 742,
Amygdaloid, broken season. . . . 19 303
MUMMETESOUTCES) ¢ Sy sch 3 6 seus enn Sa en ee 184

Oth ges vas cae as oem oe. ee Oke egos

Product in 1872. va, ewe, sek O30) Beg

INCLEASOANG LOGS. ns voane os 945 1,009

Ontonagon District.
Tons. Pounds. Tons. Pounds.
midge. . “150 113 Knowlton . BON 7,004.
National . 131 318 Rockland . Hor” 460

Minnesota. 103 1,700 Mass: > i: 6 868
Blint steel 45 1,356. -Adventure . 2° 1,238
Bohemian. 40 500 Tremont . — 700
“otal. Preteen Liat Bae ky,
Product in 1872. fast Fear 725 1,000

MSCLCASC AMO 7S 1) ta 6-2 187. 1,883

178 Copper Mines of Lake Superior. (April,

Recapitulation.

Tons. Pounds.
Portage Lake Distriét...°..0).. |. 1» 25) ROA
Keweenah Point Distriét’ . . . « % 2,78 gos
Ontonagon- District 15, ts: i csc et saws 537 1,117

Grand total for 1873..° . .« . 18,554 sgjaa@

Or about c<t.- stad ee te 14,810 oe

The Copper Mineral (of about 80 per cent), produced from
1845 to 1874. Tons.

TOA5 10 TOS4 pan o> +3 a on tgs ee ge
1854 to ABIES oc Bip dy ee eee

1858 dma nee) eu ebay ane eee
EOS Owes: vit down. en we a ah Cee Ree
TODO, sks. VSS ee eee

TOOW: . Fs), esc kee eee een ee
TS C2 pret ct eta ia ose ome ane 9,962
BOS eas ook nay ed ee ee ee, oe
EQOA: se Bb pst, «a tuihiics wats eee Oe
TB OR ets No a) fe: Saugus edo scl ai lv) eae
ESO aim seek 0h, Se Ae kee ere es Se
ESO. 15.4 Pale buth Si jusgs shh ee taen 0 Seg
TOR ca Wen ieys lave oot sates vee et eek Soe
ESOGe ace 1s yhskh Mc sae 9 BOR ee a ee
ESTO) cd x 4) jesmiovmane 318 orsign +, 3: ee
EO UT ne: 4 wap oes gel Canetti
TOGO a o> sare one GN beet A
EO73 one sie 4a aut ee et Si

Total .., +. £94,006

About 150,575 tons ingots; value about 82,000,000 dols.
In 1872 there were distributed in dividends—

Dollars.
Calumet and Hecla . « . 2,750,000
Quincy . » 350,000
Pittsburgh and Boston (Cliff 100,000
Central. satis 80,000
Mirnmesotay vss meee eee 50,000
Pramielitny sicme ata we laren oe 20,000
Pawabic’ of Wah as Sait Cas 20,000

DiaiiONAl a2 %. {cb eB Wh awoRhs 20,000

Total dividends . . . 3,390,000
Total assessments . . 190,000
Excess of dividends over assessments, 3,200,000

Pa te wt, =e,

1874.] Copper Mines of Lake Superior. 179

The same mines have been remunerative from their open-
ings, and have yielded 11,810,000 dols.

The paid-up capital on the same mines amounts to the
trifling sum—

Dollars.

Calumet and Hecla . . . 800,000
Omincy Or. Gt or 6 3 S2003000
Pittsburgh and Boston . . 110,000
Cenmale eos te MA Ge soooo
Minnesota 9. 2" 1 | 3 <2. ge 6,000
Beanklin 33 o < <i = 43g70,000
PeWabic) so) oa oe) GWE as he 2355000
Netonal sa *= he = 2 ETO;o000

2,361,000

Increase of dividend overassessments, 9,449,000

There is, of course, another sideto the picture. Of r1I mining
companies formed, only the eight above enumerated and the
Copper Falls Company have paid dividends. Many of the
companies were organised to work locations where there
was no copper at all, and others failed through ignorance
and bad management. ‘The total amount levied, as far as
can be ascertained, has been 19,296,500 dols.

All the copper produced in the Peninsula is smelted at
Hancock on Portage Lake, or at Detroit, branches of the
same establishment. Detroit takes the mass copper from
the Keweenah and Ontonagon Districts, as the furnaces there
are constructed to receiveit. Theroof of the reverberatories
are lifted, and masses of 10 tons lowered on to the bed,
when the roof is replaced, luted down, and the fires lighted.
In the Hancock establishment only the barrel and stamp
work of the Portage District is treated.

The mineral from each mine is smelted apart, and the
copper returned in ingots ; 1800 dols. per ton being charged
for the first smelting, and 12°00 dols. for every ton of slag
and coarse copper re-smelted.

In the Hancock establishment there are seven rever-
beratories and two cupola furnaces.

The copper is smelted without any flux.in the reverbera-
fories, in charges of 16 tons. Eight to ten hours are
occupied in running down, two to three hours in poling, and
three hours in ladling out. When pressed for time nine
charges are smelted a week.

The product is about 78 per cent of the copper as ingot,
a rich slag which is returned to the reverberatory, and a

180 Atonuc Matter and Luminiferous Ether. (April,
poorer slag which is re-smelted in Mackenzie’s blast-furnace
with lime as a flux. The valuable product from the cupola
is a coarse copper of 85 per cent, which is treated in the
same manner as the crude mineral, ‘and a poor slag carrying
not over 3-10ths per cent of copper.

One thousand pounds of coal are said to be consumed in
the reverberatories to every 2000 lbs. of mineral smelted.
Poling is done with birch rods. At Detroit, when poplar
could no longer be obtained, oak was substituted without
affecting the toughness of the metal.

V. ON THE MODERN HYPOTHESES OF ATOMIC
MATTER AND LUMINIFEROUS ETHER.

By Henry DEACON.

HE generally received opinion as to the constitution

of the material universe can be summarised pretty

accurately by saying that all natural objects consist

of either atoms, which are solid centres of force or of

motion,—or of ether, the medium through which the forces

or motions of atoms are transmitted,—or of both atoms
and ether.

A molecule is defined as the smallest piece of any sub-
stance that can retain all the properties of the substance,
and therefore the constitutions of the molecule and of the
substance are identical.

The different qualities ascribed to atoms and to ether are
best reviewed by parallel comparison, of which the following
is an illustration :—

Atoms are inelastic.

Atoms are indivisible.

Atoms do not touch, or atomic
matter is not continuous in all di-
rections.

Atoms coalescing evolve energy, and
in separating absorb energy.

Atoms gravitate.

Atoms possess ‘‘mass” and inertia,
and in motion momentum,

Atoms originate and transmute or
convert motion and force.

Atoms, being inelastic, move as a
whole instantaneously, i.é., motion
passes through or is imparted to the

- whole of an atom, or continuous
atoms, without any lapse of time.

Ether is perfectly elastic.
Ether is infinitely divisible.
Ether is continuous.

Ether coalesces, and is divided with-
out evolving or absorbing energy.

Ether does not gravitate.

Ether has neither ‘*mass”’ nor inertia,
and cannot be imbued with mo-
mentum.

Etheris merely a medium, and can only
transmit motion or force unchanged.

Ether is moved by degrees, and time
elapses as motion passes through or
is imparted to it.

1874.] Atomic Matter and Luminiferous Ether. 181

That these converse qualities are necessary corollaries,
one of another, will be evident on a brief examination; and
whilst incidentally showing this connection, I would criticise
those hypotheses which deny the quality of elasticity to
tangible matter apparently possessing it, and which simul-
taneously create a new and totally different kind of matter
to receive it.

Atoms are described as swinging to and fro in this won-
derful ether, without loss of motion or of energy, and they
consequently either impart no motion to ether, or else
motion must be communicable to it without absorption of
energy. But ether is a medium that transmits motion, or
its necessity and office disappear. If atoms do move ether,
and any energy be absorbed, the motion which is the energy
possessed by the atoms must decrease. If no energy be
absorbed, and yet ether be moved, then either ether move-
ments are arrested without result or energy must be created.
An alternative is a possibility, viz., all kinds of motion may
be imparted to atoms, but only some kinds of motion to
ether.

The question then arises—Is it not easier to make atoms
elastic and matter continuous, and so altogether avoid the
necessity for ether? And before admitting the necessity for
the existence of ether, it will be well to review the known
properties of matter, and philosophically safer to imagine
their extension in the same direCtion, even to an indefinitely
great degree, than to imagine the existence of matter of an
entirely different and unknown kind.

Atomic matter forms an indefinitely small bulk in the
universe. We see the sun, moon, and stars, and all the
host of heaven, but when we calculate their dimensions and
distances, and compare the bulk of these bodies with the
bulk of the sphere of ether containing them, and by whose
aid we know them, figures fail to convey any idea of the
indefinitely small bulk of matter compared with the indefi-
nitely enormous bulk of ether.

Taking the distance of the sun from the nearest fixed
star (a in Centaur) as the radius of a sphere of ether, and
comparing its bulk with the bulk of our solar system, as
being the smallest possible proportion in which atomic
matter and ether can exist, it is as 11,000 trillions to r—a
proportion comparable, perhaps, to a needle weighing I grain
in a bundle of 600,000 million tons of hay, and the true
proportion of ether to atomic matter must be indefinitely
greater than this. Jt puts this question in a somewhat
different light to reflect that the unique and positive qualities

VOL. IV. (N.S.) 2A

182 Atomic Matter and Luminiferous Ether. (April,

of the mass of matter in the universe are, by inference,
without proof, held to differ in essence from the observed
qualities of an indefinitely small fraction of the mass, and
that fraction a totally different kind of matter.

It is a disruption of the idea of continuity, and of the
unity of creation, to assume that the larger and unknown
quantity of matter differs totally from that which is known.
The proposition that we judge of the unknown by the
known implies that the unknown resembles the known, or it
cannot be appreciated; and in this sense scientific method
requires that the unknown properties of ether should be
proved, for they do not resemble any of the known properties
of matter.

The admitted want isa medium for conveying force, or, in
other words, motion of all kinds; and if we ascertain in
what way force or motion is most probably conveyed in
known instances, we shall then know more of the probably
necessary qualities of the required medium.

Grove’s experiment of a silver gridiron on a daguerreotype
plate, placed in the sunlight and connected with a galvano-
meter, proves that the sun’s rays are converted into chemical
action on the plate, electricity through the wires, magnetism

in the coil, sensible heat in the helix, and motion in the

needle, exhausting all the forces in the sun’s visible rays, so
far as known. These forces must all have some property in
common, as they are mutually convertible, and that property
is motion.

All natural motion is, or becomes, rhythmical. No in-
stance occurs to me either of natural uniform motion, or of
motion in a straight line or ina circle. The path of the
planets, as regards the sun, are elliptical, and their motions
accelerate and retard; and as regards space, their paths are
still more complicated. Hence the medium we require to
transmit force must transmit vibratory motion.

Vibratory motion is of two kinds, or may be resolved
into two kinds, viz., vibration across the line of progression,
like all the vibrations or forces accompanying light and the
waves of the sea; and vibratory in the line of progression,
to and fro, like the waves of sound.

The action or force called gravitation is a special property
of atomic matter; on it all the properties of mechanical
“mass” depend.

Many of the concrete arguments as to the conservation
of force turn on the “‘mass” of matter remaining un-
changed under all circumstances: relative unalterability of
‘‘mass” is the chemist’s absolute creed.

Aes.

1874.] Atomic Matter and Luminiferous Ether. 183

Gravitation is called attraction—‘‘ The sun attracts the
earth.” Attraction, as the name of the phenomenon, is
free from objeCtion ; but if attraction be a quality, it is the
same in kind as suction, and suction we know is the name
—and not the explanation—of phenomena. That one atom
or mass of atoms can resist and push, and so impart motion
to another, is comprehensible; but that one atom or mass
should at a distance attract or suck another towards it is
incomprehensible. The fact of the approach is seen, and
is called attraction, but the reasons for it have to be sought.

Prof. Guthrie, in 1869, communicated to the Royal
Society some experimental results, which assist the com-
prehension of attraction. He found that a sounding tuning-
fork attracted such things as the smoke of a candle and
delicately suspended pieces of paper. Due precautions
were taken to show this attraction was the result only of
the vibration, and not of electricity or currents of air, &c.
A tambourine strongly vibrated, and other vibratory sur-
faces, give more powerful manifestations.

In 1870 Sir W. Thomson pointed out that these results
were in accordance with general mathematical laws, appli-
cable to all elastic fluids whose particles were put in motion
by immersed bodies, either vibrating to and fro, or whirling
about in any way. In Guthrie’s experiments the vibrations
were those of sound, which ac¢t to and fro in the line of
progression.

In the sunbeam there are both visible and invisible rays,
but all those rays obey strictly similar laws, as to speed,
reflection, refraction, and polarisation, and hence must be
‘motions of the same kind, and, like hght, are vibrations
across the line of progression.

‘The sun attracts the earth,” and gravity acts when the
sun’s light is absent ; hence the lines or rays of the force
of gravity are independent of the sunbeam, and probably
follow different laws.

So far as attraction is concerned, Guthrie has shown that
to-and-fro vibratory motion suffices, and, as all known
effects of gravity can be shown to follow from attraction,
gravity itself may be the effect of to-and-fro vibrations. It
is necessary, moreover, that these vibrations be such as the
vibrations of light, &c., do not affect.

Mechanically, all motions that are at right angles to each
other proceed without what is technically known as “ inter-
ference,”’.or, so to say, proceed uninterruptedly. A cannon,
whose axis is parallel to the horizon, may project balls with
very small and with very great velocities, but each ball will

184 Atomic Matter and Luminiferous Ether. (April,

touch the same horizontal and lower plane at the same
time, that time being the same as would be occupied by the
fall of a ball in a vertical line from the cannon’s mouth to
the same horizontal plane. ‘To-and-fro vibrations would, in
this sense, be unaffected by transverse vibrations which are
at right angles, and thus to-and-fro vibrations of gravity
would be unaffected by the transverse vibrations of light, &c.
Gravitation vibrations, if ultimately passing into space,
would cause a body to lose weight.

It is supposed that suns and planets lose heat from the
motion they impart to the rays or vibrations of radiant heat,
but the effects of the sun’s and planets’ loss of heat are not
now astronomically observable, and the effects of the loss
of gravity and of heat may perhaps be observed simulta-
neously. As, however, gravity and heat rays are not
of the same kind, there is probably a difference in the
rate of their dissipation, and the force of gravity may be
the weakest but most enduring. In the sunbeam there are
both light and heat rays whose vibrations are of the same
kind. Incandescent bodies yield similar duplex rays, but
their radiant light is extinguished before their radiant heat ;
and we may conclude that if the sun’s condition changes it
will be dark long before it be cold; and as similar vibrations
are found to dissipate energy, at different rates, dissimilar
vibrations most probably follow the same rule.

According to the axiom of the conservation of energy, the
rule as to its dissipation is, that energy is parted with or ab-
sorbed by work done. A feeble force, or one able to perform
little work, absorbs only feeble energy to originate; con-
versely, a powerful force owes its origin to much energy,
and the most powerful force may be the first dissipated.

In calling gravitya feeble force, the necessity of measuring
a force becomes apparent. Light, heat, electricity, &c., are
termed imponderable forces. This phrase, by implication,
admits the possibility of ponderable forces. Is oxygen, for
example, a ponderable force? An examination of this
question will serve to show the sense in which these terms
should be used. Assume oxygen to be a ponderable force,
and it is at present impossible to refute the assumption by
experiment. Andrews compressed oxygen to about the
density of water, and it remained then, as ever, invisible and
intangible, except by its forces, its ponderability included.
Elements unite with oxygen, and fresh substances of dif-
ferent properties are produced. Heat unites with or is
absorbed by ice, and water is produced. ‘The allotropic
forms of phosphorus and of sulphur, and many other

a

1874.] Atomic Matter and Luminiferous Ether. 185

instances, will occur to every reader’s mind where a substance
of different properties is produced by the action or absorp-
tion of an imponderable force. A ponderable force would
only add weight. If ice became heavier in melting we
should say matter was added to it, only because it increased
in weight. Radiant heat adds volume as well as sensible
heat to the body that absorbs it, so that the addition of two
qualities to a substance by the action of one force is not
rare. Hence, in the attempt to prove that gravity is a
feeble force, the difficulties of measuring forces by gravity,
and of the conception of forces as apart from matter, must
be remembered.

In many respects gravity well deserves to be called a feeble
force. Our atmosphere sustains a load of 15 Ibs. to the square
inch ; we call it a great load,—+. ¢., a great result of gravity,
—but do not equally appreciate the-effort of the air in
resisting it; it requires an _intelleCtual effort to say the two
are equal, and then the magnitude of this effort of gravity
does not seem comparatively large.

Prof. Osborne Reynolds has recently shown that a small
glass tube, sufficiently strong to be safely used as a gun,
with gunpowder, so as to propel little brass rods through a
half-inch board, was shattered into the minutest dust when
partly filled with water and acharge of electricity discharged
through it. A similar result, if obtained by gravity, would
have required the pressure of a weight to be measured by
many tons on the square inch. ‘This experiment was made
to illustrate the effect of lightning upon splitting trees,
shattering stones, &c., and Faraday showed some years ago
that more electricity was concerned in a dew-drop than ever
was manifested in a thunderstorm. Many trees and stones
are often shivered to fragments by one storm, showing that
an equivalent to enormous mechanical or gravitation forces
is latent in a part of one of the forces that builds up a drop
of water.

Heat expands bodies, and requires an enormous me-
chanical or gravitation force to resist it. The rays of the
sunbeam, if converted into mechanical force, would far
exceed anything we can realise; and heat may be said to
act paradoxically. Its absorption develops mechanical
force, and so does its subtraction from freezing water and
from solidifying bismuth.

The sunbeam also contains actinic or chemical rays,
probably the most energetic of all, and for the me-
chanical equivalent of chemical energy we may again go
to Faraday for an illustration.

186 Atomic Matter and Luminiferous Ether. (April,

The metal potassium, like other metals, is mechanically
compressible only to a very limited extent : probably no means
are known by which so great a weight or pressure could be ap-
plied as to compress, say, 450 units of it into the bulk originally
filled by 400 units. Faraday points out that a space originally
filled by 430 units of the pure metal potassium, if filled by the
same potassium when by chemical action made into carbonate
of potash, would then contain 686 instead of 430 units of
the same metal, and, in addition, 2744 units of oxygen and
carbon. He shows that this power of compression is not
restricted to carbonate of potash, nor to potassium, but is
even more strikingly exemplified when some other sub-
stances enter into chemical combination. No other force
measured by gravity gives parallel manifestations.

Comparing the mechanical equivalent of gravity with the
same equivalent of other forces, gravity is thus proved to
be feeble, and, requiring little effort to originate it; it yields
small effects, and is the more likely to be very slowly dis-
sipated.

Perhaps an objection may be made that, although astro-
nomically we see no effects of the loss of heat in the sun
and planets, yet we see a hot body loses heat on the earth,
but do not see it loses any weight whatever.

The hot body is noticeable because it is hotter than its sur-
roundings. Itonlyloses the excessof heat it had,and becomes
cooler than the earth only when its surroundings are excep-
tional, and are, so to say, means through which its heat energy
escapes, and it remains of the same heat as the earth, when
subjected to the same conditions. Heat is a mode of motion;
communicated heat is communicated motion; by substi-
tuting gravity for heat we can say gravity is a mode of
motion, and communicated gravity is communicated motion.
All substances are influenced by the motion of heat;
analogically, all substances are influenced by the motion of
gravity. The earth’s heat maintains the heat in its parts,
and the action is reciprocal; so, too, the gravity of the
earth and its parts are reciprocal, and similarly of all related
gravitating bodies, and hence no loss of gravity is apparent.

Mr. Crookes’s recent experiments on the weight of bodies
in vacuo prove that heat and gravity have some connection,
and motions at right angles to each other do influence one
another, although each passes on distinctly. One of the
cannon-balls before alluded to moves in a path which is
neither wholly vertical nor horizontal, although the vertical
and horizontal planes it passes through are those through
which each force alone would have sent it in the same order

1874.] Atomic Matter and Luminiferous Ether. 187

in the same times. Vibrations at right angles may there-
fore have some connection, as on the principle of the well-
known parallelogram of forces.

All radiating vibrations which absorb energy in their
beginning, and evolve it when they are arrested, necessarily
follow the same law, of effects lessening in proportion to the
square of the distance from the centre of radiation. The
effects of gravity are therefore consistent with its being a
force due to radiant vibration.

Before quitting this point of the question, the veloci-
ties at which vibrations are known to be transmitted
through matter require some notice. The ordinary
surface-wave on water (a vibration across the line of
progression) moves with a velocity of about 1 foot per second.
The waves of light, vibrations of the same kind, pass
through water with a velocity probably as corre¢tly repre-
sented by 200,000 miles a second. And eletricity passes
through some metals still more rapidly. The waves of sound
(to-and-fro vibrations in the line of progression) pass through
water with a velocity of about 4000 feet per second. As there
are certainly two varieties of transverse vibrations, there may
be at least two varieties of to-and-fro vibrations, and, if so,
the velocities of the varieties of each kind may bear the same
or similar proportion to each other, and the velocity of
transmission of the vibrations of gravity may probably be
at least 4000 times as rapid as those of light.

The medium between atoms has to serve for the pheno-
mena belonging to latent or potential energy, or the energy
of position. This energy is of two kinds: one as whena
weight is raised; the other kind such as a coiled or bent
spring possesses.

The sunbeam reaches us, say, eight minutes after it left
the sun. The waves of light present to us at any instant
are so disconnected with others before and after them that
both or either might be arrested without our immediate
knowledge. In fact, as the earth sweeps on its course it
cuts into fresh lines of waves, and leaves broken lines to
continue their course. Each spot on the earth receives
part only of one of the lines of waves of light reaching
from the sun, and a still smaller proportion of the lines of
those waves whose sources are the sun’s we call fixed stars.
A floating straw is moved on a pond’s surface by the waves
proceeding from a stone, which fell at a distance, some time
before ; and, although the spot where the stone fell is still,
the straw moves.

All radiated vibrations follow the same rule, and “‘ energy

188 Atomic Matter and Luminiferous Ether. (April,

of position” is due to the fact that the body, in moving,
will receive, from the then existent vibrations, an energy the
exact equivalent of the vibrations arrested, and probably,
but not necessarily, the equivalent of the energy absorbed
in placing it in position.

That energy of position is really due to the circumstances
surrounding the position, from time to time, is perhaps still
more evident from considering the difference in weight of
the same body at the earth’s poles and equator, 194 lbs. in
the former position weighing only 193 in the latter one.
But one of the clearest proofs is that of an ele¢tro-magnet
and an iron bar. For convenience we may imagine the
magnet placed vertically, and the iron bar upon it. The
bar, being raised, acquires an energy of position due both to
the magnetic attraction and force of gravity. It absorbs
energy to raise it, and evolves its equivalent in its descent.
But it may be raised whilst the electric current is stopped,
and fall: whilst it is passing. It would then evolve more
energy in falling than was employed in raising it. Vzce versa
if raised whilst the current passes, and falling when it is
stopped ; and, evidently too, variations in the electric current
would vary either the energy required to raise the bar to any
given position, or the energy of position after the bar is
raised. Briefly, then, energy of position of this kind is in
every case dependent on the forces or motion of the present,
and is disconnected from the forces, or motion, or energy of
the past; in its nature it is variable and accidental.

But latent or potential energy of another kind may and
probably does exist, viz., the latent energy of a bent spring;
but this raises the question of elasticity asa quality of tangible
matter, and it is difficult or impossible to comprehend the
possibility of this form of energy, except the quality of
elasticity be assumed. A compressed gas on the atomic
hypothesis is elastic because the paths of its atoms are
shortened, and their impacts more frequent; it is not a
quality of the gas, but of its mechanical structure, and is
dependent on the motion of its particles. But on appealing
to experimental results, we find when any tangible
substance is broken up the transmission of vibration is
interrupted. Beginning with a cracked bell, we may pass to
Tyndall’s recent proof that alternate layers of gas of
different densities retard sound, and twenty-five alternate
layers of coal gas and carbonic acid gas, forming a column
about four feet thick, he shows are impervious to sound.
The same gases diffused through each other are pervious to
sound. Similar kind of phenomena occur in similar

1874.] Atomic Matter and Luminiferous Ether. 189

circumstances with other vibratory motions, as light and
radiant heat. Hence, two gases diffused through each other
possess a quality which is not the average of the same gases
alternated in small bulks, but which appears to be of a
distinct kind. No evident solution of this problem occurs
on the atomic theory. If ether permeate all bodies, and be
the medium of transmission, it is both a conductor and non-
conductor of electricity, both opaque and transparent to
light, both diathermous, anda heat-absorbent; but as this
is an evident absurdity, the utmost transparency of solids
and fluids to light, radiant heat, electricity, sound, &c., is
due to unbroken atomic continuity in at least one dire¢tion.
But the metal potassium before alluded to is a conductor of
electricity, and, therefore, its substance is continuous.
‘Faraday, however, showed that 680 parts of it together
with 2744 units of other substances could be compressed
into less space than was originally filled with 430 parts of
potassium itself; and it is difficult to avoid the conclusion
that potassium is elastic; and, if potassium, then all other
bodies—solid, fluid, and gaseous.

It is difficult to trace mentally the act of elastic disturb-
ance within the substance of a body, but this difficulty is
equally great with ether, and not more difficult with tangible
than with intangible matter, and it is more in accordance
with scientific method to connect a known or evident
property with a known substance which exhibits similar
qualities, than with an unknown substance whose mere
existence is hypothetical.

Attraction of cohesion, one of the most evident properties
of atomic matter, is intimately related to elasticity ; but the
atomic theory does not explain how. As the present object
is rather to criticise an existing theory than to construct a
new one, it is unnecessary to account for what the atomic
theory leaves obscure ; but it is somewhat probable that the
true explanation lies in a direction we proceed very incom-
pletely to indicate: mechanically, motions that coincide
coalesce without jarring or ‘‘interference;’? motions that
do not coincide jar and tend to separate.

Another experiment of Tyndall’s exemplifies these remarks.
Holding a glass tube of about six feet long, and two inches
diameter by its middle, he rubbed one end of it with a wet
cloth and caused it to emit the sound of a musical note from
the longitudinal vibrations thus excited. The free end of
the tube was shaken into pieces; each piece a ring, and
many of. them with cracks quite round the tube, but not
completely through its substance. It would require a
- VOL, V. (N.S.) 2B

190 Atomic Matter and Luminiferous Ether. (April,

weight of about 100 tons to produce the same effect by
dragging the glass tube asunder against its attraction of ©
cohesion.

The vibrations, due entirely to the elasticity of the glass,
passed to and fro the length of the tube, and were reflected
from the ends and from any intermediate ‘‘nodes.”; SA —
series of reflected vibrations thus met a dire&t and distin&,
and not coincident, series of vibrations; and this jarring or
interference of vibrations, themselves dependent upon the ~
elasticity of the glass, sufficed to overcome, simultaneously,
the attraction of cohesion of its substance at many different .
points of its length, thus showing that cohesion and elasticity —
are intimately related, and that the form of the motion
governs much of its effects. This latter fact is also
exemplified in many other ways. Amongst these are Abel’s
experiments on exploding gun-cotton by detonating powder.
A small portion of common fulminating powder produces a
most powerful explosion of the cotton, under conditions
where a much larger quantity of the more violent explosive,
chloride of nitrogen, simply disperses the cotton, and will
drive some of its unaltered fibres into oak, &c., without
producing any remarkable explosion of any part of it.

Amongst other instances are Professor Reynolds’s bursting
of the glass tube by an ele¢tric spark, and the difference of
fracture in a pane of glass by a slow moving stone and by a
rifle bullet.

The effect of a rapid blow on water in an open vessel is
another illustration. A ‘“‘ Prince Rupert’s drop,” broken
under the surface of water in an open phial, will breaka
phial that is unharmed if water is absent.

A faét connected with the spheroidal state of liquids\is
also significant. A quantity of water on a red-hot solid in
the well-known spheroidal state is exploded if struck a
smart blow, or if the water be dropped upon the heated
surface from a sufficient height an explosion ensues.
Recently, at an alkali works in Newcastle, serious damage
followed from this cause—the instrument being a falling hot
**black-ash ball.’”* | A still more serious case is on record of
a copper foundry being destroyed from a workman spitting
into a large quantity of melted copper.

One remarkable characteristic of molecules has been
pointed out by Sir John Herschel, who says, in effect, that
the exact equality of each molecule to all others of the same
kind gives it the essential character of a manufactured
article, and precludes the idea of its being eternal and self-
existent, and this thought well deserves careful examination.

1874.| Atomic Matter and Luminiferous Ether. IgI

There appears no difficulty in appreciating the very precise
equality of two distin¢t but otherwise identical musical
notes. We can understand that two bodies may make the
same number of vibrations in a second, and that two sounds
may be identical, excepting in order of time. We can under-
stand that the vibrations of light and heat of two distinct lines
of rays may be of the same length, amplitude, and frequency,
and so give the same appreciable results of light, colour,
temperature, and mechanical force.

When, however, we examine natural objects, we never find
two alike; there is always an observable difference. In this
sense the multitude of individual faéts is overwhelming;
and two natural objects, whose only difference is that they
occupy different portions of space, or occur at different
times, are unknown. ‘There are differences between two
tuning forks, each sounding the same note. We must
conclude that, as each fork changes with use and time, so it
has changed between two soundings, although its sounds
may remain unaltered.

Different but otherwise identical vibrations of sound and
light have been compared, and have always been found to be
the same ; whilst all attempts to prove or to obtain perfect
resemblance between any two solid, or, so to say, natural,
objects, have been failures. Hence, identity of all active
properties is more probably due to identity of motions than
to identity of quantities or forms of the substances.

Adding to these conclusions the almost axiomatic idea
that all force is motion, the enquiry, as to the necessity for an
elastic ether, is restricted to the capacity of tangible or
atomic matter for conveying vibrations of all kinds.

It is unnecessary for this purpose to discuss the question
as to the definite size of a molecule, defining that term as
the smallest portion of a substance that will produce the
phenomena, whereby the individuality of the substance is
recognised. There is no @ priort reason why that molecule
should not be of a definite size in comparison with the
definite number and kind of vibrations it has to originate or
transmit, and by which alone its characteristics are recognised.

Sound is not produced by one movement, but by a series
of movements, and one movement alone is inaudible.
Similarly it is probably true that all observable phenomena
of this kind are due to a not indefinite succession of
vibrations. Mentaily, we can isolate each vibration, but
practically no single vibration can produce a manifest
phenomenon, such as we call sound, light, heat, or the like ;
and as one of the results of all chemical action is measured

192 Atomic Matter and Luminiferous Ether. (April,

by weight, the force called gravity must bear its part, and,
hence, molecules may also be of a definite weight. To this
extent there appear to be no analogical or inferential grounds
for objecting to this definition of molecules.

The theoretic formule for the velocity of the propagation of
soundshow the velocities to be the same for each gas whatever
be the pressure supported by it; and Regnault, by experiments
on the large scale with pressures varying in the proportion of
1 to 5, has verified this law. This law is of general application
to all vibrations in elastic media; hence, if light be propagated
with an ascertained velocity in air, at the earth’s surface, it
should pass with the same velocity when air is indefinitely —
attenuated. Astronomers do find that light passes through
our atmosphere, and through stellar space with the same
velocity ; and so far, therefore, as the sun beam is concerned,
this space may be filled with attenuated air, instead of the
hypothetic ether, if the air be elastic.

The preceding remarks have incidentally illustrated the
axiom that all force is motion, and different forces (gravity
included) are different modes of motion; but passive
existence, and consequently passive qualities, ready to yield
more or less to motion of some kind, appear also to be
necessary and axiomatic attributes of matter. We cannot
make lace without mechanism. The machine possesses
various passive qualities; amongst them is the capacity
under certain conditions of making lace by the expenditure
of energy in the form of mechanical, as distinguished from
molecular, motion. Various machines differ in their capacity
of transforming an identical energy, and producing from it
various results. Whilst different chemical compounds may be
compared to different machines, all constructed out of a few
materials, and still fewer mechanical elements variously
grouped, all the different natural forces, 7z.e. vibrations of all
kinds and forms, must be conveyed by one and the same
quality, and that most probably a passive quality, common
to all matter.

Continuous atomic matter appears to possess this quality
to perfection. The waves of the sea are in number
complicated beyond computation, and cross each in all
possible directions. ‘They descend below the surface, and in
a definite zone we perceive the substance of the sea must be
in intestinal motion correlated to the visible motion of its
surface. The waves of a lake of gas (and those of
a large mass of carbonic acid gas, just rendered
visible by suspended carbonate of ammonia, are mentally
reproduced as these lines are written) are at least as

To RA Se AS gai

ae

a

1874.] Atomic Matter and Luminiferous Ether. 193

interesting, philosophically, as the waves of the sea, and
enable us more easily to understand how multitudinous
vibrations may coexist in an elastic body which as a whole is
stationary.

Sir Charles Wheatstone’s experiment helps to carry this
same idea much further. The tones of a tune played ona
piano are conveyed through a wooden rod, and rendered
audible in a distant room. Various fundamental notes of
different intensities and in different sequence as to time,
accompanied by their overtones or clang, and all the
mechanical noises due to the mechanism of the piano, &c.,
pass through a wooden rod, thinned at its end to stand
without interruption between two strings, and so rest on the
sounding board.

The wooden rod may be replaced by a glass rod, or bya
metal rod, or by a column of fluid. ‘That air conveys these
sounds is our daily experience.

At the same time that sonorous vibrations pass, we may
pass heat, light, electricity, or magnetism, and if a suitable
fluid medium be employed, mechanical waves and motion
and chemical action may also simultaneously proceed.

Through the Atlantic cable two messages can pass at the
- same time from different directions. We talk across each
other, and at the same instant hear many sounds from
different directions; and an indefinite number of people can
together see numberless rays of light reflected from the
same point on a refleCting surface, and countless rainbows
refracied in one rain drop.

From a seed may grow a tree, and from the tree a forest.
The germinating cell or group of cells in the seed possess
motion of such a form that its communication is the cause
of this development; and the development from this cause
occurs in, and is communicated by, continuous atomic
matter. In continuance and complicity, the communication
of motion constituting vegetable and animal vitalism or
growth has no known parallel. Tangible matter, therefore,
does transmit forms of motion of all kinds, and appears to
be elastic; and if elastic, needs no medium for transmitting
motion, and the so-called necessity for the hypothesis of
ether disappears.

The conclusion, then, must be, it is more philosophical to
endow appreciable matter, even hypothetically, with the
qualities it appears to possess, than to create matter of an
unknown kind in order to endow it with qualities we see,
but refuse to appreciate, in matter that lies before us.

( 194 ) (April,

V. EXHIBITION OF APPLIANCES FOR THE
PRODUCTION AND ECONOMICAL USE OF FUEL,

IN CONNECTION WITH THE

SOCIETY FOR THE PROMOTION OF SCIENTIFIC
INDUSTRY, MANCHESTER.

been to concentrate the attention both of producers

and consumers of fuel upon the great question of
economy, and through the medium of the Society to bring
together those who are concerned in the speedy solution of
the problem.

The following was the original classification to which the
council asked the attention of the exhibitors. No exhibitors
have been named in classes 6 and 7; and 3 and 4 it has
been found convenient to amalgamate.

(1). Appliances which may be adapted to existing steam
furnaces, &c., whereby an improved combustion of the
fuel is secured, and a direct diminution in the quantity
required is effected.

(2). Appliances which may be adapted to existing steam
boilers, &c., whereby the waste heat of the flue gases
or of exhaust steam is utilised.

(3). Appliances which may be adapted to existing steam
boilers, pipes, and engines, whereby loss of heat from
radiation and conduction is prevented.

(4). Appliances which may be adapted to existing steam
boilers and engines, enabling them with safety to realise
the great economy resulting from the use of high
pressure steam or superheated steam.

(5). New or improved furnaces (using solid, liquid, or gaseous
fuel), boilers and engines of all descriptions, specially
adapted for the saving of fuel.

(6). Apparatus which, by producing a cheap and abundant
gaseous fuel, will supersede the costly carriage of coal,
obviate the present enormous waste attending its use in
the solid form, and condense and save the valuable
sulphur, ammonia, and other by-products of the distilla-
tion now injuriously affecting iron and other smelting
processes, and in a vast number of operations discharged
as poisons into the air.

(7). Apparatus or engines for obtaining power advantageously
from heat through any other medium than steam.

ae chief object of the promoters of this Exhibition has

1874.| Fuel Economy. 195

(8). Natural and artificial fuels of all kinds.

(9). Coal-cutting machines. Peat-manufacturing machines.

(10). Domestic and other fires, stoves, ranges, and apparatus
of all kinds (using coal, gas, or other fuel) for cooking,
and for warming rooms and buildings.

(11). Mechanical or other arrangements for securing the
delivery of proved weights of fuel to the domestic
consumer.

Entering at the south door is seen a wooden model of
Davey’s Patent Differential Expansive Pumping Engine,
200-horse power, for the New Hartley coal-pit ; the engine
is intended to lift 1500 gallons of water per minute 420 feet
high. This is exhibited by Hathorn, Davis, and Co., of Leeds.

On the right-hand side of the building the first object
which engages our attention is Erskine’s Patent Economiser.
This consists of Io horse-shoe pipes about 4 inches in
diameter, and all conne¢ted; these are placed in the flue
communicating with the chimney. The waste heat from
the boiler fire encircles these pipes, and causes the water
which flows through them to enter the boiler at a temperature
of 280° F.; and as these pipes are liable to become covered
with soot and dust, instead of having a scraper, as in many
instances is done, a pipe about 2 inches in diameter passes
through the entire length of the horse-shoes, which is
perforated with holes about 6 inches apart. The pipes are
allowed to get hot, and the steam is now blown on to them,
which, according to the inventor’s statement, effectually
cleanses them. ‘The advantages which Mr. Erskine claims
are, that from the peculiar form of his economiser, it causes
no diminution or obstruction to the draught in the flue. It
maintains a thorough circulation of the water through all
the tubes, thus preventing the accumulation of scale; it is
easy of access to every part, so that if one of the pipes is
‘injured it can easily be replaced.

Andrew Bell shows a fine set of spiral economisers; they
have the exact shape of three condensing worms put
together. Each worm consists of 70 feet of pipe, and a
three-coil machine is sufficient for a 4o-horse boiler. Mr.
Bell has shown great ingenuity in the casting of these iron
worms; it would not be an easy undertaking to cast the
worms in one piece—in fact practically impossible. The
spirals are cast in half circles, having a spigot and facit
joint. The joints fit so well into each other, that the circle
can be formed and lifted without the joints parting ; moulding
boxes are put round these joints, and hot metal run upon
them, so that it forms a perfect spiral when they are all

196 Fuel Economy. (April,

connected. This arrangement does away with all flange
joints, so that no leaking can possibly occur, and also

secures a perfectly smooth surface for the action of the |

scraper, which revolves, ascending and descending according
to the spiral form of the coil. It is said that a saving of at
least one day’s consumption of fuel per week is effected.
The water having a continuous circulation, all sediment is
held in solution and passes through the coils, thereby
avoiding deposit. Each coil is tested to a pressure of 300 lbs.
per square inch before leaving the works. Economisers of
various forms make a great show, and it is difficult to say
which is the best. |

Messrs. Twibill, of Manchester, exhibit a fine perpen-
dicular economiser, which consists of a collection of tubes
set vertically in the flue. These tubes are tested to a
pressure of 500 lbs. to the square inch. Some experiments
were performed some time since after the heater had been in
use for some time. ‘The first test was taken at six o’clock
on Monday morning; the temperature of the water in the
pipes was 140° F. At four o’clock on the same day it had
risen to 284° F., on Friday morning at six o’clock the
temperature was 250 F., and at four o’clock the same day
it had risen to 310° F.; and the average temperature of the
water throughout the week was 273° F. An experiment was
performed at Messrs. Romaine and Callender’s mill, and the
average temperature of the water was 295 FI’. The scrapers
are peculiar to Twibill’s machine; they meet round the
tubes and have chisel edges, which, by a special arrange-
ment, press against the tube, and actually cut off the soot
and tarry matter which accumulates upon the pipes.

Messrs. Green, of Wakefield, exhibit the finest vertical
economiser; the joints of their economiser are all turned
and bored socket-joints, ‘‘ metal and metal” forced together
by powerful machinery expressly adapted for the purpose.
Their economisers are in operation to 65,000 boilers,
representing 2,500,000 horse-power.

Nield’s improved fuel economiser is on the same principle
as Andrew Bell’s. ‘This economiser is arranged in sections,
each section consisting of a number of cast-iron ring-shaped
pipes, through which the water is caused to circulate. The
inlet and outlet passages of each ring are close together;
and as this is the sole joint, and the only fixed point in the
ring, itis quite impossible that the expansion and contraction
of the ring can affect the joint in any way; this is a very
important advantage, and is peculiar to this economiser.

_1874.] Fuel Economy. 197

Robert and Joseph Ellis, of Liverpool, show some ingenious
fire-bars, in which the water, before it enters the boiler, is
made to traverse these bars, and is raised to a temperature
_ of 300° F. There are many other appliances for heating the

water before entering the boiler; there is the Paxman
Water-Heater, in which waste steam from the engine is
condensed, and so made to heat another supply of water,
and the water is pumped into the boiler at a temperature
of 200°. ;

Goodbrand and Holland show a coal-cutting machine. It
is a 27-inch self-acting right or left hand coal cutter,
constructed specially for the Wharncliffe Silkstone Coal
Company to undercut their medium hard coal at bottom of
seam.

Messrs. Ommanney and Tatham also have Winstanley’s
coal-cutting machine. ‘This machine is designed for holing
in mines which are worked on the wide work or long wall

system. It is driven by compressed air, the pressure
required being from 20 to 30 lbs. per square inch, according
to the nature of the coal to be cut. The height of the
machine is 22 inches, and the gauge of the wheels can be
made to suit any ordinary colliery tramway. The cutter
holes its own way into the coal, cutting from nothing up to
3 feet or more in depth, the thickness of the groove being
3 inches. The small coal made by holing represents only
from 25 to 35 percent of the quantity of small coal produced
by hand holing. The average rate of holing in hard coal,
with a pressure of 30 lbs. per square inch, is 25 yards per
hour, including stoppages, and this may be considered to
equal the work which would be done by at least thirty men
in the same time.

Messrs. Hanworth and Horsfall exhibit a self-feeding
smoke-burner and fuel-economising furnace. The draw-

back to it is the complicated arrangement for effecting
the object. The bars are moved by egg-shaped wheels,
which gives them a forward and backward motion, and

the coal is allowed to fall upon them by means of a

sloping plane..

Some experiments were performed at Lacy Brothers,
Callis Mill, near Hebden Bridge, upon two of Galloway’s
New Patent Boilers, 28 feet long, 7} feet diameter, and
working at go lbs. pressure, one of them fired by hand,
the other by the self-feeding furnace. The results of tests
show a gain of 15 per cent in favour of the self-feeder.

VOL. IV. (N.S.) 2C

198 Fuel Economy. (April,

Results of Tests, fanuary 22, 23, 1874, at Messrs. Lacy’s.

Pounds of
Fitine Time. Coals Water Water
tt in hours. Used. Evaporated. Evaporated
. per lb. of Coal.
Cwts. Lbs. Gallons.
Hand-fired . . I0°5 Feat te 7150 8°42
Self-feeding . . I0°5 69 26 7700 9°93

William Young, Brothers, Queen Street, London, show a
Smoke Preventer with spiral bars, for every description of
furnaces, grates, and stoves. By means of this apparatus
the fuel is introduced at the bottom of the fire, under the
burning coals, and thus the production of smoke is prevented.
The smoke preventer is composed of spiral bars mounted on
an axis, which is moved by hand or machinery each time
coals are required ; in an ordinary fire-grate, there is a small
trough at the bottom, in which works an axis carrying two
vanes of fire-bars. The coal is put into the trough, and the
poker is used, not to poke the fire, but to turn the fire-bars
round, thus turning the fresh coal under the ignited coals.

Messrs. Piercy, of Birmingham, exhibit an apparatus
called a Mechanical Stoker, patented by Dillwyn Smith. It
is a very ingenious arrangement for feeding the furnace
mechanically. In front of the fireplace is a cylinder about
4 feet long and 8 in diameter; up the top of this is a hopper
which will hold about 5 cwts. of coal. In the cylinder
revolves two Archimedean screws, one right and one left,
which carries the coal into chambers, one underneath each
screw. In these chambers revolve two fans, which throw
the coal the whole length of the furnace, the quantity of
coal being regulated by the requirements of the boiler.

Mr. Sudlow, of Oldham, exhibits a Rotary Engine, the
advantages of which are as follows:—It obviates the dead
points or centres of the crank, and consequent ever-varying
leverage, the steam acting at an uniform distance from the
centre throughout its entire travel. It also gives an increased
longitudinal capacity, wherein to expand high pressure
steam without incurring pressure, asin the case of compound
engines; also, where necessary, the flywheel can be entirely
dispensed with.

Reese and Gledhill show Wright’s Patent Movable Fire-
Bar. ‘The rapid and complete manner in which they operate
upon the combustible matters used decreases the formation
of clinker or slag, by removing the refuse while in a state of
dust before it has time to cake into a clinker. By their
peculiar advancing and retiring action, the slag that is formed
at the extreme back of the surface is brought, with every

ow are

1874.] Fuel Economy. 199 °

successive action of the bars, and deposited on the dead-
plate or mouth of the furnace. This is an advantage of the
greatest importance, as the removal of slag from the extreme
back of furnaces has always been attended with great
difficulty and the periodical destruction of the fire. A
thorough and complete combustion is effected by the
breaking up and removal of the slag, and consequent free
admission of air between the bars, and a large saving is
effected in the usual consumption of coal.

Mr. Gall, of Halifax, shows a Patent Self-Acting Smoke
Preventer, with the recommendation that it will reduce the
smoke emitted from the chimney by seven-eighths; andshould
this result not be attained the purchaser may, within one
month, return the Preventer to the patentee, and no charge
whatever will be made.

Dingley and Son, of Leicester, exhibit Lake’s Coal
Economiser, which, according to the statement of the
patentee, will save from 10 to I5 per cent on stationary
boilers, and from 20 to 25 per cent on multitubular boilers.
This arrangement consists of a conical, fluted, or corrugated
valve, applied to the rear end of the tube, and capable of
being adjusted as required; the openings round the valve
being the outlet for the draught, and which are proportioned
to the area over the bridge, cause the fire to be kept in close
contact with the plates around and throughout the entire
length of the tube, ensuring more perfect combustion and
equal distribution of the heat within the boiler. It is applied
without in any way altering the boiler or interfering with
present draught.

The Messrs. Howard, of Bedford, show their celebrated
Safety Boiler; and among the leading features of this boiler
are, safety (every boiler is tested to three times its working
pressure, and the bursting pressure of the tubes is at least
1500 lbs. per square inch), great simplicity of parts, facility
of repairs, and durability. In the Howard Safety Boiler
there are neither seams nor rivets, and no joint is exposed to
the direct action of the fire; the tubes are counterparts of
each other, and every part is made on the interchangeable
principle ; and it is more readily accessible, both internally
and externally, for thorough inspe¢tion and cleaning than
almost any other form of boiler—high pressure steam with
economy of fuel. With this boiler a pressure of I20 to
140 lbs. per square inch is more secure than ordinary boilers
working at 50 lbs., while experience has shown that on the
great question of the economy of fuel the hopes entertained
that the higher pressure of steam would, under proper

200 Fuel Economy. (April,

conditions, lead to an important saving of coal have been
realised.

A similar boiler is shown, and called the Safe and Sure
Boiler, bythe Patent Steam Boiler Company, of Birmingham.
They claim for their boilers absolute safety from explosion ;
this advantage is obtained by the subdivision of steam and
water in small tubes tested to a pressure of 500 Ibs. to the
square inch. If a tube should burst, the only result would
be a rush of steam and water into the furnace, a sudden
lowering of the steam pressure, and the extinction of the
fire. A boiler is often thrown aside as useless nine-tenths
of which is practically good, but from the remaining tenth
having failed the whole has to be rejected; with this boiler
that one-tenth could have been replaced by a new one in
perhaps less than two hours, when the whole would have
been as good asever. The nature and disposition of the
heating surface in this boiler are such as cannot fail to fully
utilise the heat applied, while the internal arrangements are
such as entirely prevent the escaping gases becoming much
above the temperature of the steam, and ensures, with an ordi-
nary amount of attention, perfect consumption of the smoke.

Mr. Stanley, of Sheffield, shows his Patent Furnace for
Smelting Ore. The advantages of these furnaces are, in
the first place, they effect a saving of from 25 to 30 per cent
in fuel. The use and expense of grate-bars are dispensed
with, as these furnaces have closed fire-places formed in
brickwork ; they make from 80 to go per cent less ash than
open fire-grate furnaces, the workmen have much less labour
in working these furnaces, and the heat is quicker and more
under the control of the furnace men.

Bailey and Co., of the Albion Works, Salford, make a
very fine show of Pyrometers, Hallam’s Ejectors, Oil Testers,
and other useful inventions. Bailey’s Patent Pyrometer is
used for indicating heat, saving coal, and promoting
uniformity of production in malt-kilns, ovens, and in other
places where a certain degree of heat is requisite. The

pyrometer for malt kilns is 4 feet long, and has an enamel —

dial 4 inches in diameter; the dial is indicated at 300—
black figures on a white ground. One of these pyrometers
has been tried at the Valley Mill, near Holyhead, and the
proprietor has tested it and found it very sensitive at any
change of temperature, enabling the man to keep his kiln at
the proper heat, which is very important in malt-kilns.
These pyrometers are also used by the Government depart-
ments for baking bread; it is also used for indicating the waste
heat in flues of works and locomotives, for indicating the

ee

1874.] Fuel Economy. 201

temperature of blast-furnaces, gas retorts, and other useful
purposes where high temperatures are used.

Bailey’s Oil Tester is a very ingenious instrument for
finding out the value of oils as lubricants; and if good oil
is used for lubricating, it reduces friction in the machinery,
and thus saves coal and wear'and tear. The tester may be
briefly described as a piece of 3-inch shaft and two brass
steps, upon which frictional pressure is obtained by weighted
levers ; a thermometer is fixed upon the machine, to denote
the temperature. One drop of oil is put on to a drum of
3 inches diameter, friction is applied, and the ‘“‘ life-time ” of
the oil (which is the technical term) is indicated by means
of a speed indicator, which indicates the number of revolu-
tions required to raise the temperature a given number of
degrees. The exact. money value of oil may be arrived at as
follows :—Suppose a certain quantity of No.1 oil on the
machine shows 200° by being driven 10,000 revolutions,
No. 2 oil shows 200° and 7500 revolutions, or 25 per cent
less value. In addition to this practical way of obtaining a
result, the machine may be driven to a higher temperature,
to see which oil produces the worst residue. In testing
various oils, a certain weight or measure must be taken;
the thermometer should always indicate the same tempera-
ture at starting. It is found that 200° F. is the best to try
all oils to, if their lubricating power is to be consumed, and
the machine should be always driven until that temperature
is indicated, and then immediately stopped ; the bearings of
the spindle should be well oiled, to prevent friction in the
wrong place; when a temperature.of 200° has been obtained
(the speed index showing zero at the start), it should then
be seen the number of revolutions taken to produce the
temperature. After testing the oil, it is directed that the
machine be stopped, and the oil is to remain on the machine,
and in twelve hours after it is to be tested again to see how
soon 200 can be obtained; the second experiment will
indicate which oil is the inferior on machinery when stopped.
The following is a short table of results on trying these
various kinds of oil :—

: Total Market Real value of
Quality of Temperature indicated Price the Oils,
Oil produced. Speed of per taking No. 1
Three Tests. gallon. asa standard.
s.d. Saas
Ide Tots! « 200 120,000 Ong 60
Rite esp ica) 3, (200 180,000 40 g 0
NS ser, oo 200 60,000 2 6 30

It will be seen that No. 2 oil will allow 50 per cent more

202 Fuel Economy. (April,

revolutions to be performed than No. 1, and must therefore
be worth 50 per cent more money.

Messrs. Johnson and Hobbs, of Manchester, exhibit a
model of a Patent Apparatus for the Condensation of Smoke,
Gases, &c. This apparatus is exceedingly simple and
inexpensive in its construction; it is on the paddle-wheel
principle, with an addition of projections on the blades to
produce a finely-divided spray of water, which falls through a
series of network composed of laths, brushwood, shingle, or
other material, and is so arranged as may seem best for
arresting the substances to be operated upon. The same
liquid may be used over and over again, until charged to any
extent that may be desired. The inventors declare that this
machine will be found more effective than the expensive
condensing towers now used for the purpose, as it produces
a powerful draught, which can be regulated at will, and the
solution can be made in the machine as concentrated as may
be required. The machine has been tried in condensing
ammonia, and has been found to succeed thoroughly; the
working parts of the apparatus can be arranged to resist the
action of hydrochloric and other powerful gases affecting
metal work.

Crossley Brothers, of Manchester, exhibit an Atmospheric
Gas Engine. This engine works as follows :—Gas and air,
mixed in such proportions as to give a mild explosive com-
pound, are admitted under a piston which slides air-tight in
a verticai cylinder open at the top. The compound is
ignited, explodes, and the explosion drives the piston
upwards. ‘The ignited gases, having increased in volume,
lose their heat; their pressure becomes less as the piston
rises, and when it has got to the top of the cylinder a partial
vacuum is formed, and the pressure of the atmosphere makes
the piston descend. The work thus done steadily by the
atmosphere during the return stroke of the piston yields the
driving power, which is transferred to the shaft by suitable
mechanism. This utilisation of the instantaneous power of
the explosion, by allowing the piston to fly up freely from it
without doing other work than emptying the cylinder of
air, is the basis of the economy and success of these
engines. The sudden energy of an explosion cannot be
economically applied to push a piston slowly along against
a load, as in the case of steam-engines; it is thus that
other gas engines have been superseded by this patent.
Some of the advantages of this engine, compared with
steam engines, are that it can be started at a moment’s

notice, and will at once give out its full power; thus no-

a

1874.! Fuel Economy. 203

time is lost in waiting to get up steam. The attendance
required is exceedingly small, averaging one hour per day
for a man, including cleaning, oiling, stopping, and starting.
The fuel has not to be got into the house, nor ashes to be
got out; gas is laid on, thus much trouble is saved. No
constant supply of water is required ; a quart a day suffices.
Gas at 4s. per thousand feet will feed the engine at one
penny an hour per horse-power. Gas can only be burnt in
exact proportion to the power required; this is controlled by
a governor. ‘These engines cannot be used for high horse-
power; from one to two horse-power is the most they can
be used for. From the many testimonials received, it seems
that the cost of gas is less than one penny per hour.

The show of fire-grates, kitchen ranges, various kinds of
coal savers, is very good, and perhaps the most complete in
the Exhibition. The grates, &c., are all in use in the third
annexé of the building, so that spectators can judge for
themselves as to the relative merits of the various inven-
tions. What would have made this show still more inte-
resting would have been to have given the weight of coal
consumed by each fire during the day to produce the desired
effect; as it is, one sees an interesting collection of machines
for saving fuel, but no experiments seem to have been per-
formed by competent judges to test the truth of each in-
ventor’s statements. There are various grates for utilising
the waste heat of the fire and causing it to warm air-
chambers, which warm air is carried to different rooms in
the house.

Shillito and Shorland exhibit patent grates and hot-air
boxes for extracting waste heat from every description of
grates and kitchen ranges, thereby effecting a saving of at
least 50 per cent in fuel, without at all interfering with the
general appearance of grates. One of their 30s. boxes can
be inserted behind register or sham register stoves now in
use, and could also be placed behind a kitchen fire without
taking down the range or grate, and, according to the
inventor’s statement, will raise temperature in excess of
external atmosphere from 10° to 20°, and discharge into
room or lobby 2000 cubic feet of warm air per hour. The
advantages of this fire-box grate over the ordinary grate are,
that it secures a supply of perfectly fresh, warm, pure air,
and diffuses it equally over the whole room, or rooms
requiring to be heated, the cold air admitted from the
outside being perfectly fresh, and warmed by passing over
the inside back of the grate. The objection to other hot-air
stoves, that they draw their supply from the already vitiated

204 Fuel Economy. (April,

air of the room, is obviated. When this grate is used in
dwelling-houses two rooms can be heated by the same fire—
the open fire serving for one room, and the heated fresh air
being thrown into the next. .

Thomas Whitwell exhibits a grate on a similar principle.
By his fire-place he injects warm air into the room at a tem-
perature between 65° and 115° F.

Rogerson and Co. show Corbitt’s Improved Economic
Warming and Ventilating Grate. It is simple in construc-
tion. The best points of the modern grate are preserved,
viz.—The cheerful open fire; large reflecting and radiating
surface ; reduced size of fire-box, with convex back, which
is composed of fire-brick, and, being a bad conductor, throws
the heat into the room; the draught-flue, opening into the
chimney, is regulated by Louvre valves, so that no waste
heat need pass up the chimney beyond the products of com-
bustion.

The most successful and ingenious fire-grate in the
Exhibition is the invention of the Rev. J. Wolstencroft,
and is called the Vacuum Draught. ‘The inventor says the
great difficulty is solved, viz., ‘“how to get a healthy,
cheerful fire, imparting a genial heat, with half the amount
of fuel commonly used.” We saw the grate in use, and
we must candidly admit it was the most cheerful and the
brightest fire in the place, but as to the amount of coal it
daily consumed we are unable to say. According to some
experiments which have been performed with it by James
D. Curtis, Commander Royal Navy, there is truth in the
inventor’s statement, that there is a great economy in the
consumption of fuel. Captain Curtis, of Brimpsfield,
Gloucester, experimented with the grate in his harness-
room from the 18th of August, 1873, to the 1st of Sep-
tember, 1873, using no other fire, burning slack coal
delivered for 24s. per ton, employing this fire daily for
cooking small things, such as boiling potatoes for the fowls,
&c., and after the daily use the fire was left to burn itself
out during the night; the cost of coal per day was 33d.
The front of the grate is continued down to the floor,
cutting off the supply of air from within the room ; by this
means an air chamber is formed under the grate, to which
the air is communicated from within or without the building,
bringing the draught under and directly through the fire-
bars. Ina fire-grate which has been fitted up in Manchester,
at the office of one of the Local Boards, the air-chamber
communicates with the main sewer, and draws its supply
from thence, thus, as it is supposed, ventilating the sewer,

1874.] Fuel Economy. 205

at the same time consuming the noxious sewer gases. Any
kind of fuel can be used, and very small coal can be burnt
as easily and with as good results as lumps; coke and
cinders may be burnt over and over again, until they become
as fine as sand. The ashes from the fire all drop through
the bottom of the grate into or through the air chamber,
consequently dust from the fire is greatly diminished in the
room; the draught may be regulated at pleasure with a
valve. The invention may be easily applied to many exist-
ing grates at the cost of a few shillings.

By the side of Wolstencroft’s fire-place was Kenyon’s
Patent Coal Saver, which consists of a perforated fire-brick
tile, to put into the grate and fill up the coal space, throwing
the hot coals to the front of the fire-place, while the back of
the fire is comparatively cold. It has the disadvantage of
presenting a very dull fire while it is carrying out its prin-
ciple of saving coal, presenting a great contrast to Wolsten-
croft’s; indeed one might almost think it was placed there
as a foil for his more successful competitor.

Crawshaw’s Household Coal Saver is a corrugated piece
of iron or clay placed behind an ordinary coal-fire. It
radiates the heat from the fire into the room, instead of
allowing so much waste heat to pass up the chimney.

Frisbie’s Patent Feeder and Grate is a most ingenious
arrangement for feeding a fire with coal from the bottom.
This feeder and grate provides a simple method of feeding
fuel up, from underneath the fire, into all descriptions of
furnaces, fuel-boxes, and fire-grates. By this principle of
feeding from below the fire there is no fresh consumption
of the fuel, the igniting of the fresh coal is a gradual
process, while at the same time a very intense heat is
obtained. ‘The hottest portion of the fire being constantly
at the top utilises the heat, and preserves the fire-bars from
being burnt out; the heat of the surface of the fire is not
abated by the supply of fresh fuel, and no cold air is
admitted to the furnace while feeding, thereby preserving a
perfectly uniform heat. By feeding from beneath, the coal
is pushed up and outwards equally from the centre of the
grate, and is evenly consumed, with scarcely any refuse
except fine ashes, which drop down through the grate-bars
without raking. From various testimonials which the
inventor has received, it seems that there is a great
Saving in the use of the coal; thus one firm says their
coal bill averaged £160 a month, but on introducing one
of these burners they only used that quantity in four
months.

VOL. IV. (N.S.) 2D

206 Fuel Economy. ‘April,

Folloms and Bate, of Manchester, exhibit a large collec-
tion of stoves and fire-grates. One of their novelties isa
Portable Water-Boiler, which consists of an upper and
lower chamber, and is so constructed that the upper
chamber is filled with cold water, and as the hot water is
drawn off from the lower, the cold water is allowed to fall
down through a small pipe, so that there is a constant
supply of warm water. It will boil 11 gallons in 20 minutes,
or three or four hundred persons can be supplied with hot
water for tea at a cost of 3 lbs. of coal.

There is a very good show of various kinds of peat and
patent fuel, with the necessary apparatus for condensing and
purifying peat.

Kidd’s process for carbonising peat consists of a large
chamber or drying-room connected with a boiler which
supplies superheated steam; from the boiler a steam-pipe
passes through the furnace, and from thence into the flue ;
the steam, in its passage over the boiler-fire, becomes super-
heated, and, together with the smoke, passes into the drying-
chamber; the peat, cut into pieces about the size of bricks,
is put into a framework which runs upon wheels, so that it
easily runs into the drying chamber, and is run out again ©
when finished, thus saving a great deal of labour. The
object of Kidd’s process is the collection of the heated gases
referred to in a closed chamber, where they may be usefully
employed in charring peat, or converting it into charcoal ;
an artificial draught is created by jets of superheated steam,
and the whole products of combustion from the furnace are
forced into and retained by the closed chamber. ‘The
chamber is filled with peat, which may be dried and charred
in less than forty-eight hours by the action of the furnace-
gases and superheated steam; the temperature of the
chamber soon rises to between 300° and 400° F., and remains
at some temperature between those limits. By charring
the peat at a low temperature the loss of hydrocarbons is
very small, the gases which are poured into the chamber
being for the most part non-supporters of combustion ;
consequently it is impossible for the peat to take fire during
the process of charring. The fuel used in the furnace which
supplies the gases and generates the steam is peat which
has been partially dried in the open air. It is estimated
that a ton of peat charcoal can be produced by this method
at a cost of 13s. 6d., which sum includes all charges for
interest on capital, royalties, and labour; raw peat at 3s.a
ton; that used for fuel, 4s. 6d. per ton. Peat thus prepared
produces a gas of high illuminating power, ranging between

1874.] Fuel Economy. ~ 207

20 and 22 candles, and 6000 and gooo feet per ton; the gas
is generated so quickly that three charges of peat can be
worked off to one of coal, thus effecting considerable
economy in the plant of gas works. The charcoal which
remains after the gas has been extracted is also much
more valuable than the ordinary coal-gas coke. There is,
no doubt, a large field open for commercial enterprise in
the manufacture of peat charcoal, owing to its freedom
from sulphur and its affinity for oxygen at a high tem-
perature. It is equal to ordinary charcoal for refining
iron, steel, and other metals. In France, this charcoal,
under the name of carbon voux, is largely used in the
manufacture of gunpowder; it has been used as.a fertiliser
also for filtering water and town sewage, and when com-
bined with a proper admixture of phosphate of lime it has
been found useful as a substitute for animal charcoal.

Henry Clayton and Son show some fine machinery for
preparing and forming blocks of condensed peat. One of
the difficulties in preparing peat for the market is to get rid
of the large amount of water which it contains, as sometimes
it is met with containing from 55 to 80 per cent. Of this, a
variable proportion is ‘‘loose, or free water,’’ much of which,
when present in the larger quantity, can be extracted by
means of drainage and squeezing ; the great bulk, however,
of the water is ‘“‘locked up,” confined in the rooty or fibrous
portion of the peat. So retentive is peat of this fixed water,
that no pressure, however powerful, can effect its expulsion
while the peat remains in its natural condition. The
objects which the Messrs. Clayton aim at are :—To get rid
of as much water as possible by draining and squeezing,
then to thoroughly cut up the fibrous or rooty portion,
releasing the great quantity of water and air which was
previously fast in the fibre, and reducing the whole to an
uniform state of pulp. Peat thus prepared will freely and
rapidly part with its moisture by natural evaporation, and
in so doing will consolidate itself, and thus acquire a density
which no pressure of the peat in its natural state could
produce, becoming very hard and compaét, and of a specific
gravity nearly equal to coal; in this state it is (unlike the
common prepared turfs) non-absorbent of water. The
patentees of the condensed peat say that it produces little
or no smoke, contains no sulphur, ignites more readily, and
diffuses the heat more generally and more widely than coal
itself, leaves no cinder and but little ash. To accomplish
these objects with peat direct from the bog, the peat is
filled (as dug) into squeezing-trucks, and during its convey-

208 Fuel Economy. (April,

ance from the bog to.the machine much of the “ free
water” is pressed from the raw peat by a simple and easy
means. From the trucks the peat is discharged into the
machine, which, in its a¢tion, continuously cuts up minutely
the fibrous portions of the peat, and produces a perfect ad-
mixture of the cut up fibre and rooty matter with the pulpous
portion, thereby utilising the whole mass of the bog and
entirely destroying its original character and natural spongy
nature. In its travel through the machine the material
further undergoes a moderate amount of pressure, and
acquires a density and form permitting it to be discharged
and deposited upon portable trays in blocks or briquettes of
convenient size, and thence conveyed by a simple and
labour-saving contrivance to the drying-sheds, where, after
three weeks’ drying (during average weather), the prepared
peat becomes hard, compact, marketable fuel. A trial of
condensed peat was made some time since for railway
engines on the Belfast and Northern Counties Railway, with
a view of testing its qualities as a fuel for locomotives. The
engineers who made the trial say: “In order carefully to
watch the power of the fuel in the generation of steam, we
rode on the engine from Carrick Junction to Ballymena, a
distance of twenty-seven miles. The pressure at starting was
too lbs. on the square inch; the commencement of the
journey was up an incline of about I in 80, 4 miles long, and
with double curves. While going up the incline the pres-
sure rose to I10 lbs., and afterwards to 120; the speed,
whenever this was permitted, was 40 miles per hour.”

Particulars of the above Locomotive Trial of Condensed

Peat Fuel.
Total quantity of fuelused . . 14 cwts. Iqr. 14 lbs.
Weight of train, peice Spear and
LENIGEr -. 5) “ys 70 tons.
Number of ‘catnages .':- 5 “.\..) a. mevele
MISS runs Sn 5. seinem eeye sb oe wanes
Time running . . 3 hrs. 9g mins.

Weight per mile used of peat fuel. 21°47 lbs.
Average pounds per mile for the last

three months, using Welsh and

Scotch coals at a ratio of 2 of

Welsh tot ‘of Scoteh <2; 4.)%. =: @5°a5unner
Average for the month of May last . 26°29 lbs.

The engineers conclude their report by saying :—“ Having
carefully noted all these faéts, we have no hesitation in
Saying that we consider the condensed peat in every way
well adapted as fuel for locomotive purposes.”

1874.] Fuel Economy. 209

A series of experiments have been made at the Com-
mercial Gas Works, London, on condensed peat, the results
of which are given below :—

Yield of One Ton of Coal.
Sperm corre-

Cubic feet Illuminating Cwts. Gasperton. sponding toGas
Description of Coal. of G Power in of equaltolbs.of of Boghead

aS: Sperm Candles. Coke. Sperm. Cannel No. 2,
equals 100.

Staffordshire . 2 .- << 7,100 12°42 13°5 302 13°6
Meabyshire . .° . « 7,000 II‘7I 17 305 13'7
iocheellys. . . . . 8,000 18°00 13 404 22°2
Derbyshire Cannel. . 8,500 20°60 15 600 27°0
Wigan Cannel . . . 10,000 20°00 13°25 686 30°9
Newcastle Cannel . . 9,800 25°00 13°25 840 37'°8
Lesmahago Cannel . 10,500 40°00 IO 1440 64°8
Boghead (No.1) . . 12,500 40°00 8 1713 aie

a (No.2) . ~- 13,000 48°00 6 2222 100°0

Yield of One Ton of Condensed Peat.

eeliadSire sts) ) «* 10;500 15°65 8 562 25°3
Prcavelcas.,- - - = 93240 18°75 8°75 594 26°7
SWEISHOtn ss. 2. I1,000 22°50 5] 849 38:2

The following, from a tabulated statement giving details of
the various peat enterprises actually now working, will afford
some interesting information on peat manufacture :—

Tons of Dry Relative

St Where Horse- Fuel per Ma- Cost Value

YEMoEe Working. Power. ae per per Ton. of to

a Lf Season. Coal.

ontreal, for
patees Canadian ( Grand Trunk 4000 6s. 6d. 5-6ths, or
Peat Company. | ey 84 p. ct.
= Engl

Boston ae Com { a he 4200 ‘Bs. Stance
Pci Pekin. New York. 13 3500 8s.togs. 84p. ct.

Haspalmoor. aoa Not ‘ 6 :
Colbermoor. Woks peel stated. 2B le

; ; Not Stated
Box’s. On trial. Detelares 4s. sa. —

Variable

Great Britain re e
Clayton and Son. and 6 3500 38.0d. = according
to 5s. to quality

Germany. oe

From the foregoing it will be seen that peat fuel possesses
a calorific power of five-sixths of coal, and can be produced
in Canada and the United States at from 6s. 6d. to gs. per
ton, where wages for labour are not lower than 7s. per day.

The Peat Coal and Charcoal Company make a show of
peat in all its stages, from the time it is taken from the bog
to the time it is compressed and carved, for they have some
pieces which have been cut into flowers and fruit, till it
looks like carved ebony. This Company has bought the
patent rights of M. Challeton de Brughat ; his process con-
sists in making peat coal having nearly the same density as
pit coal, and also he claims to have invented a better

210 Fuel Economy. (April,

method of preparing peat charcoal. The cost of this peat
coal at the manufactories may be taken at 8s. per ton for
small quantities, and 6s. to 6s. 6d. for large quantities.
1} tons of peat coal made by this process is reckoned to be
equal to r ton of best English coal; for stowage it will only ~
take, on an average, 20 per cent more room than ordinary
coal. This Company intend to establish their first manu-
factory on the borders of North Wales and Shropshire.
The peat on this land is of the best quality, averaging in
depth about 12 feet. A trial of this peat was made on the
Thames, on board the paddle-steamer Times, in the presence
of the Duke of Sutherland and a distinguished company.
The steamer ran from Beckton gas works to Greenwich in
twenty-five minutes with a strong head wind, slack water at
top of tide; and the quantity of uncompressed peat fuel
consumed in this twenty-five minutes’ run was about 210 lbs.,
maintaining a steady steam pressure of 50 lbs., without
smoke, and at all times a good clear fire. The experi-
menters state that for the generation of steam it requires
but a very moderate current of air, is absolutely smokeless,
and gets up steam equally quick as coal, and maintains it
with a less expenditure of fuel, does not injure the fire-bars,
and is in every respect much cleaner than coal or coke.
The South of Scotland Peat Fuel Company exhibit fine

samples of peat, which have been analysed and reported
upon by Mr. Heddle, Professor of Chemistry in the University
of St. Andrews. The composition of the dried fuel, on
analysis by combustion, is—

Gas sen st 6s Ska Pegs

Carbon Aree. a0 2) 2th ga ona!

PUSH op aj ce UAE em See ota
In its ordinary condition, however, it contains—

Wratertoat .- #4) «tet Hee
Gas No 60 oc okies ee ues
Carbon 2 act BL) as Ae ee:
ASD gS Seay aro ak coe

It was found that a sample kept for some days under
cover contained 16°4 per cent of moisture, and that samples
artificially dried regained upon exposure nearly the above
amount, so that it may be held to be impracticable to
improve the fuel in this respect; the fuel yields gas at the
rate of 7984 cubic feet per ton. When examined by Lewis
Thompson’s fuel test-apparatus, the calorific power of the
fuel was found to be—

In itsiusualstatess. <9 <) ap675
When dried .°°. 4:4 5940

1874.) Fuel Economy. 211

That is, one part of the fuel will boil off as steam above
4} times its own weight of water from 212°, and the dry
fuel about 6 times its own weight.

Mr. A. C. Pelly shows his patent peat fuel, which he con-
denses into solid balls, of the density of hard wood; the
peat balls, when manufactured ready for use, cost only about
5s. 6d. to 6s. per ton.

Professor Reynolds reports upon the process, which con-
sists in pulping the raw peat in a horizontal cylinder, within
which a shaft carrying a number of arms is made to rotate
rapidly, by steam or other power. The fibre is not only
broken in this machine, but, owing to a screw-like action of
the shaft, the peat pulp is forced through a circular opening,
and then appears as a cylinder of pasty material, which is
cut into short sections by very simple apparatus; the short
cylinders of pulp so obtained fall immediately into a truncated
cone, revolving rapidly. Here each piece is made to assume
a rough spherical form; these pieces are then dried. The
dry product of these simple operations appears in the form of
irregular balls; hence the term ball-peat. The following is
Professor Reynolds’s analysis of two samples of ball-peat :—

Hydrostatic moisture . . 15°12 14°87

BEA DO Maras ® sopra «fie ee, on (AOOR 47°22

PRLORENM co gic sc woe Ven OE 5°14

POU an kd. os. Sp eho te ook o 4 BOOS Bote

REHOREN se es ee, 0738 0°74

Pests ori o> ae pst oe ares OPE o°8r
Professor Reynolds says:—It is well known that the
heating effect practically obtained from ordinary rough turf
rarely exceeds 40 per cent of that afforded by Staffordshire
coal; this ball-peat possesses a heating value equivalent to
55 per cent of that of the class of coal mentioned, or, in
other words, to produce the heating effect obtainable from
1 ton of average Staffordshire coal it is necessary to burn
about 25 tons of ordinary turf, while 1°8 tons of ball-peat
would give the same amount of heat.

Reuben and Israel Levy exhibit ‘‘ Leigh’s” Patent Phoenix
Fuel, which consists of refuse from coal fires mixed with tar
or pitch, and made into balls. We cannot see the economy
of the process, as it leaves 75 per cent of ash; they claim
the novelty of using the ashes ad infinitum.

Radeke’s patent artificial fuel consists of small coal,
bound together in blocks by the aid of silica, both in solu-
tion and in a powdered state.

( 212 )

IV. AN INVESTIGATION OF THE NUMBER
OF CONSTITUENTS, ELEMENTS, AND MINORS
OF A DETERMINANT.

By Captain ALLAN CUNNINGHAM, R.E.,
Honorary Fellow of King’s College, London.

constituents, elements, and minors, in four classes of

determinants, viz., in ordinary, symmetric, skew
symmetric, and skew determinants. In calculations and
investigations relating to determinants it is often useful to
know these numbers independently of the actual formation
of the individual constituents, elements, and minors. The
investigation of these numbers will be found an interesting
exercise in the theory of combinations, and leads to some
remarkable symbolical relations.

The references are to Salmon’s “‘ Modern Higher Algebra,”
2nd edition. The type of a constituent of a determinant of
n rows will be written a?* and the corresponding first minor
as A,,., (as in Salmon, Art. 2.) All the constituents and all
the minors of determinants in the following problems are
supposed finite and unequal, except when expressly stated to
be otherwise. Without this limitation the investigations to
be given are not necessarily applicable.

A ae following paper is an investigation of the number of

I. Number of Constituents in a Determinant.

1. The number of constituents in an ordinary determinant
of n rows isin general (1.e. if the constituents be all unlike) n*.

2. In a symmetric determinant of m rows, the (1*~—%) con-
stituents not in the leading diagonal occur in pairs, and are
equivalent to only 3(”*—n) different constituents, making up
with the 2 different constituents in the leading diagonal a
total of 3(n?—n)+n=3n(n+1) different constituents im
general.

3. In askew determinant* the » constituents of the leading
diagonal are in general different, whilst the remaining (n*—n)
constituents occur in pairs equal i in magnitude, but of opposite
sign, so that there are im general—

n? different constituents, but only
4(n?—n)+n=3n(n+1) constituents of different magnitude.

* Saumon, Art. 37.
+ A distin&tive name would be convenient for this variety: the author
suggests ‘sub-determinant.”

~ ~ ue

1874.| Investigation of Determinants. 213

4. An important variety* of the above classes of determi-
nants is that in which the constituents of the leading diagonal
are all zero, in which case the above numbers are to be all
reduced by 7: thus the number of constituents will be :—

(x). In an ordinary determinant whose leading con-
stituents vanish, (”?—7).

(2). In a symmetric determinant whose leading con-
stituents vanish, $n(7—1).

(3). In a skew determinant whose leading constituents
vanish (this is styled a skew symmetric determi-
nantt), (”?—m) different constituents, but only
3n(n—1) of different magnitude.

II. Number of Elements in an Ordinary Determinant.

Let E, be the number of elements in an ordinary deter-
minant of ” rows.

Then a determinant of 7 rows oe be expressed i general
as a sum of different terms, viz., A= 3°" (a>,y. As,y), where
A,,, is the first minor of A STON ae to ay, and is
therefore itself a determinant of (n—1) rows, and contains
(by above notation) E,_, different elements! Moreover,
these E,,_; elements of each term of type (ap,y. Ap) in the
whole sum, which together make up A, are in general different
from all the elements in every other such term.

Hence, E,=1. Ex-:-
Similarly, E,-;=(#—1). E,-., and so on.
Hence, E,=2. E,-,="(n—1). Ey,-2=

| 2

=—~———" En-+ (x):

[n—r
= |. E,
SST CE BoA pe ete een ey ie eee me)
Since it is obvious that E, »=1, E,=1.

III. Number of Elements in an Ordinary Determinant whose
Leading Constituents Vanish.
dA , —_ A be Bila MAP AO, ? &

A, dappy dapp.dagg dapp. dagg. day Cos we
represent an ordinary determinant, and its successive first,
second, third, &c., leading minors, the leading constituents
(which are a type asp) being finite.

lees F lteg aac! leaeta ae: |e
Ts da pp da pp. da gq da pp. da gq. da yy C. «

» See note on preceding page.
+ SALMON, Art. 40.

VOL. IV. (N.S.) aE

214 Investigation of Determinants. (April,

represent the corresponding values of the preceding
quantities when the Jeading constituents are all zero.
Also let [E,] be the corresponding value of E,,

And let “C, be the number of combinations of n things
taken 7 together, so that—

sd 5 —

| 1 n

="Cy_re

| 7. |n-r

It is shown (Salmon, Art. 40) that in general—
dA d2A
= (A) + 24 aypeLaas |} + 34 aspen Exe = re

+34 AppUaqhyrrs crac mee
+ ose wt eo wt Gy-0ete © > Gan) eee

Hence, noting that the number of ways in which a con- ©
tinued product, as (a,;.42,43; . . + » Ar) of 7 constituents
can be formed from the 7 leading constituents (of type ap»)
is “C,, also that the number of elements in an vth minor of
type—
dra ]
day1.ddz2.da33 ..- + day)’
(being a determinant of (~—v) rows whose leading con-
stituents vanish), is by above notation [E,_,], also that by

the notation the number of elements in A is E,, and in [A]
is [E,], it results that—

En= [Ex] +°C,. [En-1] +%C,. [En-2] +... + . +°%C,. [En—o]
vere -2 [E, ] +7Cy-x LA ] +1.

= [Ey] +2. [En] feces) [Epaal +. to

| 7. | —9 Yr
, +t) TE] An [E:] +1... (4).

Now the numerical coefficients are the same as in the
expansion of the binomial (x+1)”, and the suffixes of [E]
are the same as the indices of x in that expansion; hence
modifying the notation with the interpretation—

[E]?= [E;], (s)
[E]*. (E] = [E]*#4= [Eps]
that is to say, making the suffixes of [E] follow the index
law, Equation (4) takes the following remarkably simple
symbolic form :—
B,=((E] 3)". wove a ee (6).

Further, this Equation being general for all (positive integral)
values of n—

er cabelas

-1874.] Investigation of Determinants. 215

B,.E,=((E] +1).((E] +1)"
=((B) +1)
= Epig eae wh Ce ics We Sela ee sin ee (7).

that is to say, the suffixes of E also follow the index law,
so that the notation may be further modified with the

interpretation—

(12) sed De gar ae oie ean ac Cor er (8).
Hence, from Eq. (6) and (8)—

GE)t= = (EP +1) sates ee (g).

and this Equation being general for all (positive integral)
values of n—

Bs hea, and je) = Bw <a. 3 (2O)s
These are symbolic relations between {E] and E of re-
markable simplicity, and lead to an explicit formula for
calculating [E,]. For—
LE,,] == [E] e—(K—1)".

n(n— |

= E,—*.E,-1+ =e a Bye oe +(- reo eer E,y-+t+

7
—— e
(eat

——.

4 (—1)t-2, 9). B+ (—1)"- 12. E,+(—1)" Ct).

IV. Number of Elements in a Determinant out of whose n
Leading Constituents only m are Finite.

Generalise the notation of Problem III. as follows :—

mera), [A’], [A], .-» = fA”) represent the values of
A (an ordinary determinant with finite constituents), when
out of its leading constituents (of type @,,) there are re-
Spectively none, one, two, &c.,... . m fintie, and the
remainder zero.

Memes), (,), [E's],> . . [E"] represent the corres-
ponding values of E,: by this notation [E”] =E,.

Then, by the same reasoning as in Problem III., and
noting (in addition) that all terms involving the continued
product of more than m leading constituents vanish
necessarily in the case of the determinant [A”], it follows
that—

[A”] = [A] +35 an-Laa,, |} +3 1p i eosge all, cat

dma )
$Y (i223 le oe dnm)-| dagedice don ae a= ||, S (12).

216 Investigation of Determinants. (April,

* (E*) = [En] +”Cx. [En-1] +C2. [En—2] +. $C, [En-2] +
Pe og ape Ie bore mal + per Pa
um=2) + PByeg Pe +S [En-r) +

am er ea = Lees a” he's (13).

Next, changing every term [E,] into its symbolic equiva-
lent [E}?, see Eq. (5), [E]”-” is seen to be a factor in every
term of series (13), which may, therefore, be symbolically
expressed—

=[E,] +--[E,-1+7—

Rae = (aes . { [E] ep , (14).
= (Eel . Eni (See Eq. 6).
Hence also, by changing m into (1—m)—
PB TD Ul Oe 0 Ga
= [Bml. Ey (See grb):

Again changing [E] into its equivalent (E—1), by Eq. (10),
and interpreting the result by Eq. (8).

[Ee] Lee Dee,
=E,— 2 By S B, a. . +(—1). ap En-rt

: ee cae n—m= ° (16).
Formule (13) and (16) furnish the means of calculating
[E;'] or (E,”] in terms of [E] or E respectively. The
former is preferable if m <2, and the latter if m > +2.

The following particular instances of these expansions
may be recorded for reference :—

[Ee] — [En] cir [En- 1} 3 ?

[EA] =E,—En-,:
[E”,] = [E,) Te [En-:] is [En,-al 3

Boa = En — 2E na i En-2
[E,,] = (E,] +3 [En-1] +3 [En-2] + [En-s];

a =En—3Es-1+3En-2- | 3]

The following relations between successive values of [E, ]

and also [E’’"”] might be obtained by induction from the
above equations, viz., that—

[E] = (EY) + (ee
(18)

(17).

ag = (Ea ni £: [Br"4

n n—-t

J

1874.] Investigation of Determinants. 217

but are more readily obtained in a general manner by
symbolic work, thus—

[E, J ot [Ea = [En—m41) “Em1+ [En—m] -Em—1 by Eq. (14).
= [Exn-m]. En-1 { [E] +1} by Eq. (5).
=[(F,2nleBm— [E,] bysEq. (no. 7,.and x4).

San - noes = Bigerl-Epmta— Pen denen DY G5).

7 [Em-—xz] i j—-m.(E —1) by Eq. Cae
= [Ey] En-m= (Bey by Eq. (Io, 5» & I5)-

V. Addendum to Problems (II1.) and (IV.)

The expressions (11) and (16) for [E,] and [E/~”] in
terms of E obtained by a symbolic inversion of the formule
(4) and (13) previously obtained for E, and [E”’] in terms of

[E,] may also be obtained by algebraic inversion of the
same formule, but the process is very tedious. They may
' also be obtained directly from the properties of determinants
by establishing expressions for [A] and [A”~”] in terms of A
inverse to the expressions (3) and (12) used in the text.

The required expressions are easily seen to be—
dA d2A
[A] =A- %{49p-aa,,} + 3 {496 Va0- Ga aay |

ep
dA
pda gg Aa,} t

Pe es eae (= 1)%. ads, 4. = Gan)» (TQ)

a | =a-3 {andes} +3 ep |

{4 pp%aqrr- da

pp 4% aq
dma

)
dayx. ddzg. da33.-- damm | (20).

ae +(- 1)". 5 { AirF2a%33 ©» Ainme

Equations (11) and (16) may be derived from Eq. (19) and
(20) respectively by considerations precisely similar to those
used in obtaining Eq. (4) and (13) from Eq. (3) and (12)
respectively in the text.

The relations established in Problems (III.) and (IV.)
between E,, [E,], and [E;,] are evidently derived in a
manner which shows them to be generally true of all determi-
nants whatever which are related to one another similarly to
those styled A, [A], [A”], @.¢., differing only in their leading
constituents (those of A being all finite, those of [A] all zero,
those. of [A”] being m finite, and the rest zero).

218 Investigation of Determinants. (April,

VI. Application to Ordinary Determinants.

Substituting Es = | 4, (Eq. 2) into Eq. (11), there results—

J = [#-{1-7e+75—Te+ -- wah
(—a)t* heh
be Mage ae [u—1 + iz (21)

A relation between three successive values of [E,] may
be thus found by Eq. (21)—

[toa ae [En—al = [m1 (Qc x + |n-2 n—2. x 2
=\"—I. ae +{@—-n-41}. ln — noes

*(1—1).{ [En—s] + [En—2l } =(—2)*"*-@—-)+ is =

=|n. (= ne (- 1)" +S%pie 2 :

| ~—1 IE
= |." (=1)*
|
= [E,],.. by Eq: (20)... teem
This relation (22) between three successive values of [E,]
may also be thus obtained directly :—
Since the leading constituents of [A] are all zero (by
definition)—

[A] =3. Bay cal Pad Glee a . (23).

in which equation y,z take all positive integral values (except
d{A].
equal values) fromito”. Now ata) is easily seen to be a
‘yz

determinant of (n—1) rows containing (”—2) of the leading
(evanescent) constituents of the original determinant [A],
and no two of these in the same row or column. ‘These
(n—2) constituents may by Bees of order of rows or

columns of the determinant ie be all brought into its
j2

leading diagonal without altering its mwmerical value (the

only alteration being of sign). It follows that the number ~

A
of elements in os a4 is the same as in a determinant of (7—1)

rows with only one finite sa constituent, which number
(by notation of Problem IV.) is [E’,-:].

1874.] Investigation of Determinants. 219

Further, the number of terms in the sum in Result (23)
is clearly the same as the number of constituents of type
Ayz in [A], t.e. (n?—n), see par. 4, Problem I.

Hence, since [E,] is (by the notation) the number of
elements in [A], it follows from (23) that—

[E,] = . (n? —n). [E’,-1]

=(n—1).{ [E,-:] + [E,_,] }, by Eq. (17) . . (22).
Thus, the value of [E,] may be calculated for successive
values of » by formula (22) from the known values of
‘{E,], [E.], &c., or may be directly calculated from the
series (21).
It will be useful to record a few values of [E,] for
reference, thus—
[E,] =0, [E,] = 1p [E,] = Zoe [F,] =9Q, [E,] = 44,
[E«] =265, [E,] =1854, [Es] =14,833,/- - (24).
[E,] = 133,496, [Exo] = 1,334,961.
Corollary. Substituting for [E,] from Eq. (21) into
Eq. (4) and (2), and separating the symbols of operation
and quantity—

[a=En= | *{20+77.20 +7230 +e (oe
oa eee sa aeeee ed
from which may be deducted Hees sues
Me de (OF arash

[= tna La www 0 (25)

?

It is easy to see that all the terms of the series (21) for
[E,] are even integers except the two last, which are
(—1)""? (n—1), so that [E,] will be an integer, and odd or
even according as 7 is even or odd.

VII. Number of Elements which are Products of n+-2 Pairs of
Conjugate Constituents in a Determinant whose Leading
Constituents Vanish.

This problem is a preliminary to the problem of finding
the number of elements in a symmetric determinant.

By ‘conjugate constituents”? are meant pairs of type
Ba xy «

The type of element in question is—

{ (Apq.qp)+ (Ars.Asr) + oe os (Ayz. Ary.) }
containing »+2 products of pairs of conjugate constituents,
such as (@yz, az). This element may be separated into two
conjugate factors, ViZ. (@pq.rs- « + + Gyz)» (Aqp. sre « 2° » Apy)

220 Investigation of Determinants. (April,

either of which involves the other, and each of which is the
product of +2 constituents involving all the suffixes without
repetition. Hence the number of such elements is the same
as the number of ways in which a product of +2 con-
stituents can be formed involving all the n suffixes without
repetition.

Let S, be the number of produé¢ts containing suffixes
without repetition. ;

Now the number of constituents containing any particular
suffix p is clearly (7—1), for these constituents are of type
A»sy, Where y has every value from 1 to , excepting p. Also
for every such constituent as as, there are (7—2) suffixes

a: a n
remaining to form the remaining (4-1) constituents

required to form the complete product of +2 constituents.
Further, these (7—2) suffixes can be arranged into the

required product of (7-1) constituents of the requisite

type in S,-2 ways (by preceding notation).
Hence 8S, =(”—1). Sy_2.
Similarly S,-2=(”—3).S,-,, and so on.
Hence S, = (n—1).S,-2= ("—1).(u—3)Sn-4= «se
= (n—1).(n—3).(u—5) . . » 7.5-3.92 + - | (26)
= ("=—1).(7—3).(u—5) . « 27.543.L. nee
since obviously when n=2, there is only one pair of con-
jugate constituents (viz., a,2,42;), so that S,=1

_S _ n(n—1)(n—2)(n—3)(n—4) WH nice Mon ee
x "y nm. (n—2) (m—4). 5 = sie 3 6.4.2
n : : -
=——. , where » is an even integer. > + (27).
n\n
22.)5

It is obvious that, if 2 be an odd number, the proposed
product of n+2 pairs of conjugate constituents could not be
formed, z.e. that 10 elements exist of type proposed.

-, S, =0, when # is an odd integer ss’. Sy ee (28).
A few values of S, may be recorded for reference, and note
that S, is always an odd integer (when » is even), being
itself the product of odd integers, Eq. (26).

So=1, S2=1, S,=3, Ss=15, Sg=105, Sr= 945 - « » (20)

VIII. Number of Elements in a Symmetric Determinant.

Modify the preceding notation in capital letters for ordinary
determinants by using the corresponding small letters with
like meanings for symmetric determinants.

1874.] Investigation of Determinants. 221

Thus.A, [A], [A”], E,,[E,],[E”] become—

6, [8] , (8"], ¢,, [e,], [1 -
All the relations between E,,[E,],[E),] established in

Problems (III.) and (IV.) obtain also between ¢,, [e,], [e, J,
having been established in a general manner, as properties
common to all determinants.

The number of elements [e,] in the symmetric deter-
minant [6], whose leading constituents vanish, will first be
investigated.

Number of Elements in a Symmetric Determinant whose Leading
Constituents are Zero.

In the ordinary determinant [A] whose leading constituents
vanish, the elements may be divided into two classes :—

(z), Of type {(apq.@ 4). (Grsasr,) - +» (@yz4zy)} Consisting
of the product of +2 pairs of conjugate constituents (such
aS (dyza:,) only. This number has been investigated in
Problem (VII.), and denoted by S,..

(2). Of type—

{(Apq.%qp)-(ArsMsy) « « « (yz. Azy) | X {Aye Agn.ani. » + + Amz},
consisting of the product of + pairs of conjugate constituents
(such as ayz. @zy), and (1 — 27) other constituents (containing
no conjugate pair; that is to say, consisting in part at least
of the product of constituents containing o conjugate pair.
The number of this type is clearly {[{E,]—S,},[E,]
being (by the notation) the whole number of elements in the
determinant [A].

In the corresponding symmetric determinant [6], in which
(by definition) a,,=a.,, these classes become—

Bet type: {(ap7.Grs:. «.- + . @y;}*, each element being
the square of the product of +2 constituents, without
repetition of any suffix. Also the number of these is clearly
the same, viz., S, as in the corresponding ordinary deter-
minant [A].

(2). Of type{as.a,s. . . . Ay, | x {Ajg.dghAni. + + + Ang}
consisting of the product of the square of the product of 7
constituents, without repetition of any suffix, and the product
of (n—z2r), other constituents containing no conjugate pair,
which therefore involves the remaining (n—2r) suffixes in a
cyclic change, 7.¢., each occurring twice.

Now in.the ordinary determinant [A], elements of this
type (2) occur in pairs, 7.e., for every product of a particular
set of conjugate constituents, as {(a pq Aap) -(ArsQsy,) + (ays, Gxy)},

VOL. IV. (N.S.) 2F

222 Investigation of Determinants. (April,

there is a pair of conjugate products of (n—2r) other con-
stituents, viz. {ajeMgn ni,» ++ + Amp} and {aym, «+ » Gin. Une. Aep.} y
so that the type of the sum of a pair of such conjugate
elements is { (@9.aqp).(@ys Asy ) + « (AyzAzy.)} X [ {Ape Agn.Ani + - Amst
+ {Ajn- + Gin Ang Meg |), which pair reduces in the symmetric
determinant [¢] to a single element of type—
Z{Apg.Ayse sree Ay: |. (Ajg Agh.Ani.» + +++ Ams.)
since by definition ay, =a.). “The number of elements of this

type in the symmetric determinant [3] is therefore one-half
that in the ordinary determinant [A], 7.c.is }{ [E,}{—Sn },

Adding the number of both classes together, there results—

[Ey ] =S, +2 { [E,]—S, } = { [Bal +S, } o. ota o ee a ae (30).
substituting for [E,] and S, from formule (21), (27), (28), t
(én) =z [En] = e. an when 1 is odd

(31).

Js 8

2 \3

os ee ere :

Pikes (LA et Ses Cae 5 gf when n is even
Also, since [E,] is known to be an even integer when is odd,
and an odd integer when % is even (see Problem VI.), and
since also S,, is an odd integer when » is even, it is easily
seen from (31) that [e,] is always an integer (as of course it
should be).

A relation between three successive values of [e,] may be
deduced from that between three successive values of [E,],
see Eq. (22)—

Thus [E,] =(#—1).{ [E,—-1] + [E,-2] }
sro 2? [en] — 3. (n—1).{2 [én—x] +

+2 [én—2] —S,-:—Sn-2} ’ by Eq. (30).
And when is odd—

|n—1
,—0; cee =

u—I,
2

—— Sy-2=0, by (27), (28).

And when 1 is even S,, =(n—1). S,—2) Sn-1=0, by (26), (28).
+ [én] = (—1).{ [¢n—1] + [€n—2] } = -Sn—s
when# is odd ./) "7, “21 3. saa 2).
[én] = (n—1).{ [en—s] + [én—2] } G
when 1” is even

Thus the value of [e,] may be calculated for successive .

1874.] Investigation of Determinants. 223

values of ” by formula (32), from the known values of [e;],

fe], &c., or may be directly calculated from formule (31).

\

It will be useful to record a few values of [e,] for reference—
[20] =I, [e,] =o[e,] =1, [e,] =, [e,] =6, [es] =22,

[és] =140, [e,] =927, [es] = 7469, [e,] =66,748,+..- - (33).
[ero] = 667,953

IX. Numbers of Elements in a Symmetric Determinant.

This may easily be calculated from the known number
[én] of elements in the symmetric determinant [6], whose
leading constituents are zero, by help of the relation between
eand [e] (see Eq. 6).

Thus é, =(1+ [e] )”

_— id
=1+ = [e] + enor eee Eel

+ = [e.-1] + [én] +--+ (34)-
It will be useful to record a few values of e, for reference,
thus—

=I, =I, &,=2, 6,=5, e,=17, €;= 73, &=398, )
¢, = 2636, €g= 20,542, €s= 182,750, €,,-=1,819,148 J

~ » (35).

X. Number of Elements in a Symmetrical Determinant, out of
whose Leading Constituents only m are Fimte.

This may be easily calculated, either directly from the
relations (13) and (16), or for successive values of ~ from
the relations (18) which have established for all deter-
minants. Thus changing E to e—

ie fe, | Fd

m

ag | 7. | m—r* -[én-r] +. +7. [En — m+xl aa [en pleas (36).

m( m—

— (J2)5 hm

=€y SN ee eee spe atee+ [7 Tr [mar -€n-rt -

m

+(-1)"- hs » Cn- m+r+(—I)" Cn—m 2(37)-

(P) = 61 + ME), and (5) = fe) — IT. . G8).
On account of the great use of symmetric determinants
in modern geometry, it will be useful to record the values
of [e"] in a few cases. Thus, observing that fe. | = (eo);

and that [e” ] = [e ], (by notation) —

224 Investigation of Determinants. (April,

Table of Values of [c"].....-(39)-

m

d fe) “h li ili iv v vi. vii vili ix x
oO I

I ° I

2 I I 2

3 I 2 3 5

4 6 7 9 12 17

5 22 28 35 44 56 73

6 140 162 Igo 225 269 325 308

7h 927 1067 1229 1419 1644 1913 2238 2636

8 7469| 8396 9463| xo692| 12111 13755 15668 17996} 20542

9 || 66748] 74217] 82613] 92076)102768| 114879] 128634] 144302] 162208 182750

10 || 667953 | 734701 | 808918 | 891531 | 983607 | 1086375 | 1201254 | 1329888 | 1474190 1636398 | 1819184

XI. Number of Elements.in a Skew Symmetric Determinant.

Denote the number of elements in a skew symmetric deter-
minant of 7 rows by [e, ], the brackets being used to preserve

the analogy with previous notation for determinants whose ©

leading constituents are zero.

It is shown (Salmon, Art. 37) that every skew symmetric
determinant of odd order vanishes; the number of its ele-
ments is therefore zero.

It is shown (Salmon, Art. 38, 39) that every skew sym-
metric determinant of even order is a perfect square, and
may be expressed by {3(+ap5q.drs...+Gyz)}?, 4.€., by the

square of the sum of terms of type Gea . Ars.» bys), CACHE

of which is the product of ~+2 constituents, involving all
the suffixes without repetition. It has been shown (Problem
VII.), that the number (S,) of such produéts in a deter-
minant whose leading constituents vanish (as is the case in
a skew symmetric determinant, see Salmon, Art. 37) is

n
Sn = [n+(2?- zs
Also, since the determinant is the square of S, different
terms, it follows that the number of its elements [e, ] is the
same as the number of terms in the expanded square of the
sum of S, quantities.

ies (number of combinations of
let eis +} S, things two together).
=S, +3458, .(S, —1)
a Sn . (Sn + I),

- nN f
|~.(|"+2?.) >) \ when # is even... . (40).

gti. ( | -)*

And [e, ] =o, when » is odd, (v. supra).... (41).

1874.] Investigation of Determinants. 225

Eq. (40) shows that [«, ] is always an integer (as it should
be). It will be useful to record a few values of [e,] for
reference. Thus—

[6] =I, le] =1, [e,] =6, [e6] =120, [eg] eae «e(42)
[ero] = 446,985 J ~~

XII. Number of Elements in a Skew Determinant.

Denote the number of elements in a skew determinant of
nm rows bys. Then, since a skew symmetric determinant
is a skew determinant whose leading constituents are zero,
‘the relation between them is the same as between [A] and
A, so that the relations between [«, ] and «, will be the same
as those between [E,, ] and E, demonstrated under Problems
(III.) and (IV.) as common to all determinants. Thus, the
values of «, may be calculated from Eq. (6), viz.:—
& =(I+ [e]”)

n(n —1) | 2

E+ 5. lel tog - lel +++ +7ppnce- eI +---

+* [én—z] + len J..ee (43).
A few values of «, may be recorded for reference—
Si, G1, &,=2, €,=4, &=13, &=41, &= 220,
&,= 1072, &= 9374, &= 60,968, &,.= 723,966 j sorte
It is also seen that if [e”] denote the number of elements
in a skew determinant out of whose leading constituents
only m are finite, then changing E in Problem (IV.) into ¢,
all the relations demonstrated under Problem (IV.) between
E,, [E,], and [E;"] are true between «,, [e,], and [e,], so
that [e] may be calculated from the known ¢,, [e,] by the
formule of Problem (IV.).

XIII. Number of Minors in a Determinant.

By definition, a pth minor is formed by erasing £ rows and
p columns from the original, so that evidently :—

A pth minor is a determinant of (n—f) rows and ae
A (n—p)th minor is a determinant of £ rows and columns

Let ”M, be the number of pth minors that can be formed
from a determinant of » rows. Then”M,-_» is the number
of (~—p)th minors.

It is obvious that, in this notation, the minor of zero
order (6=0) being the original determinant itself, and the
minors of mth order being zero—

*“M, =I, and”M, =1
in all determinants (which are finite).... (45).

226 Investigation of Determinants. (April,

Now "C, being the number of combinations of things
taken y together (as in Problem III.), it is clear that “C;, is
the number of ways in which p rows can be selected out of
nm rows, also that “Cy, is the number of ways in which
fp columns can be selected out of ~ columns. But “My, is
evidently the number of ways in which any p rows and any
p columns can be selected simultaneously (for erasion) from
the m rows and 2 columns in the determinant.

nN nN n n | a
nt es IG ec, Ss 2. 1(46).
Eq. (46) shows that, as is also evident from the reasoning
itself—
"M, LS "Nig 4; a pa be uote Cie ve ke "pum (47).

From the preceding reasoning, it may also be inferred
that result (47) is a property common to all determinants
whose minors are all finite (except in certain cases when

these numbers ”M, ,”M,-» are unequally reduced, in conse-
quence of the constituents being so related as to produce
equality among some of the minors).

As a particular case of Eq. (47), "M:= *Mu-z, 1.¢., “ The
first minors are the same in number as the constituents
(these being actually the »—1th minors).”

XIV. Number of Minors in a Symmetric Determinant.

In symmetric determinants it is clear that there is only one
way in which a particular leading minor (which is itself
also a symmetric determinant) can be selected, but that any
other minor can always be selected in two ways, e.g., the
same (non-leading) fth minor may be formed either by
omitting a certain set of # rows and / columns from the
original determinant, or by omitting the conjugate set of
p columns and f rows. This amounts to saying that the
non-leading minors occur in pairs of equal magnitude.

Now the number of leading pth minors being those minors
which contain (n—f) leading constituents of the original
determinants in their own leading diagonals, is clearly equal
to the number of ways in which (7—/) constituents can be
selected from the whole 7 leading constituents, 7.e., is equal
to CO or is 65 °

Also, the number of non-leading pth minors would in an ordi-
nary determinant be (Problem XIII.) {("C,)? —"C, }, which

reduces in a symmetric determinant to } {("C, )* —"C, } for

1874.] - Investigation of Determinants. 227

the reasons above. Hence the whole number of fth
minors is—
"Mp = "Cp +41("Cp)° —("Cp )}
eC, ("C, +1), which is clearly an integer. || (48),
mee ele: Laae
a2 Cb: p=?)
Since “C; = "C,_;, therefore in symmetric determinants—
Siren Mig pert ta a a aes (49).

On account of the great use of symmetric determinants
in modern geometry, it will be useful to record some values
of "M, for reference.
N.B. In general "M,=1= "M,,

"M,=3n(n+1)= "My-: - (50).
"M,=4n.(1—1) (1 —n+2)="M

;

Nu—2

Walses, Gf Mipsis ans or suls (51).

Value of p.

n.
oO. I 2. 3. 4. 5. 6. bie 8. g. |10.

I I I
2 I 3 I
3 I 6 6 I
4 re, |. ro 2E Io I
5 rT} 15 55 55 15 I
6 eo I20 | 210 120 21 I
b E28 231 630 630 231 28 I
8 I | 36 | 406 | 1596 2485 1596 406 36 I
9 I | 45 666 | 3570 8001 8001 3570 666 45 I
Io Hee 55 |) L035) | 7260 | 22755 31878 22155 | 7260 | 1035 | 55

XV. Number of Minors in a Skew Symmetric Determinant.

Note that all leading minors are themselves skew sym-
metric determinants, so that all leading minors containing
an odd number of rows vanish (Salmon, Art. 38). Nowa
pth minor contains (n—p) rows, and the number of leading
pth minors in a symmetric determinant is in general

2C, = iB aE (see Problem XIV.). Hence, in a skew sym-

metric ee the number of leading pth minors is Zero,
or "Cy according as (1—) is odd or even. And the number
of non-leading pth minors will be the same as in a symmetric
determinant in general, viz., }.{("C;)?— "C,}. Hence,
in a skew symmetric determinant—

228 Investigation of Determinants. (April,

n n n |” |n— |é.|n-p
Mp a re ( OF ie 8 he . “([p- =p)? ?
when (n—f) is odd
3 bs . [n |n+|p.|n-p - (52).
My =3- Cp. (Cp += + Cp [ap

when (”—/) is even J

These quantities are evidently both integers (as they
should be). Eq. (47) is true of this class of determinants
only when f and (m—) are both odd or both even, which
cannot occur when 7 is odd, but always happens when » is
even. Thus—

"My = "Mu-», when is even...... (53).

The following relation obtains between two successive
values of "M,, the higher value of m being an even number; so
that (n—p) =(n—1), an odd number, and (n—1—4) = (n—2),
an even number.

2. "M, =}. (n—1) =} (n—1). (n—1 +n) ="""M,, by (52),
n being even .... (54).

Eq. (52) shows that, 7m general, Eq. (45) is true of this
class of determinants only when finite, 7z.¢c., only when of
even order, thus—

"M, =o= "M,, when is odd. |
"M, =1= °M,,, when 1 is even.

It will be useful to record a few values of "My, for this
class of determinant. Thus—

Viabuks:0f My «caja oneie (56).
Value of p.

im.

fo) I 2 3 4 5 6 7 8 g. |r0
I || o oO
2-|| I I I
3 || o 6 3 oO
4 I 6 21 6 I
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1874.} ( 229 )
NOTICES .OF BOOKS:

Darwinism and Design; or Creation by Evolution. By GrorGE
St. Crarr, F.G.S., M.A.1.A., &c. London: Hodder and
Stoughton. 1873.

WE have here yet another attempt at a reconciliation of theology

with science; but it is one which differs in many respects from

all that have gone before it. The doctrine of evolution, as ex-
plained by Spencer and Darwin, is accepted in its entirety, and
no objection is made to the most extreme consequences which
those authors deduce from it; but it is argued with much force
and ingenuity that design, and the constant action of a Supreme

Ruler, is not thereby rendered inconceivable or unnecessary.

A condensed but exceedingly accurate and well-written account of

the most recent views of evolution is given in the first part of

the volume; and this is a great merit, seeing how incapable
most theological writers are of avoiding either positive misrepre-
sentation or a partial and one-sided statement of the teachings
of evolutionists. The theological treatment of the question is,
however, somewhat peculiar and heterodox, and we fear will not
meet with a favourable acceptance from the religious world;
and this may render Mr. St. Clair’s book less generally useful in
reconciling the modern Christian mind to the teachings of

Darwin than it might otherwise have been. A short account of

the author’s mode of treating the subject, and of the peculiarities

above referred to, may not be uninteresting.

Throughout the book we meet with expressions and arguments
which show us that the Deity or Supreme Ruler spoken of by the
author is not the being to whom those terms are applied either
in philosophy or religion. It is not the “Absolute” of the
philosophers; it is not the ‘‘Almighty” and ‘‘ Omnipresent”’
deity of the Christian; but it is a being subject, like ourselves,
to the laws of matter and motion,—having to recognise the
“nature of things,” but having infinite knowledge which enables
him to make use of the universe and its ‘‘necessary laws” so as
to work out his own purposes. This view, which appears to us
an impossible or at least an imperfect one, seems to have been
adopted owing to the supposed ‘inconceivability”’ of the creation
of matter out of nothing—an inconceivability which vanishes to
any one who can thoroughly grasp the conception of matter as
being essentially a complex set of forces and nothing else. To
hold that these forces are eternal and self-existent, and that they
produce by their varied interactions all the forms of dead matter,
while an omniscient mind—equally eternal and self-existent—
finds itself face to face with this matter and these forces which
it can neither destroy nor originate, but only guide, is surely to

VOL. IV. (N.S.) 2G

230 Notices of Books. (April,

multiply difficulties. That the ‘forces” which we know as
‘‘matter” are in some way dependent on the supreme mind
appears to us the only alternative to pure materialism; and this
view renders it perfectly conceivable that ‘‘matter” may ‘be
made out of nothing,” or may be again resolved into nothing by
the withdrawal of the mental action which is the sole cause of
its existence. But if we conceive the material universe to be
thus the product of the supreme mind, we may equally believe
that there is a mental or spiritual universe, of which we our-
selves form a part, and that the former is the means by which
the latter is developed with the greatest capacity for happiness
and eternal progress. Now Mr. St. Clair’s deity is just sucha
being as we might suppose to be the highest in our material
universe, and who might be charged with utilising to the utmost
the powers of that universe in developing mind. He would
“not violate natural law, but work by means of it,” and his work
would be liable to those ‘incidental results” often temporarily
painful, injurious, or useless, which are such a stumbling-block
to the usual ideas of divine government. The slow process of
development—first of systems, then of worlds, then of matter
into complex forms and qualities, and lastly, of organisation and
life—has probably its own high uses, of which we can form no
adequate conception. It may help the development of higher
intelligences than ourselves; it may be the only mode by which
multiplied forms of those higher intelligences can be produced.
At all events, it is the system of nature; and it is hardly likely
that any other possible system would be more intelligible to
beings like ourselves—produced by it and still forming part of it.

Having thus indicated how we think Mr. St. Clair’s theory may
be made more consistent and more comprehensive, we proceed
to give a few examples of his style of illustration and mode of
reasoning. ‘The argument against design from the existence of

:

fi

rudimentary organs or traces of structures that were useful only —

in ancestral forms, is answered by supposing a town, in which
one of the main water-pipes goes half a mile into the country,
and then bends back again with various windings for no useful
purpose. ‘ We ask where is the wisdom of carrying the water
through this mile of pipe when it might go by the short cut?
Why waste the tubing, and waste the time, and do what has to
be undone immediately, in sending the stream to a point from
which there is no course but to return? On the supposition that
the town was originally built as it now stands, every street and
square having the position they now have, and not a house more
or less—our objection is valid. But if we learn that the diverging
bend of pipe follows the route of streets which formerly existed,
and that although the shorter cut would now seem better, yet it
would cost more to take up the old pipes from the long route and
lay down pipes on the short route than could possibly be gained
by the process, we see the wisdom of leaving the arrangement

1874.] Notices of Books. 231

as itis; and we read inthe existence of the bend of opipe a page
of the past history of the town.’

To the objection as to the existence of carnivorous animals in
all ages of the earth’s history, it is well replied that evolution
shows struggle and death to be absolutely necessary to advance-
ment and to render possible the eventual birth and perfecting of
man. It is also very forcibly argued that there are many direct
marks of beneficence in nature. So far as we know, there was
no absolute need for life to appear at all on the earth; or, when it
appeared, for it ever to have advanced beyond the lower forms ;
or for the distinction of male and female ever to have arisen;
or for the eye to have the capacity of distinguishing sensations
of colour as distinct from light and shade; or for the ear to be
attuned so admirably to vibrations of the atmosphere as to
render music possible; or for the taste to be capable of delight-
ing in such an endless variety of savours. When we look at the
whole range of past and present life upon the globe, what an
infinite amount of pure enjoyment has been derived from every
one of these faculties and powers, so that the existence of pain,
which is the necessary correlative of many of them, counts for
nothing in the balance. Eventhat endless variety, which seems
a first principle of the material universe, so absolutely universal
is it, adds in an incalcuiable degree to our enjoyment. It alone
enables us to appreciate beauty, and it is almost certain that we
should receive no pleasure from any of our senses if there were
not an ever-varying series of objects and properties to excite
them to various degrees and kinds of action. The conception
that these almost infinite possibilities of enjoyment have come
into existence as a necessary result of certain self-existent laws
of self-existent matter, and have therefore not been in any way
foreseen or designed by any intelligence, is one which seems too
improbable to be permanently held by any thinker who will care-
fully examine the evidence from this point of view.

The last chapter—on the Moral Aspects of Evolution—is very
well written, and deserves careful consideration. We have only
space to notice what is termed the origin of moral species. The
world has ever persecuted its reformers and put its prophets to
death. The best, the wisest, and the most unselfish men have
often left no posterity to inherit their good qualities. How, then,
has the world advanced morally and intellectually? Mr. St. Clair
imputes it to the generative action of mind upon mind, a more
powerful agent in spreading truth and goodness than hereditary
transmission. Each great mind acts upon all those which are
somewhat lower than itself, and tends to raise them to its own
level. ‘‘The man in whom the higher truth or higher virtue is
first found may be said to constitute a new moral ‘ species’ or
‘variety.. The men who are nearest to him in the points
in which he is distinguished are the species from which he
probably has sprung, and being nearest to kim would require

232 Notices of Books. (April,

least alteration in themselves to make them quite like him. The
influence fitted to produce this alteration is the presentation of
his peculiarities before them in the example of his life or
sufferings, in his verbal teaching or his written works. These,
therefore, are the ‘ conditions of the environment’ which induce
‘variation’ in a number of individuals, and convert them into
the new species; it is not that offspring are generated in the
parental likeness, but one species is evolved from another.
Thus we have the wonderful fact that a new moral species can
create the conditions which will cause others to vary into its
likeness—the highest moral life agrees with the lowest physical
life in possessing a protoplasmic power of multiplying itself
indefinitely by contact. Not only has Natural Selection trans-
ferred its action to the mind, but the environing conditions which
occasion the mental variations before they are selected have also
to a large extent become mental.” But this does not, as Mr. St.
Clair remarks, explain how the variations arise which give purer
conceptions and higher impulses to some men than to all
the rest of mankind; neither does it explain why these danger-
ous gifts, often bringing persecution and death to their pos-
sessors, should have such a marvellous power of spreading, and
prove so fascinating to many, to whom they will in all probability
bring no better fate. He concludes that there is no other expla-
nation but that truth and goodness have an immutable beauty
proper to themselves, attractive to minds and consciences capable
of perceiving the true relations of things; and that this can only
be looked upon as due to the great Fount of all things.

We can cordially recommend this book to all who take an
interest in the wider bearings of the doctrine of evolution. The
writer is thoroughly imbued with the spirit of his subject, and
even the experienced student will find much that is suggestive in
the way in which the facts of well-known writers are presented
and discussed. Some of the greater philosophical difficulties
are, it is true, avoided rather than overcome ; but we nevertheless
feel that the book is well calculated to diminish anti-Darwinian

prejudice, and to help forward the reconciliation of science with
religion.

The Conservation of Energy. Being an Elementary Treatise on
Energy and its Laws. By Batrour Stewart, M.A., F.R.S.,
Professor of Natural Philosophy at the Owen’s College,
Manchester. London: Henry S. King and Co. 1874.
Crown, 8vo. 180 pp.

Tue Doctrine of the Conservation of Energy, which was

indicated in Mr. Justice Grove’s work on the “ Correlation of the

Physical Forces’ some thirty years ago, has been considerably

developed since the exact determination of the relationship which

1874.] Notices of Books. 253

exists between heat and mechanical work. Professor Stewart
has written an admirable treatise on Heat, and has elsewhere
discussed the Conservation of Energy with consummate ability.
We are not disappointed by this more comprehensive treatment
of the subject. He tells us succinctly in the preface his mode
of discussing the subject. He divides our knowledge of the
universe into two branches: the one knowledge of it as a vast
physical machine composed of atoms swimming intheluminiferous
ether; the other, the laws which regulate the working of this
machine; in other words, the laws of energy.

In the first chapter, energy is defined as ‘‘the power of
overcoming obstacles, or of doing work,” as instanced by a rifle
bullet in motion. The work is to be measured by some unit,
preférably the kilogramme for weight, and the metre for height ;
and by multiplying a weight raised by the vertical height through
which it is raised, we get the work done in kilogrammetres.
Next we have various examples of the change of energy of
position into energy of motion, and finally into heat. The usual
and satisfactory examples of the head of water, the bent cross-
bow, and the wound up watch are adduced, and the advantages
of energy of position are exemplified by happily comparing a
water-mill and a windmill with a rich and poorman. In the one
case we may turn on the water whenever it is most convenient
for us, but in the other we must wait until the wind happens to
blow. The former has all the independence of a rich man; the
latter all the obsequiousness of a poorone. If we pursue the
analogy a step further, we shall see that the great capitalist, or
the man who has acquired a lofty position, is respected because
he has the disposal of a great quantity of energy; and whether
he be a nobleman or a sovereign, or a general in command, he is
powerful only from having something which enables him to make
use of the services of others. When the man of wealth pays a
labouring man to work for him, he is in truth converting somuch
of his energy of position into actual energy, just as a miller lets
out a portion of his head of water in order to do some work by
“its means.” This (second) chapter continues with an account of
the functions of machines, the conversion of motion of a mass
into heat, and the nature of the motion called heat. The next
chapter discusses the various kinds of energy; gravity, elastic
forces, cohesion, chemical affinity, electricity, magnetism. The
classification of elastic forces among the energies is unusual, and
we have always regarded elasticity as a function of cohesion, not
as due to any separate and distinctive force. Prof. Stewart
speaks of the ‘‘ force of elasticity,” but is it not rather a property
belonging to certain bodies under certain conditions than a force?
It does indeed require energy to bend a bow, but is not that energy
expended in partially overcoming the cohesion of the molecules
in one direction, and in approximating the molecules against
their molecular motion in another? A useful condensed list of

234 Notices of Books. (April,

energies is given (pp. 78-82), and this is immediately followed
by the ‘‘ Law of Conservation.”. This law asserts that the sum
of all the various energies of the universe is aconstant quantity,
or as Prof. Stewart puts it—

(A) + (B) + (C) + (D) + (E) +(F) + (G) +(H) =a constant quantity.
Not that any single one energy is constant in itself, for they are
perpetually changing into each other, but that the sum of these
variable quantities is a constant quantity. The fourth chapter is
entirely devoted to an account of the transmutations of energy,
and the fifth gives the history of the idea from the earliest times,
and then discusses at some length the dissipation of energy.

In discussing the early atomic theories, Professor Stewart has
omitted the claims of Kanada, a Hindu philosopher, whose
atomic theory was not only more complete and philosophical than
that of Leukippos and Demokritos, but was also much earlier.
A very interesting account of this theory (too little known in
this country) is given by Sir John Colebrooke in his admirable
articles on the Philosophy of the Hindus (in the ‘‘ Proceedings of
the Asiatic Society”). The statement that Demokritos ‘‘ was the
originator of the doctrine of atoms”’ is also incorrect, even as

regards Greek philosophy, because Demokritos took the idea,

which he indeed extended, from Leukippos. Again, the idea of
the ethereal medium pervading all space was originated by the
Hindus long before the time of Aristotle, and we protest against
the assertion that Aristotle “caught a glimpse of the idea of a
medium,” when we find his constant mention of the AiOjp
and remember that he introduced the very name for it which we
now adopt. We claim for the ancients much more than our
author is disposed to grant them: surely they possessed a very
definite atomic theory, a fairly definite idea of an ethereal
medium pervading space, an exact idea of the transformation of
one kind of matter into another, through the intervention of some
external principle of motion; and at an earlier date than all, a
four-element theory, which we accept in a too literal sense, but
which was philosophical and profound for those unexperimental
ages. Professor Stewart next passes on to ‘“ Descartes, Newton,
and Huyghens on a Medium.” ‘In modern times, he writes
Descartes, author of the vertical hypothesis . . . ” (vertical
should surely read vortical), but Anaxagoras of Klazomene
conferred upon his v,ovs, which is essentially a mover of
matter, the property of inducing the vortical motion of atoms;
and of all modern philosophers, to our mind, Descartes has most
drawn upon the ideas of the ancients in his Cosmogony. ‘The
historical portion of this chapter is very slight and insufficient in
our opinion, but no doubt a longer historical survey would have
occupied space required for other matters.

The theory of the dissipation of energy is indeed a startling
one; we are perpetually converting work into heat, but it is
impossible to reconvert all the heat produced into work again.

o-

1874.] Notices of Books. 235

What must result? ‘The mechanical energy of the universe
will be more and more transformed into universally diffused heat,
until the universe will no longer be a fit abode for living beings.”’

ah “If we could view the universe as a candle not lit,
then it is perhaps conceivable to regard it as having been always
in existence; but if weregard it rather as a candle that has been
lit, we become absolutely certain that it cannot have been burning
from eternity; and that a time will come when it will cease to
burn. We are led to look to a beginning, in which the particles
of matter were in a diffuse chaotic state, but endowed with the
power of gravitation, and we are led to look to an end in which
the whole universe will be one equally heated inert mass, and
from which everything like life, or motion, or beauty, will have
utterly gone away.”

The final chapter discusses the position of life:—An animal is
defined asa machine of a delicacy which is practically infinite, the
condition or motions of whichwe are utterly unable to predict. And
what is life? ‘* Life is not a bully who swaggers out into the open
universe, upsetting the laws of energy in all directions, but rather
a consummate strategist, who, sitting in his secret chamber,
before his wires, directs the movements of a great army.”
Prof. Stewart has surely misread a statement made by Rumford :—
“‘Tt was seen that in order to do work,” says our author, p. 163,
‘(an animal must be fed; and, even at a still earlier period
Count Rumford remarked that a ton of hay will be administered
more economically by feeding a horse with it, and then getting
work out of the horse, than by burning it as fuel in an engine.’
Mmgeord words are these:* . .-. ‘* Heat may thus: Be

produced merely by the strength of a horse, and, in case
of necessity, this heat might be used in cooking victuals. But
no circumstances could be imagined in which this method of
procuring heat would be advantageous ; for more heat might be
obtained by using the fodder necessary for the support of the horse
as fuel.” ‘This latter must be the right view of the case, for part
of the energy derived from the consumed hay is dissipated in the
very working of the horse’s great muscular mechanism, and a
part of the work done by the horse is dissipated as heat by the
friction of the working parts of the machine which it moves,
whether that machine be one for producing heat by friction, as
in Rumford’s experiment, or for any other purpose.

Prof. Stewart’s work is interesting and very readable. We
commend it to all readers, whether scientific or otherwise, who
are desirous of learning the most recent ideas connected with
the various transmutations of the different physical forces.

* “An Enquiry Concerning the Source of the Heat which is Excited by

Friction.” Read before the Royal Society, Jan. 25th, 1798. The italics are
our own.

236 Notices of Books. (April,

Contemporary English Psychology. Translated from the French
of Tu. Risor. London: Henry S. King and Co. 1873.
8vo. 328 pp.

Ir is always a matter of considerable interest to know the light

in which our intellectual work is regarded by those who are not

our own countrymen. The natural bias which causes a man or

a people to view the literary or philosophical production of a

fellow-countryman as unsurpassed works is not present in foreign

criticism. We know how eargely M. Taine’s ‘‘ Notes on

England,” and on English Literature, were received; and

although without doubt this was partly due to the eminence of

the man, the cause mentioned above had also much to do with it.

We have a powerful school of Psychology in this country at the

present time, and a comparison and differentiation of the views

of the more prominent members of it is desirable and important.
Philosophy was, in the beginning, universal science; it
treated of ‘“‘the universality of things, the all.” Then came a
separation of one of its parts, mathematics, some two centuries
after the time of Pythagoras. But, according to M. Ribot, the
old philosophy of Plato and Aristotle is still the universal
science :—Metaphysics follow physics, politics follow morals,
physiology follows psychology. In the middle ages, medicine
and alchemy separated from it, and in the eighteenth century
physics. Then philosophy in its broadest sense began to lose its
comprehensiveness: nature was wrested from it; God and man
remained to it. Philosophy once included all things, ‘ principles
and consequences, causes and facts, general truths and results; ”
ultimately ‘it will be metaphysics and nothing more.” It has
been said that ‘‘ metaphysicians are poets who have missed their
vocation,” and M. Ribot considers the assertion just, but we
must venture to differ from him. For surely the precise, hard,
logical mode of thought which the metaphysician must adopt ;
his cold, lifeless theories and harsh unyielding laws ill consort
with that warm flow of imagination which spontaneously should
burst from the poet. Hegel’s logic may indeed ‘border on

Faust;” but what a thoroughly metaphysical poem Faust is!

If all poems were like Faust, then indeed the poet and the

metaphysician would have much incommon. And what of the

end of all philosophy? Let us suppose all our questions
concerning God, nature, and ourselves, finally answered. What
would remain for human intelligence todo? This solution would
be its death. All enquiring and active minds will be of Lessing’s
opinion on this point: ‘‘ There is more pleasure in coursing the
hare than in catching it.” Philosophy will keep up its activity
by its magical and deceiving mirage. Were it never to render
any other service to human intelligence than that of keeping it
always on the alert, of elevating it above a narrow dogmatism, by
showing it that mysterious beyond which surrounds and presses
upon it in every science, philosophy would do enough for it.”

1874. ] Notzces of Books. 237

M. Ribot considers at considerable length the proper definition
of the Science of Psychology (a word first introduced by
Goclenius). He shows that, during the seventeenth century, the
science of the soul was called metaphysics; and that, hence,
metaphysics and psychology have many points of connection. In
its widest sense, he considers that psychology embraces ‘‘all the
phenomena of mind in all animals,” or if we follow Mr. Stuart
Mill, and make more exact divisions, we have General Psycho-
logy: the study of the phenomena of consciousness, sensation,
thought, emotions, relations, &c., considered under their most
general aspects. This embraces Comparative Psychology, and
Psychological Teratology, or a study of anomalies and monstro-
sities. At the conclusion of his most interesting introduction,
our author tells us that since the time of Hobbes and Locke,
England has done most to forward Psychology.

Then follows the main part of the book: a condensation of the
psychological systems of Hartley, James Mill, Herbert Spencer,
Alexander Bain, G. H. Lewes, Samuel Bailey, and John Stuart
Mill. Thus the survey extends over about a century, but is
mainly confined to the last thirty years.

The agreement of these philosophers in regard to all main
points in each other’s systems is clearly shown. These main
points may be briefly stated as follows:—(a). Psychology
examines the facts of consciousness, and connects those facts
by definite laws. (b). It deals with phenomena, not knowing the
nature of the soul or mind. (c). It studies these phenomena
(1) objectively by signs and actions which interpret them, and
(2) subjectively by memory and reason. Consciousness consists —
of ‘“‘acontinuous current of sensations, ideas, volitions, feelings,”
&c.; it is made up of the perception of a difference, and the
perception of aresemblance. Perceptions are internal conditions
corresponding to external conditions. These and many other
definitions are given in the concluding remarks, in a clear, crisp
form, very readable and understandable, and quite divested of
unnecessary technicalities. We feel assured that the work will
be received with open arms by the largely increasing school of
English psychologists.

Animal Locomotion; or Walking, Swimming, and Flying.
With a Dissertation on Aéronautics. ByJ. BELL PETTIGREW,
M.D., F.R.S., F.R.S.E., Pathologist to the Royal Infirmary
of Edinburgh. London: Henry S. King and Co. 1873.
Crown 8vo. Illustrated. 264 pp.

Tuts work belongs to the ‘International Scientific Series,” five

or six volumes of which, including Professor Stewart’s ‘‘ Con-

servation of Energy,” have already appeared, and many more
are announced. The object of the author is to explain various

VOL. IV. (N.S.) 2H

238 Notices of Books. (April, —

difficult problems in animal mechanics, and to discuss some of
his views concerning the possibility of flying. A somewhat
long introduction treats of the various motions possible to dif-
ferent creatures. It is herein shown that walking, swimming,
and flying are only modifications of each other. ‘Walking ~
merges into swimming, and swimming into flying, by insensible —
gradations,” and the various differences in the actions are due to
the fact that the media of support differ in density, earth for
walking, water for swimming, air for flying. The relation of
these actions is well shown by the fact that birds and inse¢ts can
perform them all, while a large number of creatures can both
walk and swim. ‘‘The subject of flight has never until quite
recently been investigated systematically or rationally, and as a
result, very little is known of the laws which regulate it. If
these laws were understood, and we were in possession of trust-
worthy data for our guidance in devising artificial pinions, the
formidable Gordian knot of flight there is reason to believe
could be readily untied.” Thus early in the book (page 4) does
our author introduce an evidently pet idea that artificial flight is

a possibility. The introduction is continued with various dis-
cussions of the operations performed during walking, swimming,
and flying; thus we are told that the extremities of animals act
as pendulums during walking, and describe curves like a figure
of 8, as also do the bodies of fish in swimming, and the wings
of birds in flying. Dr. Pettigrew, indeed, claims the discovery
of the figure-of-8 theory. In the succeeding part of the work
this theory is applied to, and illustrated by, the progression of *
various birds, beasts, and fishes. Some beautiful original
drawings are given to illustrate these motions; we may notice
particularly those which illustrate the movements ofthe wings
of the wasp and fly (pp. 139—141).

Passing on to the subject of aéronautics, our author shows the
extreme difficulty of the problem of artificial flight to consist,
among other things, in ‘‘(3rd) the great rapidity with which
wings, especially insect wings, are made to vibrate, and the
difficulty experienced in analysing their movements; (4th) the
great weight of all flying things when compared with a corre-
sponding volume of air; and (5th) the discovery of the balloon,
which has retarded the science of aérostation, by misleading
men’s minds, and causing them to look for a solution of the
problem by the aid of a machine lighter than the air and which
has no analogue in nature.” The flightists may now be divided
into two classes :—1st, those who advocate the use of balloons;
andly, those who consider that weight greater than the air is
essential. This second class has two divisions :—‘‘ (a) those
who advocate the employment of rigid inclined planes driven
forward in a straight line, or revolving planes (aérial screws) ;
and (b) such as trust for elevation and propulsion to the vertical
flapping of wings.” Dr. Pettigrew’s work, although it may not

=

1874.] Notices of Books. 239

appeal to a large number of readers, is very readable, and will
certainly be a great boon to the members of the Aéronautical
Society.

Fruits and Farinacea ; the Proper Food of Man. By the late
Joun Smiru, of Malton. Manchester: John Heywood ;
London: F. Pitman. 1873. 112 pp. Crown 8vo.

Tus small work, which has been edited by Professor William
Newman for the Vegetarian Society, contains the substance of a
work bearing the same title first published in 1845. It is an
essay on vegetarianism, and endeavours to prove that vegetables
were the original, and are the natural and best food of man.
That such diet was originally adopted by mankind the author
tries to show by various quotations from Genesis and other early
writings. In the second chapter proofs are derived from our
organs; the teeth are said to be unsuited to the mastication of
animal food; and the argument is forwarded by the alleged in-
appropriateness of our salivary g glands, alimentary canal, stomach,
colon, czecum, and liver. We “really begin to wonder how man
can have lived for centuries on an omnivorous diet if all his
organs are unsuitable for anything but a vegetable diet. A curious
table is given in the third chapter, showing the various times
which different substances take to digest, after Dr. Beaumont.
The amount in each case is not mentioned,—presumably equal
weights; if so, it is not to be wondered at that soft boiled rice
should digest in one-third the time of beef or mutton. Surely
the composition of the various kinds of food should be given, in
order to enable one to form ajust estimate. We select a few
substances :—

Hours. Mins.
Rice, boiled soft : I O
Tapioca, stale bread, milk . 2 oO
Apple dumpling . . see fo)
Potatoes and turnips boiled, butter . 3 30
Venison . t Vous I 35
murkey . 2 30
Boiled pork, “hard- boiled eg Bes. B) 30
Salt pork, boiled : 4 30
_ Veal, roasted 5 30

This table is surely no great support to our author’s argument,
when we find that venison takes a shorter time to digest than
tapioca, bread, cabbage, and milk, while boiled potatoes and
turnips take longer than beef and mutton, and actually as long
as that notoriously indigestible substance, boiled pork. Among
other things, an attempt is made to prove that vegetable diet is
es favourable to the moral state ;”’ the use of wine is said to follow
the stimulus of animal food. Noah drank wine and became

240 Notices of Books. (April, —

drunken soon after receiving permission to eat animal food;
Jacob, when he brought his father the savoury mess of pottage,
likewise brought wine. ‘* Again,” says Mr. Smith, “ carnivorous
animals are ferocious; the herbivorous are gentle, sociable, and
playful.” But, we would ask, can anything be more “sociable
and playful” than a dog or a cat, anything more ferocious than
a wild bull? Those who have seen wild horses fight in the
prairies will class the horse with the bull. We cannot discuss
such arguments as these; a similar mode of reasoning to that
employed by Mr. Smith could be made to prove that black is
white. This book appeals to a small class of persons; that it
will convince anyone that vegetarianism is better than our present
system we confidently doubt. We have been unable to find a
trace of sound logic or convincing argument in the whole book,
and are more than ever assured that our omnivorous diet is the
right one.

Geology. By ArcuripaLp Geixiz, LL.D., F.R.S., Director of
the Geological Survey of Scotland. Illustrated. London:
Macmillan and Co. 1874. 18mo. 130 pp.

Tus small volume forms the fifth of Messrs. Macmillan’s Science
Primers, and immediately follows the Physical Geography Primer,
by the same author. The first of the series, by Professor Huxley,
has not yet appeared, and is somewhat eagerly expected, as it
forms an introduction to the whole series, and will without doubt
discuss the modes and advantages of elementary science teaching.
The author of the book before us is well known as an eminent
geologist, and there is nothing to be said about his book in the
way of criticism. The arrangement is clear and good; the
subject-matter treats of sedimentary rocks, igneous rocks, and
‘‘organic rocks,” that is, rocks consisting of the remains of
plants and animals,—such as coal, chalk, and encrinitic limestone.
At the conclusion we have various paragraphs relating to the
crust of the earth considered as a whole, to prove that it has
been upheaved and depressed at different epochs, which actions
have produced tilting, crumpling, and breaking of the crust. We
find here, too, a section on the origin of mountains. A few good
illustrations help the beginner to realise the various descriptions.

A Phrenologist Amongst the Todas, or the Study of a Primitive
Tribe in South India; History, Character, Customs, Religion,
Infanticide, Polyandry, Language. By WiLLt1AM MARSHALL,
Lieutenant-Colonel of Her Majesty’s Bengal Staff Corps.
London: Longmans, Green, and Co. 1873.

THE native inhabitants of the Indian peninsula may be broadly
divided into two great races,—the Aryans, inhabiting the whole

1874.] Notices of Books. 241

of the northern and western plains,—the Dravidians, occupying
the central and southern districts. ‘The first comprehend all the
more civilised peoples—the Mahomedans and Hindoos; the
second are in various lower stages of civilisation, and are mostly
pagans. Besides these there are a number of obscure tribes,
such as the Kols, whose language is allied to some dialects of
Pegu, and the Pariahs and other servile castes, who may pro-
bably represent a remnant of some of the earliest savage inha-
bitants of the country. The Aryans belong to the great Aryan
or Indo-Germanic race, and their language no less than their
physical features allies them to the highest European peoples.
The Dravidians, on the other hand, are more related to the
Mongolian races; and their nearest affinity has been traced by
language to the Finns and Lapps far in the north-western corner of
Europe. Philologists look upon these Dravidians as a much
older people than the Aryans. They probably once spread over
a large portion of Europe and Asia, and entered India from the
north and north-west, occupying the country, and exterminating,
or making slaves of, the rude aborigines. At a later epoch the
higher Aryan type was developed, and drove out the Dravidians
from all the more fertile parts of Europe. This energetic people
were the parents of the Celts in the west, of the Germans and
‘Slavonians in mid-Europe, and of the Sanscrit-speaking Aryans
in the east; and these latter entered India from the north-west,
and took the place of the Dravidians in all the more fertile and
accessible districts as these latter had taken the place of the
older aborigines.

The Dravidians of India now form eight tribes or nations,
speaking distinct though allied languages. These are the Tamil,
Telugu, Kanarese, Malayalam, Tuluva, Toda, Génd, and Khond,
the first five belonging to more civilised peoples possessing
a written character, while the three last are spoken by compara-
tively savage tribes. The smallest of these tribes, the Todas,
is confined to the plateau of the Nilagiri Mountains, and consists
of about 700 individuals. They formerly practised infanticide
as an institution, and the result was that they were rapidly
becoming extinct; but, owing to the influence of the Indian
Government, this has been discontinued for many years, and
they now increase in population with tolerable rapidity. These
Todas are, in many respects, one of the most interesting and
peculiar tribes in the world; and every student of man is in-
debted to Colonel Marshall for the careful study he has made of
their whole physical, mental, and moral nature, and for the well-
illustrated and instructive volume in which he gives both his
detailed observations and the conclusions which he draws from
them.

We will endeavour to sketch in outline the most curious features
of Toda life, in the hope that we may induce many of our readers
to go for fuller information to the book itself.

~

242 Notices of Books. (April,

The Todas live in very small village communities of from
20 to 30 persons. Their houses, or huts, two or three together,
and sometimes all under one roof, are low and somewhat of an
inverted boat-shape, with very low doors (only about three feet
high), and no windows. Attached to every village is a cattle-
pen, and a separate building, which comprises the dairy and the
dairyman’s abode. They live a purely pastoral life, and, perhaps
more than any other people in the world, are absolutely dependent
for their existence on one animal,—the buffalo. Though they
live in a fertile land and a delightful climate, they grow no crops,
and have no kind of cultivation whatever. Though their woods
and hills abound in game, they neither hunt nor trap any living
thing. They keep no domestic animals but the buffalo and the
cat, although the populations around them possess .goats, pigs,
and poultry. They eat no flesh, not even that of the buffalo, of
which they often have a superabundance, but live wholly on milk
and butter, with rice and such other vegetable food as they
obtain in exchange for their surplus dairy produce and for the
young male buffalos for which they have no use. Although
surrounded by strong and often quarrelsome tribes, they possess
no single weapon of offence or defence,—no bow, or spear, or
sword, or club. They never fight among themselves or with
their neighbours. They have no sports of activity or skill.
They have no manufactures, even of the simplest kind. Two
men in every village are set apart for the dairy-work, leaving all
the rest to lead an almost absolutely idle life! Yet they are by
no means savages of a very low type. They are quiet and
dignified in their manners, amiable in disposition, and very good-
looking, the excellent photographs with which the book is
copiously illustrated showing us intelligent and often handsome
faces, in no way distinguishable from those of many of our own
country people. They are courteous to strangers and to each
other, and have an elaborate system of salutations and cere-
monies. Their absolute dependence on the buffalo has led them
to a form of religion in which this animal is the central figure.
They have a sacred breed of cattle, which are distinguished by
carrying bells; and hence ancient bells are sacred. The dairy is
sacred. No one except the dairyman and his assistant may
enter it. During the term of their office, these two men have to
pass absolutely solitary and celibate lives, they and their imple-
ments being touched by no human being. ‘The dairymen who
have charge of the sacred herds are for the time being looked
upon as gods. They keep in the dairy certain relics,—old cow-
bells, knives, and axes,—which are in the highest degree holy,
and which the dairyman, also priest, salutes with certain ceremonies
every morning. The people in general also salute the rising and
setting sun, and have certain vague notions of a future state.

Our author has minutely studied this curious people, and gives
us interesting details of their every custom and ceremony, habit

a
4a

1874.] Notices of Books. 243

and superstition ; so that we obtain a complete picture of the
entire course of their simple lives, and a considerable insight
into their mental and moral nature. Perhaps with somewhat of
a student’s partiality for his favourite subject, he arrives at the
conclusion that they are a very ancient people, and that their
existing customs and mode of life have come down, almost un-
changed, from a period more remote than those of any other race
known to us. He has also gone with extreme minuteness into
their social statistics, taking an accurate census of a number of
villages, and obtaining the ages, sex, and relationships of every
individual. The results are exhibited in a series of tables, from
which some very curious conclusions are drawn. The primitive
custom of the Todas was to kill all female children except one
ortwo. ‘This, of course, resulted in a superabundance of males,
and hence arose the practice of polyandry, or of some women
having two or more husbands, which practice continues to this
day. Although infanticide of females has long entirely ceased,
yet the number of males is still largely in excess. The census
tables seem to show that considerably more male than female
children are born; and it is very ingeniously argued that this is
the necessary consequence of long-continued female infanticide.
It is proved thus. The average Toda family is six children born
to each woman. Now, if wetake three women, the first of whom
has six daughters, the second six sons, and the third three sons
and three daughters, we shall be able to trace the effects of
infanticide on the proportionate numbers of the two sexes. The
first mother has to destroy four daughters, keeping only two.
The second keeps her six sons. ‘The third destroys two
daughters, keeping three sons and one daughter. There will
remain nine sons and three daughters, and these will be the
parents of the next generation. But the majority of these will
be derived from families which produced more males than
females, and as such tendencies are hereditary, the constant
preservation of a similar majority generation after generation
will inevitably result in a male-producing race; and this pecu-
liarity having been established by a long course of artificial
selection, will continue to manifest itself for an unknown period
after the depraved practice which gave rise to it has been
abolished.

The view that close interbreeding is not per se injurious is
strongly supported by the case of the Todas. From time
immemorial they have married together in the same or adjoining
villages, till they are all closely related in various degrees of
cousinship; yet the people seem to be as a whole healthy and
vigorous, and remarkably free from all those diseases supposed
to be produced by close interbreeding. Out of a population of
196, only 2 were malformed.

Colonel Marshall is an ardent phrenologist, yet that despised
science nowhere appears prominently in his book beyond the two

244 Notices of Books. (April,

chapters which he devotes to it. He insists on the remarkable
simplicity and uniformity in the form of the crania of savage
races compared with those of civilised and highly complex
nations like our own; and this agrees with the much greater
uniformity in savage character, and the less frequent occurrence
of men of exceptional mental peculiarities. The extreme care
and minute accuracy with which all the facts relating to this in-
teresting people have been investigated, should secure for the
author the credit of impartiality in the table of the comparative
development of the various phrenological organs in eighteen in-
dividuals (males and females), taken, he assures us, without bias
of any kind. The comparison of the average character denoted
by the table and the observed peculiarities of the race are very
interesting; and we can hardly believe that so intelligent
an observer and reasoner could have failed to discover the
unreality of phrenology if it were so entirely destitute of truth
as it is the fashion with scientific men to assume.

The skull of the Todas is extremely and universally dolicho-
cephalic,—that is long in proportion to its width. This form is
very characteristic of low types of man, unprogressive and
unenergetic. The Ancient Britons, the Lapps, Fins, Siamese,
and some others, are, on the other hand, highly brachycephalic,
that is, the skull is short, and approaches the globular form.
Now Colonel Marshall gives us a suggestive theory of the
meaning of these marked differences of form, and we believe
it is the first theory of the kind that has been advanced; for,
while strenuously opposing phrenology, the craniologists of the
present day have not made the slightest approach to a correlation
of cranial form with national or individual character. Enormous
collections of skulls have been made; they have been figured
and measured with the most scrupulous accuracy; the various
proportions of the different dimensions have been compared; the
averages of different races have been taken,—and all with no
result whatever! It is, indeed, pretty generally agreed that the
higher and more civilised races have the larger brains, and
therefore the larger crania; but as to why these crania should
differ in form and proportion so widely as they do, we obtain no
light whatever. Nor has the study of the anatomy of the brain
led to any more definite results; and even the recent experiments
of Professor Ferrier are capable of various interpretations, since,
while the phrenologists see in them a confirmation of their own
doctrines, Dr. Carpenter maintains that they support his view,
which is that the higher intellectual faculties are situated in the
back of the head, while the development of the forehead only in-
dicates the predominance of faculties common to man and the
lower animals!

According to modern phrenology, the group of organs situated
at the sides of the head, and which thus give it breadth and
fulness, are termed invigorating, being those which give the

1874.} Notices of Books. 245

desire for conflict ; for overcoming obstacles ; for the acquisition
of property; for animal food, and for elaborate dwellings, tools,
and weapons, and which also incite to cunning and treachery.
Tribes which have these faculties in excess will, as a rule, be
warlike, cruel, treacherous, thievish, ingenious in constructing
their weapons, huts, and canoes; fond of animal food, and good
hunters, and sometimes cannibals. Tribes in which they are
markedly deficient, will generally be the reverse of all this,
peaceful, mild, open, honest, idle, careless in their food, huts, and
clothing, and with few tools and weapons. Of course the
proportions of the various organs may vary indefinitely in either
form of cranium, and thus some one or other of these charac-
teristics may be wanting; but, making allowance for this, we
see a marked difference between such narrow-headed races as the
low Australians, and the much higher broad-headed Sandwich
Islanders, or the mild, narrow-headed Esquimaux, and the very
broad-headed, warlike Araucanians. Colonel Marshall believes
that the broad-headed type has been developed in the struggle
for existence, and has in most cases driven out the narrow-
headed where the two have come into contact. It must be
remembered, however, that either extreme is an inferior type, and
that it is the well-balanced organisation, with a brain inter-
mediate in form, if sufficiently large, that will progress most in
civilisation, and will be able to rule and conquer, or exterminate
either extreme type. The objection, therefore, brought by
mee. B&B. Lylor (‘‘* Nature,” Dec. 11, 1873) against our
author’s view, that the comparatively narrow-headed Russians
have subjugated many broader-headed Asiatic tribes, is not to
the point. The Russians are more civilised, in a higher state of
organisation and discipline; and it is this, not their individual
energies, that has now rendered them superior to those Eastern
hordes which, at an earlier period, when their state of civilisation
was more equal, would probably have. overcome them. The
warlike and ingenious Arabs, Afghans, and Malays, are all
markedly brachycephalic. Dr. J. B. Davis states that his
extensive collection of crania shows that, in most cases, the
female skull is more dolichocephalic than the male, but that
among many of the African races the reverse is the case. This
has an interesting bearing on the fact, so strongly insisted on by
our reporters of the Ashantee war, that the African women are
much more industrious and energetic than the men; while we
know that in Africa alone there exists an effective female army.
These are suggestive facts; and it is to be hoped that they will
induce phrenologists to utilise our large collections of the crania
of various races, for the purpose of working out in detail the
peculiarities of national character as indicated by them. This
should be done by actual calliper measurements of every organ
where practicable, so as to introduce precision into the results.
The author of the present volume could do no better service to

VOL. IV. (N.S.) Pay

246 Notices of Books. (April,

his favourite study than by applying himself to this work when
he returns to Europe; and we hope he may be induced thus to bring
prominently before the scientific world a study which the present
writer believes to be founded inductively ona wide basis of observed
facts, and calculated to be of immense importance in elucidating
the mental nature of man, both individually and nationally.

In this short notice we have not been able even to allude
to many of the interesting topics discussed by our author. His
beautifully illustrated volume should be read by every one who
desires to see how much valuable matter a man of genius may
obtain during a few months’ sick leave; and how much light may
be thrown on curious social problems, and on the early history of
mankind, by the careful study of a few scattered families of an
almost extinct tribe of savages.

The Ocean: Its Tides and Currents, and their Causes. By
WILLIAM LEIGHTON JORDAN. Longmans, Green, and Co.,
1873.

THIS is a most vexatious book. We cannot help admiring the

industry with which the author has studied his special subject of

ocean currents, and to a certain degree the originality of his
method of treating it, but in the midst of this we are thrown back |
by the extravagance of originality and error, in the author’s
conceptions of the fundamental properties of matter, and the
laws of motion. His great stumbling block isthe pre-Newtonian
idea that the vis imertie of matter is a continual striving for
rest, or an internal resistance to the continuance of motion. He
endows inertia with positive activity, and makes that activity all

Se ee ees

one sided, by representing it as an inherent property or force of ©
matter which opposes all external force sproducing motion, but —

offers no opposition to the external forces which resist or destroy
motion, or, to use his own words, ‘‘ I have shown that vis inertié

opposes motion in everything, and that its own inherent property —
of vis inertia must tend to bring a body to rest under any —

circumstances whatever, just as much, and in the same manner,

as the action of any force from without; and, secondly, I have |

shown that, as regards the motions of the planets in their orbits,
the centrifugal force which opposes the centripetal force of the
bodies which compose the solar system one towards another, and

all towards their common centre of gravity, is the force of astral —

gravitation opposing that of solar gravitation; so that in their

courses they are borne smoothly along the lines of equlibrium

lying between opposing forces of gravitation.”

we

Mr. Jordan evidently imagines that the quantity of matter —

composing the stars compensates for their distance, and thus —
enables them to control the gravitation of the sun upon the —

planetary members of the solar system. This utter miscon-—

1874.] Notices of Books. 247.

ception of the quantitative force of gravitation due to its
necessary inverse variation with the square of the distance
vitiates completely all the reasoning based upon it.

A further confusion is introduced by another paradox, which
appears to be of Mr. Jordan’s own invention, viz., ‘the motive
force termed evanescence.” We are told that it implies a motion
of the evanescing particles, and gravitation tending to cause
contraction necessitates a motion of the remaining particles;
and since contraction is a necessary consequence of evanescence,
having effect wherever evanescence occurs, it must act towards
every point from which evanescence acts, and thus divide the
universe into separate masses, and also that “‘ certain forces are
in play, causing constant change of form and place; and to the
combined action of these forces (to which no name has hitherto
been given) I have applied the term evanescence.”

In spite of these explanations and a good deal more of similar
disquisition, we confess our inability to understand evanescence.

When, however, Mr. Jordan fairly plunges into his proper
subject, the Ocean, and deals with the phenomena of its currents
apart from his paradoxical notions of “ inertia,” &c., he displays
an amount of careful study and research that render his errors
concerning fundamental physical laws the more vexatious.
Some of his critical discussions of the theories of others are as
remarkable for their clearness as his exposition of his own theories
are for their obscurity. The following passage is an example.”

“It seems to me that the manner in which gravitation
would tend to restore disturbance of the normal level, such as
those indicated by Dr. Carpenter, would naturally be by tidal
movements, or easy, imperceptible movements of the whole
mass of water intervening between the higher and lower levels,
the former sinking and the latter rising simultaneously, just as
when a trough half full of water is tilted on one side, the level
of the water is maintained, not by the surface water streaming
over the lower side, but, excepting the effects of friction against
the sides and bottom of the trough, by an equable motion of the
whole mass of water.”

‘When a narrow channel lies between the higher and lower
level, as in the case of the Mediterranean and Baltic, this
movement would form a rush of water through the Strait, but not
an upper rather than an under current. It so happens that, in
both these cases, so elaborately considered by Dr. Carpenter,
the higher level is also the lighter water; and, therefore, by
Captain Maury’s simple theory, the specific gravity is restored, or
an increase of the difference prevented by the heavier water
running as an under current towards the lighter, and the lighter
as an upper current towards the heavier. Suppose that instead
of the lighter water being at the higher level, as in these two
cases, the heavier were so, will any one contend that the level
would be restored by a surface current from the higher to the

248 Notices of Books. (April,

lower level? Is it not evident that the sweeping assertion that
differences of level will be restored by surface currents is a
mistake? The course of currents, as the level is being restored,
clearly depends upon the relative specific gravity of the water at
the different levels. The heavier water will form the under
current, and the lighter the upper, regardless as to which may be
at the higher or lower level; and, if there be no difference of
specific gravity, the level will be restored by a tidal movement
forming a current through any narrow channel intervening, but
not an upper rather than an under current. The systems of
upper and under currents through the Straits of Gibraltar and
the Sound are clearly the result of differences in specific gravity,
as explained by Captain Maury’s theory, which had better be left
in its origifal simplicity, for this modification with which
Dr. Carpenter has attempted to encumber it is not an im-
provement, but an erroneous complication.”

Here we have the vulnerable point of Dr. Carpenter’s modified
resuscitation of the old theory of oceanic circulation clearly —
indicated, and a home-thrust of clear, sound reasoning fairly
delivered through it. As this point is the very heart of Dr.
Carpenter’s contribution to the subject, the thrust is fatal. It is
followed by further and equally clear and able discussion of the
details of Dr. Carpenter’s arguments, and of the theories off
Maury, Rennell, Herschel, &c. This chapter xx. of Mr. Jordan’s
book is really excellent, and worthy of careful reading, but we
fear that it will not receive the attention it deserves, on account of
the bad impression or prejudice which the author’s fundamental
physical errors must induce.

Cosmical theories are always dangerous, and their proprietors
are always subject to a greater or lesser amount of martyrdom.
Even if the theory is sound, its owner must die in order to obtain
its acceptance; and if it is wrong, as usually happens, it is”
liable to insinuate itself amidst all his sounder thoughts and
positive researches, and poison or intoxicate his common sensé
itself. Even if he has the exceptional strength of mind necessary
for keeping his great theory from this sort of usurpation, he is
a suspected visionary, and his most sober speculations are
unnoticed.” We fear that Mr. Jordan will not escape these perils.

Outlines of Natural History for Beginners. Being Descrip-
tions of a Progressive Series of Zoological Types. By
H. AtiteyNnE Nicnorson, M.D., D.Sc., M.A., PhD
F.R.S.E., &c. London : Blackwood and Sons. ;

Tuis is a clearly-written, unpretending sketch of the subject
which it treats, and well adapted to its object, viz., to assist the
teaching of zoology in schools. The mode of presenting the

1874.] Notices of Books. 249

subject differs somewhat from that which is commonly adopted.
Instead of at first presenting a general view of the animal
kingdom, and its greater divisions into sub-kingdoms, Dr.
Nicholson at once describes the individual types representative
of the smaller sub-divisions or classes, commencing with the
Aniseba as typical of the class Rhizopoda, and so on up to the
dog as the representative of the Mammalia. The sub-kingdoms
are afterwards described in the concluding chapter. The types
are well-selected, and their characteristic features plainly de-
scribed, though, of course, only in outline, the reproductive
organs and the more minute details of internal structure not
being described, the attention of the pupil being directed to the
conspicuous points of structure, more especially to those which
are external.

It is doubtless more in accordance with strict philosophy to
take details first, and then to pass from them to the broader
generalisation ; but, in teaching, this method is attended with
some disadvantages. We think that, on the whole, it would
have been better in a work of this kind to have commenced at
first with an outline of the most general kind, and then to have
filled it up with the matter which forms the bulk of this little
work. The relations of the different classes to each other would
have been better understood after the pupil had been made
acquainted with the general characteristics and the broader dis-
tinctions between the sub-kingdoms. As it stands, the step by
which he is carried from the Cephalopoda to the fishes is made
no broader than that by which he passes from the Crustacea to
the Arachnida. Ina work of this kind, the greatest difficulty is
to determine what should be omitted ; and opinions must neces-
sarily vary rather widely on this point. As an expression of our
own opinion, we think that Dr. Nicholson might advantageously
have told the school-boy and girl just a little about the prede-
cessors of the present generations of animal life; for instance,
when he tells them of the rarity of the Brachiopoda, and his
reasons for selecting an Australian representative of this group,
he might have referred to the comparative abundance of their
fossil remains. Thus some of the ancient links between the
fishes, reptiles, and birds might have been described just suff-
ciently to awaken the curiosity of the pupil and indicate the
bearings of his present study upon that of the ancient history of
our globe.

We are rather inclined to quarrel with the title of the book, as
it sanctions and maintains the very narrow, popular fallacy of
regarding zoology as the whole of natural history. ‘‘ Outlines
ey” would have been a sounder and more expressive
mule, °

250 Notices of Books. (April,

Manual of Lunacy ; a Handbook Relating to the Legal Care and
Treatment of the Insane. By LytrLeton S. WInsLow,
M.B., &c. With a preface by ForBes WINSLow, M.D., &c.
London: Smith, Elder, and Co.

Nort being learned in the law, it is with diffdence that we
express an opinion upon the work before us. Still a careful
perusal leads us to conclude that the author is thoroughly master
of his subject, and that his book will be of great value to all
those members of the medical profession who devote themselves
to the care of the insane, or who are called upon to give evidence
on the mental condition of persons accused of crime. The
section on ‘** Medical Evidence in Court ” contains advice which
may be useful to other scientific men as well as to physicians
when they have the misfortune to appear as witnesses in a court
of justice. The unfair stratagems of counsel in dealing with
technical evidence are alluded to in a manner which some,
doubtless, among our readers will be able to appreciate from
personal experience.

The statistics on the varying amount of insanity and idiocy in
different countries give wide scope for speculative inquiry. Why,
for instance, should an Englishman or an Irishman be nearly
five times more liable to insanity than an Austrian? Why, in
the little German state of Oldenburg, should 1 in every 301 of
the gross population be insane, whilst in Saxony the ratio is only
Iin 1427? Neither race, nor government, nor religion seems to
offer any clue to such a discrepancy as the latter.

Introduction to the Study of Organic Chemistry. By H. E,
ArmstTRONG, Ph.D., &c. London: Longmans and Co.

Tuis volume belongs to the useful series of ‘‘ Text-Books of
Science’ which Messrs. Longmans are at present bringing out.
We cannot say that the work displays any very striking
characteristics either for good or evil. The author, having first
explained organic chemistry as the chemistry of carbon com-
pounds, touches briefly upon formule, empirical and rational,
and upon the action of various reagents upon the carbon
compounds. He then passes on to the family of hydrocarbons,
and considers the remaining groups of carbon compounds in
their relation to the hydrocarbons. Those who take up this
volume as a book of reference, and search in it for information
concerning animal and vegetable substances of importance in
nature or in the arts will find themselves disappointed. But to
furnish such information is certainly no part of the author’s plan.
His object has been to describe only those compounds whose
‘relations to other well-understood bodies have been satis-
factorily established.” The work is in its nature systematic,
and substances whose constitution and relations are unascer-

1874.) Notices of Books. 251

tained must, therefore, be left provisionally unnoticed. The
more chemistry succeeds in developing itself as a primary and
exact science, the more it must, of necessity, abandon the merely
descriptive and concrete features which marked its earlier days.
That by so doing it must lose a certain portion of its attractions,
and appeal to a different class of minds, is undeniable. To the
student prepared to accept these changes we believe that Dr.
Armstrong’s work will be of value.

The Birth of Cheniistry. (Nature Series). By G. F. RopweE tt,
F.R.A.S., &c. London: Macmillan and Co.

Is a knowledge of the history of chemistry necessary ? No, and
yes! It is quite conceivable, for instance, that a man without
any knowledge of the origin and early development of the science
might be the most brilliant and successful experimenter,—the
most accurate analyst the world has produced. Nor can it be
contended that the practical applications of the science are in
the smallest degree promoted by an acquaintance with its rise
and progress. But it is difficult to comprehend the philosophy
of chemistry, or to view it in its relation to other sciences,
without an acquaintance with the rise, the reign, and the decay
of the successive theories which have prevailed in past days.
As a branch of culture and a means of intellectual discipline,
the history of science may justly claim a high rank. It is with
this view, evidently, that the author approaches his subject. “I
have endeavoured,” says he, in his preface, ‘‘to trace the rise
and early development of a very old science, mainly that we may
mark the attitude of thought which actuated the scientific mind
in bygone times, and may thus be led to compare the ancient
with the modern method of evolving ideas and building them up
into a connected whole.”’ The history of science is to be studied
as a basis for the methodology of science. ‘The author likens
the development of chemistry to the erection of a house. ‘ The
time when the foundation-stone was laid is too remote to be even
suggested ; the basis of the edifice is sunk deep in Eastern soil;
the walls were slowly and laboriously raised during the middle
ages, and were completed by Lavoisier, Black, and Priestley.”
The similitude is, in one important sense, misleading. Succes-
Sive generations of experimentalists and inquirers do not merely
add to the works of their predecessors. As Mr. Rodwell has
elsewhere shown, they pull down and rebuild; they modify,
they transform. And ever as they execute such changes, they
dream that their own work is final and unchangeable. The
world has, not for the first time, had its ‘‘modern” chemical
views taught from every professorial chair, and eagerly imbibed
by crowds of students. But before half a century had passed,
the ‘‘modern” had become obsolete, and had been swept into

252 Notices of Books. (April,

the limbo of forgottenness. Mr. Rodwell pursues his subject no
further than to the dawn of modern pneumatic chemistry,—the
epoch of Hales and Boerhaave, Lemery and Mayow. He has
produced a thoughtful, suggestive, and decidedly readable book,
which we hope will be duly appreciated.

Elements of Chemistry, Theoretical and Practical. By W. A.
Mitter, M.D., LL.D. Revised by HrerBert McLeop,
F.C.S. Fifth edition, with additions. London: Longmans,
Green, and Co.

‘Loox for it in Miller” we have repeatedly heard said, when
some rather recondite piece of chemical information had been
vainly sought for in more voluminous works, or in files of
scientific periodicals. And very often in “Miller” the fact
required was found. Hence it is no wonder that the ‘‘ Elements”’
have gradually secured that place in the favour of students which,
consule Planco, was held by Graham and Turner. That a new
edition was required is, therefore, perfectly natural.

The revision which the work has undergone does not consist
merely in the insertion of the most important novelties dis-
covered since the appearance of the fourth edition, but in
a re-arrangement of the non-metallic elements which the editor
conceives will ‘facilitate the progress of the student in the
theoretical part of the science.”

Many of the compounds of carbon have been removed to an
appendix, as also the section on gas-analysis. An account has
also been given of the most recent researches in thermo-
chemistry,—a subject which is attracting the attention of some
of the ablest chemists of the day, and which promises to play an
important part in the progress of the science.

°

The Preparation and Mounting of Microscopic Objects. By
Tuomas Davies. Second Edition. Edited by JoHN
Matruews, M.D., F.R.M.S. London: Robert Hardwicke.
1873.

Tue former edition of this valuable little work has long been

known to microscopists for the eminently practical manner in

which its special subjects are treated, making it one of the most
useful aids to the student commencing microscopical work.

The new edition will by no means disappoint its readers, the
added matter amounting to fifty-eight pages. It is much to be
regretted that the state of the author’s health has prevented his
personal superintendence of the work, but he has an able editor
in Dr. Matthews, in whose hands he placed his copious store of

1874.] Notices of Books. 253

material. The manuscript was also submitted to Mr. T. Charters
White, late secretary of the Quekett Microscopical Club, who .-
made several valuable additions.

The book commences with an introductory chapter by the
editor, containing an account derived from various sources of
reagents used in histological inquiries; this will be of especial
value to those commencing the study of minute anatomy. The
original beginning of the work now forms chapter ii., which,
under the title of ‘“‘ Apparatus,” treats upon the materials used
in mounting objects, such as glass slides, covers, and the other
necessaries of the microscopist’s work-table ; it is here, as else-
where, evident that the writer has seen and done everything that
he describes.

The chapter on ‘‘ Dry Mounting,” in addition to what might
fairly be expected on the subject, gives a somewhat detailed
account of such objects as require special treatment before
mounting in this manner, such as the collection, preparation,
and cleaning of Diatomacee the mode of treating deep-sea
soundings, both of which subjects are very fully treated, and
much other valuable information.

In the portion devoted to ‘‘Balsam Mounting” some useful
hints are given respecting the preparation of crystals.

The much disputed matter of ‘Fluid Mounting” is very fully
dealt with, the author not only giving his own experience but
also that of many other eminent microscopists. The chapter on
dissection will prove useful to those interested in the subject,
and to the same class of students the very full account of the
processes of injecting and staining tissues will be welcome.

”

’

Half-Hours with the Microscope. Being a Popular Guide to the
Use of the Microscope as a means of Amusement: and
Instruction. By Epwrin LanxesTeErR, M.D. Illustrated from
Nature by TuFFEN West. New edition, with a chapter on
the Polariscope, by F. Kirron. London: Robert Hard-
wicke. 1873.

THE principal new feature in this edition is the chapter on the

Polariscope, a subject generally avoided by writers on the micro-

scope; and as a natural consequence this valuable aid to

histological researches is, in too many instances, looked upon
as a mere toy: the few pages by Mr. Kitton will be a great help
to those needing information respecting the use of their
polarising apparatus. The ‘“half-hours” are, ‘‘On the Structure
of the Microscope,” ‘‘ With the Microscope in the Garden,”

“In the Country,” ‘‘At the Pond Side,” ‘At the Sea-Side,”

“Indoors,” and ‘‘On Polarised Light.” The work will be, as

was the former edition, of great service in guiding young

microscopists as to where they are to look for employment for

VOL. IV. (N.S.) 2K

254 Notices of Books. (April,

their instruments; those who are without friends of kindred
pursuits, or have not access to any of the now numerous micro-
scopical clubs, will find Dr. Lankester a useful guide, and it will
be their own fault if they do not learn something.

With regard to the illustrations, the artist is so well known
that comment is needless.

Evenings at the Microscope ; or Researches among the Minuter
Organs and Forms of Animal Life. By PuHit1p HENRY GossE,
F.R.S. New Edition, 1874. Society for Promoting Christian
Knowledge.

Att who know the works of this most agreeable writer will be
pleased to find that a second edition of this well-known work has
been required; Mr. Gosse writes as those only can who have
examined for themselves the objects they are describing. The
greater part of the illustrations are from drawings on wood by
the author, and it is to be regretted that so little pains should
have been taken in printing to do them justice.

The descriptions of the various objects are interspersed with
the needful directions as to magnifying power and apparatus
employed, as well as numerous hints for collecting; this is a
matter too generally neglected in describing the results of
microscopical observations : microscopists who are expert them-

selves are apt to suppose that everyone knows as a matter of ©

course how to follow the author, who has probably in many cases
arrived at his conclusions by some peculiar mode of operation.
All praise is due to Mr. Gosse for his consideration of the wants
of young students.

In describing the structure of wool, the author still adheres to
the old theory that the felting qualities of wool are dependent
upon the serrations, instead of the undulations or waves which
are very evident in the finer kinds of wool, merino for instance.*
If hair was of good felting quality in proportion to its superficial
roughness, surely the bat’s hairs with their whorls of scales, and
the branched hairs of insects, would be the best of all materials
for the manufacture of felt; such is, however, not the case.

The Rotifere are very fully described, and many interesting
points of their structure and life-history elucidated. This class is

one which the author has made a special study, and the chapter

contains a selection from his numerous papers on the subject
supplemented by his more recent observations.

As might be expected, it is in the portions of the work devoted
to marine animals that this eminent sea-side naturalist gives the

bar “wd

7

most interesting details; here he is perfectly at home, and it is —

* See paper by N. Burcess, Trans. Quekett Microscopical Club, vol. i., p. 25
in which the subject of felting is very fully treated.

1874.] Notices of Books. 255

evident that the reader is under the guidance of one who is
familiar with the results of shore and dredge collecting, and long
and patient aquarium observations.

A considerable space is devoted to the structure of insects. In
remarking on their eyes and ears, the author writes: ‘It is not
impossible, judging from the great diversity which we find in the
form and structure of these and similar organs in this immense
class of beings, compared with the uniformity that prevails in the
organs of sense bestowed in ourselves and other vertebrate
animals, that a far wider sphere of perception is open to them
than to us. Perhaps conditions that are perceptible to us only
by the aid of the most delicate instruments of modern science
may be perceptible to their acute faculties, and may govern their
instinéts and actions. Among such we may mention, con-
jecturally, the comparative moisture or dryness of the atmosphere,
delicate changes in its temperature, in its density, the presence
of gaseous exhalations, the proximity of solid bodies indicated
by subtle vibrations of the air, the height above the earth at
which flight is performed, measured barometrically, the various
electrical conditions of the atmosphere ; and perhaps many other
physical qualities which cannot be classed under sight, smell,
taste, or touch, and which may be altogether imperceptible, and
therefore altogether inconceivable by us.”’

It is to be regretted that the author should have contented
himself with borrowing a cut on page 151, representing the
proboscis of the blow-fly, instead of supplying a figure more in
accordance with recent observations drawn by himself.

The work can be safely recommended as a guide to those
really in earnest as to their microscopical studies, and will prove
an admirable companion to those who take their microscopes to
the sea-side during the approaching summer holidays.

A Handbook of Practical Telegraphy. By R.S. CuLttey, Member
Inst. C.E., Engineer-in-Chief of Telegraphs to the Post-
Office. Adopted by the Post-Office and by the Department
of Telegraphs for India. Sixth edition, revised and enlarged.
London: Longmans, Green, Reader, and Dyer. 1874. 8vo.,
PP- 443-

It is a sure sign of the high estimation in which Mr. Culley’s
work is held, and of the soundness of his electrical knowledge,
when we find that his volume has already reached its sixth
edition. Holding a foremost position in his profession, and sur-
rounded by the whole telegraphic network of the British Isles,
he necessarily constitutes the centre towards which a vast mass
of electrical and telegraphic information naturally concentrates ;
and, as a consequence, his writings may be considered the digest
of these experiences.

256 Notices of Books. |April,

We are informed in the preface that many portions of the’
book have been re-written,—incumbent on the author by reason
of the rapid extension of all the branches of the profession. So
numerous have been-the alterations and additions that we do not
hesitate to state that the labour of passing the book through the
press must have cost Mr. Culley great time and close application;
in fact, as much as would be necessary to compile the whole
volume. Amongst the extra matter, we find an important and
lengthy chapter on the Duplex System, which will be eagerly

read. In this chapter, the author undertakes the explanation of —

the question from the commencement; and in so clear and
popular a manner does he carry the reader along with him
through the different stages that everyone who studies the
subject can most easily follow him. There are various methods
of telegraphing by the duplex system, three of which are well
known, viz., ‘‘the Bridge,” ‘the Differential,” and ‘the
Leakage.” The two former, however, are the systems that Mr.
Culley has treated of; the third he does not refer to, because,
as we suppose, he does not consider it of sufficient practicability
to deserve attention. Students, however, we are sure, would
have been glad to have had his experience on the subject, and to
have had an explanation of the modus operandi from his pen.

The comprehension of the work is large and varied. It
includes :—

Part I., Sources of Electricity. Part II., Resistance and the
Laws of the Current. Part III., Magnetism and Electro-
Magnetism. Part IV., Induction. Part V., Atmospheric
Electricity and Earth Currents. Part VI., Insulation. Part
VII., The Construction of a Line of Telegraph. Part VIILI.,
Ordinary Testing. Part IX., Description of Instruments, ©
Part X., Submarine and Underground Wires. Addenda of
various useful tables of reference.

The same determination has guided Mr. Culley inthis asin former
editions ; he has excluded from his work all theories based upon
unproved hypotheses, and has thereby maintained its character
as a ‘¢ practical handbook” on all matters relating to the science
of telegraphy. Asa handbook it is unexceptional, and is rendered
far more readable from the profuse illustrations interspersing the
book at almost every page. Some idea may be formed of its
rich endowment in this respect, when we mention that it contains
over a hundred and fifty engravings, exclusive of nine full page
illustrations, and six large folding plates of very useful designs.
With such a work in his hands, we believe every operator on our
lines, however backward he may be in his electrical knowledge,
would soon acquire a sound acquaintance with the practice of the
science, and to them, as well as to general scientific students, we —
heartily recommend the work.

1874.] Notices of Books. 257

Student’s Class Book of Animal Physiology. By T. Austin
: Buttock, LL.D. London: Relfe Brothers.

Tue author tells us in his preface that ‘‘ This book, whatever
be its fate, has come of a careful and earnest endeavour to meet
the requirements of higher and middle class schools, and of all
teachers who may desire to prepare pupils for Government or
other science examinations.”

We quite believe in the care and earnestness of the manufacture
of this book. Every page displays the result of careful and
earnest cramming on the part of the author himself, and an
equally careful and earnest effort to transfer the cram to his
readers or pupils. The machinery by which he seeks to effect
this is a series of questions followed by mechanical answers
suitable for the requirements of those michievous people who.
call themselves teachers, and whose teaching consists in putting
certain books in the hands of their unfortunate pupils, marking
so many lines to be “ got off by heart,” and then listening to
their misguided victims while they ‘‘ say their lessons.”

The following is a sample :—

Q. What are the names and positions of the interior bodies
of the brain?”

“©A, From the base upwards we have (1.) The Posterior and
Anterior Pyramids, and quite close -by the side of the latter are
(2.) The Olivary Bodies, with the Restiform Bodies on their outer
sides; (3.) The Pons Varoli, a mass of neurine an inch wide, with
its fibres running like a bridge across the Medulla Ob.; (4.) The
Corpus Dentatum, a mass of grey neurine with a tooth-shaped
edge, in the anterior of that part of the cerebellum at the sides
of the Pons; (5.) The Crura Cerebri (legs of the brain) rounded
masses of nerve fibres, which, from the Medulla Ob., emerge at
the upper end of the Pons; (6.) The Corpora Albicantia, two
pear-shaped silvery bodies at the base of the brain, but connected
with the cerebrum; (7.) The Corpus Callosum which unites the
two hemispheres of the cerebrum; (8.) The Pituitary Bodies,
between the Olfactory Nerves; and (9,) The Tuber Cinereum
just under the latter (Fig. 25, V. between V and W; S.E.P.M.;
Corpus Callosum between I. and G.; I. K).

Fig. 25, to which these utterly unintelligible references are
made, is a representation of the exterior of the base of the brain.
The next question is—

«Q. What are the other bodies in the interior of the brain.”

This is answered in like manner by simply enumerating the
Thalami, Corpora Striata, Corpora Quadrigemina, and the
Commissures in the same parrot-like manner, and again referring
to Fig. 25, in which none of these ‘‘ Bodies”’ are shown.

_ This is all the information afforded on this part of the subject.
Anybody at all acquainted with the structure of the brain may
imagine the state of mind of the unfortunate pupil who strives to
obtain any ideas from such a string of merenames. What must

258 Notices of Books. (April,

be his notions of the anterior and posterior pyramids, of the legs
of the brain, &c.?

From this sample of anatomical exposition let us pass to one
ortwo physiological disquisitions. The following is the answer
to the question ‘‘ What is the Sensorium ?”

‘‘ That ideal point of the brain which the older physiologists,
and some modern school books, call the Sensorium, and regard
as the seat and abode of soul, is merely a fancy organ which has
no existence; but the Sensorium of modern physiologists is a
series of ganglionic centres at the base of the brain, including
the Olfactory Bulb, or ganglion, and the auditory and optic
ganglia.”

The spinal cord is described as ‘‘ the seat of a set of definite
and combined muscular movements, which are altogether
independent of sensation and volition ; and it gives to the whole
muscular mechanism a healthy contraction and tone, which at
once disappear on its destruction.”

‘‘Q. What is the reason that certain kinds of animals live in
the human stomach in spite of the powerful action of the gastric
juice?
ah A. On living substances the juice has no power, but it acts
immediately after death, and it has been found that it sometimes
dissolves and perforates the stomachs of the dead. Bone, even
iron, and other metals gradually yield to its action; and there
are instances of nails and clasped knives having been reduced to
mere fragments in the human stomach.”

Lesson 14 is headed ‘‘ Gases in Blood.” ‘The first question
of this lesson is :—‘‘ How is the colour of the blood affected by
O and CO,, and why is O constantly supplied and CO, as
constantly thrown off?” This and the next question, ‘*‘ Why
is CO, found in the blood, and how is it related to the tem-
perature of the body?” are answered as though oxygen and
carbonic acid gases are actually and abundantly mixed with
the blood ‘‘thrown off,” and circulate with it. In reply to the
question, ‘‘ What is the exact chemical composition of albuminous
substances ?” the pupil is told ‘‘that all these substances consist
of C, H, O, N, S, and that some of them possess P in addition,”
and further on, that ‘‘ gelatine consists of the same elements as
albumen, but combined in smaller proportions.” This style of
actual looseness and inaccuracy, with affected technical pro-
fundity, prevails throughout, and is calculated, even where no
actual blunders are made by the author, to convey most erroneous
ideas to the pupil.

The author, in his preface, says, ‘‘ We have dealt little in
general description, or in those ‘bird’s-eye views’ which try hard
to exhibit all, succeed well in showing nothing. A really earnest
student who prepares to meet remorseless examiners must see
the subject not in bird's-eye view but from the plane of the facts
and circumstances themselves.’ We pity any ‘earnest student”

1874.] Notices of Books. 259

who relies on this or any of the kindred works that are written
by incompetent teachers for the mere purpose of cramming with
phrases and technicalities in order to pass examinations. Inthe
learning of languages, whether living or dead, this wretched
method of packing the memory may be sufficient; but we warn
all candidates for science examinations against any attempts to
‘eet up” any branch of science by mere efforts of memory.
Something higher than this is demanded of the scientific student.
He must not merely learn his lesson,—he must understand his
subject ; for the remorseless examiner in science at once detects
the ignorance of the candidate who merely answers by rote. If
he is at all qualified to conduct a scientific examination, he will
always include among his questions some theoretical and practical
problems which ignominiously convict the crammed candidates,
and he condemns their blunders far more remorselessly than the
shortcomings of the conscientious student who has learned
much less but understands a little more. A simple rudimentary
treatise on physiology which, in the same space as the book
before us, attempted to teach conscientiously and thoroughly
about one-tenth of what is here pedantically heaped together,
might enable a student to pass some of the more elementary
examinations on physiology adapted to junior pupils; but this
** Student’s Class Book” is utterly worthless for the purpose of
the ‘‘really earnest student,” and can only serve as a delusion
and a snare even to the student who is so misguided as to
attempt to pass an examination .in physiology by merely
cramming the memory with technicalities and learned phrases.

A Treatise on Watch-Work, Past and Present. By the Rev.
H. L. Nevturopp, M.A., F.S.A. London: E. and F. N.
Spon. 1873.

LET no one suppose that it is the watch-maker alone who will
be interested in this little treatise. Indeed we doubt whether
the work will find much favour in the trade; for the reverend
writer exposes so many of the malpractices of the watch-maker’s
craft that he will probably find himself as unpopular in Clerk-
enwell as Mrs. Stowe is said to have been in the Southern
States after the publication of her anti-slavery novels.

During a century and a half, dating from about 1660, when
Dr. Robert Hooke invented and applied the balance or pendulum-
spring, the science of horology made great advances in this
country. Those were the palmy days of watch-making when
the workman took an intelligent interest in his work and sought
to gain a reputation by the quality of his escapements. But,
tempora mutantur, and at the present day our author maintains
that there is not a rising man to lay claim to the sceptre of such
makers as Mudge, Arnold, or Earnshaw, and that “in a few

260 Notices of Books. _ (April,

years it is not probable it will be possible to find in Clerkenwell
a workman capable of doing first-class work.” To remedy this
lamentable state of things, Mr. Nelthropp suggests that it would
be desirable to establish a school in connection with South Ken-
sington, and to revive, in some measure, the powers of the
Clock-makers’ Company, so that members should be elected
only after examination by a competent governing body.

Although watch-making seems to be falling into this state of
decay in England, there are yet many amateurs who take great
interest in the art. But with the exception of Mr. Denison’s
excellent ‘‘ Rudimentary Treatise,” published some years ago in
Weale’s series, we do not remember any modern English work
on this subject.

After defining the terms used in watch-work, and describing
the tools used by the watch-maker, Mr. Nelthropp presents the
reader with a sketch of the history of time-keepers. ‘ Le ciel
est une horloge constante et perpétuelle,’’ and therefore the sun-
dial was the earliest form of time-piece. As to watches, the
antiquary knows that they were first made by Peter Hele, of
Nuremberg, about the year 1500, and were called—from their
place of manufacture and from their shape—‘‘ Nuremberg eggs.”

Passing from the historical to the technical portion of the
work, we find rules for calculating the number of teeth of wheels
and leaves of pinions, and the necessary calculations for trains.
Descriptions are then given of the five principal scapements—
the verge, the horizontal, the duplex, the lever, and the detached
escapement. A translation of a treatise on the pitching of
wheels and pinions, by the astronomer M. de Lalande, is given
in the shape of an Appendix.

Although Mr. Nelthropp’s volume is not the work of a man
practically engaged in the trade, it may be recommended not
only to the antiquary who delves into the history of the watch-
maker’s craft, but also to every intelligent person who seeks to
know something about the anatomy of the little time-keeper
which he carries in his pocket.

4

1874.] ( 261 )

PROGRESS IN SCIENCE.

MINING.

Owinc to the alteration in the system of colle@ing the Mineral Statistics of
Great Britain, introduced by the new Mines’ Regulation Ads, the publication
of the last volume of Mr. Robert Hunt’s valuable Statistics, giving the
returns for 1872, was unavoidably delayed until so late in 1873 that we were
unable to notice them in the last number of this Journal. The method of
obtaining voluntary returns, originally initiated and for many years success-
fully carried out by the present Keeper of Mining Records, has been displaced
by a compulsory system, under which the returns are forwarded, through the
local Mining Inspectors, to the Secretary of State for the Home Department.
It may be well to point out that the working of this system, in its present
form, is fraught with much inconvenience. Thus, by a curious accident in
the wording of one of the clauses of the Coal Mines’ Regulation Act, no one,
except the Inspector and the Home Secretary, is permitted to see the returns,
unless express consent be given by the coal-owner. Hence the Keeper of
Mining Records himself is actually shut out, in most cases, from consulting
the very returns which it is his duty to collate and present, in an aggregated
form, to the public.

One great cause of delay in the publication of the last volume of ‘‘ Mineral
Statistics ” is attributable to the faé that, although the Metalliferous Mines’
Regulation A@, 1872, requires that all returns shall be made to the Inspectors
by the rst of August in each year, yet many of the returns on this first occa-
sion were not in the Inspector’s hands until late in November. Moreover, the
Aé& requires only a return of the ores raised, and consequently their value and
percentage of metal have to be obtained from other sources. Mr. Hunt has
therefore made use of the returns to the Stannary Court for the ores of Devon
and Cornwall, and the Public Ticketings for the copper-ores sold in Cornwall
and Swansea.

Following our usual course, we here present a general summary of the
quantity and value of the minerals raised in the United Kingdom during the
year 1872 :—

No. of Mines. Tons. Cwrts. Value.

STMT ya) <0!) fc) | Sa) se 2 5) 3007 123,497,316 o £ 46,311,143
oon One, GAS noes 266 16,584,857 0 71774874
SG! ORS 4 AGB SGN soba aac moe 117 91,983 O 443,738
OS Ge re 162 14,266 o 1,246,135
neti! 282, 2 Qe 455 83,968 3 1,146,105
Zinc ore .. BEV eoe 63 18,542 12 73,951
Tron pyrites (sulphur ore) ot MRE 35 65,916 3 39,470
ARSENIC .. . ‘ Bteate ts 15 PEG aueds 17,964
Bee CINIMM sry 'ofsy & sis ssid fehl) co's 3 88 5 993
Cobalt of TLC Ween Bis Me Ban ice I ro 20
Manganese co Pek She price 3 773110 38,865
Fluor spar. RS ese te I 80 12 40
Ochres, umbers, ‘&e. Sess Het sts 5 35320) 55 8,227
Bismuth OLE by, siz we I 250 —

Barytes and chloride of barium .. 26 0,157 17 7,208
Clays, fine and fire (estimated) .. — I,200,000 Oo 450,000
Other earthy minerals (estimated) — — 650,000
a a tia. ees 1,309,497 10 654,748
Coprolites (estimated) Se) Sele. tots — 35,000 oO 50,000

Total value of minerals produced in the United Kingdom in 1872..£58,913,541
VOL. IV. (N.S.) 2L

262 Progress in Science. (April,

Under the name of the Aérophore, M. Denayrouze has brought out an
ingenious apparatus for furnishing to the miner a supply of fresh air in the
midst of a deleterious atmosphere. The air is compressed by a double-
barrelled pump of peculiar construction, the cylinders being movable, whilst
the pistons are fixed, thus reversing the usual arrangement. By means of a
regulator the pressure of the air may be adjusted at pleasure. The miner
inhales the air through an india-rubber mouth-piece, whilst a supply is
delivered on similar principles to hislamp. The Denayrouze lamp is specially
construéed to burn independently of the surrounding atmosphere, and derives
its air solely from the lamp-regulator. In one form of the Denayrouze appa-
ratus the air is compressed into strong reservoirs, at a pressure of 20 atmo-
spheres. Experiments putting the apparatus to tests which seem to be
sufficiently severe have recently been conducted in this country,—it is said
with much success. No doubt such an apparatus might be of special service
in re-opening a pit after an explosion, and before it is expedient to admit
fresh air; but it is evident that apparatus of this kind can have but a limited
application, and is not likely to be used for prolonged work.

To prevent the collier from tampering with his Davy-lamp, Messrs. Bailey
and Waddington have patented the application of a seal to the locked lamp.
This seal is enclosed in a case, and so arranged that the miner cannot un-
screw his lamp and expose the light without breaking the seal, and thus
convicting himself.

At a recent meeting of the North Staffordshire Institute of Mining and
Mechanical Engineers, a paper was read, by Mr. T. M. Goddard, on “ Better
Communication in Pit-Signalling by means of Electricity.” He described the
system of eleGrical signalling employed with much success at the Golden-
hill Colliery. This system was said to be much more economical than the
ordinary method of using a stranded bell-wire, and not so liable to get out of
repair. Moreover, less room is required in the shaft with this system.

The subje@ of coal-cutting by machinery was recently brought before the
Cleveland Institution of Engineers, by Mr. J. S. Jeans, of Darlington. After
tracing the history of such machinery, he described two of the most popular
coal-cutters,—namely, Mr. W. Firth’s machine, and the Gartsherrie coal-
cutter of Messrs. Baird. The latter has been successfully working at the
Hetton Colliery.

‘An Essay on the Prevention of Colliery Explosions,” by Mr. Emerson
Bainbridge, of Sheffield, has appeared in the columns of the *“ Colliery
Guardian.” After enquiring into the cause of such accidents, the author
examines how far the means now used for their prevention can be considered
successful, and points out what he considers should be done by legislation
and by mining-engineers to prevent such explosions, and to lessen their fatal
effects when they do occur. Mr. Bainbridge’s experience and position should
secure a respectful attention to his views. This essay is one of those written
in competition for the Hermon prizes. The three prize-essays—those of
Mr. W. Galloway, Mr. W. Creswick, and Mr. W. Hopton—have been pub-
lished in a separate volume. Another of the competitive essays, by Mr. J.
Harrison, of Eastwood, Notts, has appeared in the *“t Mining Journal.”

An “ Official Report on the Coal-Fields of Victoria,” prepared by Mr. J.
Mackenzie, the Government Examiner of Coal-fields in New South Wales,
has been recently issued. It contains a careful description of the several
coal-deposits of the Colony, illustrated by sections, and offers suggestions
where search should and should not be made for payable seams of coal.

Mr. H. B. Medlicott has published, in the ‘‘ Memoirs of the Geological

Survey of India,’ some ‘‘ Notes on the Narbada or SatparA Coal-Basin.” It
seems probable that we have in this basin a more complete representation of —

the great plant-bearing rock-series of India than in any other part of the
Peninsula. The writer advises that the experiment of boring for coal within
the field, at a distance from the actual outcrop, should be made at Budi, in
the Dudhi Valley.

c

1874.] Metallurgy. 263

The peculiar conditions under which diamonds occur in the fields of South
Africa have been well described by Mr. E. J. Dunn, who, before his recent
return to the Cape, contributed to the Geological Society of London an inte-
resting paper on this subje@. The so-called “dry diggings,” such as the
well-known Colesberg Koppje and Du Toit’s Pan, are circular areas surrounded
by horizontal shales. As to the diamond-bearing rock itself, Mr. Dunn
describes it as an eruptive mass brought up to the surface through pipes which
have penetrated the shales, and turned up their edges. On sinking into these
pipes, the general sequence of deposits is—first, a few feet of sand; then, a
layer of calcareous tufa; and this deposit passes gradually into an altered
igneous rock, the true character of which is still an enigma. It has been sug-
gested that it may be a gabbro or euphotide, serving as the base of a breccia
which contains fragments of shale, dolerite, and other rocks. Can this
euphrotide breccia be regarded as the actual mother-rock of the South-African
diamonds ?

METALLURGY.

Under the head of ‘‘ Mining”’ we publish this quarter a summary of the
‘Mineral Statistics’ for 1872, showing the quantities of ores raised in the
United Kingdom during that year. In connection with these returns, and to
show the position of our metallurgical industries, we may present the following
statement, which exhibits the quantities and values of the several metals
obtained from-the ores raised in 1872:—*

Quantity. Value.
EIPCITOMM sles sl ae) LOS! 6;741,929 £ 18,540,304
BROMMEEN (Sat tu srw sijelo) Nav 7 5,703 583,232
WIRTON en rere pTeiw, p Vicish, ie asl nf 9,560 1,459,990
Lead Scfpicich poco an rad . 60,455 1,209,115
SuUIVCIEE Tacit eo tenia | OZS.. 628/920 157,230
Zine Be a) see Paves ee, ROons 5,191 118,076
Other metals (estimated) .. — 2,500

£ 22,070,447

An interesting feature is this year introduced into the ‘‘ Mineral Statistics,”
in the shape of returns giving the consumption of coal in our blast-furnaces.
These figures show that the quantity of coal consumed, on an average, for
every ton of pig-iron produced, in 1872, amounted to 51 cwts. The economy
of our iron-masters becomes evident on remembering that it was computed by
the Royal Coal Commission that 3 tons of coal were consumed per ton of
pig-iron.

Mr. T. Hughes, of the Geological Survey of India, has contributed to a
recent number of the Survey ‘‘ Records”’ some notes on the ‘ Iron-Deposits
of Chandra in the Central Provinces,” in which he gives some interesting
details respecting the relative amounts of ore and fuel ordinarily employed by
the natives in their furnaces. The wealth of Chandra in iron ores is consider-
able, and the value of the deposits is likely to be increased by the occurrence
of coal in the neighbourhood. The native furnaces, though still liliputian, are
larger than those commonly in use in Bengal, and several attain a height of
nearly 6 feet. The section of the furnace is that of a cone; the hearth, as
usual, slopes from behind forwards; the tuyeres are each g inches long,
1} inches diameter at the larger and 2 inch at the smaller end; and the
bellows are usually worked by hand. Taking the mean of several experiments,
and reducing the weights to English units, we find that 8 tons of ore and
14; tons of charcoal are consumed in the manufacture of 1 ton of wrought-
iron by this method.

* Mineral Statistics of the United Kingdom of Great Britain and Ireland, for the Year 1872.
With an Appendix. By Rosert Hunt, F.R.S., Keeper of Mining Records. Longmans, 1873.

264 Progress in Science. April, —

The Cleveland Institution of Engineers has been lately engaged in discussing
Mr. Wood’s methods of utilising blast-furnace slag. The slag is allowed to
run from the furnace into water placed at the bottom of an iron drum rotating
in a vertical plane. By this means the slag is disintegrated, and forms a
powder called “ slag-sand,” which may be mixed with lime and used as mortar.
The slag, in another of Mr. Wood’s processes, is received on a flat, circular,
rotating table of iron, where it is suddenly cooled, and spreads out into thin
layers, which may be readily broken up and used in the preparation of con-
crete. Although there is perhaps no great novelty in Mr. Wood’s methods, —
they are nevertheless likely to be of much value in using up a great deal of
the Cleveland slag. In 1862 Mr. Gjers obtained a patent for running a stream
of slag into water, but he allowed his patent to lapse. One great feature in
Mr. Wood’s machine is its economy of water. Mr. Jeremiah Head calculated
that the cost of water would be only about th of a penny per ton of slag
disintegrated.

To determine the elasticity of metals, two different methods may be em-
ployed—either dire@& tra&tion or transverse flexion. The discrepancy in the
values obtained by these two methods in experiments with steel have been
theoretically investigated by M. Peslin, in a paper, ‘Sur la Ténacité de
l’Acier,” published in a recent number of the ‘‘ Annales des Mines.”

In connection with this subje& we may refer to a paper on ‘‘ Tests of Steel,”
by Mr. A. L. Holley, read before the American Institution of Mining
Engineers, in which the writer strongly condemns the practice of confining
ourselves to mechanical tests, and staunchly advocates that all tested samples
should be submitted to chemical analysis. In order that engineers may know
what to specify, and that manufacturers may know what to make, a knowledge
of the chemical composition of steel becomes absolutely necessary.

We observe that a paper ‘* On the Molecular Changes produced in Iron by _
Variations of Temperature,” by Prof. R. H. Thurston, of the Stevens Institute
of Technology, has been reproduced in “Iron.” :

M. Pirsch-Baudvin has patented a new alloy, said to bear a strong resem-
blance to silver in many of its physical characters. A very white metal,
forming a good imitation of silver, may be made of—Copper, 71; nickel, 16°5;
cobalt, 1°75; tin, 2°5; iron, 1°25}; and zinc, 7: about 1°5 per cent of aluminium
may be added. In the preparation of this alloy certain precautions are neces-
sary in the order and manner in which the constituents are mixed. The ©
cobalt is said to determine many of the characters of this alloy.

The well-known ‘ Revue Universelle des Mines, de la Métallurgie, des
Travaux Publies, des Sciences, et des Arts appliqués a l’Industrie”’ is about to
appear in an English dress. The proprietors have arranged for an English
translation of each number, which will appear almost simultaneously with the
French edition. This ‘* Review” has recently contained a capital Report of
the Liége Meeting of the Iron and Steel Institute.

MINERALOGY.

Corundum has been discovered, within the last two or three years, in
deposits of considerable extent, and under conditions of unusual interest, at a
locality, now known as Corundum Hill, in Macon County, North Carolina.
Colonel Jenks, who discovered these deposits and has established workings
for corundum at the Culsagee Mine, has recently visited this country, bringing
with him a collection of specimens of great beauty and scientific interest.
These have been submitted to the Geological Society, accompanied by notes
on their mode of occurrence. It appears that the corundum is found in veins
in a hill of serpentine, and is largely associated with chloritic minerals, such
as ripidolite and jefferisite. Some of the crystals are notable for the intimate
manner in which they are blended with these minerals, whilst others exhibit
such brilliancy as to suggest that but little more is needed, in the way of purity
of colour and freedom from flaws, to transfer them to the category of true
gem-stones. It is hardly too much to expea& that sapphires, rubies, and the

1874.1] Mineralogy. 265

other valuable forms of alumina, may be yielded by the further working of
these deposits. We understand that some of the crystals have been examined
microscopically by Mr. H. C. Sorby.

For several years past Dr. F. A. Genth has devoted much attention to the
study of Corundum, especially noting the characters of the associated minerals
and the changes which corundum is supposed to undergo. ‘The results of his
studies have been published in theshape of the first part of the ‘* Contributions
from the Laboratory of the University of Pennsylvania.’? Although corundum
has been found in America both in the Laurentian system and in rocks
referred to the Taconic system, yet the greater part of the American corundum
occurs in what is termed the chromiferous serpentine or chrysolite formation,
and in the adjacent rocks. By comparing the associated minerals and the
general conditions of occurrence of the emery and corundum of Asia Minor
and the Grecian Archipelago with those of the most important American
deposits, Dr. Genth is led to suggest a correspondence of geological age in
the two cases. The author gives a long catalogue of minerals supposed to be
produced by the alteration of corundum, and refers in some instances to true
pseudomorphs as evidence of suchchanges, There are probably few geologists,
however, who will be prepared to receive Dr. Genth’s theory which seeks to
explain the origin of certain beds of mica-schist, chlorite-schist, and paragonite-
slate, by the alteration of larger deposits of corundum. Among the minerals
associated with the American corundum are four described as new species, or
varieties, under the names of Dudleyite, Kerrite, Maconite, and Willcoxite.

Dr. Fischer, well known for his microscopic studies of various minerals, has
examined a number of specimens of so-called Cat’s-eye ; that is to say, quartz
which presents, when polished, a curious band of light generally referred to
the presence of enclosed fibres of asbestos. In all the specimens examined
by Fischer he could find no trace of any fibres of asbestos, so that we are
compelled to seek a new explanation of the fibrous character of the cat’s-eye.
The quartz may either possess a true fibrous structure of its own, or it may
have replaced some mineral which originally possessed such a structure. It
is the latter conclusion that Dr. Fischer is disposed to accept. This conclusion
is interesting in connection with Wibel’s examination of the cat’s-eye of the
Cape, noticed in last quarter’s chronicles. Fischer’s paper will be found in
Tschermak’s ‘‘ Mineralogische Mittheilungen,” published in Vienna.

A new mineral-species belonging to the group of felspars has been lately
described by Von Kobell, in the ‘* Journal fur Praktische Chemie,” under the
name of Tschermakite,a name proposed in honour of Dr. Tschermak, who
has done so much to simplify our views of this important group of rock-
forming minerals. Tschermakite occurs at Bamle, in Norway, where it is
associated with Kjerulfine. The new species is found in compact masses,
with very perfe& cleavage in two directions, making an angle of 94°. These
cleavage-planes show fine strie, similar to those on other triclinic felspars,
Analysis gives—Silica, 66°57; alumina, 15°80; magnesia, 8-00; soda, with
trace of potash, 6°80; water, 2°70=99'87. From this analysis may be deduced
the formula -3(RO.3SiO2)+A1,03.3Si02. Tschermakite may therefore be
regarded as a peculiar species of felspar, related to oligoclase, but containing no
lime.

An excellent monograph of the minerals grouped together under the
general name of Brochantite, has been laid before the Vienna Academy. by Dr.
Schrauf, and published in its ‘“‘Sitzungsberichte.”” He describes in much
detail, and illustrates by admirable figures, the several forms of this mineral,
of which four distinét types are recognised. It appears that Brochantite is not
prismatic in crystallisation, but that most varieties are either monoclinic or
triclinic.

' The peculiar form of silica which Prof. Maskelyne some time ago discovered
in the Breitenbach meteorite, and described under the name of Asmanite, has
been recently studied by Prof. Vom Rath. His conclusions confirm those of
Maskelyne, respecting the specific gravity, degree of hardness, and chemical

266 Progress in Science. (Apri,

composition. Vom Rath’s analysis gives—Silica, 96:3; ferric oxide, 2;
magnesia, I°1; lime, trace. There seems, therefore, no doubt that Asmanite
is a new form of silica crystallising in the rhombic system, so that we are now
acquainted with three species of crystallised silica, distinguished by their
specific gravity in this wise :—

QUIATEZ 9: Bie Lahet pie ot Sela obo gf ois) une SPU
Dtdsyanite eveie aie) made) Bieta fodeedatt ote 5 2°3
ASiMaTHce ete Gwe tee tls teks tele e Rete 4 2°24

by Levy in 1824, and named in honour of Gustav Rose. It appears that only.
two specimens are known, the one in the Werner Collection at Freiberg, in ©
Saxony, and the other in the Turner Collection in this country. Both came ~
from Schneeberg, in Saxony. Two new specimens, recently found at this
locality by Herr Tréger, have been described by Prof. Weisbach.

A continuation of Rammelsberg’s researches ‘‘On the Composition of the
Natural Compounds of Tantalium and Niobium” has appeared in a recent
number of ‘‘ Poggendorff’s Annalen.”’ The present portion of the investigation
relates to the minerals called pyrochlore, yttrotantalite, fergusonite, polyclase,
euxenite, wohlerite, samarskite, and zschynite. 7

Prof. Zepharovich has presented to the Vienna Academy a further description
of his new mineral, Syngenite. He now finds that the species must be
referred to the monoclinic and not to the rhombic system; that the artificial
salt having the same composition (namely, CaSO,+Na,50,+H20) is also
monoclinic; and that Rumpfe’s mineral, Kaluszite, is in all probability identical
with syngenite.

Dr. Burkart, of Bonn, has described in Leonhard and Geinitz’s ‘**‘ Neues
Jahrbuch” the mass of meteoric iron known as the Descubridora meteorite.
This was found near Poblazon,in Mexico. The same mineralogist has a paper
on the occurrence of the various minerals of tellurium and bismuth in the ~
United States.

Among recently-published papers bearing as much on physics as on
mineralogy, we may cite a memoir by Dr. Carl Klein, of Heidelberg, on the
optical characters of the Epidote of Sulzbach; a paper by Prof. Néggerath,
of Bonn, on the phosphorescent glow exhibited by agates and other siliceous
stones when ground on the large wheels used in the polishing-mills at Oberstein

}
and Idar; and a paper by Dr. Behrens, of Kiel, on the spectrum of the precious
opal.

ENGINEERING—CI1VIL AND MECHANICAL.
;
s

One of the rarest known mineral-species is Roselite, a substance determined {
4
uJ

.

Boilervs.—At the present day when every manufacture is carried on with the
aid of steam, the strength of boilers is a most important question with-
reference to the duty they are expected to perform. This, as a seétion of
experimental science, has been very much neglected in this country. From
- an article which appeared in the ‘‘ Nautical Magazine,’’ on the United States
Experimental Commission, it appears that the majority of the experiments
made by Fairbairn, on the collapsing of tubes, and upon which’a rule was
based for the construction of steam-boilers, were with tubes of No. 19
wire gauge, or about j,rd of an inch in thickness. According to the
practical rule based upon these experiments, the strength against collapsing
is directly as the square of the thickness, and inversely as the length,
but the constant multiplier for collapsing pressure is given 71 per cent
above the mean of the experiments, and 25 per cent above the maximum
result obtained. Before September, 1871, Mr. Francis B. Stevens, of Hoboken,
New Jersey, had made several experiments on the strength and proper
management of boilers belonging to the United Railroad Companies of New
Jersey; and so valuable did the results appear, that the Executive
Committee of the United Companies voted 10,000 dollars for the continuance
of the experiments, which were made on real boilers and with steam-
power. The paper from which we quote was written before the com-
pletion of the experiments; but, so far as they had gone, they fully indicated

1874.] Engineering. 267

the danger produced by constructing a boiler so that the failure of any one
stay would be fatal to the whole structure; and this is the more important
since stays are seldom made to take the strain equally. The importance of
the proceedings of this Experimental Commission was considered so great
that the subject was brought before Congress, by whom 100,000 dollars have
been voted to carry out similar experiments on a larger scale, and the Com-
mission appointed for that purpose has made a beginning, but has not yet
issued its report. :

According to the report of the Midland Steam-Boiler Inspe&ion and
Insurance Company for the last half of 1873, they had 3555 boilers under
their care, and during that period there had been no explosion of any boiler
under their inspection. In consequence of the explosion of a blast-furnace
boiler, attention has been directed to the safer working of such boilers of
considerable length, it is suggested that they should be divided into separate
lengths connected with narrow necks or pipe connections so arranged as to
prevent rigidity. The feed water, in such case, would enter the back com-
partment and overflow into the next one, and then again into the front com-
partment, supposing the boiler to be in three compartments. The last
compartment alone would require a water-gauge. The water, therefore,
would gradually advance from back to front, while the heat would be greatest
in the front. In this arrangement, apart from the diminished danger of
explosion, it will be seen that the mud would be deposited in the back end,
where, the heat not being sufficient to form it into a hard scale, it could be
discharged by the blow-cock.

With regard to tube boilers, it is remarked that they can evidently be
worked with success where the high pressure for which they were designed
is required, and where good water can be obtained, but they do not offer much
advantage for low pressure, or with the average scale making water. The
experience of the past year confirms the opinion that no boiler is free from
the danger of explosion if not well looked after; and that the best means of
preventing explosion is to insist upon frequent inspection and careful attendants.

London Water Supply.—The Kent Company are now giving a constant
supply to about 2200 houses in Deptford, and is extending the constant
service to other parts of its distri. ‘The New River Company have now the
power of affording effective constant service in their district; and they have
also commenced a new high service covered reservoir, to contain one million
gallons, at Southgate, in anticipation of the requirements of the water supply
to Edmonton parish. This Company has, in a number of cases, afforded
constant supply by means of stand pipes, and have agreed with a Committee
of the Corporation of the City of London to furnish constant supply at once
to a large number of the houses of the poor within the City bounds, wherever
the arrangements of the officers of the Corporation in connection therewith
are completed. The East London Company are extending the constant
system of supply in their distri@, and have completed the arrangements for
supplying the houses in one of their distri¢ts. The Southwark and Vauxhall
Company are constructing covered service reservoirs at Nunhead, to contain
18,000,000 gallons, and are erecting additional engine power for high-pressure
constant supply. Additional boilers and works are also being constructed at
Hampton. The West Middlesex Company are giving constant supply to a
number of houses on the application of the owners, who have provided
fittings according to the Board of Trade Regulations. This Company is also
constructing extensive works and additional engine-power at Hammersmith
and at Hampton to ensure effective constant supply. The Grand Junction
Company have completed a high service reservoir near Kilburn, to contain
6,000,000 gallons for constant supply, and have laid a line of main pipes to
connec up this reservoir with the works at Campden Hill, and are likewise
erecting additional boilers and works at Hampton. The Lambeth Company
are also carrying out extensions and improvements to their Works. At
Moulsey the construétion of reservoirs is being proceeded with, to contain

268 Progress in Science. (April, |

II0,000,000 to 120,000,000 gallons of water, with pumping engines to fill

them to a level of 12 feet above the river. When full these reservoirs will

contain ten to-twelve days’ water supply to the distri. The water from the
reservoirs will run by gravitation through the new conduit to the filters at
Ditton, which are in course of extension by the conversion of the reservoirs
there into filter beds. The Chelsea Company are proceeding rapidly with the
construétion of new filter beds at Ditton, and are laying down a new 30-inch
pumping main between Kingston and Putney for the constant service supply,
besides covering in a reservoir at Putney Heath—not hitherto in use—capable
of containing 1,000,000 gallons of filtered water, to improve the supply of the
high service. :

Street Pavements.—Mr. Haywood, the Engineer and Surveyor to the Com-
missioners of Sewers of the City of London, in a recent report on the
different kinds of pavement now in use, states that, from observations taken,
it was found that, of “falls on knees,” wood pavement had the greatest pro-
portion, and that asphalt has the fewest of that class of accidents. Of falls
on haunches, the asphalt had the largest proportion, and these accidents on
it were very largely in excess of those on either of the other pavements, while
the wood had the smallest proportion. Of complete falls there were fewest
on wood and most on the granite, but the difference between the asphalt and
granite was in this respect small. - It appeared generally that horses travelling
on the wood pavement were on the whole subjected to falls of a character less
inconvenient to the general traffic in the street, and also less likely to be
injurious to the horses, than those travelling on the other two pavements, and
that in this respect the ligno-mineral was superior to the improved wood
pavement. It was also noticed that, whatever was the nature of the accident,
the horses recovered their feet more easily on wood than they did on either
asphalt or granite. On the average of the observations made, the granite
was found to be the most slippery, the asphalt the next so, and the wood the
least. The conditions of the different pavements varied, however, in some
respect with the state of the weather. Further observations than have yet
_ been taken appear necessary before any final and conclusive judgment can be
given for or against any one class of pavement.

Steam Economy.—On the 28th of January last Mr. Spence exhibited to
a distinguished audience, at Stafford House, a plan by which he proposes to
employ the heat of waste’steam as a substitute for fuel. This method is
founded upon a discovery made by the father of the inventor, that steam

liberated at atmospheric pressure, and passed into any saline solution haying —

a boiling temperature higher than that of water, would raise this saline
solution to its own boiling-point. In utilising the exhaust steam from a high-
pressure engine, Mr. Spence brings it into contacé with a solution of caustic
soda, which it will raise to a temperature of 375 degrees, or thereabouts, and
the heated solution is then circulated through pipes in an ordinary boiler, and
its heat is radiated for the purpose of generating steam in the place of heat
derived from fresh fuel. .

Brighton and Hove Gas-Works.—A paper on this subject was recently read
before the Institution of Civil Engineers, by Mr. John Birch Paddon. The
site of these works is the widest, most level, and highest part of a tra& of
shingle lying between the sea and the canal forming the eastern entrance to
Shoreham Harbour. This shingle was formerly arrested in its eastward

zy
f
i
=I
|

movement by the entrance-works to the harbour, but since the construction of

the present westerly entrance it has been greatly wasted by the sea. Between
1865 and 1870, in front of the site of the gas-works, the high-water mark ad-
vanced landwards too feet. To obtain a deposit of shingle along the sea-
front, aS a protection, two groynes were first constructed, and others were
subsequently built along the coast to be protected. The foundations of the
walls of the buildings are laid on concrete, and so extended as to make the
proportion of the weight of the superstructure to the bearing surface of
15 cwts. per square foot. The concrete bed under the retort benches is 7 feet
6 inches thick. The retort-house is 286 feet 6 inches long and 80 feet wide.

CdD Gee

1874.] Engineering. 269

The chimneys are constructed with the lower parts. of brick and the upper
parts of wrought-iron, and are sufficiently light to be placed on the benches,
so that no floor space is occupied by them: they are 71 feet 6 inches high,
3 feet square at the bottom, and 3 feet in diameter at the top, the least sec-
tional area giving 1 square inch for each lineal foot of retort—a proportion
which has proved satisfactory. There are twenty-four benches of retorts, each
bench having eight long retorts, there being two mouth-pieces to a retort, or
384 mouth-pieces in all. The retorts are cylinders, 16 inches in diameter and
20 feet long, and each retort will carbonise r ton of coal per day. Allowing
one-sixth as the number for reserve, the remainder will produce 1,500,000 cubic
feet of gas every twenty-four hours, or 300 millions per annum. The engine-
house contains four exhausters, each exhauster being driven diredtly by an
independent engine. The entire cost of the works has been about £72,000;
and when a proposed second retort-house and coal-store are erected upon the
site allotted for them, the total expenditure will amount to £100,000. The
works will then be capable of producing 600 millions cubic feet of gas per
annum, at a cost of £166 per million on the capital expended.

Concrete Blocks.—The use of concrete blocks, of large size, in the construc-
tion of marine works, has, within recent years, come to be greatly extended.
An interesting paper, ‘‘ On the Construction of Harbour and Marine Works
with Artificial Blocks of Large Size,” by Mr. B. B. Stoney, formed one of the
subjects under discussion at the Institution of Civil Engineers last February.
The author described a new method of submarine construction with blocks of
masonry, or concrete, far exceeding in bulk anything hitherto attempted.
The blocks are built in the open air, on a quay or wharf, and, after from two
to three months’ consolidation, they are lifted by a powerful pair of shear-
legs, erected on an iron barge or pontoon. When afloat, they are conveyed
to their destination in the foundations of a quay wall, breakwater, or similar
Structure, where each biock occupies several feet of the permanent work, and
reaches from the bottom to a little above low-water level. The superstructure
is afterwards built on the top of the blocks, in the usual manner. By this
method the expenses of coffer-dams, pumping, staging, and similar temporary
works are avoided, and economy and rapidity of execution are gained, as well
as massiveness of construction, so essential for works exposed to the violence
of the sea. There is now being built in this manner an extension, nearly
43 feet in height, of the North Wall Quay, in the port of Dublin. Each of
the blocks composing the lower part of the wall is 27 feet high, 21 feet 4 inches
wide at the base, 12 feet long in the direction of the wall, and weighs 350 tons.
The foundations for the blocks are excavated and levelled by means of a
divine-bell. The hull of the floating shears is rectangular in cross section,
48 feet wide, and 130 feet long. The aft end forms a tank, into which water
is pumped to balance the weight of the block suspended from the shears at
the bow of the vessel.

Dublin Water Supply.—*‘ The Water Supply of the City of Dublin” formed
the subje&@ of a paper, by Mr. Parke Neville, at the Institution of Civil
Engineers, on the 24th of February. The water supply of the City of Dublin
was for several centuries derived from the River Dodder. In 1775 this source
was found to be insufficient, and the Corporation entered into contracts with
the then Grand Canal Company for a supplemental supply, which were
extended in 1808. The water from this source was hard and subjeé to pollu-
tion, and from 1850 to 1857 the question of obtaining a better supply was
constantly under consideration. This ultimately led to the appointment of a
Royal Commission, and Sir John Hawkshaw was appointed by the Govern-
ment as Commissioner. . The result of his enquiries was the recommendation
of the River Vartry as the best source, and works for that object were com-
menced in November, 1862, and finished in 18608. The Vartry rises at the
base of the Sugar-Loaf Mountain, in the county of Wicklow, and the place
selected for the storage reservoir is near the village of Roundwood, about
7% miles below the source of the river. The embankment across the valley,
at its deepest point, is 66 feet high, and its total length is 1640 feet. The

VOL. IV. (N. S.) 2M

270 Progress in Science. (April,

greatest depth of water impounded is 60 feet, and the average depth 22 feet.
The area of the réServoir is 409 acres, and it is capable of holding 2400 million
gallons of water, equal to two hundred days’ supply for the city of Dublin and
suburbs. Two mains, 48 inches and 33 inches in diameter respectively, are
carried through the bank, in a tunnel excavated out of the rock, and arched
over. The 48-inch main, which terminates in the bye-wash, is a provision
solely for the purpose of being able rapidly to lower the water in the reservoir,
if necessary. The 33-inch main conveys the water to a circular receiving-—
basin, situated at, the outer toe of the embankment, and from this basin the
water is distributed by side canals on to seven filter-beds. After being fil-
tered, the water is colle¢ted into two pure-water tanks, from whence it is
carried for about 700 yards in an iron pipe, 42 inches in diameter, with a fall —
of 6 feet per mile, until it reaches the tunnel, into which it is laid for 120 yards, |
The tunnel is 4367 yards long, and conveys the water from the natural valley
of the Vartry, under a range of hills separating that valley from the distriés
sloping towards the sea to the east. This tunnel is from 5 feet to 6 feet high
and 4 feet wide, with a gradient of 4 feet in a mile. At Callow Hill, the
northern or Dublin end of the tunnel, there is a circular receiving-tank, ©
go feet in diameter, from which a main, 33 inches in diameter, conveys the
water to the distributing reservoir at Stillorgan a distance of 17} miles.
Three tanks relieve the pressure at different points, viz., at Kilmurray, Kil-—
croney, and Rathmichael. The water is distributed through the streets of the =

-

.

J

y

city by mains varying from 27 inches to 18 inches in diameter, which form a
zone round the central parts of the city, from which the service-mains —
diverge. Screw-valves at the intersection of the streets enable the waterto
be turned off or on, either to repair the mains or to concentrate the pressure
in case of fire. Hydrants are placed in every street at intervals of 100 yards,
and the system is so perfect that since the introduction of the Vartry water
no steam or hand fire-engine has been used to extinguish fires. The total
cost of the works has been £610,000, or at the rate of about £1 16s. 6d. per t
head of the population. ,

Great Basses Lighthouse.—In 1855 instructions were given for the prepara-_
tion of a design for the erection of a beacon on the Great Basses Rocks, off —
the coast of Ceylon. The design submitted was for a cylindrical cast-iron
tower, secured within an enlarged basement of masonry, which basement was
to be enclosed within an outer casing of cast-iron, and both tower and casing
were to be sunk into the rock. After three years’ operations, and the ex-
penditure of £40,000, only a few landings had been effected on the rock, and
the authorities therefore suspended further proceedings. In June, 1867, the
whole question was referred to the Trinity House authorities, who recom-
mended for approval a design prepared by their Engineer, Mr. J. N. Douglas,
for a granite structure in which the base of the former structure was proposed
to be utilised. The lighthouse, which has now been constructed, consists of
a cylindrical base, 30 feet in height and 32 feet in diameter, on which is placed
a tower, 67 feet 5 inches in height, 23 feet in diameter at the base, and 17 fee
in diameter at the springing of the curve of the cavetto. The thickness of
the wall is, at the base of the tower, 5 feet, and at the top 2 feet. The
accommodation within consists of six circular rooms, each 13 feet in diameter;
and there is also a room, 12 feet in diameter, in the basement, for coals and
water, and a rain-water tank below, 7 feet 6 inches in diameter. The tower
contains 12,288 cubic feet of granite, and the cylindrical base 25,077 cubic feet,
making a total of 37,365 cubic feet, weighing about 2768 tons. Above the
tower is a lantern and dioptric revolving apparatus of the first order.
cylindrical 14-feet lantern of the Trinity House has been adopted. The
dioptric apparatus has eight panels of refractors, with upper and lower prisms
for emitting flashes of red light at intervals of 45 seconds. A 5-cwt. bell, for”
a signal during foggy weather, is fixed on the lantern gallery. The cost of the
building was £64,300, and the light was first exhibited on the roth of March,
1873, and has since been regularly continued every night from sunset to”
sunrise.

*

1874.] Geology. 271

GEOLOGY.

Physical Geology.—Perhaps the most important contributions to geological
science made of late years are the observations of Mr. J. W. Judd, on the
* Ancient Volcanoes of the Highlands, and their Relations to the Mesozoic
Strata,” which he has recently communicated to the Geological Society of
London. The vestiges of the secondary strata on the west coast of Scotland
have been preserved, like the interesting relics of Pompeii, by being buried
under the products of volcanic eruptions. The deposition of these strata was
both preceded and followed by exhibitions of volcanic phenomena on the
grandest scale. The rocks forming the great plateaux of the Hebrides are
really the vestiges of innumerable lava-streams, and it is proved that these
lavas were of sub-aérial origin, by the absence of all contemporaneous inter-
bedded sedimentary rocks, by the evidently terrestrial origin of the surfaces on
which they lie, and by the intercalation among them of old soils, forests,
mud-streams, river-gravels, lake-deposits, and masses of unstratified tuffs and
ashes. Mr. Judd points out that the great accumulations of igneous
products, which in places exhibit a thickness of 2000 feet, must have been
ejected from great volcanic mountains, and in the course of his observations
he has endeavoured to determine the sites of these old volcanoes, to estimate
their dimensions, to investigate their internal structure, and to trace the history
of their formation.

Origin of Lake Basins.—Mr. J. Clifton Ward, in discussing the origin of the
basins of Derwentwater, Bassenthwaite, Buttermere, Crummock, and Lowes-
water, pointed out that they were not moraine-dammed lakes, but true rock-
basins, and, considering all the features they presented, he was of opinion that
the immediate cause of the basins was the onward movement of the old
glaciers in the neighbourhood, ploughing up their beds to the comparatively
slight depth of the basins which now form the lakes.

Geological Record.—A Record of Geological and Paleontological Literature
is being carried out under the direGtion of the British Association. It is to
embrace brief abstra¢ts of all papers published abroad or in the provinces, and
will appear regularly in the ‘‘ Geological Magazine,” after which it will be
‘issued in a separate form. Two parts appear in the February and March
numbers of the Magazine.

Mr. Whitaker has rendered great service to geologists by preparing lists of
papers published on the Geology, Mineralogy, and Paleontology of different
counties and districts. He has published those relating to Devonshire, the
Hampshire Basin, and Cambridgeshire.

Geology and Parish Boundaries.—The relation of the parish boundaries in
the south-east of England to great physical features, and particularly to the
chalk escarpment, is a subject to which attention has been called by
Mr. Topley. He has shown how the earliest settlements, and the manorial
and parochial boundaries, have been dependent upon the original state of the
country, whether wooded or open land, and upon the easily accessible water-
supply, features which are intimately connected with geological structure.

Palezontology.—Mr. Henry Woodward has described a new star-fish,
Helianthaster filiciformis, from the Devonian rocks of Harbertonford, South
Devon.

Mr. A. Wyatt Edgell has made some additions to the list of fossils from the
Budleigh-Salterton pebble-beds. These include species of Modiolopsis, San-
guinolites ?, Aviculopecten, Pterinca, Palearca, Avicula, Cleidophorus ?, Lunu-
locardium, Ctenodonta, and Orthonota? The peculiar assemblage of fossils
found in the pebbles of this triassic bed was first pointed out by Mr. Vicary,
whilst Mr. Salter assigned their parentage to beds on the coast of France.
Mr. Edgell notices the accordance between many of the pebbles of Budleigh-
Salterton and beds occurring on the opposite side of the Channel, in Brittany.
In the discussion which took place after the reading of his paper at the
Geological Society of London, Mr. Godwin-Austen observed that, in the same
manner as the shingle of Lake Superior is carried away and re-deposited by

272 Progress in Science. (April,

shore-ice, so he thought it possible that some action of the same kind might
—during a portion of the New Red Sandstone period—have drifted materials
off from the French shore of the Triassic lake, and deposited them in this”
shingle-bed at Budleigh-Salterton.

Dr. H. A. Nicholson has for some time been engaged in collecting and
studying the organic remains of the Corniferous limestone and Hamilton
formation of the western portion of the province of Ontario, which are consi-—
dered to be of Devonian age. These deposits are richly fossiliferous: the
total number of species comprised in his colletions amounts to about 160 or
170, of which between 30 and 4o are apparently new. Of this number no
less than 75 are corals, about 40 are Brachiopods, and the remainder are dis-
tributed amongst the Polyzoa, Gasteropoda, Lamellibranchiata, Annelida,
Trilobita, and Crinoidea.

Diamonds in South Africa.—The occurrence of diamonds in South Africa
has during the past few years attracted a considerable amount of public
attention. Mr.E. J. Dunn observes that they occur in peculiar circular areas,
which he regards as “ pipes,’ which formerly constituted the connection
between molten matter below and surface volcanoes. The surrounding
country consists of horizontal shales, through which these pipes ascend nearly
vertically, bending upwards the edges of the shales at the contaé. Mr. Dunn
is of opinion that the rock of the pipes was only instrumental in bringing the
diamonds to the surface, a large proportion of them being found in a frag-
mentary state. Prof. Tennant has stated that during the month of November, —
1873, no less than £100,000 worth of diamonds were brought from South
Africa by three persons. At present about twenty thousand persons are
employed in the diamond-fields, and he considers the stones equal to anyin the
world.

Sub-Wealden Exploration.—In regard to the progress of this boring, Mr.
Henry Willett reports (Feb. 12) that the new contractors (the Diamond Rock-
Boring Company) are putting forth great energy and skill in the prosecution —
of their enterprise, so as to make him very sanguine that nothing but wan
of money will prevent the exploration being extended, if found necessary, to
2000 feet. A depth of 350 feet has now been reached, and the rock there
obtained is still Kimeridge clay. We understand that Mr. W. Topley, of the
Geological Survey of England, is now resident near the spot where the boring
is being made, to examine the specimens as they are brought to the surface.

Proposed Channel Tunnel.—Mr. Prestwich has lately reviewed the geological
conditions affecting the construction of a tunnel between France and
England, which subje&, it will be remembered, was discussed not long ag
by Mr. Topley in the “Quarterly Journal of Science.” Mr. Prestwich
pointed out the geological features of all the strata between Harwich
on the one side, and between Ostend and St. Valery on the other side of the
Channel, and stated his opinion that the most feasible plan, and one that
would be perfectly pra&ticable, so far as safety from an influx of sea-water
was concerned, was to drive a tunnel through the Paleozoic rocks under the
Channel between Blanc Nez and Dover.

Geological Society of London.—At the anniversary meeting of the Geological
Society, held on February 20th, the Duke of Argyll announced the award of
the Wollaston Gold Medal to Professor Heer, of Zurich, in acknowledgmen
of his extensive researches in fossil botany and entomology. The balance of
the proceeds of the Wollaston Donation Fund was given to Dr. H. Nyst, 0
Brussels, in recognition of his admirable researches upon the Molluscan and
other fossil remains of his native country. The Murchison Medal wa
awarded to Dr. Bigsley in recognition of his long and valuable labours im
that department of geology and paleontology with which the name of
Murchison is more particularly connected. The balance of the proceeds of
the Murchison Geological Fund was divided between Mr. Ralph Tate and
Mr. Alfred Bell as a testimony of the value set by the Society upon thei
paleontological researches. John Evans, Esq., F.R.S., &c., was elected 4
President for the ensuing year.

1874.] Phystes. 273

PHYSICS.

Microscopy.— The Quekett Microscopical Club has recently been presented
with a series of insect preparations in balsam, from Ceylon. They are remark-
able, inasmuch as the usual eviscerating and laying-out processes have not
been adopted, but the insects mounted as much as possible in their natural
position, and with the minimum amount of compression: the preparations are
in many cases very thick, but this is no disadvantage, but rather the contrary,
for observations with low powers and the binocular microscope. The insects
were merely dried between the leaves of a book, and then mounted in balsam,
sometimes after a soaking in turpentine; liquor potasse has in no instance
been employed. The hardening of the balsam has been effected entirely by
exposure to the sun; the collection is totally free from milkiness from damp,
and the penetration of the balsam is perfect. This mode of preparation is, of
course, only available in tropical climates. Such preparations would probably
be best made here by drying the insects by immersion in absolute alcohol, then
soaking in oil of cloves, and, when the preparation has cleared, mounting in
balsam. This process is much used on the Continent for anatomical subjects,
frequently stained and injected, and is but little known in this country: it will
be found invaluable where other modes of drying cannot be made available.

In illustrating a paper on the ‘ Life-History of Monads,” read before the
Royal Microscopical Society, the Rev. W. H. Dallinger, F.R.M.S., executed
the drawings in a manner which rendered them available for lecture illustration
with the magic-lantern. The material chosen is finely-ground glass, upon
which the drawing is made as readily as upon paper: the camera-lucida, or
other instrument, is available for obtaining the sketch from the microscope.
The pencils used should be harder than those employed in drawing upon
paper; the engraver’s 6H will prove useful, HB being strong enough for the
deepest shadows. When the drawing is finished, it is to be rendered trans-
parent by the application of Canada balsam, thinned with benzol to the con-
sistence of cream: this is poured on the plate, and evenly distributed, some-
what in the manner of collodion in photography. When hard, the varnished
surface is protected from injury by a glass fastened on it by strips of paper
at the edges, with small pieces of card at the corners to prevent contac.
Water-colour is available upon the ground-glass surface. The process will be
found in every way easier than the usual mode of producing magic-lantern
slides, and equally effective.

The “ Sand-blast”’ process has been*successfully employed by Mr. H. F.
Hailes, of the Quekett Club, for excavating hollows in glass slides to be used
as cells. For dry mounting they answer admirably, and the roughness of the
bottom is no hindrance to mounting objects in balsam, as the lower surface of

the cell is rendered perfectly transparent by contact with the mounting
material.

Messrs. Underhill and Allen communicate to the March number of ‘‘ Science
Gossip” the following formula for glycerin jelly :—‘ Soak } oz. best amber
gelatin (as sold by the chemist or grocer) in r oz. distilled water; when it has
absorbed all the water, put it in a Florence flask with 50 grains of powdered
chloride of barium; warm it in a water-bath, and agitate till the barium salt
is dissolved. Allow it to cool below 35° C., and while still fluid add 1 oz.
of Price’s glycerin and a teaspoonful of white of egg; shake until well mixed,
replace in the water-bath, and boil at full speed until the albumen completely
separates from the jelly in the form of a single lump. Now filter through
well-washed fine flannel, and it should be as clear as crystal; but if through
Mismanagement it be a little cloudy, filter it again, this second time using
filtering-paper, and placing the funnel with the jelly, &c., in a ‘cool’ oven.
During the coagulation of the albumen, the jelly must on no account be
stirred. It is well to beat up the white of egg before use, lest it should be
stringy. The jelly made after this recipe is of the proper consistency for
entomological objects, but for delicate vegetable structures it should be softened
by adding to it a third of its volume of a mixture of equal parts of glycerin

274 Progress in Science. (April,

and distilled water. Put the jelly into test-tubes 3 inch in diameter, and when
you wish to mount a slide warm the upper part of the tube: in this way you
can pour out any quantity free from bubbles. It is perhaps well to put a trace
of varnish, or some essential oil, on the corks, lest they should get mouldy.
The chloride of barium prevents fungi in the jelly, and is the best preservative
we know of; but something is absolutely necessary. By all means avoid
putting alcohol, creosote, &c., in the jelly, as they dissolve varnishes, and also
spoil the colour of some objects.”” The hints on mounting in this paper are of
great value.

An object-glass of American manufacture has arrived in London, engraved
‘““R. B. Tolles, Boston. Immersion, 3th. 180°!! Balsam angle, 98.” It
performs well, defining splendidly, but is wanting—as are some good English
objectives—in flatness of field. Why stop at 180°? Surely an enlightened
citizen of a free and independent country will not be trammelled by the laws
of mathematics and optics.

Heat.—In a paper communicated to the Royal Society, ‘* On the Aétion
of Heat on Gravitating Masses,’ the Editor of this Journal has recorded
experiments which arose from observations made when using the vacuum-
balance, described by the author in his paper ‘‘On the Atomic weight of
Thallium,” * for weighing substances which were of a higher temperature
than the surrounding air and the weights. There appeared to be a diminution
of the force of gravitation, and experiments were instituted to render the
action more sensible, and to eliminate sources of error. After an historical
résumé of the state of our knowledge on the subject of attraction or repulsion ~
by heat, the author describes numerous forms of apparatus successively more
and more delicate, which enabled him to detect, and then to render very
sensible, an action exerted by heat on gravitating bodies, which is not due to
air-currents, or to any other known force. The following experiment with a
balance made of a straw beam with pith-ball masses at the ends enclosed in
a glass tube, and connected with a Sprengel pump, may be quoted from the
paper :—‘‘ The whole being fitted up as here shown, and the apparatus being
full of air to begin:with, I passed a spirit-flame across the lower part of the
tube at b, observing the movement by a low-power micrometer ; the pith-ball
(a, b) descended slightly, and then immediately rose to considerably above its
original position. It seemed as if the true action of the heat was one of
attraction, instantly overcome by ascending currents of air. . . . 31. In order
to apply the heat in a more regular manner, a thermometer was inserted in a
glass tube, having at its extremity a glass bulb, about 1} inches diameter; it
was filled with water, and then sealed up... . The water was kept heated to
70° C., the temperature of the laboratory being about 15°C. 32. The baro-
meter being at 767 millims., and the gauge at zero, the hot bulb was placed
beneath the pith-ball at'b. The ball rose rapidly; as soon as equilibrium was
restored, I placed the hot-water bulb above the pith-ball at a, when it rose
again, more slowly, however, than when the heat was applied beneath it.
33. The pump was set to work, and when the gauge was 147 millims. below
the barometer, the experiment was tried again; the same result, only more
feeble, was obtained. The exhaustion was continued, stopping the pump from
time to time, to observe the effect of heat, when it was seen that the effect of
the hot body regularly diminished as the rarefaction increased, until when the
gauge was about 12 millims. below the barometer the action of the hot body
was scarcly noticeable. At ro millims. below it.»was still less; whilst when
there was only a difference of 7 millims.. between the barometer and the
gauge, neither the hot-water bulb, the hot rod, nor the spirit-flame caused the
ball to move in an appreciable degree. ‘The inference was almost irresistible
that the rising of the pith was only due to currents of air, and that at this
near approach to a vacuum the residual air was too highly rarefied to have
power in its rising to overcome the inertia of the straw beam and the pith
balls. A more delicate instrument would doubtless show traces of movement

* Phil. Trans., cxliii., part 1, p. 277.

1874.] | Physics. 275

at a still nearer approach to a vacuum; but it seemed evident that when the
last trace of air had been removed from the tube surrounding the balance
(when the balance was suspended in empty space only), the pith-ball would
remain motionless wherever the hot body were applied to it. 34. I continued
exhausting. On next applying heat, the result showed that I was far from
having discovered the law governing these phenomena; the pith-ball rose
steadily, and without that hesitation which had been observed at lower rare-
factions. With the gauge 3 millims. below the barometer, the ascension of the
pith when a hot body was placed beneath it was equal to what it had been in
air of ordinary density ; whilst with the gauge and barometer level its upward
movements were not only sharper than they had been in air, but they took
place under the influence of far less heat; the finger, for example, instantly
sending the ball up to its fullest extent.” A piece of ice produced exactly the
opposite effect to a hot body. Numerous experiments are next given to prove
that the action is not due to electricity. The presence of air having so
marked an influence on the action of heat, an apparatus was fitted up in
which the source of heat (a platinum spiral rendered incandescent by
electricity) was inside the balance-tube instead of outside it as before; and
the pith-balls of the former apparatus were replaced by brass balls. By care-
ful management, and turning the tube round, the author could place the
equipoised brass pole either over, under, or at the side of the source of heat.
With this apparatus it was intended to ascertain more about the behaviour of
the balance during the progress of the exhaustion, both below and above the
point of no action, and also to ascertain the pressure corresponding with this
critical point. After describing many experiments with the ball in various
positions in respect to the incandescent spiral, and at different pressures, the
general result appeared to be expressed by the statement that the tendency
in each case was to bring the centre of gravity of the brass ball as near as
possible to the source of heat, when air of ordinary density, or even highly
rarefied, surrounded the balance. The author continues :—‘‘ 44. The pump
was then worked until the gauge had risen to 5 millims. of the barometric
height. On arranging the ball above the spiral (and making contact with the
battery), the attraction was still strong, drawing the ball downwards a
distance of 2 millims. The pump continuing to work, the gauge rose until it
was within 1 millim. of the barometer. The attraction of the hot spiral for
the ball was still evident, drawing it down when placed below it, and up when
placed above it. The movement was, however, much less decided than
before; and in spite of previous experience (33, 34) the inference was very
strong that the attraGtion would gradually diminish until the vacuum was
absolute, and that then, and not till then, the neutral point would be
reached. Within x millimetre of a vacuum there appeared to be no room for
a.change of sign. 45. The gauge rose until there was only half a millimetre
between it and the barometer. The metallic hammering heard when the
rarefaction is close upon a vacuum commenced, and the failing mercury only
occasionally took down a bubble of air. On turning on the battery current,
there was the faintest possible movement of the brass ball (towards the spiral)
in the direction of attraction. 46. The working of the pump was continued.
On next making conta& with the battery no movement could be detected.
The red-hot spiral neither attra@ed nor repelled; I had arrived at the critical
point. On looking at the gauge I saw it was level with the barometer.
47. The pump was now kept at full work for an hour. The gauge did not
Tise perceptibly, but the metallic hammer increased in sharpness, and I could
see that a bubble or two of air had been carried down. On igniting the spiral,
I saw that the critical point had been passed. The sign had changed, and the
action was faint but unmistakable repulsion. The pump was still kept. going,
and an observation was taken from time to time during several hours. The
repulsion continued to increase. The tubes of the pump were now washed
out with oil of vitriol,* and the working was continued for an hour. 48. The
action of the incandescent spiral was now found to be energetically repellent,

* This can be effeted without interfering with the exhaustion,

276 Progress in Science. (April,

whether it was placed above or below the brass ball. The fingers exerted a
repellent action, as did also a warm glass rod, a spirit-flame, and a piece of
hot copper.” In order to decide once for all whether these actions really were
due to air-currents, a form of apparatus was fitted up, which, whilst it would
settle the question indisputably, would at the same time be likely to afford
information of much interest. By chemical means a vacuum was obtained in
an apparatus so nearly perfect that it weuld not carry a current from a
Ruhmffork’s coil when connected with platinum wires sealed into the tube.
In such a vacuum the repulsion by heat is decided and energetic. An experi-
ment is next described, in which the rays of the sun, and then the different
portions of the solar spectrum, are projected into the delicately suspended
pith-ball balance. In vacuo the repulsion is so strong as to cause danger to
the apparatus, and resembles that which would be produced by the physical
impact of a material body. Experiments are next described in which various
substances are used as the gravitating masses. Amongst these are ivory,
brass, pith, platinum, gilt pith, silver, bismuth, selenium, copper, mica
(horizontal and vertical), charcoal, &c. The behaviour of a glass beam with
glass ends in a chemical vacuum, and at lower exhaustion, is next accurately
examined, when heat is applied in different ways. On suspending the light
index by means of a cocoon fibre in a long glass tube, furnished with a bulb
at the end, and exhausting in various ways, the author finds that the attraction
to a hot body in air, and the repulsion from a hot body in vacuo, are very
apparent. Speaking of Cavendish’s celebrated experiment, the author says
that he has experimented for some months on an apparatus of this kind, and
gives the following outline of one of the results he has obtained :—‘‘ A heavy
metallic mass, when brought near a delicately suspended light ball, attracts
or repels it under the following circumstances.

“© T, When the ball is in air of ordinary density.

a. If the mass is colder than the ball, it repels the ball.
b. If the mass is Aotter than the ball, it attracts the ball.

“TI. When the ball is in a vacuum.

a. If the mass is colder than the ball, it attracts the ball.
b. If the mass is hotter than the ball, it repels the ball.”

The author continues :—‘ The density of the medium surrounding the ball,
the material of which the ball is made, and a very slight difference between
the temperatures of the mass and the ball, exert so strong an influence over the
attraGive and repulsive force, and it has been so difficult for me to eliminate
all interfering actions of temperature, electricity, &c., that I have not yet been
able to get distiné& evidence of an independent force (not being of the nature
of heat) urging the ball and the mass together. ‘‘ Experiment has, however,
showed me that, whilst the action is in one direction in dense air, and in
the opposite direG&ion in a vacuum, there is an intermediate pressure at
which differences of temperature appear to exert little or no interfering
action. By experimenting at this critical pressure, it would seem that such
an action as was obtained by Cavendish, Reich, and Bailey, should be
rendered evident.’’ After discussing the explanations which may be given
of these actions, and showing that they cannot be due to air-currents, the
author refers to evidences of this repulsive action of heat, and attractive
action of cold, in Nature. In that portion of the sun’s radiation which is
called heat, we have the radial repulsive force possessing successive pro-
pagation required to explain the phenomena of comets and the shape and
changes of the nebula. To compare small things with great (to argue
from pieces of straw up to heavenly bodies), it is not improbable that the
attraction now shown to exist between a cold and a warm body will equally
prevail when, for the temperature of melting ice is substituted the cold of
space, for a pith ball a celestial sphere, and for an artificial vacuum a stellar
void. In the radiant molecular energy of cosmical masses may at last be
foundthat ‘‘ agent adiing constantly according to certain laws,” which Newton
held to be the cause of gravity.

1874.] Physics.

277

Messrs. Negretti and Zambra have recently communicated to the Royal
Society the description of a new Deep-sea Thermometer. For the purpose of
ascertaining the temperature of the sea at various depths, and on the bottom
itself, a peculiar thermometer was, and is, used, having its bulb protected by

an outer bulb or casing, in order that its indications may not
be vitiated by the pressure of the water at various depths,
that pressure being about 1 ton per square inch to every
800 fathoms. This thermometer, as regards the protection
of the bulb and its non-liability to be affected by pressure,
is all that can ‘e desired; but unfortunately the only ther-
mometer available for the purpose of registering temperature
and bringing those indications to the surface is that which
is commonly known as the Six’s thermometer—an in-
strument acting by means of alcohol and mercury, and having
movable indices with delicate springs of human hair tied
to them. This form of instrument registers both max-
imum and minimum temperatures, and as an ordinary
out-door thermometer it is very useful; but it is unsatis-
factory for scientific purposes, and for the obje@ which it is
now used it leaves much to be desired. Thus the alcohol
and mercury are liable to get mixed in travelling, or even by
merely holding the instrument in a horizontal position; the
indices also are liable either to slip if too free, or to stick if
too tight. A sudden jerk or concussion will also cause the
instrument to give erroneous readings, by lowering the in-
dices if the blow be downwards, or by raising them if the
blow be upwards. Besides these drawbacks, the Six’s ther-
mometer causes the observer additional anxiety on the score
of inaccuracy ; for, although we get a minimum temperature,
we are by no means sure of the point where this minimum
lies. Messrs. Negretti and Zambra have constructed an in-
strument on a plan different from that of any other self-
registering thermometers. Its construction is most novel,
and may be said to overthrow our previous ideas of handling
delicate instruments, inasmuch as its indications are only
given by upsetting the instrument. Having said this much,
it will not be very difficult to guess the action of the thermo-
meter; for it is by upsetting or throwing out the mercury
from the indicating column into a reservoir, at a particular
moment and in a particular spot, that we obtain a correct
reading of the temperature at that moment and in that spot.
The instrument has a protected bulb thermometer, like a
syphon with parallel legs, all in one piece, and having a con-
tinuous communication, as in the annexed figure. The scale
of this thermometer is pivotted on a centre, and being at-
tached in a perpendicular position to a simple apparatus
(presently described), is lowered to any depth that may be
desired. In its descent the thermometer aéts as an ordinary
instrument, the mercury rising or falling according to the
temperature of the stratum through which it passes; but so
soon as the descent ceases, and a reverse motion is given to
the line, so as to pull the thermometer to the surface, the
instrument turns once on its centre, first bulb uppermost, and
afterwards bulb downwards. This causesthe mercury, which
was in the left-hand column, first to pass into the dilated
syphon bend at the top, and thence into the right-hand tube,
where it remains, indicating on a graduated scale the exact
‘temperature at the time it was turned over. The woodcut
shows the position of the mercury after the instrument has
been thus turned on its centre. A is the bulb; B the outer

LONDON

& ZAMBRA
|
{=

ese

Piya

NGEGa Essent

ati

ttt

coating or protecting cylinder; c is the space of rarefied air, which is reduced
if the outer casing be compressed ; p is a small glass plug, on the principle of

VOL. Iv. (N.S.)

2N

278 Progress in Science. [April, |

Negretti and Zambra’s patent maximum thermometer, which cuts off, in the
moment of turning, the mercury in the column from that of the bulb in
the tube, thereby ensuring that none but the mercury in the tube can be
transferred into the indicating column; E is an enlargement made in the
bend, so as to enable the mercury to pass quickly from one tube to another

in revolving; and F is the indicating tube, or thermometer proper. In its t
action, as soon as the thermometer is put in motion, and immediately the
tube has acquired a slightly oblique position, the mercury breaks off at
the point p, runs into the curved and enlarged portion E, and eventually
falls into the tube F, when this tube resumes its original perpendicular
position. The contrivance for turning the thermometer over may be
described as a short length of wood or metal having attached to it a small :
rudder or fan: this fan is placed on a pivot in connection with a second; on
the centre of this is fixed the thermometer. The fan or rudder points up-
wards in its descent through the water, and necessarily reverses its position
in ascending. This simple motion, or half-turn of the rudder, gives a whole —
turn to the thermometer, and has been found very effective. Various other —
methods may be used for turning the thermometer, such as a simple pulley —
with a weight which might be released on touching the bottom, ora small —
vertical propeller which would revolve in passing through the water. Messrs,
Negretti and Zambra have also adopted a very simple and inexpensive clock- —
work to their thermometer, and by these means an observer may have a record
of the exact temperature at any hour of the day or night. We need hardly ©
say of what utility the instrument will prove to meteorologists, and even —
manufacturers, to whom an exact record of temperature is of importance. {
Hitherto we have had no simple and inexpensive instrument adapted for this
purpose: the thermograph in use at most observatories is an elaborate and
expensive apparatus, which, in connection with photography, will record on
paper the temperature during day or night; it necessitates the use of gas, or
any artificial light, and of course is only available to persons who can have a
building specially adapted for it.

ELEctTrRIcITY.—At a recent meeting of the Manchester Literary and
Philosophical Society Professor Osborne Reynolds, M.A., read a paper “ On the
Bursting of Trees and Objects struck by Lightning.” In a previous paper on
this subject he stated that the tube which was burst by a discharge from a
jar would probably withstand an internal pressure from 2 to 5 tons on the
square inch; and he made use of the expression the tube might be fired like
a gun without bursting. These statements were based on the calculated
strength of the tube, and with a view to show that there was no mistake, the
author tried it in the following manner:—He made three guns of the same
tube. No. 1, which was 6 inches long, had its end stopped with a brass plug
containing the fuze hole. Nos. 2 and 3 were 6 inches long, and had their
breeches drawn down so as only to leave a fuze hole. These tubes were
loaded with gunpowder and shotted with slugs of wire which fitted them,
and which were all 3? inch long. No. 1 was first fired with } inch of powder,
the shot penetrated } inch into a deal board, and the gun was uninjured.
No 2. was then fired with 1} inches of powder, and the shot went through the
1 inch deal board and } inch into some mahogany behind, thus penetratin
altogether 1} inches; the tube, however, was burst to fragments. Some at
these were recovered, and although they were small they did not show cracks”
and signs of crushing like those from the electrical fracture. No. 3 was then
fired with ? inch of powder, and the shot penetrated } inch into the deal
board. It was again fired with 1 inch of powder, and the shot penetrated
1 inch into the deal. Again it was a third time fired with 1} inches of powder,
when it burst, and the shot only just dented the wood. These experiments:
seem to prove conclusively the great strength of the tube and the enormous
bursting force of the electrical discharge.

At the first meeting of the Physical Society of London the Chairman (Dr.
Gladstone, F.R.S.) gave a brief description of the objects and organisation of
the Society, and announced that ninety-nine gentlemen had already expressed
their desire to join the Society as original members.

1874.] Physics. 279

Mr. J. A. Fleming, B.Sc., read a paper on the “Contact Theory of the
Battery.” After discussing the most recent views regarding the conta& and
chemical theories, Mr. Fleming exhibited the action of his new battery, in
which metallic contact of dissimilar metals is completely avoided. The
battery consisted of thirty test-tubes of dilute nitric acid alternating with the
same number of tubes of pentasulphide of sodium, all well insulated. Bent
strips of alternate lead and copper connected the neighbouring tubes. By this
device the terminal poles are of the same metal. On connecting with a
coarse galvanometer, the needle was violently and permanently deflected.
Tested by the quadrant electrometer, the potential was shown to increase
regularly with the number of cells. The sixty cells on first immersion showed
a potential exceeding that of 14 Daniell’s cells. The principle upon which
the action depends is that, in the acid, lead is positive to copper; in the sul-
phide it is negative. Mr. Fleming further showed how, by using the single
liquid, nitric acid, and the single metal, iron, a single battery could be con-
structed, provided one-half of each iron strip were rendered passive. In
this form, also, no metallic conta& occurred.

Prof. F. Guthrie exhibited experiments illustrating the distribution of a
galvanic current on entering and leaving a conducting medium. This was
shown in the case of solids by the stratification of iron-filings on sheets of
copper and lead. The effect of the distribution on a'magnetic needle which
is hung near a condu@ting vertical sheet in the magnetic meridian—into the
upper horizontal edge of which a current enters, and out of which it passes
at the same elevation—is to alter the direction of the needle’s direction of
turning, according as the needle is lowered or raised. At a distance from the
upper edge of one-third the distance of the interval between the poles, the
needle is at rest. A similar effect was shown in a liquid conductor.

The following are the officers of the Society for the first Session :—President,
J. H. Gladstone, Ph.D., F.R.S. Vice-Presidents, Prof W. G. Adams, F.R.S.;
Prof. G. C. Foster, F.R.S. Secretaries, Prof. E. Atkinson, Ph.D., York Town,
Surrey; Prof. A. W. Reinold, M.A., Royal Naval College, Greenwich.
Treasurer, Prof. E. Atkinson, Ph.D. Demonstrator, Prof. Frederick Guthrie.
Other Members of the Council, W. Crookes, F.R.S.; Prof. A. Dupré; Prof.
T. M. Goodeve, M.A.; Prof. O. Henrici; B. Loewy; E. J. Mills, D.Sc. ;
H. Sprengel, Ph.D.

Dr. Geissler, of Bonn, Germany, whose name is inseparably associated
with some of the most beautiful experiments that can be performed
by the agency of electricity, makes an electrical vacuum tube that may be
lighted without either induction coil or frictional machine. It consists of a
tube an inch or so in diameter, filled with air as dry as can be obtained, and
hermeticaliy sealed after the introduction of a smaller exhausted tube. If
this outward tube be rubbed with a piece of flannel, or any of the furs gene-
rally used in exciting the electrophorus, the inner tube will be illumined with
flashes of mellow light. The light is faint at first, but gradually becomes
brighter and softer. It is momentary in duration; but if the tube be rapidly
frictioned, an optical delusion will render it continuous. If the operator have
at his disposal a piece of vulcanite, previously excited, he may, after educing
signs of electrical excitement within the tube, entirely dispense with the use
of his flannel or fur. This will be found to minister very much to his personal
€ase and comfort. He may continue the experiments, and with enhanced
effect, by moving the sheet of vulcanite rapidly up and downat a slight distance
from the tube. This beautiful phenomenon is an effec of indudtion.

In a note on a remarkable production of light in grinding of hard stones,
Dr. Noéggerath refers to a visit made to some agate works at Oberstein
and Idar, in which various kinds of hard stone are pressed by the
workmen (with their hands) against quickly-revolving grindstones. The
transparent stones become pervaded throughout with a yellowish-red light,
like that of red-hot iron. Opaque stones give a red light at the place of con-
tact, with halo and sparks. Dr. Noggerath thinks the phenomena worth

280 Progress in Science. (April,

studying by physicists, especially as regards development of heat and
electricity.

In some researches on change in pitch of tones through movement of the
source of sound, and determination, by this means of the velocity of sound,
Dr. Schiingel experimented with two tuning forks, No. 1 giving 512, and No. 2
508 vibrations in a second, Sounded together they gave four beats in a
second. But suppose No. 2 moved towards the observer (situated beside
No. 1), its quantity of vibrations would be increased and the number of beats
diminished. Dr. Schiingel sought to measure—(z) the time in which a certain
number of successive beats was audible; and (2) the velocity of the moved
fork. His apparatus (which was eleGrical) may be briefly described :—A
seconds pendulum at each swing closed a circuit, which, through a relay,
caused a series of dots to be marked on a telegraph strip at intervals cor-
responding to seconds. By pressing a key another battery circuit could be
closed, which had two effects: part of the current went to the relay, and pro-
duced a line in the telegraph paper so long as the key was held down ; but the
greater part went through an eleétro-magnet, which attracted an armature at
one end of a lever, having at its other end a roller rotated by a cord from a
fly-wheel. The roller was thus pressed against the edge of a disc, which, thus
set in motion, wound in, by a cord about its axis, a little wagon bearing the
tuning fork (No. 2) with its case towards the observer. The method, with
some suggested modifications, is commended to the attention of physicists
for an accurate determination of the velocity of sound.

TECHNOLOGY.

Count Sokolnicki, a proprietor of vineyards at Medoc, states that a chemist,
so-called, is selling to the wine-forgers of the Gironde a liquid of which a few
drops suffice to coloura wine. An cenanthic liquor, simulating the bouquet
of Medocs, is sold openly at Bordeaux. A solution of sugar is allowed to
ferment on the pressed grapes, the colour and the flavour are added, and with
these materials wines of the best growths are counterfeited.

For the manufacture of permanent beer M. Pasteur recommends the use of
a pure yeast,—the mode of preparing which he does not describe,—free from
vibriones, baéteria, Mycoderma aceti, &c. With such yeast, the process of
fermentation can be carried on in the absence of air, or in the presence only
of limited quantities of pure air. Beers thus made can, he declares, be pre-
served for an indefinite length of time, even at temperatures of 20° to 25° C.

M. Paul has effected an improvement in photo-lithography. He produces a
positive image on paper covered with a layer of albumen mixed with a con-
centrated solution of bichromate of potash. After a sufficient insolation
under the negative, the paper is covered with lithographic ink, and then im-
mersed in cold water to dissolve the unaltered albumen.

As a test for the colouring matter of wines, M. de Cherville gives the fol-
lowing process:—Pour into a glass a small quantity of the wine under
examination, and dissolve in it a morsel of potassa. If there is no deposit,
and if the wine takes a greenish tint, it has not been artificially coloured. If
a violet deposit has been formed, the wine has been coloured with elderberries
or mulberries; if the deposit is red, beet-root or peach-wood has been used;
and if violet-red, logwood. If the sediment is violet-blue, privet berries have
been employed; and if a bright violet, litmus.

A paper ‘*On Coloured Tapers,” by Mr. James MacFarlane, Assistant to
the Professor of Chemistry, St. Andrews, was recently read before the
Chemical Section of the Glasgow Philosophical Society. The author detailed
a series of experiments which he had prosecuted for the purpose of deter-
mining the nature of the colouring matter in the green and red wax tapers.
He distinétly ascertained that the former owed their colour to the presence of
Scheele’s green (arsenite of copper). Their average weight was 2 grms., and
the average time occupied in burning was seventeen minutes. Guided by the

Rp tS

1874.] Technology. 281

colour and by the alliaceous odour evolved during combustion, he had no dif-
ficulty in pronouncing that arsenic was present; its presence was experi-
mentally determined, and its quantity estimated to be o-6o0 per cent of the
taper, equal to 0°35 grm., or 5°43 grs. of arsenious acid—quite enough to
poison two people if taken directly in the solid form. The red tapers weighed,
on an average, about 8-94 grms., and burned seventeen minutes, leaving
3 milligrms. of ash totally devoid of metallic appearance. Mercury, existing
as vermillion, was found by Reinsch’s process, and its quantity was afterwards
carefully determined. The amount of mercuric sulphide ultimately colle@ed,
washed, and dried, was 1°66 per cent. In one series of experiments the fol-
lowing results were arrived at—white, yellow, blue, red, and green tapers,
being experimented upon :—

White.—Perfe@ly harmless; little ash.

Yellow.—Harmless ; coloured with chromate of lead; ash, metallic.

Blue.—Harmless; coloured with ultramarine.

Red.—Highly poisonous, containing 1°93 per cent of vermillion; the tapers

very highly coloured ; slight ash.
Green.—Poisonous ; colour due to arsenic ; metallic ash ; quantity of arsenic
not determined, but probably about 1 per cent.

These tapers burned, on an average, twelve minutes, and in number and
quality were much superior to the first, which were of the spiral character.
The table is a summary of the results of the examination of the spiral tapers.
The author afterwards proceeded to consider the effe&t arising, or which might
arise, from the use of coloured wax tapers, and the inhalation of the vapours
resulting from their combustion.

Red. Green.
Time occupied in burning... .. .. .. «I2mins. 17 mins.
\WGIEIE 56) G8" “ean “Saad: Mode wee somlOMsE ped guts 2 grms.
ELCeMtAgelOR WAX arlene 72500 71°30
Retcentage Of Wicks js es ee sees | 25°44: 26°89
Weight of wax, pertaper..°.. .. .. 24°85 22°53
Weight of wick, pertaper.. .. .. . 8°67 8°49
Percentage of arsenious acid .. .. .. 1°81

Percentage of vermillion .. .. .. .. 1°66 to 1°93 —

The, same author submitted a communication on arsenical papers, in the
course of which he reviewed the theories and cases for and against the alleged
unhealthiness of rooms papered with hangings having Scheele’s green as one
of their colouring matters. He mentioned several cases of severe illness, and
even of death, distin@tly traceable to the inhalation of the green arsenical
compound used in the preparation of the cheaper kinds of paper-hangings.

Referring to the opinion expressed by Mr. S. Barber on page 36 of the
“ Quarterly Journal of Science,” for January, 1874, that mock suns outside
the sun are an unusual phenomenon, Mr. T. W. Backhouse writes to say this is
not the case, and that Flammarion’s book, ‘“‘ The Atmosphere,” states that mock
suns are only on the halo when the sun is low, and that as its altitude
increases they gradually emerge from it. With reference to the halo of go°,
which Mr. Barber says he believes is not seen in summer, our correspondent
Says that, if the halo about go° im diameter is alluded to, he has seen it
in summer, viz., in 1869, on June 11th and on August roth. Both these days
were, however, cool, with a maximum temperature of 58°.

( 282 ) [April,

LIST OF PUBLICATIONS AND PERIODICALS RECEIVED
FOR REVIEW.

Cholera: how to Avoid and Treat it. By Henry Blane, M.D., M.R.C.S.
Henry S. King and Co.

Catalogue of Stars observed at the United States Naval Observatory during
the Years 1845 to 1871. Prepared by Prof. M. Varnall, U.S.N.
Washington : 1873.

Treatise on Pra¢tical, Solid, or Descriptive Geometry. By W. T. Pierce.
Longmans and Co.

The Naturalist in Nicaragua. By Thomas Belt, F.G.S. Fohn Murray.
Personal Recollections, from Early Life to Old Age, of Mary Somerville. By
her Daughter, Martha Somerville. Fohn Murray.

The Galvanometer and its Uses: a Manual for Ele@ricians and Students.
By C. H. Haskins. New York: D. Van Nostrand.

Relique Aquitanice ; being Contributions to the Archeology and Paleontology
of Périgord and the Adjoining Provinces of Southern France. By
Edouard Lartet and Henry Christy. Edited by Thomas Rupert Jones,
F.R.S., &c. Williams and Norgate.

Hydraulics of Great Rivers: the Parana, the Uruguay, and the La Plata
Estuary. By J. J. Révy, Memb. Inst. C.E., Vienna and London.
E. and F. N. Spon.

Substance of the Work entitled “ Fruits and Farinacea the Proper Food of

Man. Edited by Emeritus Prof. F. W. Newman. F. Pitman.
Our Ironclads and Merchant-Ships. By Rear-Admiral E. Gardiner Fish-
bourne, C.B. E. and F. N. Spon.

The Nature and Formation of Flint and Allied Bodies. By M. Hawkins
Johnson, F.G.S.

Legal Responsibility in Old Age. By George M. Beard, A.M., M.D.
New York: T. L. Clacher.

An Elementary Treatise on Steam. By John Perry, B.E.
Macmillan and Co.

The Psychology of Scepticism and Phenomenalism. By James Andrews.
Glasgow: $. Maclehose.

Principles of Mental Physiology, with their Applications to the Training and
Discipline of the Mind and the Study of its Morbid Conditions. By

W. B. Carpenter, M.D., LL.D., F.R.S., &c. Henry S. King and Co.
Handbook of Natural Philosophy. By Dionysius Lardner, D.C.L. Edited
by Benjamin Loewy, F.R.G.S. Lockwood and Co.

Inklings of Aérial Autonometry. By William Houlston.
Simpkin, Marshall, and Co.

The Induétion of Sleep and Insensibility to Pain, by the Self-Administration
of Anesthetics. By J. M. Crombie, M.A., M.D, F.and A. Churchill.

Elements of Physical Manipulation. By Edward C. Pickering. Part I.
: Macmillan and Co.

Principles of Mechanics. By T. M. Goodeve, M.A. Longmans and Co.

1874.) ( 283 )
Cremation: the Treatment of the Body after Death. By Sir Henry Thomp-
son, F.R.C.S., M.B., &c. Henry S. King and Co.

The Universe and the Coming Transits. By Richard A. Prog@or, B.A.
Longmans and Co.

PERIODICALS.
Macmillan’s Magazine.

Naval Science.

The Popular Science Review.
The Geological Magazine.
The American Chemist.

The Westminster Review.

PROCEEDINGS OF LEARNED SOCIETIES, &c.

Annual Report of the Board of Regents of the Smithsonian Institution, 1873.
Proceedings of the Literary and Philosophical Society of Liverpool.

Monthly Notices of the Royal Astronomical Society.

Monthly Microscopical Journal.

Proceedings of the Royal Society.

NOTICE TO AUTHORS.

*.* Authors of ORIGINAL PAPERS wishing REPRINTS for
private circulation may have them on application to the
Printer of the Journal, 3, Horse-Shoe Court, Ludgate Hill,
E.C., at a fixed charge of 30s. per sheet per 100 copies,
including COLOURED WRAPPER and TITLE-PAGE; but such
Reprints will not be delivered to Contributors till ONE MONTH
after publication of the Number containing their Paper, and the
Reprints must be ordered when the proof is returned.

CASES FOR BINDING the ‘‘ Quarterly Journal of Science”
may be had, Price Is. 6d, post free 1s. 8d., from the Publisher,
3, Horse-Shoe Court, Ludgate Hill, E.C. é

; Nelthropp’ s ‘ Treatise on Watch-work.”

~

CONTENTS OF No. XLII.

Wp T he Flint and Chert Implements F ound i in Kent's Cav :
near Torquay, Devonshire. — , i atom
II. Recent Extraordinary Oscillations of the Waters i in nL
Ontario and the Sea Shores of Peru, Australia,
shire, Cornwall, &c. Bie:
III. The Native Copper Mines of Lake Superior. ie i
IV. The Modern ig eae of Atomic Matterand é uminiferou
Ether. : otom 7
V. Exhibition in Manchester of Apia for te
and Economical Use of Fuel. 2
VI. An Investigation of the Number of Constituen
and Minors of a Determinant. :

NOTICES OF SCIENTIFIC WORKS.
St. Clair’s ‘“‘ Darwinism and Design; or Creation by Evoluti
Stewart’s ‘“* The Conservation of Energy.”
Ribot’s ‘‘ Contemporary English Psychology.” _ ges aa
Pettigrew’s “ Animal Locomotion; or Walking, Swimmingvand Fyn
Smith’s ‘ Fruits and Farinacea ; ‘the Proper Food of Man.” Si
Geikie’s ** Geology.”
Marshall's as Phrenologist Amongst the Todas, or
. Primitive Tribe in South India; History, Chara
e Religion, Infanticide, Polyandry, Langua uage.
Jordan’s ‘The Ocean; its Tides and Currents, an their Caus
Alleyne Nicholson’s “Outlines of Natural Fissboty for a
Rodwell’s “‘ The Birth of Chemistry.” De eae
Winslow's “Manual of Lunacy.” |
Armstrong’s “ Introduétion to the Study of ae
Miller’s ‘*‘ Elements of Chemistry.” > aaa
Kirkaldy’s ‘‘ Results of an Experimental Enquiry into the Lechanic
-” Property of Steel Manufaétured by Charles As ae
Davies’s ‘“‘ The Preparation and Mounting of Microscoy bjects.
Lankester’s ‘‘ Half Hours with the Microscope.”
Gosse’s ‘‘Evenings at the Microscope, or Resea
Minuter Organs and Forms of Animal Life.”
Culley’s “‘ Handbook of Praétical Telegraphy.” s ee
Bullock’s ‘*Student’s Class Book of Animal ‘Physiology. at

: 25 v are

7 :

PROGRESS IN SCIENCE,

(Including the Proceedings of Learned Societies ut Home and Abroa d, d, ar
Notices of Recent Scientific Literature ae —

oo a
, oo
I

—
Suan
7

THE QUARTERLY

OURNAL OF SCIENCE,

4 4 : ie:

Ce
ei

AND ANNALS OF |

MANUFACTURES, AND TECHNOLOGY.

J

Seen BY

eel TM CROOKES, BURRS 26 k0eG

‘No. XLIII.

foe er ae. eaee pat

Communications Se the Editor and Books for Review may be addressed.
oS aoe Paris : Leipzig :
FRI RIEDRICH -KLINCKSIECK. ALFONS DURR.
—- £96 3-0-—
PRICE FIVE SHILLINGS.

[The Copyright of Articles in this Yournal is Reserved.]

SONDGENTS OF No. XLITE

Arr. PAGE
I. THe PoLe STAR AND THE Pointers. By Lieut.-Colonel
A. W. Drayson, R.A., F.R.A.S. . : ‘ ‘ 2285
Mo reser Bocs. By G. BH. Kinahan, M.R.1.4., &c. : 2) 204
III. Tue Past History oF our Moon. By Richard A.
Proctor, BA. ‘ : ; - : : ‘ - 306
IV. Moprern RESEARCHES IN TROPICAL ZOOLOGY. : a Bi71o)
V. ANNUAL INTERNATIONAL ExuiBiTions. By F.C. Danvers,
Assoc: Inst. C.E. ” . : : 2 : : - aa
VI. Tue Iowa anv Itiinois TornapDo oF May 22, 1873. By
James Mackintosh, M.A. ; : 3 : 3 330
NOTICES OF SCIENTIFIC’ WORKS:
Perry’s ‘“‘An Elementary Treatise on Steam” : ‘ : - 395
Fishbourne’s ‘‘Our Ironclads and Merchant Ships” . : 3-590
Pierce’s “‘ Practical Solid or Descriptive Geometry” . : 397

Kirkaldy’s ‘Results of an Experimental Enquiry into the

Mechanical Properties of Steel of Different Degrees of

Hardness, under Various Conditiens” . ‘ - 398

CONTENTS.

Baird’s “Annual Record of Science and Industry for 1873” - 398
Beard’s “‘ Legal Responsibility in Old Age” . : : : - 400

Timbs’s ‘ The Year Book of Facts in Science and Art”. . Bes

Maunder’s ‘The Treasury of Natural History, or a Popular
Dictionary of Zoology”’. : : 4 : : - 404

‘‘ United States Commission on Fish and Fisheries” . : » 405

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THE QUARTERLY

BOURNAL OF SCIENCE.

JULY.) 2874:

Pe tae POLE STAR AND THE POINTERS.
fy Lieut.-Colonel A. W. Drayson,’ K.A., “F.R.A-S.

Ne every educated person is sufficiently ac-
quainted with the familiar objects in the heavens to
be able to recognise the constellation known as the

“creat bear.” Two stars of this constellation are termed
“the pointers,’ because they point towards a third star
called the “‘ pole star.” The great bear, the pointers, and
the pole star may therefore be called well-known objects ;
for as these stars always remain above the horizon in our
latitude, they may be seen every clear night throughout the
year.

Among the hundreds of thousands of persons who look:at
the pole star and the pointers, probably a hundred times a
year, we have hitherto found only about four who have re-
marked a singular and interesting fact connected with these
objects. When, however, we have pointed out the inte-
resting fact, then many persons have asserted that they had
noticed the peculiarity we referred to, but that want of con-
fidence in their own observational powers had caused them
to conclude that what they fancied they saw was an optical
delusion, and not an actual fact. Results, however, of a
valuable kind emanate from the peculiarity we shall here
refer to; and though in the present article we are compelled
to treat the subject in a somewhat popular or superficial
manner, it is yet connected with problems of considerable
difficulty and of great practical utility, which have hitherto
to a considerable extent escaped notice, in consequence of
the science of Geometry having in modern times been
greatly neglected.

Many years ago it was our fate to make a voyage from
England towards the Southern Hemisphere ; it was part of
our duty to keep what are called ‘‘ watches” on board ship.
We had sometimes to remain on deck from 8 o’clock P.M.
till midnight, and at other times from 4 A.M. till 8 A.M., and
during these hours we had every opportunity of observing

VOL. IV. (N.S.) 20

286 The Pole Star and the Pointers. (July,

the changes in various celestial bodies, due to the half rota-
tion of the earth, which had occurred from 8 P.M. to 8 A.M.

The pole star and the pointers particularly attracted our
attention, for we could easily perceive how the pole star
appeared to sink nearer and nearer to the horizon as we
passed each day two or three degrees nearer the equator,
and we realised one of the first elementary laws of Astro-
nomy, viz., that the altitude of the pole above the northern
horizon was always equal to the latitude of the place from
which the pole was seen. In 52° N. latitude the altitude of
the pole was therefore 52°, whilst in N. latitude 40° the alti-
tude of the pole is only 40’, and so on.

Whilst observing the pole star and the pointers, at inter-
vals of about twelve hours, and when consequently the

pointers were at one time east of the pole star and at other —

times west of it, we noticed that at one time, and under one
condition, the pointers appeared to point more dire¢tly to-
wards the pole star than they did at other times. When
this peculiarity was at first noticed we believed it was in
consequence of our want of observation; for we naturally
argued that, as the fixed stars did not alter their relative
position as regards each other, it must follow that if the
pointers pointed towards the pole star at one time, they
must do so with equal exactitude at another time. To
imagine that the mere rotation of the earth on its axis
could cause any alteration in the relative position of three
stars in the heavens seemed almost an absurdity, and al-
though night after night, and morning after morning, we
observed that it really appeared as if the pointers did point
in a variable manner as regards the pole star, yet the fact
was passed over—as facts too often are—by those who
cannot account for them.

It was several years after our first notice of the pole star

and the pointers that our attention was again directed to
these celestial bodies, and we once more noticed the same
facts as those already referred to, and very shortly recog-
nised the law or cause which produced the appearance, and
found how more than one interesting problem depended
thereon.

In order that the whole of the problems resulting from
the above law should be thoroughly understood, the reader
ought to be acquainted with what we may term the geometry
of the sphere, and also the various terms used in Astronomy,
but to comprehend these problems will require but average
intelligence, a careful perusal of the following pages, and a

sufficient amount of imagination to picture, as it were, on —

1874.] The Pole Star and the Pointers. 287

the sphere of the heavens lines that of course cannot be
drawn there.

The first problem that we shall submit to the reader refers
to the apparent course of the sun in the heavens, from its
rising to its setting on the 21st of March.

We will suppose that a person is situated at a locality in
52 north latitude, and facing the south. At 6 o'clock in the
morning on the 21st of March the sun would rise above the
eastern point of the horizon, trace a curve or arch in the
heavens, until at the south it would attain an elevation above
the horizon of 38°. When exactly south the sun would
move nearly horizontally for a short part of its course; it
wouid then gradually descend, slowly at first, but more
rapidly afterwards, and at 6 o’clock p.M. would set below the
western point of the horizon.

If we could mark out on the heavens the course traced by
the sun, as stated above, we should draw a curve similar to
HS Rin the annexed diagram. In this diagram the horizon

Fig. 1.

H o R

is represented by the straight line HOR, H being the east,
0 the south, and Rr the west points on the horizon. s would
be the position of the sun relative to HOR when the sun
was south, and the arc OS, representing the sun’s altitude,
would be 38°.

It will be seen that, if we could sketch or mark on the
sky the course traced by the sun, this course would appear
to us a great arch, as shown by HSR.

Now this arch traced by the sun on the 2ist of March
is the position which the earth’s equator would occupy if
produced to the distant sky, and this arch is termed the
equinoctial. The equinoctial therefore cuts the east and
west points of the horizon, traces a curve in the heavens,
and at its south point is as many degrees above the horizon
as go exceeds the latitude of the place of observation.

We will now suppose that the observer turns round and
faces the north, and traces out on the sky the half of a great

288 The Pole Star and the Pointers. (July,

circle which cuts the east and west points of the horizon,
and passes through the pole of the heavens. This circle
the reader, on reflection, will perceive must be a circle at
right angles to the equino¢ctial, and its trace in the sky would
be as follows :—Starting from the east point of the horizon,
this circle would trace an arch in the heavens the highest
part of which would be at the pole, when its altitude above
the horizon would be equal in degrees and minutes to the —
latitude of the place of observation ; the curve would con-
tinue its arch-like form, and would cut the western point of
the horizon. This curve or arch traced in the sky by a
great circle passing through the pole, and cutting the east
and west parts of the horizon, vem appear as shown in the
following diagram.

In this diagram N represents the north portion of the
horizon, P ane pole of the heavens, E the east and wthe |
west points on the horizon, whilst the curve E P W shows

FIG. 2.
P

w

the curve or arch traced by a great circle in the sky, which
great circle is at right angles to the equino¢tial, and cuts the
east and west portions of the horizon.

The reader may perhaps wonder what these arches have
to do with the pole star and the pointers: they have every-
thing to do with them, and in fact are the key to this and to
other mysterious problems which seem to have hitherto
greatly perplexed some persons, for both this and the pre-
ceding arch are in reality straight lines, though they appear as
curves to us; for both this curve and the arch traced by the
equinoctial would appear like straight lines to a person at
the north pole of the earth, the equino¢tial there appearing
coincident with the horizon, and therefore like a straight
line, the curve E P W appearing like a vertical line and as
straight as a plumb-line.

We will now place relatively to the curved line WPE
three stars, and show what would be the relative changes

1874.] The Pole Star and the Pointers. 289

in twelve hours of these three stars, and due merely to the
rotation of the earth on its axis.

W N Erepresents, as before, the horizon; the curved line
PE a portion of the great circle, at right angles to the equi-
noctial, and cutting the east point on the horizon. P repre-
sents the pole of the heavens, and p w the remaining portion
of the great circle that is above the horizon.

Mivthe arc’ of the circle PE we represent: two stars;
aand gp. A straight line joining these two stars, and pro-
duced in the direction of the pole, would reach a point L.
We will suppose a star situated at L on the meridian, and
above the pole.

Under the conditions given above the stars 8 and a point
with great exactitude towards L, because an apparently
straight line joining 6 and a, and produced, would pass
through L.

FIG. 3.

w N E

In consequence of the rotation of the earth on its axis
the star at L and above the pole would in twelve hours be
carried round the true pole, P, and would trace a semicircle,
and reach the point L’ below the pole, the arc PL being equal
to PL’. Due to the same cause the stars a and 6 would
appear to trace semicircles round Pp, and would occupy, in
twelve hours from the time at which they were at a and £,
the positions shown by a’ and P’.

A line joining a’ and g’, and produced towards the pole,
would now reach the point L, as before, but the star which
was at L is now at L’, below the pole. Consequently the
two stars «’ and 6’ do not now point towards the same star
at which they pointed when they were in the positions shown
by « and p.

In order to illustrate the problem we have selected three
stars in such a relative position as to show the effects in a
prominent manner, and it happens that the actual position
of the pole star and the pointers is not so very different from
that of the three stars given above. We will now map out,

290 The Pole Star and the Pointers. (July,

as it were, the pole star and the pointers according to their
true position relative to one another, and as seen by an ob-
server in N. latitude 52°, at various times.

The pole star is not situated exactly at the pole of the
heavens, but is distant about 1° 27’ from the true pole, and
therefore describes every twenty-four hours a circle round
the pole, the radius of which circle is about 1° 27',—that is,
nearly three times the apparent angular diameter of the
sun, for the diameter of the sun subtends an angle of
about 32’.

The pointer nearest the pole is about 27° 34' from the pole,
whilst the second pointer is about 32° 49’ from the pole.
These two stars during every twenty-four hours appear
to trace circles in the heavens round the pole of the heavens,
the radius of each circle being 27° 34’ and 32° 49’.

We will next refer to the lateral divergence of these three
stars from what we may term a straight line, and in order
to do this we must refer to what is called ‘“‘ Right
Ascension ;”’ a term which probably some readers may not
be acquainted with, but we will give such a popular descrip-
tion thereof as shall render the explanation intelligible to any
person.

The right ascension of the pole star is about one hour
and twelve minutes, which converted into degrees is 18°.
The right ascension of the nearest of the pointers, viz.,
a Urse Majoris, is ten hours fifty-five minutes, whilst the
second pointer 8 Urse Majoris has a right ascension of
ten hours fifty-three minutes. Converting these differences
of right ascension into degrees it follows that the difference
in right ascension between the pole star and the pointers is,
in round numbers, 145° 43’.

Let us now explain this fact in more popular language.

If in the following diagram P represent the pole of the
heavens, Ss the position of the pole star distant 1° 27’ from
Pp, aand @ the two pointers, then the angle s P a will be
145° 43’

Fic. 4.
Ss

[pase ae PUY

Now the point p always remains fixed in the heavens, and
whilst s revolves round Pp, and a and £ also revolve round P,
yet the angle s pa will always remain a constant in value,
and will always be 145° 43’.

Wecan now trace out the changes which occur in the
apparent relative positions of the pointers and the pole star

1874.] The Pole Star and the Pointers. 291

under certain conditions, and ‘we will@first describe these
when the pointers are east of the pole star.

In the following diagram P represents the pole, s the pole
star,a and @ the pointers, H N E the horizon, E the east, N

FIG. 5.

H N E

the north, and H the west points. Under these conditions
the pointers point with tolerable exactitude towards the pole
star. When twelve hours have elapsed the pole star will be
seen at S’ in its circle, the stars a and 6 will appear in the
positions a’, 6’, and it is now evident that these two stars
do not point at the pole star, although as before the angle
Bera iS t45 43’.

In six hours after the stars a’ and #' were in the position
shown in the last diagram they would be on the meridian
and below the pole, and as these two stars differ only two
minutes in right ascension they would, when on the meridian
and below the pole, point almost vertically upwards. The
pole star, however, would now be go° in its circle from s'
in the last diagram, consequently the pole star and the
pointers would as regards each other then occupy the relative
positions shown in the following diagram, where H 0 R

Fic. 6.
“A

H co) R
represents the horizon, 0 the north point of the horizon,
P the pole of the heavens, s the pole star,a and P the
pointers. The angle s Pa being as before 145° 43’.

292 The Pole Star and the Pointers. (July,

It is evident that under the above conditions the pole star
is not pointed at directly by the pointers, nor will it be until ~
the stars a and 8 ascend to the east and reach nearly the
same altitude as the pole star.

It will be evident from the preceding demonstrations that
the pointers point with the least exactitude towards the pole
star when then they are west of that star and on the great
circle nearly at right angles to the meridian. It may
appear somewhat singular to many readers when we state
that this appearance (for it is but an appearance) will hold
good for our latitudes, but it would not occur to a person
who might be situated at the North Pole. Such a statement
may seem incorrect, but it is a truth, the reason for which ©
may be understood by the following description :—

To a person situated at the North Pole every star in the
heavens would appear to trace a circle during twenty-four
hours round a point exactly over his head. Every’star,
therefore, would appear to move parallel to the horizon. If
these four or five stars were arranged in a _ straight
line from the horizon up towards the zenith, these four or
five stars would always appear to an observer at the pole to
lie in the same straight line. The curve or arch joining
p and R in the last diagram would appear to an observer at
the pole a straight line rising from the horizon dire¢tly to the
point over his head, and not a curve or arch, as it appears
to a person in such a latitude as 52°.

Here, then, we have the key to the peculiar fact that the
pointers do not always appear to us to point with equal
accuracy towards the pole star. It is because owing to what
we may term the peculiar perspective of the sphere of the
heavens that which appears under one condition as a straight
line may appear under another condition as a curved line,
and as the pointers are on the apparent sphere of the
heavens, and alter their relative positions as regards the —
horizon, the effects are such as we have stated them to be.

In order to render this problem as intelligible as it should
be, we will again refer to the course or trace of the equino¢tial
on the sphere of the heavens, and described in an early page
of this article. We pointed out that the equinoétial, if it
could be marked out on the sphere of the heavens, would be
represented by a great arch which cut the east and west
points of the horizon, and attained an altitude at the south
equal to go° less the latitude of the place of observation.
This curve would remain constantly marked on the sky
during any number of rotations. It would be evident to our
senses that a line must be a curved line which could be

1874.] The Pole Star and the Pointers. 293

drawn on the sky commencing from the east part of the
horizon, rising rapidly at first as an arch does rise, then as
the equinoctial approached the south the arch would be
traced nearly horizontally, then it would slowly descend,
afterwards more rapidly, and finally cut the west point of
the horizon. Therefore every portion of this equinoctial
would appear a portion of a curve, and it could not be con-
sidered a straight line any more than a rainbow appears a
straight line.

What shall we say, however, when we trace out the
equinoctial on the sky as it would appear to a person at the
North Pole ?

To an observer at the North Pole the terms east and west
do not exist. The south is beneath his feet, the north
exactly over his head, and the east and west undefined. To
him the equinoctial would not rise above his horizon as it
would to an observer in middle latitudes, but the equino¢tial
would coincide with his horizon in all directions.

To every person who may be on the same level as the
sea, and when a clear defined sea outline is visible, the
horizon appears like a straight line, and all parts of the
horizon appear like portions of a straight line: therefore to
an observer at the Pole the equino¢tial will appear like a
straight line, and will be coincident with the horizon, yet to
an observer in middle latitudes the equinoctial will always
appear as an arch in the heavens.

' The same geometrical or optical laws which cause the
equino¢ctial to appear a straight or a curved line, according
as the observer is in one part or another part of the earth,
also cause the pointers to appear under certain conditions
to point exactly towards the pole star, whilst under other
conditions they will not appear to point with equal accuracy
to the same object.

The same laws produce other effeéts in connection with
certain celestial bodies, some of which effects are so palpable
as to attract the attention of every observer, whilst other
phenomena are noticed (spontaneously as we may term it)
only by those who possess good observational powers. When,
however, the peculiar facts are pointed out, and the celestial
objects themselves illustrate the problem, few persons are
incapable of perceiving the paradox, and the majority are
anxious to learn the causes which produced it.

In the present article we have confined our description to
the pole star and the pointers, but on a future occasion we
purpose treating two other phenomena even more easily
observed than is the fact connected with the pointers; yet

VOL. IV. (N.S.) 2P

294 Peat Bogs. (July,

these others have long remained mysteries to certain in-
dividuals.

The reader who has read and mastered the preceding
problem may amuse himself by testing the observational
power of his friends. He may enquire whether his friend
has ever remarked the pole star and the pointers. Then he
should carefully word his next question somewhat in the
following terms :—‘‘ Of course the pointers always point
with equal accuracy towards the pole star,’ and in the
majority of cases he will obtain for his answer, “‘ Of course
they must do so, as the stars never alter their relative
positions from each other.” If the reader, instead of the
above careful question, were to say, ‘‘ Have you ever 're-
marked that the pointers do not always point with equal
accuracy to the pole star,’ he would in many cases receive
some such answer as the following :—‘‘ Well, I fancy I have
noticed it, but I am not very sure about it.” :

So rarely do we find any but the most candid and pro-
gressive, who are willing to acknowledge their ignorance of
a subject, that the above problem may afford those who have
thoroughly mastered it considerable amusement and some
information when they cross-examine those among their
acquaintances who profess to have a knowledge of astronomy.

Ms PEAT) bOGs;
By G. H. Kinawan, M.R.I1.A., &c.

HE formation or growth of peat bogs and that of most,
at least, of our principal coal seams, were evidently
very similar: it is therefore interesting to be ac-

quainted with what may be ascertained about the former.
Why peat bogs began to grow at first is a question often
asked, but as yet not satisfactorily answered. In Great
Britain and Ireland there are three classes of peat, distin-
guished by three modes of occurrence, namely, first, the
preglacial or intraglacial peat; second, submarine peat; and
third, the subaérial, or the peat accumulations that are
still being formed. The latter, however, as will hereafter be
mentioned, can in certain places be subdivided, as there is
proof of a long cessation of peat growth having intervened
over vast areas during its period of formation. In this paper

1874.] Peat Bogs. 295

the facts witnessed in Ireland will be those chiefly consi-
dered, but at the same time some reference will be made to
places in Scotland or England as they show the similarity
of the growth of peat in the three countries.

There does not appear to be in Ireland any peat accumu-
lations under the undoubted normal boulder-clay-drift.
Near Nenagh, Co. Tipperary, there is a black peaty bed
under ‘‘forty-three feet of hard calcareous clay, with
numerous lumps of limestone intermixed, but unstratified.”*
In Boleyneendorrish Valley, near Gort, Co. Galway,
there is an argillous peat under about 25 feet of a glacial
drift,t and in some of the pits of the Newtown Colliery,
Queen’s Co., 3 feet of peat was found under 96 feet of drift
which was, at least in part, glaciai. From this it will be
seen that although such peaty accumulations may not have
been formed prior to the glacial period, yet that some are
evidently intraglacial,—that is, they were formed subsequent
to the beginning and prior to the end of the glacial period.
There are also fragments of peat found in the marine
gravels in the country west of the south portion of Lough
Corrib, Co. Galway. These gravels, when compared with
the gravels of the “‘ Esker Sea period” of the central plain
of Ireland, seem to be evidently recent ; still they appear to
have been formed before the final disappearance of the ice
from the neighbouring highlands, as ice-carried erratics are
occasionally found lying upon them. In the peaty accumu-
lations of Boleyneendorrish, Dr. Melville, of the Queen’s
University and Queen’s College, Galway, detected numerous
cones of the Pinus sylvestris, cones of the A bies excelsa, DeC.,
fragments of wood (chiefly coniferous), portions of branches,
scales of bark, pieces of fir bark, an imperfect hazel nut,
and leaves of plants, which prove the presence of such
trees on the western portion of the British Islands during at
least the latter portion of glacial times.

Submarine peat is not uncommon off the coast of Ireland,
and in many of the estuaries and brackish water lagoons.
In the east of Ireland, at the present time, there is very
little peat growing on the lowlands, yet off the coast, and in
the estuaries, &c., submerged bogs are not uncommon.
They have been proved to occur from high-water mark to a
depth of 20 or 30 feet; those under the estuary muds of
Wexford Harbour having been found to a depth of 20 feet
below the surface of the mud, or about 23 or 24 feet below

* Paper by T. OLpHAM, M.R.I.A., Journ. Geol. Soc. Dubl., vol. iii., p. 64.
+t Mem. Geol. Survey, ex Sheets 115 and 116, p. 28.

296 Peat Bogs. (July,

mean high-water mark: these bogs are found to contain the
roots and trunks of oak, yew, deal, hazel, sallow, and a
timber like ash, also hazel nuts. In the south and west of
Ireland lowland bogs are numerous, and it is a common oc-
currence to find—off a coast where bogs now form the sea
margin—peat from 8 to 12 feet deep, even at low water of
spring tides, giving a depth below mean high-water mark of
from 23 to 25 feet. In these bogs the roots and trunks of
oak, yew, deal, willow, and hazel are found, similar to the
tree remains that occur in the inland bogs. Off the south-
east coast of England there are also submarine bogs; those
in Romney Marsh and Pevensey Level being at nearly simi-
lar depths below the mean high-water mark. It has been
suggested that the peat accumulations found in lagoons,
estuaries, and even on the open coast, may have grown at
their present levels, the sea being kept out from them by a
barrier of sand, gravel, or the like, which was subsequently
swept away or moved inland. If, however, we consider a
moment, the erroneousness of such an idea is apparent.
Take, for instance, such places as Romney Marsh in Eng-
land, or Wexford Estuary in Ireland, where we find the
roots of oak 1 situ more than 15 feet below the mean low-
water mark. These trees, at the time they were growing,
would have been liable at any time to have been inundated,
while even at low water of spring tides they would have had
no drainage. Such trees as the willow and alder might pos-
sibly grow under these conditions; but such trees as the
oak, yew, fir, ash, and hazel require a drainage from the
ground on which they grow; these, then, never could grow
and arrive at maturity on ground below low-water mark.
Such bogs, therefore, as those in which the remains of the
last-mentioned trees are found, must have been while the —
trees were growing above high-water mark. Moreover, the
process of subsidence would seem to have been gradual, to
allow the peat-forming plants time to grow and decay in oft-
repeated succession.

The plant-remains in the submarine peat are, as a general
rule, similar to those found in the subaérial lowland or ‘‘ red
bogs,” and we may reasonably conclude that the peat accu-
mulated under very similar conditions,—that is, as a “red
bog,” and not in a lagoon or marsh. It also must have
taken a very long time to accumulate, as peat when drained
will contract more than half its height, while if weighted
and compressed—as the peat under estuary mud—it would
be reduced a third or fourth more, so that the 5 feet of peat
under the muds of Wexford Estuary would represent a
growing bog of from 15 to 20 feet in depth.

1874.] Peat Bogs. 297

The normal lowland or ‘‘red bogs” of the central plain
of Ireland are very similarly circumstanced to the ordinary
coal seams, having an under-clay which is more or less pene-
trated by the roots of the trees and larger plants which at
the first occupied the land. In most of them, as also in
many other low-lying bogs, the roots and the trunks of the
trees under the peat, or in the lowest strata, are principally
those of oak and yew, as if prior to the growth of the peat
the low country was for the most part a vast forest of these
kinds of trees, the oak greatly preponderating. In these
forests mosses and other peat-producing plants began to
grow and flourish, till eventually they stopped the drainage,
and formed an envelope of peat which gradually killed the
trees, while subsequently the stems rotted off, between wind
and water, the trunks toppling over and being entombed by
the succeeding growth of the peat. After the disappearance
of the major portion of the oak forest, the bogs for years
gradually increased in depth, till suddenly—from some as
yet unexplained cause—their growth ceased, and on their
surfaces forests of deal sprang up. During all this time,
however, portions of the original oak forest were preserved,
and some of them apparently remain in certain places to
the present day. This seems to have been due to the oaks
and associated trees being destroyed only in those compara-
tively level places in which the peat could easily accumulate.
On hills that were above the general level of the peat the
oak would still flourish, and during the ‘‘ Deal Forest Age”
each of these hillocks remained an oak grove. At the pre-
sent day, in many parts of Ireland, the hills and exposures
of drift in a flat bog are called “‘derries” (Anglice, oak-woods),
the ancient name, which has survived down to the present
age from the time when they were oak groves surrounded by
forests of deal. Still this name may be more modern, as it
is probable that, even after the deal forests disappeared,
many of these hills still remained oak-woods. ‘The derries
in the midland counties of Ireland have long since been
cleared of their timber, and are now under tillage or grass
land, but in a few places—such as some of the wild tracts
in Mayo—the oak may still be found growing on the drift
islands in the bogs, it always being associated with yew,
hazel, birch, ash, and holly; probably the last three trees
were also denizens of the primary forests, but their timber
has long since disappeared, they being of kinds that rot
quickly in bog.

That such was the mode of the growth of the bogs is
proved by the different sections exposed, as beneath the peat

298 Peat Bogs. (July,

in the clay, marl, or gravel, are found the “corkers,” or
roots of the oak and yew, following the undulations of the
ground, while above them—in horizontal layers, and sepa-
rated from them by from about 4 to 10 or 12 feet of peat—
are the roots of the deal forest, which at the sides of the
hills join the oak roots, as shown in the accompanying
sketch section. In a few lowland bogs, however, and in
many bogs in the mountainous districts, the lower and upper
systems of corkers will belong to deal trees, as if in such
places there had been two distinct ages of deal forests.
Some of the lowland or red bogs are of great depth, ina
few places up even to 50 feet, but on an average they gene-
rally do not exceed 20 or 30 feet, and often are much less.
A typical red bog gives four kinds of peat: near the surface
is a clearing of more or less living organic matter, from 3 to
6 feet in thickness ; under this is white turf, then brown turf,
and lowest of all black or stone turf. White turf is a nearly
pure organic substance, very light when dried, burns quickly,
giving out only a little heat, and leaves little or no ash.

Fic. 7.
al eS
b * é
Pca. tea cen ae Waa Fes Ayn

A
Mas PAT ae mp ask ahh

a. Drift Hills or Derries. 0. Surface of bog. c. Dealcorkers. d. Oak corkers on gravel.
Brown turf is always more or less mineralised. Black or
stone turf is a chemico-organic production, and may contain
such minerals as pyrite or marcasite; often it is semi-
crystalline and seems to pass into lzgnyte, and when burnt it
always leaves more or less ash. A variety in many bogs is
locally called ‘“‘ Monagay”’ turf, which is very brittle, and
full of the fragments and stems of flagger-like plants.
Under monagay turf marl always is found, while under
typical black turf there is usually gravel, suggesting that
the monagay turf accumulated in a marsh. Another variety,
always found at the very bottom of a bog when cut, is of a
pale greenish-yellow colour: this, if allowed to dry, fully
“melts” or disintegrates under the atmosphere, but if
stacked when half dry it becomes a beautiful, hard, compact
turf, that burns with a strong heat and brilliant light.

The residue or ash of peat generally, but not always, is
greater the more deeply the peat is seated. In some places
mineral matter may be carried up into the peat from springs
and the like; but the ash of peat seems usually due to the

1874. | Peat Bogs. 299

plants growing on the surface collecting their inorganic food
from the atmosphere, and after their decay to the collected
mineral substances being continually carried downwards by
the water percolating through the mass: in this way each
lower portion becomes more impregnated than the parts
above it, and when burnt its ash or residue is greater.

The bogs on mountains are vastly different from those on
the low lands. The latter usually grow on more or less Hat
places, where the substratum is non-porous, on which they
form extensive level plains, while in the mountainous districts
bog may grow anywhere on the hill-tops, as well as in the
valleys, and from the latter they creep up the slopes over
porous and non-porous strata. They are generally of small
depth as compared with the lowland bogs, as here the peat
grows much more slowly and more densely. In typical
mountain bogs the clearing, or partly living organic matter,
rarely exceeds 12 inches in depth, and this les on brown
turf, under which there may be black turf, but not always, as
in some places the peat envelope is too thin to form the
latter by compression. The difference between mountain
and lowland peat is evidently due to the different rate of
growth of the peat-producing plants in the respective posi-
tions. In the low flat land the growth of the plants is more
rapid than among or on the mountains; consequently while
on the former a light spongy substance is accumulating, on
the latter a heavy felt-like mass is being formed. Besides,
in all mountainous distri¢ts portions of the peat are very
much subject to denudation by rain, runlets, and wind,
which carry particles of peat from one place to another, and,
by depositing them on the surface of the growing peat, keep
the surface even, and make the peat compact and firm. In
this way, on the growing peat may be deposited a layer of
derivate or sedimentary peat, which will afterwards become
interstratified by a subsequent growth of the plants. In flat
mountain bogs, and also in the lowland bogs, when the latter
are situated at the base of a hill or along a river subject at
times to extensive floods, layers of sand, gravel, silt, or the
like, may be found in the peat, such foreign material having
been deposited on the surface of the bog during freshets,
while afterwards the peat grows over them.

In coal-mining we find parts of seams absent; such defi-
ciencies are called “ faults,” ‘‘ troubles,” ‘‘ horses,” &c., by
the colliers, and the formations of these coal-less portions
of a vein are explained by the study of some peat bogs; as
we find the mass of the peat in some places denuded by the
wind, and in others by a stream, which cut into it and break

300 Peat Bogs. (July,

its continuity, and if, after this, the bog were to be covered
up by newer strata, such vacancies would be filled with
foreign materials similar to the “‘ troubles” or ‘‘ horses” in
a coal seam.

In the mountain bogs of the British islands the prevailing
timber seems to be deal, and some of the sticks are of lengths
that the fir rarely attains at the present day in these
countries. The absence of the remains of the oak in the
highlands of these islands would seem to suggest that the
oak could not flourish above a certain altitude, which in
Ireland seems to have been about the 400 feet contour line.
This would seem to suggest that prior to the age of the first
growth of the subaérial peat the lowlands, and the hill-sides
to a certain height, were covered with oak forest, while
above that height, the hills grew deal, the deal trees then
flourishing at much greater altitudes than now, as large
sticks are sometimes found in bogs at heights of above 1000
and 1200 feet.

From the above we may regard it as probable that there
has been, since the glacial period at least, two ages of the
most active growth of peat—irst, after the great oak forest
period, and second, subsequent to the deal forest period.
‘That a considerable break occurred between them is evident,
but the cause of itis unknown. ‘There may indeed have been
a third period, while the now submarine bogs were growing:
this, however, does not appear probable, for at the present
day the lowland bogs may grow at any height from high-
water mark to the 200 or 250 contour line: it is therefore
possible that the submarine bogs were forming at the same
time as the lower strata of our present subaérial bogs, al-
though now found under such different conditions. The
turf-cutters on the sea shore generally tell you that “the
turf is of the same depth at high- and low-water mark,”
but they cannot say if the corkers or roots of the trees stand
perpendicular. If they are correct it would necessitate that
seaward the peat has sunk more than at the shore-line.
On a straight shore-line this might be possible, but on the
indented coasts of our bays it is highly improbable.*

In studying bogs, one of the greatest difficulties is to pro-
cure reliable data by which to be enabled to estimate the
rate at which they grow. Undrained bogs grow; drained

* Near the shore-line I have seen the corkers standing perpendicular, but I
never saw an off-shore hole bottomed, as the incoming tide usually drives
away the turf-cutters before they can take out all the turf; and I very much
suspect my informants told me what they considered most probable, and not
what they actually saw.

1874.] Peat Bogs. 301

bogs, as long as the drains are effective, will not; and it
would appear, from the Irish annals, that both before and
since the English occupation attempts were made to drain
and reclaim the lowland bogs, while they were again allowed
to run wild in subsequent troublous times. ‘These artifi-
cial stoppages of the growth of the peat have complicated
matters, as respects some bogs, so that it is now impossible
even to guess how long they may have been growing. At
the present day the growth of the lowland bogs in Ireland
is generally small, on account of their being more or less
‘drained, and from turf being cut round their margins. In
places, however, where the drainage has been for a long
time neglected, a perceptible change in their height will take
place: this, however, may in part be due to the bog soaking
and swelling with water. A road through a bog will rise if
the side drains are allowed to become choked. The margins
of others, after the turf-cutting has been abandoned, gra-
dually begin to resume their natural form, and if left long
enough the peat will begin to creep out upon the adjoining
upland, the growth being sometimes very rapid: certain
bog-holes that were abandoned in 1848 are now nearly filled
with new peat, but of a very soft spongy nature.

In the mountainous districts Nature has been less inter-
fered with, and thus many facts in relation to the growth of
bogs can be advantageously studied. Bogs naturally grow
more readily on flats than elsewhere, and among the hills
we find the deepest peat on the flat hill-tops and in the flat
valleys: it, however, does not confine itself to such places,
but creeps up and down the adjoining slopes. The latter
process might be expected to be the easiest: this, however,
does not appear to be the case, especially if the slope is
steep. Bogs on an exposed hill are denuded at the edge
during storms, especially if these are accompanied by rain.
Such bogs are thus prevented from creeping downward,
while the annual growth and decay of the plants increase
their thickness, thus forming low long cliffs in all exposed
places ; it is only in sufficiently sheltered situations that the
peat covering extends continuously downwards. But bogs
creep rapidly upward, even in places where the slopes are
composed of porous materials ; as the wind, rain, and runlets
will add boggy stuff to its edge, forming rapidly a-soil in
Which heather, moss, and other peat-producing plants ra-
pidly grow. In some of the valleys in the Connemara hills
there are coarse shingle slopes, with a covering of peat often
as much as 8 feet deep, while the bog on the adjoining flats
is not much deeper. This peat originated with peaty matter

VOR. 1V. (N.S.) 2Q

302 Peat Bogs. July,

from the flat tops of the hills, that was lodged on the surface
of the stones, by rain and wind, on which heather, &c.,
grew, and by the growth and decay of such the great thick-
ness of peat was accumulated; from these shingles the peat
is extending up the slopes of the hills.

In some of the once-inhabited but now depopulated valleys
(and similar facts may be observed in parts of the highlands
of Scotland) the growth of the peat is remarkable; it now
having nearly obliterated the sites of the farmsteads and
fields. The growth of peat differs on the hill-tops and in
the valleys: on the first it is somewhat similar to that of
lowland bog, in the plain it being principally due to the
growth and decay of vegetation; for this reason it is more
or less tussocky: but the turf in the valleys is only partially
due to vegetable growth and decay, for it is partly derived
from peaty matter carried on to it; it is therefore usually
much more dense and level on the surface; it is, however,
very variable in composition, as in some places it is more
favourably situated than in others for receiving extraneous ©
matter.

As yet no human relic has been recorded from the sub-
marine bogs; but as such peat accumulations have only been
proved by borings or small excavations, while vast extents
are unexplored, it is not likely that they should have been
found; but in the subaérial peats they are not uncommon.
In Drumkelin bog, parish of Inver, Co. Donegal, a log house
was found under 14 feet of bog, the house being 8 feet high,
while under it was 15 feet of bog, in all 37 feet deep. Stone
celts, sharpened stakes, and methers full of lard or butter,
have at different times been exhumed from under bog from
10 to 15 feet deep, in the mountain pass N.W. of Glenbon-
niv, parish of Feakle, Co. Clare; and the late J. Beete Jukes,
F.R.S., on seeing the huts, remarked that they were exactly
similar to the huts built by the natives of Newfoundland to
shelter them while waiting for the deer in their annual
migration. In one place in the ridge of hills N.W. of the
small market-town of Clifden, Co. Galway, wattle fences
were found stuck in the clay under bog from 8 to 12 feet deep.
The ridge of these hills is very uneven, large flat spaces oc-
curring, usually connected by more or less narrow passes.
These wattle fences consisted of stakes driven into the
ground, and interwoven with horizontal rods or branches,
gaps here and there being left open; they always occurred
opposite to one of the passes leading from one flat to
another ; and what seems remarkable about them is that they
are similar to the description of traps made for deer at the

1874.] Peat Bogs. 303

present day in Russia. In the bog close to Castleconnell,
Co. Limerick, a mether full of a substance like whey was
found standing by an oak corker, and 5 feet above the oak
corker was a layer of deal corkers, while a short distance
above the horizon of the latter, extending from the edge of
the bog next the old castle of the O’Connings to an esker
called Goig, was a roadway of oak timber built similarly to
an American corderoy, and over the roadway was from 10 to
12 feet of solid peat; alongside the road are said to have
been the remains of ancient bog-holes in which the peat was
cut in a mode similar to that of the present day. From this
bog we learn that the oak forests were inhabited, while sub-
sequently oak timber was accessible in the neighbourhood,
probably on Goig, after the destruction—at least in part—of
the great pine forests, and that peat fuel was used at a very
eatly age. The finds of stone and other weapons, also of
butter or lard, are too numerous to mention, the latter oc-
curring sometimes in lumps without the trace of any enve-
lope,—sometimes in methers, barrels, cloths, and in conical
vessels made of hoops and straight sticks, lined with cloth ;
some of them evidently were purposely buried, while others
seem to have been dropped, and subsequently covered by
the growth of the peat.

Hitherto we have been occupied with facts; now, how-
ever, we will, in part, have to deal with conjectures. The
intraglacial peats in the localities that have been enumerated
seem to be very ancient ; those at Newtown, Queen’s Co.,
and near Nenagh, Co. Tipperary, undoubtedly are so, and
after their accumulation must for years have been under an
ice-sheet. The peaty stuff in the Boleyneendorrish Valley,
Co. Galway, must also have been under ice, but probably at
a much later age than the others, and possibly after the ice
had left most of the low country, while the pieces of peat in
the marine gravels west of Lough Corrib are—comparatively
speaking—recent, as the gravels were formed subsequent to
the Esker Sea period, and during the time when only the
Jands under the present 150 feet contour-line were sub-
merged. In acoom that hes on the north side of Mount
Leinster, Co. Carlow, there is a peat under drift from a few
inches to over 4 feet in depth: this peat, however, has not
been previously mentioned, as the drift evidently is not a
normal glacial drift, but has been arranged by meteoric
action, and was probably washed down from a higher part of
the coom.

Since the oak forest age there must have been various
changes in the climate of Ireland. Oaks, indeed, would

304 Peat Bogs. (July,

grow at the same altitudes as those at which the corkers are
found in the bogs, but then it must be remembered that
these places are probably at least 50 feet lower than they
were when the oaks flourished ; besides, the bog oak occurs
in exposed situations in the west of the island, where now
no trees of the same dimensions would grow; and deal at
the present day cannot be grown at the altitudes or in the
situations where large bog deal sticks are found.

The history of the submarine and estuary peats may be as
follows:—When the land was about 4o or 50 feet higher
than at present, or even more, forests grew; subsequently
the drainage became defe¢tive, either from the land sinking
or from the growth of ferns, mosses, and the like,—probably
the latter,—till eventually the forests disappeared, and bogs
replaced them. Afterwards the land must have been de-
pressed, and probably in general rapidly, for if the sinking
was gradual the upper strata of the bogs would have been
formed from the growth and decay of flaggers, reeds, and
other marsh plants, while usually the peat seems to have
formed from the same class of vegetation as that which is
now forming the upland bogs.

In the subaérial bogs the decay of the oak forest would be
somewhat similar to the decay of the woods at the com-
mencement of the submarine peats, as the growth and decay
of ferns, mosses, and other denizens of a forest, would gra-
dually stop the drainage, and produce bogs in all low-lying
places; these eventually would extend their limits, until all
the woods on the low lands were destroyed and covered by
peat; but the stoppage of the growth of the bogs and the
advent of the deal forest is more difficult to explain.

Deal trees could not be introduced or flourish on a bog
until it was first drained and dried, and how this was accom-
plished can only be conjectured. It seems impossible that
the drainage of the bogs could be due to artificial means, for
although we know portions were reclaimed at different times,
yet such reclamation could not have been universal, and in
all parts of Ireland the pine forests seem to have existed at
the same time; we are therefore forced to believe that they
were introduced by natural causes. At the present day we
have about five wet years, five of average character, five fine
years, five of average character, and so on, in recurrent
cycles; but a similar climate would not have furnished fa-
vourable conditions for the growth of the pine forests. We
must therefore suppose that there was a long period of
drought inauspicious to the growth of peat-producing plants,
during which the bogs became drained, dried, and consoli-

1874. | Peat Bogs. 305

dated ; subsequently the fir trees grew upon them, and came
to maturity. After the growth of the forests the trees would
attract the rain, and the climate would again become moist,
when peat-producing plants would flourish, till eventually
the pines were also destroyed and replaced by bogs. Against
such a theory it must be allowed that, after the forests were
destroyed, the climate ought to have again become dry, yet
there does not appear to have been any material change
during the last two hundred years, since the destruction of
the great upland forests in Ireland recorded in the annals.

In conclusion, we may attempt to make a rough estimate
of the years that have passed since the beginning of the
growth of the oak forest. Some of the largest oaks in the
bogs have been calculated, by their rings, to be more than
two hundred years old, while fir trees, by similar indications,
are found to be over one hundred years old. Many bogs are
a more or less felt-like mass, but in others each year’s growth
is represented by a layer or lamina, and these lamine in the
brown turf are usually from fifteen to twenty in number per
inch, or about two hundred in a foot, while in the black turf
the average is about four hundred in a foot. From these
data the age of the oaks under the previously mentioned
Castleconnell bog may be as follows :—

Mak forest age . . yl 4 about, 300 yearse
Five feet black turf, at 400 years ATOOt Lalit. 2OOOU ,s
‘Time allowed for the change of climate, say 100 ,,
Meal torest age .. .° . Shela about BOO a5
‘Twelve feet mown turf, Ai 200 years afoot . 2400 ,,

5000

Such an éstimate is evidently very low, as it ignores the
white turf or clearing,—also the different artificial stoppages
of the growth of the peat, one considerable stoppage, at least,
being during the time the road to Goig was being made and
used: we, however, learn that in this part of Ireland at
least five thousand years must have elapsed since the oak
first began to grow.

( 306 ) (July,

Ill.. THE PAST. HISTORY OF OUR ,MOOM
By Ricuarp A. ProcrTor, B.A. (Camb.),
Author’ of **The Sun,” “The. Moon,; sree

\Jo HE appearance of two treatises upon the moon, both
) of them considerable in dimensions, and within six
months of each other, indicates the renewed interest
which astronomers are taking in the study of the nearest of all
the celestial bodies. It is noteworty, also, that in both these
treatises,—in that by Nasmyth and Carpenter as well as in
my own work,—the moon is regarded, not as a mere satellite
of the earth, but asa planet, the least member of that family
of five bodies circling within the asteroidal zone, to which
astronomers have given the name of the terrestrial planets.
There can be no question that this is the true position of
the moon in the solar system. In fact, the fashion of re-
garding her as a mere attendant of our earth may be looked
upon as the last relic of the old astronomy in which our
earth figured as the fixed centre of the universe, and the
body for whose sake all the celestial orbs were fashioned.
In this aspect, also, the moon is a far more interesting object
of research than when viewed as belonging to another and
an inferior order. We are able to recognise in her ap-
pearances probably resulting from the relative smallness of
her dimensions, and hence to derive probable information as
to the condition of other orbs in the solar system which fall
below the earth in point of size. Precisely as the study of
the giant planets, Jupiter and Saturn, has led astronomers
to infer that certain peculiarities must result from vastness
of dimensions, so the study of the dwarf planets, Mars, our
moon, and Mercury, may indicate the relations we are to
associate with inferiority of size.

This thought immediately introduces us to another con-
ception which causes us to regard with even greater interest
the evidence afforded by the moon’s present condition. It
can scarcely be questioned that the size of any member of
the solar system, or rather the quantity of matter in its
orb, assigns, so to speak, the duration of that orb’s existence,
or rather of the various stages of that existence. ‘The smaller
body must cool more rapidly than the larger, and hence the
various periods during which the former is fit for this or that
purpose of planetary life (I speak with purposed vagueness
here) are shorter than the corresponding periods in the
life of the latter. ‘Thus the sun, viewed in this way, is

1874. | The Past History of our Moon. 307

the youngest member of the solar system, while the tiniest
members of the asteroid family, if not the oldest in reality,
are the oldest to which the telescope has introduced us.
Jupiter and Saturn come next to the sun in youth ; they are
still passing through the earliest stages of planetary ex-
istence, even if we ought not rather to adopt that theory
of their condition which regards them as subordinate suns,
helping the central sun to support life on the satellites which
circle around them. Uranus and Neptune are in a later
stage, and perchance when telescopes have been constructed
large enough to study these planets with advantage, we may
learn something of that stage, interesting as being inter-
mediate to the stages through which our earth and Venus
on the one hand, and the giant brothers Jupiter and Saturn
on the other, are at present passing. Atter our earth and
Venus, which are probably at about the same stage of
planetary development (though owing to the difference in
their position they may not be equally adapted for the
support of life) we come to Mars and Mercury, both of which
must be regarded as in all probality much more advanced
* and in a sense more aged than the earth on which we live.
In a similar sense,—even as an ephemeron is more aged
after a few hours of existence than a man after as many
years,—the small planet which we call “‘ our moon” may be
described as in the very decrepitude of planetary existence,
nay (some prefer to think), as even absolutely dead, though its
lifeless body still continues to advance upon its accustomed
orbit, and to obey the law of universal attraction.
Considerations such as these give singular interest to the
discussion of the past history of our moon, though they add to
the difficulty of interpreting the problems she presents to us.
For we have manifestly to differentiate between the effects due
to the moon’s relative smaliness on the one hand, and those
due to her great age on the other. If we could believe the
moon to be an orb which simply represents the condition to
which our earth will one day attain, we could study her
peculiarities of appearance with some hope of understanding
how they had been brought about, as well as of learning from
such study the future history of ourown earth. But clearly
the moon has had another history than our earth. Her
relative smallness has led to relations such as the earth
never has presented and never will present. If our earth is,
as astronomers and physicists believe, to grow dead and cold,
all life perishing trom her surface, it is tolerably clear
from what we already know of her history that the ap-
‘pearance she will present in her decrepitude will be utterly

308 The Past History of our Moon. (July,

unlike that presented by the moon. Grant that after the
lapse of enormous time-intervals the oceans now existing on
the earth will be withdrawn beneath her solid crust, and
even (which seems incredible) that at a more distant future
the atmosphere now surrounding her will have become
greatly reduced in quantity either by similar withdrawal or in
any other manner, yet the surface of the earth would present
few features of resemblance to that of the moon. Viewed
from the distance at which we view the moon there would
be few crateriform mountains indeed compared with those
on the moon; those visible would be small by comparison
with lunar craters even of medium dimensions; and the
radiated regions seen on the moon’s surface would have no
discernible counterpart on the surface of the earth. The
only features of resemblance, under the imagined conditions,
would be probably the partially flat sea bottoms (though
these would bear a different proportion to the more elevated
regions) and the mountain ranges, the only terrestrial
features of volcanic disturbance which would be relatively
more important than their lunar counterparts.

I do not purpose, however, to discuss the probable future
of the earth, having only indicated the differences just
touched upon, in order to remind the reader at the outset
that we have not in ‘“‘the moon”’ a representation of the earth
at any stage of her history. Other and different relations
are presented for our consideration, although it may well be
that by carefully discussing them we may learn somewhat
respecting our earth, as also respecting the past history and
future development of the solar system.

I have already, on two occasions, discussed in these pages
some of the problems presented by the observed condition
of the moon’s surface, and in my treatise on the moon, I
have in several places indicated the views towards which
my study of the subject tended. But I have not attempted
to present any general theory on the subject, feeling, indeed,
that it was one which presented too many difficulties to be
hastily dealt with. It seems to me, however, that the enun-
ciation by Messrs. Nasmyth and Carpenter, of somewhat
definite theories respecting the moon’s surface, affords me a
favourable opportunity for advancing considerations which
I have had much in my thoughts during the last five or six
months, and which appear to me to accord more satisfactorily
with observed lunar appearances on the one hand as well as
with known terrestrial and probable cosmical relations on
the other, than the theories advanced in the treatise above
referred to.

1874.] The Past History of our Moon. 309

It appears reasonable to regard the moon, after her first
formation as a distin¢t orb, as presenting the same general
characteristics that we ascribe to our earth in its primary
stage asa planet. In one respect the moon, even at that
early stage, may have differed from the earth. I refer to its
rotation, the correspondence between which and its revolution
may probably have existed from the moon’s first formation.
But this would not materially have affected the relations
with which we have to deal at present. We may apply,
then, to the moon the arguments which have been applied
to the discussion of the first stages of our earth’s history.

Adopting this view, we see that at the first stage of its
existence as an independent planet, the moon must have
been an intensely heated gaseous globe, glowing with in-
herent light, and undergoing a process of condensation,
“‘soing on at first at the surface only, until by cooling it
must have reached the point where the gaseous centre was
exchanged for one of combined and liquefied matter.” To
apply now to the moon at this stage the description which
Dr. Sterry Hunt gives of the earth :—‘‘ Here commences
the chemistry of the moon. So long as the gaseous con-
dition of the moon lasted, we may suppose the whole mass
to have been homogeneous; but when the temperature
became so reduced that the existence of chemical com-
pounds at the centre became possible, those which were
most stable at the elevated temperature then prevailing,
would be first formed. ‘Thus, forexample, while compounds
of oxygen with mercury, or even with hydrogen, could not
exist, oxides of silicon, aluminium, calcium, magnesium,
and iron, might be formed and condensed in a liquid form
at the centre of the globe. By progressive cooling still
other elements would be removed from the gaseous mass,
which would form the atmosphere of the non-gaseous
nucleus.” ‘‘The processes of condensation and cooling
having gone on until those elements which are not volatile
in the heat of our ordinary furnaces were condensed into a
liquid form, we may here inquire what would be the result
on the mass of a further reduction of temperature. It is
generally assumed that in the cooling of a liquid globe of
mineral matter congelation would commence at the surface,
asin the case of water; but water offers an exception to
most other liquids, inasmuch as it is denser in the liquid
than in the solid form. Hence, ice floats on water, and
freezing water becomes covered with a layer of ice which
protects the liquid below. Some metals and alloys resemble
water in this respect. With regard to most other earthy

VOL. IV. (N.S.) aR

310 The Past History of our Moon. [July,

substances, and notably the various minerals and earthy
compounds like those which may be supposed to have made
up the mass of the molten globe, the case is entirely different.
The numerous and detailed experiments of Charles Deville
and those of Delesse, besides the earlier ones of Bischof,
unite in showing that the density of fused rocks is much less
than that of the crystalline products resulting from their
slow cooling, these being, according to Deville, from one-
seventh to one-sixteenth heavier than the fused mass, so
that if formed at the surface they would, in obedience to the
laws of gravity, tend to sink as soon as formed.”

Here it has to be noted that possibly there existed a period
(for our earth as well as for the moon) during which, not-
withstanding the relations indicated by Dr. Hunt, the ex-
terior portions of the moon were solid, while the interior
remained liquid. A state of things corresponding to what
we recognise as possible in the sun may have existed. For
although undoubtedly any liquid matter forming in the sun
sinks in obedience to the laws of gravity towards the centre,
yet the greater heat which it encounters as it sinks must
vapourise it, notwithstanding increasing pressure, so that it
can only remain liquid near the region where rapid radiation
allows of sufficient cooling to produce liquefaction. And in
the same way we may conceive that the solidification taking
place at any portion of the surface of the moon’s or the
earth’s liquid globe, owing to rapid radiation of heat thence,
although it might be followed immediately by the sinking
of the solidified matter, would yet result in the continuance
(rather than the existence) of a partially solid crust. For
the sinking solid matter, though subjected to an increase of
pressure (which, in the case of matter expanding on lique-
faction, would favour solidification) would nevertheless,
owing to the great increase of heat, become liquefied, and
expanding would no longer be so much denser* than the
liquid through which it was sinking as to continue to sink
rapidly.

Nevertheless, it is clear that after a time the heat of the
interior parts of the liquid mass would no longer suffice to
liquefy the solid matter descending from the surface, and
then would commence the process of aggregation at the
centre described by Dr. Hunt. The matter forming the
solid centre of the earth consists probably of metallic and
metalloidal compounds of elements denser than those forming

* It would still be somewhat denser, because under the circumstances it
would be somewhat cooler.

1874.] The Past History of our Moon. 311

the known portions of the earth’s crust.* In the case of
the moon, whose mean density is very little greater than the
mean density of the matter forming the earth’s crust, we
must assume that the matter forming the solid nucleus at
that early stage was relatively less in amount, or else that
we may attribute part of the difference to the comparatively
small force with which lunar gravity operated during various
stages of contraction and solidification.

In,the case of the moon, as in that of the earth, before
the last portions became solidified, there would exist a con-
dition of imperfect liquidity, as conceived by Hopkins,
*‘ preventing the sinking of the cooled and heavier particles,
and giving rise to a superficial crust, from which solidification
would proceed downwards. There would thus be enclosed
between the inner and outer solid parts a portion of uncon-
gealed matter,” which may be supposed to have retained its
liquid condition to a late period, and to have been the princi-
pal seat of volcanic action, whether existing in isolated
reservoirs or subterranean lakes, or whether, as suggested
by Scrope, forming a continuous sheet surrounding the solid
nucleus.

Thus far we have had to deal with relations more or less
involved in doubt. We have few means of forming a satis-
factory opinion as to the order of the various changes to
which, in the first stages of her existence as a planet, our
moon was subject. Nor can we clearly define the nature of
those changes. In these matters, as with the corresponding
processes in our earth’s case, there is much room for variety
of opinion.

But few can doubt ee by whatever processes such ‘con-
dition may have been attained, the moon, when her surface
began to form itself into its present appearance, consisted

of a globe partially molten surroundéd by a crust at least |

partially solidified. Some portions of the actual surface
may have remained liquid or viscous later than others; but
at length the time must have arrived when the radiating
surface was almost wholly solid. It isfrom this stage that
we have to trace the changes which have led to the present
condition of the moon’s surface.

It can scarcely be questioned that those seismologists are
in the right who have maintained in recent times the theory

* It is thus, and not by the effets due to increasing pressure (effets which
do not increase beyond a certain point) that we are to explain the fac that
the earth’s density as a whole is about twice the mean density of the matters
which form its solid surface. It may be that this consideration, supported by the
results of recent experimental researches, may give a significance hitherto not
noted to the relatively small mean density of the moon.

312 The Past History of our Moon. (July,

that in the case of a cooling globe, such as the earth or
moon at the stage just described, the crust would in the
first place contract more quickly than the nucleus, while
later the nucleus would contra¢t more quickly than the crust.
This amounts, in fact, to little more than the assertion that
the process of heat radiation from the surface would be more

rapid, andso lastashortertime than the process of conduétion |

by which in the main the nucleus would part with its heat.
The crust would part rapidly with its heat, contra¢ting upon
the nucleus ; but the very rapidity (relative) of the process,
by completing at an early stage the radiation of the greater
portion of the heat originally belonging to the crust, would
cause the subsequent radiation to be comparatively slow,
while the conduction of heat from the nucleus to the crust
would take place more rapidly, not only relatively but
actually.

Now it is clear that the results accruing during the two
stages into which we thus divide the cooling of the lunar
globe would be markedly different. During the first stage
forces of tension (tangential) would be called to play in the
lunar crust ; during the later stage the forces would be those
of pressure.

Taking the earlier stage, during which the forces would
be tensional, let us consider in what way these forces would
operate.

At the beginning, when the crust would be comparatively
thin, I conceive that the more general result of the rapid
contraction of the crust would be the division of the crust
into segments, by the formation of numerous fissures due to
the lateral contraction of the thin crust. The molten mat-
ter in these fissures would film over rapidly, however, and
all the time the crust would be growing thicker and thicker,
until at length the formation of distin¢ét segments would no
longer be possible. The thickening crust, plastic in its lower
strata, would now resist more effectively the tangential ten-
sions, and when yielding would yield in a different manner.
At this stage, in all probability, it was that processes such
as those illustrated by Nasmyth’s globe experiments took
place, and that from time to time the crust yielded at parti-
cular points, which became the centres of systems of radiating
fissures. Before proceeding, however, to consider the results
of such processes, let it be noted that we have seen reason
to believe that among the very earliest lunar formations
would be rifts breaking the ancient surface of the lunar crust.
I distinguish in this way the ancient surface from portions
of surface whereof I shall presently have to speak as formed
at a later time.

1874.] The Past History of our Moon. Bhs

Now let us conceive the somewhat thickened crust con-
tracting upon the partially fluid nucleus. If the crust were
tolerably uniform in strength and thickness we should expect
to find it yielding (when forced to yield) at many points, dis-
tributed somewhat uniformly over its extent. But this
would not be the case if—as we might for many reasons
expect—the crust were wanting in uniformity. There would
be regions where the crust would be more plastic, and so
readier to yield to the tangential tensions. Towards such
portions of the crust the liquid matter within would tend,
because there alone would room exist for it. The down-
drawing, or rather in-drawing, crust elsewhere would force
away the liquid matter beneath, towards such regions of less
resistance, which would thus remain at (and be partly forced
to) ahigherlevel. At length, however, the increasing tensions
thus resulting would have their natural effect; the crust
would break open at the middle of the raised region, and in
radiating rifts, and the molten matter would find vent through
the rifts as well as at the central opening. The matter so
extruded, being liquid, would spread, so that—though the
radiating nature of the rifts would still be indicated by the
position of the extruded matter—there would be no abrupt
changes of level. It is clear, also, that so soon as the out-
let had been formed the long and slowly sloping sides of the
region of elevation would gradually sink, pressing the liquid
matter below towards the centre of outlet, whence it would
continue to pour out so long as this process of contraction
continued. All round the borders of the aperture the crust
would be melted, and would continue plastic long after the
matter which had filled the fissures and flowed out through
them had solidified. Thus there would be formed a wide
circular orifice, which would from the beginning be consider-
ably above the mean level of the moon’s surface, because of
the manner in which the liquid matter within had been
gathered there by the pressure of the surrounding slopes.*

* T have occasion to make some remarks at this stage to avoid possible and
(my experience has shown me) not altogether improbable misconception, or
even misrepresentation. The theory enunciated above will be regarded by
some, who may haye read a certain review of my Treatise on the Moon, as
totally different from what I have advocated in that work, and, furthermore, as
a theory which I have borrowed from the aforesaid review. I should not be
particularly concerned if I had occasion to modify views I had formerly ex-
pressed, since I apprehend that every active student of science should hope,
rather than dread, that as his work proceeds he would form new opinions.
And again, Iam not in the least anxious to claim priority as to the enunciation
of any theory, conceiving that claims of the kind seem as a rule indicative of
a singular poverty of intellect on the part of those who make them (as though,
having given birth to one good thought, they had no hope of ever being

314 The Past History of our Moon. [July,

Moreover, around the orifice, the matter outflowing as the
crust continued to contract would form a raised wall. Until
the time came when the liauid nucleus began to contract
more rapidly than the crust, the large crateriform orifice

delivered of another). Accordingly I have never, on the one hand, found occasion
—to the best of my recollection—to claim a disputed priority; nor, on the
other, have I ever been unwilling to abandon a theory which I have formerly
maintained on insufficient grounds. (I need only point to my article on
“Mars,” in the “ Quarterly Journal of Science,’ for April, 1873, as an illus-
trative instance, since I there not only abandon a theory I had once regarded
with favour, but advocate carefully the theory advanced against it.) But the
present instance is a somewhat peculiar one. In the “ Saturday Review ” for
March 28th there is a paper which discusses lunar phenomena with consider-
able acumen. Of course there is the giant-making process which in the
‘‘Saturday Review” always precedes the process of giant-killing. The
work of Messrs. Nasmyth and Carpenter is very warmly praised as a pre-
liminary to the annihilation of their fundamental hypothesis. ‘* We honour,”
says the condescending reviewer, ‘‘the courage which is daunted by no diffi- -
culty, and we feel that the authors were bound to make their theory a complete
one; but we should have not the less felt bound to point out the glaring
absurdities of this hypothesis had not the more than diffident tone in which
the authors themselves speak of it rendered such a proceeding unnecessary.”
I am treated somewhat differently. A theory which I touched on first in these
pages—the theory, namely, that some of the lunar markings on the moon’s
surface may have been due to meteoric downfalls in the long past ages
when that surface was plastic, and meteor flights were more important than now
—is described as one which ‘‘ Mr. Proctor would have us believe,” although I
said in so many words ‘‘that I should certainly not care to maintain that as
the true theory ;”’ and is then summarily dismissed as a facetia. But while I
am thus credited with insistance on a theory which I merely sketched as one
not to be altogether overlooked in discussing peculiarities as yet not satisfac-
torily interpreted, the reviewer wholly omits to mention that much earlier in
my book I had advocated, in a much more definite manner, a view closely re-
sembling (so far as it relates to the large craters) that which he himself advances
as preferable to Nasmyth’s. I quote in full the passage in which I indicate
and advocate, briefly but clearly, the theory urged above. At page 255 of my
work on the “* Moon,” after describing the radiations from Tycho and other
craters, I proceed—*‘ It appears to me impossible to refer these phenomena to
any general cause but the reaction of the moon’s interior overcoming the ten-
sion of the crust, and to this degree Nasmyth’s theory seems correct; but it
appears manifest, also, that the crust cannot have been fractured in the ordi-
nary sense of the word. Since, however, it results from Mallet’s investigations
that the tension of the crust is called into play in the earlier stages of con-
traction, and its power to resist contraction in the later stages,—in other words,
since the crust at first contracts faster than the nucleus, and afterwards not so
fast as the nucleus,—we may assume that the radiating systems were formed
in so early an era that the crust was plastic. And it seems reasonable to con-
clude that the outflowing matter would retain its liquid condition long enough
(the crust itself being intensely hot) to spread widely,—a circumstance which
would account at once for the breadth of many of the rays, and for the restora-
tion of level to such a degree that no shadows are thrown. It appears
probable, also, that not only (which is manifest) were the craters formed later
which are seen around and upon the radiations, but that the central crater
itself acquired its actual form long after the epoch when the rays were formed.”
It will be manifest that the method here indicated as that by which the central
crater acquired its actual form long after the rays had been formed, could only
be that which the reviewer has indicated in the following passage :—‘t Assuming
that the moon was once covered by a crust of rock, under a portion of which

1874.] The Past History of ouv Moon. 315

would be full to the brim (or nearly so), at all times, with
occasional overflows; and as a writer who has recently
adopted this theory has remarked—‘‘ We should ultimately
have a large central lake of lava surrounded by a range of
hills, terraced on the outside,—the lake filling up the space
taey enclosed.”

The crust might burst in the manner here considered, at
several places at the same—or nearly the same—time, the
range of the radiating fissures depending on the extent of
the underlying lakes of molten matter thus finding their
outlet; or there might be a series of outbursts at widely
separated intervals of time, and at different regions, gradually
diminishing in extent as the crust gradually thickened and
the molten matter beneath gradually became reduced in
relative amount. Probably the latter view should be ac-
cepted, since if we consider the three systems of radiations
from Copernicus, Aristarchus, and Kepler, which were
manifestly not formed contemporaneously, but in the order
in which their central craters have just been named, we see
that their dimensions diminished as their date of formation
was later. According to this view we should regard the
radiating system from Tycho as the oldest of all these
formations.

At this very early stage of the moon’s history, then,
we regard the moon as a somewhat deformed spheroid,
the regions whence the radiations extended being the
highest parts, and the regions farthest removed from the
ray centres being the lowest.* To these lower regions what-
ever was liquid on the moon’s surface would find its way.
The down-flowing lava would not be included in this descrip-
tion, as being rather viscous than liquid; but if any water

at least lay melted rock of the same nature, nothing is more natural than that
the contraction of the crust should cause great overflows of lava, which would
spread far and wide; the outside portions would cool, but those near the
centre of disturbance would be kept at. their original temperature, and the
tendency would be (as is so often noticed in eruptions) to melt the already
solidified rock with which it was in conta@, and thus the orifice would become
wider.”

* Where several ray centres are near together, a region dire@ly between
two ray centres would be at a level intermediate between that of the ray
centres and that of a region centrally placed within a triangle or quadrangle of
tay centres; but the latter region might be at a higher level than another very
far removed from the part where the ray centres were near together. For in-
stance, the space inthe middle of the triangle having Copernicus, Aristarchus,
and Kepler at its angles (or more exactly between Milichius and Bessarion) is
lower than the surface around Hortensius (between Copernicus and Kepler),
but not so low as the Mare Imbrium, far away from the region of ray centres
of which Copernicus, Aristarchus, and Kepler are the principal.

316 The Past History of our Moon. (July,

existed at that time it would occupy the depressed regions
which at the present time are called Maria or Seas. Itisa
question of some interest, and one on which different
opinions have been entertained, whether the moon at any
stage of its existence had oceans and an atmosphere corre-
sponding or even approaching in relative extent to those of
the earth. It appears to me that, apart from all the other
considerations which have been suggested in support of the
view that the moon formerly had oceans and an atmosphere,
it is exceedingly difficult to imagine how, under any circum-
stances, a globe so large as the moon could have been formed
under conditions not altogether unlike, as we suppose, those
under which the earth was formed (having a similar origin,
and presumably constructed of the same elements), without
having oceans and an atmosphere of considerable extent ;
the atmosphere would not consist of oxygen and nitrogen
only or chiefly, any more than, in all probability, the primzval
atmosphere of our own earth was so constituted. We may
adopt some such view of the moon’s atmosphere—mutatis
mutandis—as Dr. Sterry Hunt has adopted respecting the
ancient atmosphere of the earth. Hunt, it will be remem-
bered, bases his opinion on the former condition of the earth
by conceiving an intense heat applied to the earth as now
existing, and inferring the chemical results. ‘‘To the
chemist,” he remarks, “‘ it is evident that from such a process
applied to our globe would result the oxidation of all carbon-
aceous matter; the conversion of all carbonates, chlorides,
and sulphates into silicates; and the separation of the car-
bon, chlorine, and sulphur in the form of acid gases ; which,
with nitrogen, watery vapour, and an excess of oxygen,
would form an exceedingly dense atmosphere. The resulting
fused mass would contain all the bases as silicates, and
would probably nearly resemble in composition certain
furnace-slags or basic volcanic glasses. Such we may con-
ceive to have been the nature of the primitive igneous rock,
and such the composition of the primeval atmosphere, which
must have been one of very great density.” All this, with the
single exception of the italicised remark, may be applied to
the case of the moon. The lunar atmosphere would not
probably be dense at that primeval time, even though con-
stituted like the terrestrial atmosphere just described. It
would perhaps have been as dense, or nearly so, as our pre-
sent atmosphere. Accordingly condensation would take
place at a temperature not far from the present boiling-
point, and the lower levels of the half-cooled crust would be
drenched with a heated solution of hydrochloric acid, whose

1874.] The Past History of owr Moon. 317

decomposing action would be rapid, though not aided—as
in the case of our primeval earth—by an excessively high
temperature. ‘‘ The formation of the chlorides of the
various bases and the separation of silica would go on until
the affinities of the acid were satisfied.” ‘* At a later period
the gradual combination of oxygen with sulphurous acid
would eliminate this from the atmosphere in the form of
sulphuric acid.” ‘‘ Carbonic acid would still be a large con-
stituent of the atmosphere, but thenceforward (that is, after
the separation of the compounds of sulphur and chlorine
from the air) there would follow the conversion of the com-
plex aluminous silicates, under the influence of carbonic
acid and moisture, into a hydrated silicate of alumina or clay,
while the separated lime, magnesia, and alkalies would be
changed into bicarbonates, and conveyed to the sea in a state
of solution.”

It seems to me that it is necessary to adopt some such
theory as to the former existence of lunar oceans, in order
to explain some of the appearances presented by the so-
called lunar seas. As regards the present absence of water
we may adopt the theory of Frankland, that the lunar
oceans have withdrawn beneath the crust as room was pro-
vided for them by the contraction of the nucleus. I think,
indeed, that there are good grounds for looking with favour
on the theory of Stanislas Meunier, according to which the
oceans surrounding any planet—our own earth or Mars, for
example—are gradually withdrawn from the surface to the
interior. And in view of the enormous length of the time
intervals required for such a process, we must consider that
while the process was going on the lunar atmosphere would
not only part completely with the compounds of sulphur,
chlorine, and carbon, but would be even still further reduced
by chemical processes acting with exceeding slowness, yet
effectively in periods so enormous. But without insisting
on this consideration, it is manifest that—with very
reasonable assumptions as to the density of the lunar atmo-
sphere in its original complex condition—what would remain
after the removal of the chief portion by chemical processes,
and after the withdrawal of another considerable portion
along with the seas beneath the lunar crust, would be so in-
considerable in quantity as to accord satisfactorily with the
evidence which demonstrates the exceeding tenuity of any
lunar atmosphere at present existing.

These considerations introduce us to the second part of
the moon’s history,—that corresponding to the period when
the nucleus was contracting more rapidly than the crust.

VOL. IV. (N.S.) 25

318 The Past History of our Moon. (July,

One of the first and most obvious effects of this more
rapid nuclear contraction would be the lowering of the level
of the molten matter, which up to this period had been kept
up to, or nearly up to, the lips of the great ringed craters.
If the subsidence could place intermittently there would
result a terracing of the interior of the ringed elevation,
such as we see in many lunar craters. Nor would there be
any uniformity of level in the several crater floors thus
formed, since the fluid lava would not form parts of a single
fluid mass (in which case, of course, the level of the fluid
surface would be everywhere the same), but would belong to
independent fluid masses. Indeed it may be noticed that
the very nature of the case requires us to adopt this view,
since no other will account for the variety of level observed
in the different lunar crater-floors. If these ceased to be liquid
at different times, the independence of the fluid masses is
by that very fact established; and if they ceased to be liquid
at the same time, they must have been independent, since,
if communication had existed between them, they would
have shown the uniformity of surface which the laws of
hydrostatics require.*

The next effect which would follow from the gradual re-
treat of the nucleus from the crust (setting aside the with-
drawal of lunar seas) would be the formation of corrugations,
—in other words, of mountain-ranges. Mallet describes the
formation of mountain-chains as belonging to the period
when “the continually increasing thickness of the crust re-
mained such that it was still as a whole flexible enough, or
opposed sufficient resistance of crushing to admit of the
uprise of mountain-chains by resolved tangential pressures.”
Applying this to the case of the moon, I think it is clear
that—with her much smaller orb and comparatively rapid
rate of cooling—the era of the formation of mountain-chains
would be a short one, and that these would therefore form a
less important characteristic of her surface than of the
earth’s. On the other hand, the period of volcanic activity
which would follow that of chain-formation would be
relatively long continued; for regarding this period as begin-
ning when the thickness of the moon’s crust had become too
great to admit of adjustment by corrugation, the compara-
tively small pressure to which the whole mass of the moon
had been subjected by lunar gravity, while it would on the
one hand cause the period to have an earlier commencement

* It is important to notice that we may derive from these considerations an
argument as to the condition of the fluid matter now existing beneath the solid
crust of the earth.

1874.] The Past History of our Moon. 319

(relatively), and on the other would leave greater play to the
effects of contraction. Thus we can understand why the
signs of volcanic action, as distinguished from the action to
which mountain-ranges are due, should be far more nume-
rous and important on the moon than on the earth.

I do not, however, in this place enter specially into the
consideration of the moon’s stage of volcanic activity, be-
cause already, in the pages of my Treatise on the Moon
(Chapter VI.) I have given a full account of that portion of
my present subject. I may make a few remarks, however,
on the theory respecting lunar craters touched on in my
work on *‘ The Moon.” I have mentioned the possibility that
some among the enormous number of ring-shaped de-
pressions which are seen on the moon’s surface may have
been the result of meteoric downfalls in long past ages of
the moon’s history. One or two critics have spoken of this
view as though it were too fantastic for serious consideration.
Now, though I threw out the opinion merely as a suggestion,
distinctly stating that I should not care to maintain it as a
theory, and although my own opinion is unfavourable to the
supposition that any of the more considerable lunar markings
can be explained in the suggested way, yet it is necessary to
notice that on the general question whether the moon’s
surface has been marked or not by meteoric downfalls
scarcely any reasonable doubts can be entertained. For,
first, we can scarcely question that the moon’s surface was
for long ages plastic, and though we may not assign to this
period nearly so great a length (350 millions of years) as
Tyndall—following Bischoff—assigns to the period when
our earth’s surface was cooling from a temperature of
2000 C. to 200, yet still it must have lasted millions of
years; and, secondly, we cannot doubt that the process of
meteoric downfall now going on is not a new thing, but, on
the contrary, is rather the final stage of a process which
once took place far more actively. Now Prof. Newton has
estimated, by a fair estimate of observed facts, that each day
on the average 400 millions of meteors fall, of all sizes down
to the minutest discernible in a telescope, upon the earth’s
atmosphere, so that on the moon’s unprotected globe—with
its surface one-thirteenth of the earth’s—about 30 millions
fall each day, even at the present time. Of large meteoric
masses only a few hundreds fall each year on the earth, and
perhaps about a hundred on the moon; but still, even at the
present rate of downfall, millions of large masses must have
fallen on the moon during the time when her surface was
plastic, while presumably a much larger number—including

320 Tropical Zoology. (July,

many much larger masses—must have fallen during that
period. Thus, not only without straining probabilities, but
by taking only the most probable assumptions as to the
past, we have arrived at a result which compels us to
believe that the moon’s surface has been very much marked
by meteoric downfall, while it renders it by no means un-
likely that a large proportion of the markings so left would
be discernible under telescopic scrutiny; so that strong
evidence exists in favour of that hypothesis which one or
two writers (who presumably have not given great attention
to the recent progress of meteoric astronomy) would dismiss
‘without consideration ” (the way, doubtless, in which they
have dismissed it).

I would, in conclusion, invite those who have the requisite
leisure to a careful study of the distribution of various orders
of lunar marking. It would be well if the moon’s surface
were isographically charted, and the distribution of the seas,
mountain-ranges, and craters of different dimensions and
character, of rills, radiating streaks, bright and dark regions,
and so on, carefully compared inter se, with the object of
determining whether the different parts of the moon’s sur-
face were probably brought to their present condition during
earlier or later periods, and of interpreting also the signifi-
cance of the moon’s characteristic peculiarities. In this
department of Astronomy, as in some others, the effective-
ness of well-devised processes of charting has been hitherto
overlooked.

i

IV. MODERN RESEARCHES IN TROPICAL
ZOOLOGY.*

feed modern books of travel are justly ranked
among the dreariest of literary productions. ‘Their
authors treat the countries which they visit merely
as a stage for the display of their own imagined perfections,
their omniscience, their courage, their skill as sportsmen,
and above all, the importance of their mission to the dis-
tinguished personages with whom they became acquainted.
To all this the work before us offers a complete and a
delightful contrast. Mr. Belt does not obtrude his own
personality upon us. Like all genuine men, he forgets
‘‘self” over his subject. Instead of informing us whether

rw”

*The Naturalist in Nicaragua; a Narrative of a Residence at the Gold Mines
of Chontales, By Tuomas BELT, F.G.S. London: John Murray.

1874.] Tropical Zoology. 321

or no he received ‘‘the salary of an ambassador and the
treatment of a gentleman,” he scatters before us, broadcast,
facts, interesting and novel; valuable hints for future re-
search, and generalisations which will amply repay a close
examination. Not alone the zoologist, the botanist, the
geologist, but the antiquarian, the ethnologist, the social
philosopher, and the meteorologist, will each find in these
pages welcome additions to his store of knowledge and sound
materials for study. With all this, the work is not a mere
dry catalogue of facts, such as Henry Cavendish might
have written: it is eminently a “‘ readable book.” ‘Though
without any effort at fine writing, the beautiful forest land-
scapes of Central America are brought vividly before us.
For instances, we refer our readers to the work itself.

In his professional investigations of the gold deposits of
Chontales, the author was struck with the scarcity of
alluvial gold in the valleys, even in the neighbourhood of
rich veins of auriferous quartz. This fact, reminding the
observer of the similar scarcity in the valleys of Nova Scotia
and North Wales, can be explained ‘‘on the supposition
that the ice of the glacial period was not confined to extra-
tropical lands, but, in Central America, covered all the
higher ranges and descended to at least as low as the line of
country now standing at two thousand feet above the sea,
and probably much lower.” That glaciers would have this
‘effect is indubitable. As the author remarks: ‘‘ When the
denuding agent was water, the rocks were worn away, and
the heavier gold left behind at the bottom of the alluvial
deposits; but when the denuding agent was glacier-ice, the
stony masses and their metallic contents were carried away,
or mingled together in the unassorted moraines.”

We may, at first sight, feel sceptical concerning the ex-
istence of glaciers in the low grounds within 13° of the
equator. But the testimony of the rocks appears irresist-
ible. ‘‘ The evidences of glacial action were as clear as in
any Welsh or Highland valley. There were the same
rounded and smoothed masses of rock, the same moraine-
like accumulations of unstratified sand and gravel, the same
transported boulders that could be traced to their parent
rocks, several miles distant.’’ Glacial scratches were not,
indeed, observed; but these are rarely detected on surfaces
of rock exposed to the atmosphere. We must, also, remem-
ber that Professor Hart has found glacial drift extending
from Patagonia all through Brazil to Pernambuco, whilst
the late lamented Agassiz has observed glacial moraines up
to the equator. On a former journey Mr. Belt discovered in

322 Tropical Zoology. (July,

the province of Maranham, in Brazil, a great drift deposit
apparently of glacial origin. Hence, he, very justifiably,
thinks it highly probable that the ice deposits of the glacial
period were far more extensive than has been generally
supposed, existing at once in both the northern and southern
hemispheres, and leaving, in America at least, only the
lower lands of the tropics free from the icy covering.

Were the causes of such a redu¢tion of the earth’s general
temperature cosmic or merely terrestrial? ‘The author does
not enter minutely into this question, though, with Professor
Heer, he considers that the cold of the glacial period, like
the warmth of the miocene epoch, ‘‘ cannot be explained by
any re-arrangement of the relative positions of land and
water.” It is very true that were the circum-polar lands,
British North America and the Russian empire, deeply sub-
merged beneath the ocean, and were a corresponding amount
of land raised where now rolls the inter-tropical Pacific, the
temperature of the world would be much ameliorated. But
the very evidence of the heat of the miocene ages,—the
existence, at that time of the beech, the hazel, and the plane
in Spitzbergen, in north latitude 78°, proves that the polar
regions were not an unbroken expanse of water. Similarly,
the proofs of glacial action within the torrid zone show that
during the glacial period land was by no means wanting
between the tropics. It seems, therefore, highly probable,

that in regarding these alternating epochs of heat and cold,

‘‘we are face to face with a problem whose solution must
be attempted, and doubtless completed, by the astronomer.”

But there is another phase of the subject to which the
attention of the author is mainly given. Every botanist and
geologist, on hearing of these enormous ice-deposits in what
are now some of the most luxuriant climates of the world,
will ask what must have become of all tropical forms of
organic life? The very tierras calientes in those days, in-
stead of towering palms and of epiphytal arads and orchids,
must have possessed a vegetation little richer than that of
England or Germany in the present order of things.
Heliconii and Morphos can never have unfolded their
delicate wings on the chill blast from the ice-deserts. The
author meets this difficulty by the hypothesis that “a
refuge was found for many species on lands now below the
level of the ocean, but then uncovered by the lowering of
the sea, consequent upon the immense quantity of water
locked up in the form of ice, and piled upon the continents.”
A variety of evidence is adduced in support of this view.
The distribution of animal life over small islands now

1874.| Tropical Zoology. 323

separated by shallow seas is readily explained on such
supposition. Professor Hartt found reason to believe that
during the time of the drift, Brazil stood at a much higher
level than at present. Mr. Alfred Tylor considers that
during the glacial epoch the level of the sea must have been
reduced at least 600 feet, an estimate which our author
extends to 1000. Mr. Wallace, in his work on the Malay
Archipelago, infers from the distribution of animal life that
Borneo, Java, and the more western islands of the group
were at one time connected with each other, and with the
main land of Asia, while New Guinea and the islands to the
eastward were joined to Australia. The Cyclopean ruins
found in certain islets of the Pacific, and utterly out of
keeping with their present size and population, point in the
same direction. Easter Island, as the author observes,
could never have supported the race that reared such
monuments. But if the present island was once one of a
chain of hills overlooking wide and populous lowlands—now
submerged beneath the blue waters of the Pacific—such
remains become intelligible.

Mr. Belt’s theory, as we may provisionally call it, furnishes
the key to a number of ancient traditions on both sides of
the Atlantic.

May not the Atlantis of Plato, of Theopompus, and of
Proclus, finally swallowed up by the sea, have been “that
great continent in the Atlantic, on which the present West
Indian Islands were mountains?” The warlike and pre-
datory character ascribed to its inhabitants by Greek and
Egyptian story is in full harmony with their probably Carib
origin. Mr. Belt’s theory throws also a wonderful light upon
the sagas of a universal deluge current, according to Catlin,
among one hundred and twenty different tribes of North and
South America. Those low-lying lands, if they existed at
all, must have been the refuge during the glacial epoch, not
merely of the principal forms of vegetable and animal life,
but of the human race. Whatever civilisation existed must
have had there its seat. Suppose, now, that the temperature
of the earth experienced, from some unknown cosmical
cause, a sudden elevation. The glaciers, or rather the ice-
caps, resting on the present continents, are suddenly con-
verted into torrents of water rushing down to the sea. The
ocean level rapidly rises. Atlantis and all the other
populous regions of the earth are engulphed. A hundred
fathoms deep roll the waters over fields and cities, whilst a
few only of the inhabitants escape in boats or find shelter
on some lofty mountain.

324 Tropical Zoology. (July,

Much, however, requires to be done, before such a theory
can claim recognition among the established doétrines of
science. Mr. Belt himself insists on the necessity of a
careful and thorough going verification of his hypothesis.
** When geologists have mapped out the limits of ancient
glacier and continental ice all over the world, it will be
possible to calculate the minimum amount of water that
was abstracted from the sea; and if by that time hydro-
graphers have shown on their charts the shoals and sub-
merged banks that would be laid dry, fabled Atlantis
will rise before our eyes between Europe and America, and
in the Pacific the Malay Archipelago will give place to the
Malay continent.” In our opinion, a knowledge of the
distribution of animal life, much more accurate and general
than we now possess, will also be found needful for the full
solution of the problem. Is it not also possible that by a
careful examination of the less deeply submerged banks and
shoals, evidence as to the presence or absence of traces of
former human activity might be obtained ?

We must not, however, forget that Mr. Belt’s interesting
hypothesis is not without a rival. The doctrine of areas of
subsidence and elevation so ably expounded by Mr. Darwin
in his Naturalists’ Voyage, accounts for many of the same
phenomena by an alteration of the level, not of the sea, but
of the continents, and certainly agrees with many recognised
facts. We have not space to examine in how far the two
theories are necessarily antagonistic and mutually exclusive.
It is plain that some of the Pacific Islands—which accord-
ing to both views are the mountains of a now submerged
continent—are still gradually subsiding. It is no less
manifest that other portions of the earth’s surface, e¢.g.,
certain parts of the South American coast, are gradually
rising. The evidence of both these progressive variations
of level may be found in the above-mentioned work of Mr.
Darwin. ‘The phenomena of the atolls, likewise, appear to
us to agree better with the assumption of a gradual subsi-
dence of the dry land than with its inundation by the
sudden influx of water. On the other hand, the Beltian
hypothesis, harmonises best with the deluge-traditions of
the old and the new world.

On Mr. Belt’s view, we should naturally expect to find
the fauna and the flora of any large island closely corres-
pond to that of the adjacent continent, with which during
the glacial period it would have been connected. Yet to
this rule—if rule it be—there are notable exceptions of which
account must be taken. Why should the larger Antilles be

1874.] Tropical Zoology. 325

free from carnivora? Cuba and Haiti would have afforded,
in their glens and woods, ample and congenial lurking-
grounds for the jaguar and the puma. Nor, to our know-
ledge, have these islands ever been so populous and so
civilised that such unwelcome inmates would have been
extirpated. Ceylon is separated from the mainland of India
by a shallow sea. If the general level of the waters were
reduced by 1000, or even by 600 feet, the space between the
island and the continent would be bridged over. Yet, on
the authority of Sir E. Tennant, there are more points of
disagreement than of resemblance between the respective
animal and vegetable forms on both sides of the straits.
We are not aware of the depth of the Channel of the
Mozambique. But scarcely could two richly developed
faunas differ more strikingly than those of Madagascar and
of South-eastern Africa. The monkeys of the continent
are, in the island, replaced by lemurs. The cats and the
gazelles in which Africa abounds are, we believe, totally
wanting in Madagascar. The inse¢t-world in particular
shows a striking divergence. Madagascar is remarkably
rich in those “‘ animated jewels,” the Cetoniade; but the
species, and for the most part the genera, are distin@t from
those of Southern Africa, and, where not peculiar, remind
us rather of forms developed in the Malay Archipelago.

But Mr. Belt’s work is so replete with interest that we
must, unwillingly indeed, desist from any further scrutiny of
his geological speculations. His instances of the intelligence
of ants are highly instructive :—‘‘One day when watching a
small column of these ants (Eciton hamata) I placed a
little stone on one of them to secure it. The next that
approached, as soon as it discovered its situation, ran
backwards in an agitated manner and soon communicated
the intelligence to the others. They rushed to the rescue;
some bit at the stone and tried to move it, others seized the
prisoner by the legs and tugged with such force that I
thought the legs would be pulled off, but they persevered
till they got the captive free. I next covered one up with a
piece of clay, leaving only the ends of its antenne projeCt-
ing. It was soon discovered by its fellows, which set to
work immediately, and by biting off pieces of the clay, soon
liberated it. Another time I found a very few of them
passing along at intervals. I confined one of these under a
piece of clay, at a little distance from the line, with its head
projecting. At last an ant discovered it and tried to pull it
out, but could not. It immediately set off at a great rate,
and I thought it had deserted its comrade, but it had only

WOES AV. (N.S.) 2.7

326 Tropical Zoology. [July,

gone for assistance, for in a short time about a dozen ants
came hurrying up, evidently fully informed of the circum-
stances of the case, for they made directly for their im-
prisoned comrade and soon set him free. I do not see how
this action could be instinctive. It was sympathetic help,
such as man only among the higher mammalia shows.”

We need not feel surprised if an observer accustomed to
scrutinise the animal world so closely feels sceptical on the
subject of ‘‘instinét.” That notion is all very well for
literateurs, lawyers, divines, or poets, who dabble a little in
zoology, or for mere closet book-worms, who only catch a
faint refleCtion of facts. But the naturalist of the field and
the forest, though he recognises zmstincts in the lower
animals, as in man himself, can but smile at ‘“‘ zmstinct,”
viewed as a mysterious entity, antithetically opposed to
reason and supposed to act as its substitute in ‘‘ our poor
relations.” The mutual helpfulness of ants is the more
significant since, amongst social mammalia and birds, the
tribe generally attack and put to death any of their number
that suffers from an accident. The author gives two more
instances of reason in ants. “I once saw a wide column
trying to pass along a crumbling, nearly perpendicular slope.
They would have got very slowly over and many of them
would have fallen, but a number having secured their hold
and reaching to each other, remained stationary, and over
them the main column passed. Another time they were
crossing a water-course along a small branch, not thicker ©
than a goose-quill. They widened this natural bridge to
three times its width by a number of ants clinging to it and
to each other on each side, over which the column passed
three or four abreast ; whereas, excepting for this expedient,
they would have had to pass over in single file and triple the
time would have been consumed.” In face of such facts the
author asks—‘‘ Can it be contended that such insects are
not able to determine by reasoning powers which is the best
way of doing a thing, or that their actions are not guided by
thought and reflection?’ This view is much strengthened
by the fact that the cerebral ganglia are more developed in
ants than in any other insect, and that in all the Hymenop-
tera, at the head of which they stand, they are many times
larger than in the less intelligent orders, such as beetles, or,
we might add, than in those short-lived emblems of immor-
tality, the butterflies.

Again, ‘‘amongst the ants of Central America, I place
the Eciton as the first in intelligence, and as such, at the
head of the Articulata. Wasps and bees come next, and

1874.] Tropical Zoology. 327

then others of the Hymenoptera. Between ants and the
lower forms of insects there is a greater difference in
reasoning powers than there is between man and the lowest
mammalian. A recent writer (Houzeau) has augured that
of all animals ants approach nearest to man in their social
condition. Perhaps if we could learn their wonderful lan-
guage we should find that even in their mental condition
they also rank next to humanity.”

As regards their social condition ants differ from us in
having successfully established communism. At the present
day all the social Hymenoptera must be viewed with intense
interest on account of their working-order or neuters. These,
as 1s well known, are females whose normal development
has been checked. Are we to assume that ‘‘once upon a
time”? a woman’s rights movement sprung up in bee-hives
and ant-hills, which ended in reducing the males to a very un-
important position, and in limiting the number of the fully
developed females? Are we to expect that the “‘ strong
minded” ladies who are now arising among us are the
forerunners of a ‘“‘neuter”’ order, and the heralds of a corres-
ponding change in human society ?

‘“The Hymenoptera standing at the head of the Articulata,”
resumes our author, ‘‘ and the Mammalia at the head of the
Vertebrata, it is curious to mark how in Zoological history
the appearance and development of these two orders (cul-
minating, the one in the ants, and the other in the primates)
run parallel. The Hymenoptera and the Mammalia both
make their first appearance early in the secondary period,
and it is not until the commencement of the tertiary epoch
that ants and monkeys appear upon the scene.”

Just as in a chain of mountains the second highest peak
is often far remote from the culminating point, so it is in
the upheaval of the animal world to reason. The position
of a being in the zoological series, or its proximity in
structure to man, bears no relation to its degree of in-
telligence.

Warm as is Mr. Belt’s interest in ants in general, and
the Eciton in particular, he does not overlook the fact that
to man they are a great nuisance. Their habits of biting off
the leaves of trees, and of fostering and defending such
vermin as plant-lice, are, from our point of view, highly
objectionable. It is, therefore, a fortunate circumstance
that carbolic acid and corrosive sublimate afford us the
means of putting a stop to their depredations. Mr. Belt’s
experiments with reference to this subject are well worth
the attention of tropical agriculturists.

328 Tropical Zoology. (July,

The great bulk of our author’s observations on animals
and plants have been made, as the title-page informs us,
‘in reference to the theory of evolution of living forms,”—
in other words, to the views popularly included under the
name Darwinism. ‘These views can scarcely be said to have
met with fair treatment. They have been dolefully groaned
over by certain “grave and reverend,” if not very ‘‘ potent
seigniors,” on account of their supposed ‘‘ questionable
tendencies,” almost in the very words applied in the days
of Galileo to the heliocentric theory in astronomy. They
have been sneered at by witling gallants by whom the hint
of kinship with monkeys was felt as an ‘‘ owre true joke.”
They have been “ gushed” over in the daily press by leader
writers and special correspondents whose conceptions of the
subject were of the haziest. The hostile critics of the
evolution theory have been, for the most part, not naturalists
but outsiders, incapabable of entering into the full meaning
of the evidence. To take a case strictly analogous, what
should we think of a lawyer who in a difficult and com-
plicated matter should give a professional opinion founded
on documents drawn up in a language with which he had
but a very slight acquaintance? ‘‘ Theories,” says M.
Dumas, ‘‘are like crutches; to judge of their value we must
take them and try to walk with them.” This is what Mr.
Belt does, and all who candidly read his book must concede
that the doctrine of evolution throws a welcome light upon
many abstruse phenomena, and brings into organic connec-
tion facts which previously lay scattered in hopeless con-
fusion. Let us take for example the phenomenon of
mimetism—an unhappily chosen name—of which our author
gives some interesting instances.

A certain animal species is often found to show a super-
ficial, but still striking and deceptive, resemblance to some
other species, generally of a totally distinct group; to some
vegetable product, or even to a fragment of lifeless matter.
Instances of this are the ‘‘ walking leaves,” the moss insect,
discovered and figured by the author, which closely simulates
a few filaments of moss lying on the ground; the mimetic
bug (Spiniger luteicornis), which in form, in the colouration
of every part, and in its very movements mimics the hornet
(Priocnemis). ‘This simulation, of course involuntary, enables
the insect either to elude its enemies or to secure its prey.
Thus the bug above mentioned might fall an easy victim to
many birds and insects which would hesitate before attacking
a hornet. Hence the bug owes its safety to its resemblance
to the hornet. There is, again, a small spider which closely

1874.] Tropical Zoology. 329

simulates a black, stinging ant. Spiders are greatly sought
after and eagerly devoured by birds, whilst stinging ants are
little relished. The Heliconii, a group of butterflies very
largely developed in the West Indies and in Central America,
have in all probability an offensive flavour. Birds, monkeys,
and spiders avoid or reject them. ‘There are other butterflies,
belonging to perfectly distinct groups, which closely simulate
the Heliconii, and thus escape the beaks of birds and the
attention of spiders. The advocates of evolution explain
this mimetism by supposing that, ¢e.g., a bug by some acci-
dental variation from the normal structure of its congeners
received a slight resemblance to a hornet. Its posterity, to
whom this resemblance was transmitted, enjoyed an ad-
vantage in the struggle for existence over bugs which had
remained true to the pristine type. Those of them in which
the likeness to the hornet was most pronounced would, again,
escape best from their enemies, and would thus have the
greatest chance of becoming the progenitors of the next
generation. The opponents of evolution have no way of
accounting for mimetism beyond asserting that certain
species were, for their protection, arbitrarily and ab initio
endowed with these resemblances,—a most unsatisfactory
explanation.

The same do¢trine throws light on the difficulties often
experienced in introducing foreign plants into any country.
Thus the orange and the citron, in Central America, are very
much more exposed to the attacks of Ecitons than any
native vegetation. The reason is very simple :—‘‘ Through
long ages the trees and the ants of tropical America have
been modified together. Varieties of plants that arose un-
suitable for the ants have had an immense advantage over
others that were more suitable, and thus—through time—
every indigenous tree that has survived has done so because
it has had originally, or has acquired, some protection
against the great destroyers. The leaf-cutting ants are con-
fined to tropical America, and we can easily understand that
trees and vegetables introduced from foreign lands, where
these ants are unknown, could not have acquired—except
accidentally and without reference to the ants—any protec-
tion against them.”

If we reject the Darwinian view we should naturally infer
that in any country foreign trees would enjoy an immunity
from indigenous depredators, instead of being, as they are,
especially singled out for attack. It is a curious fact that
the leaf-cutting ants form, with the vegetable matter they
thus carry off, manure-heaps, on which they cultivate minute
fungi for the food of their larve.

330 Tropical Zoology. (July,

With regard to the origin of species we extract the fol-
lowing interesting passage :—‘‘ The great mortality among
the insects of Chontales, in 1872, has some bearing on the
origin of species, for in times of such great epidemics we
may suspect that the gradations that connect extreme forms
of the same species may become extin¢ét. Darwin has
shown how very slight differences in the colour of the skin
and hair are sometimes correlated with great immunity from
certain diseases, from the action of some vegetable poisons
and the attacks of certain parasites. Any variety of species
of insects that could withstand better than others these
great and probably periodical epidemics would certainly
obtain a great advantage over those not so protected, and
thus the survival of one form and the extin¢tion of another
might be brought about. We see two species of the same
genus, aS in many insects, differing but little from each
other, yet quite distinét, and we ask why—if these have
descended from one parent form—do not the innumerable
gradations that must have connected them exist also?
There is but one answer :—We are ignorant what characters
are of essential value to each species; we do not know why
white terriers are more subject than darker-coloured ones to
the attacks of the fatal distemper; why yellow-fleshed
peaches in America suffer more from diseases than the
white-fleshed varieties ; why white chickens are most liable
to the gapes ; or why silkworms which produce white cocoons
are not attacked by fungus so much as those which produce
yellow cocoons. Yet in all these cases, and many others, it
has been shown that immunity from disease is correlated
with some slight difference in colour or structure; but as to
the cause of that immunity we are entirely ignorant.”

In the following passage the author leads up to that phase
of Darwinism of which the political economists have been
making use :—‘‘It was this constant struggle between the
different tribes that weeded out the weak and indolent, and
preserved the strong and enterprising; just as among many
of the lower animals the stronger kill off the weaker, and
the result is the improvement of the race.”

Many persons in these days talk glibly about the “battle
of life’? and the ‘‘ survival of the fittest,” and the improve-
ment of the race. But the question may arise—Who are
the fittest ? If we look at the vegetable world we find that
the species precious to us for food, medicine, or clothing,
and the kinds which delight our senses with the grace of
their shapes, the beauty of their colours, or the delicacy of
their odours, are precisely not the forms which would come

1874.] Tropical Zoology. 331

out victorious from the struggle for existence. Were it not
for man’s constant intervention, the vine and the wheat, the
rose and the carnation, would soon succumb to a tribe of
weeds as devoid of utility as of beauty. Further, when man
takes in hand to improve any race, his first step is to stamp
out the struggle for existence, whether between individuals
of such race or between the race itself and other species.
If we examine the case of a turnip-field we find that the
number of plants is strictly proportioned to the extent of the
land, and that an unrelenting war is waged against all
weeds. Were the struggle for existence permitted to rage
unchecked we should certainly find some of the turnips
larger than others, whether in virtue of more favourable
circumstances or of more intense vitality in the seed. But
the yield from the whole plot would be trifling, and no rout
would reach the dimensions attained where every plant finds
a sufficiency of room and of nutriment. Perhaps, in like
manner, the men most valuable to the world—the discoverers
and inventors—are not those who win the ordinary prizes of
life. Perhaps society or its rulers may one day find it
necessary to take for a model the farmer’s management of
his turnip-field.

We can do no more than briefly call attention to the
author’s view of cyclones. From these terrific manifestations
of force down to the eddy of dust which we often see crossing
aroad ora common, we have, according to Mr. Belt, one
and the same phenomenon, differing merely in degree.
Hence he recommends a careful study of these small dust-
whirlwinds, as calculated to throw light upon the origin of
cyclones. His own theory, first advanced in 1857, in a paper
read before the Philosophical Institute of Victoria, is that
the particles of air next the surface do not always rise im-
mediately they are heated, but that they often remain and
form a stratum of rarefied air next the surface, which is in
a state of unstable equilibrium. ‘This continues until the
heated strata are able, at some point where the ground
favours a greater accumulation of heat, to break through
the overlying strata of air and force their way upward. An
Opening once made, the whole of the heated air moves
toward it, and is drained off, the heavier layers sinking
down and pressing it out. That hot air does not always
immediately rise is proved by the hot winds of Australia,
which blow from the heated interior towards the cooler
south, instead of rising directly upwards.

In conclusion, we feel bound to give this book our most
cordial recommendation. Few men possessing any degree

332 Annual International Exhibitions. (July,

of scientific culture will be able to read it without deriving
both pleasure and profit, or will refuse to join us in the wish
that this may not be Mr. Belt’s last appearance before the
public. It is no idle compliment to say that if he were a
man of leisure, instead of a man of bustle and business, he
would prove a worthy rival of Agassiz and of Humboidt.

V. ANNUAL INTERNATIONAL EXHIBITIONS.
By FrRepD. CuHas. DANVERS, Assoc. Inst. C.E., &c.

International Exhibitions of 1851 and 1862 were un-
mistakable evidences of the popularity: of those ~
institutions, and the public, by the support they accorded to —
them, testified plainly enough to the correctness of the
judgment which allowed a decade to elapse between the two ~
events. Another similar occurrence in 1871 or 1872 would,
no doubt, also have proved a success, notwithstanding that
intermediate exhibitions elsewhere had, to some extent, an-
ticipated the results which such an institution would have
achieved. Nothing could be more advantageous than the
establishment of a decennial exhibition of all nations, for
the purpose of exhibiting the advances made in science
during each period of ten years; but when the example
must needs be followed by France, Italy, Germany, Russia,
America, and probably other nations also, the Exhibition
necessarily becomes one of almost annual occurrence, and
the strain upon manufacturers becomes too great for en-
durance, and it soon manifested itself that such Exhibitions
were degenerating into huge advertising affairs, and they
were treated in just that light by manufacturers in general.
Hence. it was clear that the days of huge International
Exhibitions were numbered, and that it would be impossible
to extend their existence for any further lengthened period.
Whether it was from an appreciation of this fact, or from_
other causes, that led to their abandonment in this country, —
we are unable to state with any certainty; but on the 23rd of ©
July, 1869, their death-warrant was signed, so far as this 4
country is concerned, by the issue of an advertisement by
Her Majesty’s Commissioners for the Exhibition of 1851, -
wherein the public was informed ‘‘that the first of a series”
of Annual International Exhibitions, of seleéted works of
fine and industrial Art,” would be opened in London, at
South Kensington, on Monday, the 1st of May, 1871. It

Ye

Ppue undoubted success which attended the two great —

1874.] Annual International Exhibitions. 333

was then contemplated that these Annual Exhibitions should
be devoted each to certain classes only of industry and fine
art, and it was so arranged that within a cycle of seven
years all the principal arts and manufactures of the world
would have been illustrated in them.

Before entering farther into an account of those Exhibi-
tions that have hitherto been held, it is right that we should
state that, prior to the issue of the advertisement above
referred to, the whole question of Annual International
Exhibitions was fairly laid before the leading representatives
of Trade in London, and their opinions were invited as to
the probable success of such Exhibitions. We are informed
by one of the gentlemen so consulted that the unanimous
verdict of the London Trade was that such Exhibitions not
only could not succeed, but that they would be mere super-
fluities; that similar exhibitions, only on a far more exten-
sive scale than could be achieved at South Kensington in
the manner proposed, already existed, and were perennial, in
all the leading thoroughfares of London; and that a person
wishing to become acquainted with any particular branch of
manufacture could do so, far more successfully and speedily,
by visiting the show-rooms of a West End tradesman than
by an inspection of anything that his branch of trade col-
lectively would be likely to exhibit.

Anyone who has-been a studious visitor to the Annual
Exhibitions already held will be able to bear out completely
the views expressed above. ‘These Exhibitions have clearly
not commended themselves to manufacturers generally in
this country, whilst foreign nations have certainly been but
very imperfectly represented on every occasion, although
perhaps some exception may be made as regards the French
Annexe, but then, as must have been apparent to all, the
French Exhibition has not generally been devoted to the
special classes of objects for which each year’s exhibition
was supposed to be devoted. But, independently of this.
the French Annexe has, in a great measure, been the means
of bringing these Annual Exhibitions to an untimely end.
By this remark we do not mean to imply that there was
anything in the principle or manner of conducting these
Exhibitions that rendered their continuance even desirable ;
on the contrary, we were from the first impressed with a
conviction that their ultimate failure was inevitable, but we
were, perhaps, hardly prepared for their meeting with so
speedy a dissolution. It appears that the French Govern-
ment was induced to go to the expense of erecting its own
Annexe at South Kensington, upon the distin¢ét understanding

VOL. IV. (N.S.) 2.0

334 Annual International Exhibitions. (July,

that the exhibitors therein should be permitted to sell their
goods, thus converting that part of the Exhibition into a
bazaar or shop, whilst in other parts the exhibitors were
often prohibited from even putting a person in charge of
their several exhibits. From the reports on the 1871 Exhi-
bition, published in Paris, we learn that in that year the
articles sold in the French Annexe during the Exhibition
were valued at over £20,000. This proceeding on the part
of the Commissioners had, of course, the effect of handi-
capping all other exhibitors besides the French, which raised
a storm of indignation, especially amongst the English exhi-
bitors, which the Commissioners were unable to withstand ;
indeed many manufacturers positively refused to exhibit any
further unless the odious distinétion were withdrawn, and
that either all or none in the Exhibition should be allowed
to convert their stalls into shops. In consequence of the
firm stand made by the English trade representatives an
attempt was made to prohibit the selling license to the
French exhibitors, and the consequence of this was that the
French Court was not opened at all last year. This year it
is again accessible to the public, and purchases may be made
as freely as ever; for notwithstanding the prohibition
against the removal of goods until after the close of the
Exhibition, we are aware of one instance, at least, in which
the delivery of goods purchased in thesFrench Court has
already been effected.

The inevitable consequence of this course of proceeding
on the part of the Commissioners must, under any circum-
stances, have led to the early collapse of these Annual
Exhibitions; but we understand that, besides this, other
influences have made themselves felt which have induced
the Commissioners to declare that this year’s Exhibition
shall be the last. The faét is, we believe, that these Exhi-
bitions are not attractive enough to the public, and the
necessary consequence is that they do not pay. In other
words, these Exhibitions are not popular, and no better
proof could be desired of the indubitable fact that they are
not only not required, but that they are evidently looked
upon as unnecessary amusements for the London public.

Looking upon these Exhibitions as Institutions for the
Advancement of Knowledge, we think that the small at-
tractiveness which they present to the general public is a
sufficient condemnation of them from that point of view.
As places of amusement they fail, because the London
public is sufficiently educated to know how to discern _be-

tween what is excellent and what is worthless. As Indus-_

1874.] Annual International Exhibitions. 335

trial Exhibitions these annual institutions have lost their
hold on the public faith, and they have come to be looked
upon more as bazaars than as International Exhibitions in
the highest sense. Looking at these Exhibitions from a
‘South Kensington” point of view,—that is, as media of
instruction to the public,—we believe that they might be
made to pay, but then an entirely different arrangement to
the present must be made for that purpose. Instead of
inviting manufacturers to exhibit their goods at their own
cost,—which can but end in an imperfect representation
after all,—three or four manufa¢tories might be exhibited in
their most entire completeness, and visitors should be
allowed to purchase and carry away any articles they may
have seen manufactured. In order to carry out such a pro-
gramme the manufacture must be complete in all its details ;
but for the laying down of the necessary plant and ma-
chinery the Commissioners would, of course, have in the
first instance to bear all expenses, and perhaps even pay
people to set up their factories within the Exhibition; but
in all cases the manufactory should be complete, and the
Exhibition should not only consist of a display of manufac-
tured articles. With what interest would the blowing of a
retort of Bessemer steel be viewed by the fair inhabitants
of South Kensington,—at a safe distance from the sparks,
and viewed of course through a spec¢troscope,—and with
what delight would the young men of London hasten to see
a huge casting run direct from the cupola, or a massive bloom
of iron writhing under the thud strokes of a 50-ton steam-
hammer? We were fortunate enough to see some of the
glass manufactured for the Exhibition of 1851, and can tes-
tify to the attraction which such a display would yield to the
London public; whilst the manipulation of glass in its finer
forms—such as in the manufacture of wine-glasses, decan-
ters, or tumblers, and the subsequent processes of their
cutting and ornamentation—would contribute no slight en-
tertainment to the sight-seeing people of London. We are
perfectly well aware that these sights are all to be seen
within the great city of London itself, but they are not so
accessible to the general public as the display of the manu-
factured articles themselves. The only question for the
Commissioners to consider is whether such displays could
safely be carried out on the present site. The public have
now had over twenty years of exhibitions of manufactured
articles, and it appears that the time has now abundantly
arrived when the process of manufacture should also be
exhibited more fully than has hitherto been attempted.

336 Annual International Exhibitions. (July,

We refrain from entering into any further details on this
subject on the present occasion, but having thrown out the
idea in a somewhat vague way, perhaps, we proceed now to
review, as briefly as possible, what have been the results of
the past four Annual Exhibitions, including, of course, the
current one which has not yet closed its doors upon the un-
appreciating public.

The Exhibition of 1871 was confined mainly to three
classes, viz., fine arts, pottery, and woollen and worsted
fabrics, together with machinery employed in the manufac-
ture of the two latter classes. Besides these, however,
there were also exhibited educational appliances and instru-
ments, scientific inventions and new discoveries, and °
horticulture. Amongst the machinery employed in the
manufacture of pottery there were brick- and tile-making
machines, clay-crushers, pug-mills, pottery wheels, pipe-
making machines, stone-breaking machines, whilst in
another part of the building was exhibited every conceivable
variety of finished products of the potter’s art, from the
exquisitely finished designs of Wedgwood, Minton, and
Daniell, to a ginger-beer bottle and tobacco-pipe. Amongst
the machinery for woollen and worsted manufacture were
exhibited various power looms, combing machines, balling
machines, carpet-weaving machines, &c., &c., whilst the
manufactured articles were also exhibited in endless variety.
It would be out of place, upon the present occasion, to enter
into detail regarding what was exhibited so far back as 1871,
but it may be generally remarked that, whilst some of the
exhibits were decidedly novel, many were of an uncertain
age, and the Exhibition generally could not be looked upon
as in any way representing the fullest advancement that had
been developed in the special classes exhibited. Scientific
inventions represented upon that occasion formed the sub-
je@t of an article in the “‘ Quarterly Journal of Science” in
the same year.

The second of the series of annual International Exhibi-
tions was opened on the 1st of May, 1872. As in the former
year, this Exhibition consisted of three main divisions, viz.,
fine arts, manufactures, and recent scientific inventions and
new discoveries. The leading manufactures represented on
this occasion were cotton, cotton fabrics, jewellery, paper,
stationery, and printing, whilst musical instruments of all
kinds, and acoustic apparatus, were also represented.
Paper formed the principal topic of exhibition, and it was
dealt with at some length, at the time, in a special separate
article. Notwithstanding the great importance of the

1874.] Annual International Exhibitions. 337

classes selected for exhibition, it cannot be said that they
were well represented so far as the mechanical part of the
Exhibition was concerned, although there was a fair display
of manufactured goods. As regards scientific exhibits more
care was displayed by the Commissioners in the selection of
objects, so that fewer trivial articles found their way in than
was the case in 1871.

Class II. in the Exhibition of 1873 comprised silk and
velvet fabrics, steel and cutlery, surgical instruments,
carriages not connected with either railways or tramways,
substances used as food, and, finally, cooking and its science.
One noticeable feature in this Exhibition was a falling off in
the machinery department, which may perhaps be partially
explained by the existence of a formidable rival at Vienna,
where, it may be presumed, most articles worthy of being
exhibited were sent, in preference to South Kensington.
This year the industrial arts represented at South Kensington
include leather, hand- and machine-made lace, civil engineer-
ing, architectural and building contrivances, sanitary appa-
ratus and constructions, cement and plaster work, heating
by all methods and kinds of fuel, bookbinding, and foreign
wines. The mechanical exhibits are—machinery for lace,
leather, bookbinding, civil engineering and building, and
such as are included under the head of recent Scientific
Inventions.

At best, the present Exhibition cannot be said to be in
any way an improvement upon its predecessors ; in some of
the classes it is very poorly represented, and upon the whole
it decidedly lacks interest. Indeed, a visit to South Ken-
sington is quite sufficient to prove, to the most casual ob-
server, that these annual exhibitions are gradually dying
out from natural causes.

The great International Exhibitions have grown at so
rapid a rate that it is very clear that they could not long be
continued, upon their original basis, in consequence of the
vastness of the buildings required for their reception. But
in endeavouring to limit their proportions by spreading them
over seven years, their interest has also diminished in pro-
portion, not only to the visitor, but equally so to the exhibitor,
and hence the cause of their failure. In a recent letter to the
“Times” newspaper (Tuesday, June g), Dr. Forbes Watson
entered in some length upon the great question of Exhi-
bitions, and, while admitting the failure of the present
organisation, he recommends that instead of endeavouring
to make them popular, class exhibitions should continue to
be held, under a revised system of arrangement and manage-

338 Annual International Exhibitions. (July,

ment, more in the interests of respective trades than of an
unsympathising public. With regard to the present system
he argues that the ‘‘conditions under which they occur, the
brevity of their existence, the multiplicity of similar objeéts,
the impossibility of a systematic arrangement, make it all
but impossible that any profit should be derived from them
except to those already acquainted with the subject. Inter-
national Exhibitions,” he goes on to state, ‘‘ might be
utilised less for the purpose of increasing the number of
people possessed of technical education, than for raising the
level of knowledge among the classes already possessed of
the fullest information regarding each of the subjects repre-
sented at the Exhibition.” And this information once ac-
quired should, it is furthersuggested, be rendered permanently
available to the country by being embodied in museums.

Theoretically, this suggestion looks very well upon paper,
but practically we very much doubt the possibility of its being
carried out. The true advancement of manufacturing in-
dustry will, we confidently predict, never be demonstrated
in such exhibitions, for in most trades there are so many
secrets—each manufacturer possessing certain knowledge
of his art which is not patented or otherwise divulged to his
competitors in trade—that it is impossible to hope that the
ultimate stage of advancement and knowledge will ever be
represented in public exhibitions. Indeed, it is to these ex-
hibitions chiefly that we owe the vast amount of foreign
competition in manufactures, not only abroad, but even in
our own markets.

Whatever may be the next stage of International Exhi-
bitions, it is to be hoped that a reasonable time will be per-
mitted to elapse before anything else of the kind is at-
tempted ; indeed, it seems necessary that such should be
the case, for, the present annual series having come to a
premature end, a fresh system and organisation will neces-
sarily be required before anything new can be attempted.

1874.] ( 339 )

VI. THE IOWA AND ILLINOIS TORNADO
oF May 22, 1873.

By JAMES MAckKINTOSH, M.A.

trees, buildings, &c.—be traced further back than

Section 35, Warren Township, Keokuk Co., Iowa.
At the point where the destruction commenced, the South
Skunk river bends southward, and then again to the east,
thus half inclosing a low level area of about 1 mile in length
by 3a mile in breadth. ‘This bottom land is surrounded by
bluffs about 70 feet in height on nearly all sides, the river
flowing close to the bluff on the S.W. It was at the north-
east edge of this natural amphitheatre that the tornado first
attained force sufficient to demolish fences. It is difficult
and unnecessary to determine its starting-point: there is,
however, no doubt of the fact that it first attained to deso-
lating violence on the farm of W. W. Morrow, situated
half-way up the bluff. Its previous history was only that of
a thunderstorm, accompanied, perhaps, by an unusual
tumult and whirling of the clouds. In tracing its develop-
ment and progress, therefore, I probably labour under no
disadvantages which do not necessarily attach to the history
of all such meteors, except those arising from the circum-
stance that the tornado was not at any point of its progress
witnessed by a skilful meteorologist.

Mr. Morrow testified that neither he nor any of his people
noticed any funnel-shaped appearance or tongue of cloud
approaching the earth. There was a strong wind for a
minute, but the destructive gust appeared to be instanta-
neous. A smart shower of hail followed the gust. A
whirling of the clouds was observed several minutes before
the wind. A little lightning was seen. The storm travelled
E.N.E. over Andrew Surber’s farm, blowing down fences
with a S.W. wind. He saw the clouds whirling lke a great
wheel, 35 degrees in width, before the storm, but did not
notice any funnel appearance. Some hail fell with the
wind, and a considerable shower of rain after it.

John Malcum, Section 30, Lancaster Township, was
I mile south of tornado when it occurred. Heard a roaring
like steady thunder in the west about a quarter of an hour
before the storm came. Saw no lightning. A cloud covered
the western, the northern, and north-eastern portion of the
sky. It extended somewhat beyond the zenith. The rest

‘a tornado could not—by its destru¢tive effects upon

340 The Iowa and Illinois Tornado. (July,

of the sky was clear. Saw a mass of clouds whirling
contrary to the hands of a watch. The whirling mass
appeared to be about 60 degrees high when dire¢tly opposite.
A smart shower fell some time after the tornado.

On Malcum’s farm the roof of a stable was blown to the
south-east. This was the first damage done by a north-west
wind. ‘Two hundred yards south of the stable a fence was
blown toward the north-west and north. The storm, after
becoming destructive, had travelled 14 miles before it
developed force sufficient to commit destruction by a north-
west and south-east wind.

The breadth of fences thrown down on the farm of
T. Dawson, Section 31, Lancaster Township, was about
60 rods. The outhouses, &c., were damaged. A cultivator
weighing about 200 lbs. was carried or dragged 30 feet ; it
presented to the wind a surface of not more than 3 square
feet. If it was carried, the lifting force of the wind must
have been between 60 and 70 lbs. per square foot. The
ground showed no signs of its having been dragged.

M. Williams, lawyer, Section 32, Lancaster Township.
watched the storm as it approached for about one hour; it
was afew minutes after 2 P.M. A cloud rose in the west,
which, stretching to the north-west, presented the appear-
ance of heavy rain. Previous to the approach of this cloud
the sky was nearly clear. The wind during the day was
southerly. About twenty-five minutes after the tornado the
wind was again from the south-west. The storm-cloud did
not extend far past the zenith to the south. Saw the funnel
distin@tly. It alternately lengthened and contracted, rose
and fell. When it contracted, it appeared as if the narrow
point next the earth was cut off, leaving the lower end
broader. At times the upper end appeared to reach the
overhanging clouds, and at times to be not so high. It
was of a dark blue colour when 250 yards distant; when
300 yards distant it subtended an angle of about 75°; the
angle subtended by the top of it at that distance was about
55- It had a zigzag motion. Half an hour previous to the
tornado there was incessant lightning in the north-west.
Heard no thunder. There was no lightning in the tornado.
A little rain and hail fell just before the tornado, and a
smart rain-shower about twenty minutes after it. Heard
that to the northward there was a terrific storm of rain and
hail, accompanied with thunder and lightning. The wind
was south generally during the day. As the tornado ap-
proached the wind changed to a little east of south. Saw
the dark funnel strike the ground on my farm. Saw it
whirling contrary to the hands of a watch. This witness

1874.] The Iowa and Illinois Tornado. 341

was stationed about 25 yards south of the storm-centre
when nearest to it. The fences were generally thrown
toward the centre on either side, but where the dark cloud
touched they were carried away for a space 60 yards wide.
We have here the first evidence of the dark cloud touching
the earth in perfect funnel-form ; but its touch is yet only
temporary: it proceeds with a wavy, zigzag, circular-
pendulum motion. By-and-bye its tread will make the earth
tremble.

The storm traversed Jones’s farm, throwing down fences,
until it struck the Wolfden school-house, which lay near
its centre. The school was in session when the tornado
struck it.

Richard Weller, teacher, testified that this occurred at
2.15 P.M. precisely. This time is valuable, and I have
adopted it as one of the data for calculating the velocity of
the storm. The school-house was moved, with the children
and teacher in it, to the east, the north end 30 feet, the
south end 20 feet. It was not overturned. The windows,
roof, &c., were much damaged, but there were no evidences
of explosive forces. The weight of the building was given
by Mr. Williams as probably 30,000 lbs. The surface ex-
posed was 360 square feet, besides the slanting roof. The
slant of the roof was about 45°. The foundation was stone.
It became very dark as the tornado struck. After leaving
the school-house, which is situated in a slight ravine-like
depression, the fury of the tornado abated somewhat : hence,
although it was nearly central over the hamlet of Hayes-
ville, the frail houses were scarcely touched.

The storm up to this point had been travelling E.N.E.
Since leaving South Skunk river it had been traversing a
rolling prairie, with numerous sloughs, as they are called,
but nothing like a water-course. It struck Troublesome
Creek, the banks of which are well wooded. No sooner did
it do so than it increased greatly in power, changed its path
temporarily to due east, and developed the phenomena of
two or more funnels or branches of a funnel. Down in the
hollow, among the trees, stood the house of widow Jacobs.
It was completely demolished, but without signs of explo-
sion. The storm-traces are already in great part obliterated,
and a new house rebuilt. The path of destruction was
200 yards wide at this point, and the general aspect of the
fallen trees within this limit presented all the appearances
of a complete cyclone revolving contrary to the hands of a
watch, although nothing particularly worthy of notice pre-
sented itself. About a quarter of a mile from the main

VOL. IV. (N.S.) 2x

342 The Iowa and Illinois Tornado. [July,

track to the south, a swath, about 50 yards wide, was cut
through the fences by a south-west wind. This swath ap-
peared to curve towards the main storm-path, but it was not
possible to follow it until it reached it, because of the
sparseness of the fences, and because there had everywhere
on that side of the storm been a strong south-west wind, and
this swath was merely exceptionally strong.

The storm-centre next traversed the Grout Farm, now
occupied by Samuel Brunt, and passed about 100 yards to
the north of the village of Lancaster. Here its operations
became more interesting.

Samuel Brunt heard it roaring a long time before it
arrived; as. it approached saw two funnels distinétly: their
summits were lost in the overhanging mass of dark cloud.
Saw funnel on the south side, which was the smaller, swing
around in a half-circle and join the larger one. The funnel
had a pendulum motion. When it struck the ground it
seemed to smoke, the smoke surging up like spray upon a
wave-beaten rock. The wind felt cold as it passed. Saw
lightning during tornado. The breadth of the dark apex of
the main tornado, where it touched the ground, appeared to
be about roo feet; there the wheat was mown as with a
scythe.

Tlte breadth of the part of the storm of sufficient power
to throw down fences was here 200 yards. The fences on
the north side were blown south, those on the south side
north, while along the centre everything was carried east
with the storm. An apple tree, 7 inches in diameter, which
had stood on the north side of the centre, was carried first
14 yards south, with a little westing, then round in a regular
curve 24 yards toward due east, and then due east for
70 yards. A beam, 2 ins. X 4 ins. x 14 feet., and weighing
25 lbs., was driven into the ground 3 feet g inches at an
angle of 35°, after having been carried 35 yards from the
barn roof. The following is a sketch of the path of the
apple tree: it stood at a, and was carried to 0.

Fic. 8.

1874.] The Iowa and Illinois Tornado. 343

Fred. Tollman, Lancaster Village, was within the edge or
the tornado. Was whirled like a top for 50 yards, and
lodged against a fence. Observed it for more than fifteen
minutes before it came. Saw trees twisting in the grove
half a mile distant. Saw the funnel whirling contrary to
the sun ; its summit was lost in overhanging cloud. Thinks
the upper cloud was also whirling. Saw only one funnel.
Saw lightning flash up and down the funnel. Saw a tree
thrown out from the top of the funnel about 1 foot in
diameter. Top of funnel 60 degrees high when 70 yards off.
There were two funnels with the small ends together, thus,
the upper one being the largest :—

FIG. 9.

The evidence for the village of Lancaster is somewhat
discordant, or rather various. Some saw only one funnel;
some two funnels, side by side; and others two funnels
superimposed, with the small ends together. The discre-
pancies are, however, easily accounted for. As the cloud
approached it grew very dark. The tornado doubtless
changed its form rapidly. The observers took a glimpse at
it, and ran to attend to their houses, or had to watch it
under difficulties. Those who saw two funnels appear to
have seen through the centre of what appeared to those at a
greater distance as only one funnel with the larger end
down. The evidence afforded by the ruins in the path of
the storm gives no support whatever to the belief that there
were two distinct whirlwinds. The two dark clouds touching
the ground worked together in the strictest harmony in pro-
ducing such effects as would be produced by one tornado

344 The Iowa and Illinois Tornado. [July,

whirling contrary to the hands of a watch. But, as already
instanced, streaks of wind of unusual power curved in half-
circles toward the centre at certain places. One of those
streaks passed in a north-easterly direction through the
town of Lancaster, while the main whirl was 100 yards to
the north of it. This streak was at first only a few yards
broad, but rapidly increased in width as it proceeded. It
first unroofed a frail stable, without injuring the house
beside it. It then increased in force, throwing down four or
five houses, and unroofing as many more. The following
shows the position of the houses and the directions in which
they were blown :—

FIG. Io.

The long arrow denotes the main track; the curved arrow
the streak mentioned; the short arrows show the direction
of the destruGtive wind which threw down the various
buildings. Between the building a and the main storm-path
there is a space of 50 yards comparatively uninjured. The
sketch does not pretend to be strictly accurate as to dis-
tances, but to give the relative positions of the houses.
Leaving Lancaster, the whirlwind travelled down the
declivity toward North Skunk river in a direction somewhat
east of north-east. It levelled the fences in its path, in the
way already described, and which never varied from its
commencement to its end. The house of widow Dogget,
situated about a quarter of a mile south of the river, stands
a little to the north-west of the storm-centre, at the com-
mencement of the level bottom lands. Here two deep
ravines—one from the south and one from the east—meet.
Here the storm developed enormous power, smashing up the
timber terribly. The roofs of the house and barn were
carried south and somewhat west. ‘The trees on the north
side of the centre were thrown down toward the centre,
some pointing south-west and south, but the majority south-
east. On the south side of the centre they lay pointing
north-east, north, and north-west. An oak tree, 12 feet in
circumference at the base, was broken across 12 feet from
the ground. At the bottom of the narrow, steep ravine,

1874.] The Iowa and Illinois Tornado. 345

running east and west, trees were lying just as they fell,
some pointing east and some west.

One quarter of a mile beyond Mrs. Dogget’s house the
tornado reached North Skunk river, which it then followed
for over 2 miles, in a south-easterly direction, until it came
to the southerly bend of the river, opposite Kohlhaus’s
saw-mill, when it suddenly turned to the north-east. The
bottom lands on both sides of the river are here covered
with tall timber, and through this timber the storm tore its
way with resistless fury. All trees within a breadth of about
roo yards were either overturned or broken off and barked.
The barking was evidently the result of three things :—

1. Many of the trees barked had been bent, so as to loosen
the fibres of the wood. Such bending would infallibly
loosen, and perhaps break, the bark.

2. The air was thick with missiles, which not only broke
the bark, but sometimes penetrated the wood. I have
seen a corn stump less than 2 inches in length
sticking in the bark of a large tree which it had
penetrated.

3. The peeling off of such loosened and broken bark
would be a light task for such a tremendous blast.
There was not the slightest evidence of electric action
or of vapour explosion.

Broken trees had the bark torn off, both up and down,
from the point of breakage. Trees half broken and bent to
the ground were similarly stripped.

At the place of rupture the trees generally presented that
broom appearance in which the supporters of the theory
that electricity is the principal agent in the production of
tornadoes have seen conclusive evidence of its truth. It
will afterwards be shown, when this phenomenon becomes
more common than could be expe¢ted on the soft soil bor-
dering North Skunk river, where trees were more easily
uprooted than broken, that this broom appearance is due to
the excessive bending and straining of the fibres of the
wood, and their rupture, in succession, from the exterior
inwards.

The river, being impassable, rendered the examination of
the general position of the fallen trees more difficult.
Everything, however, corroborated the evidence already so
abundantly adduced, that the tornado was a whirlwind of
powerful centripetal tendency, circling contrary to the hands
of awatch. The following arrangement of fallen trees was
selected as being typical. It was found on the north side of
the river, near the centre of the tornado.

346 The Iowa and Illinois Tornado. (July,

No.1 is a tree 3 feet in diameter, but much decayed,
blown down from the E.S.E. No. 2 is a tree 3 foot in
diameter, blown down S.S.E. No. 3 is a tree 2 feet in
diameter, blown down from the W. No. 3 lies above No. 2,
and No. 2 above No. 1. It occurred just where the storm
left the river.

Fiac. 11.

That the force of the storm was enormously increased
immediately after reaching North Skunk river is proved by
the greatly extended width of its path. At A. Dogget’s and
B. C. Moore’s houses, three-quarters of a mile distant from
the storm-centre, the out-buildings were damaged and the
fences thrown down by a southerly wind. Mr. Dogget tes-
tified that the tornado appeared somewhat like two funnels
with the smaller ends together, and that when apparently
33 miles distant the column subtended an angle of about 25°.
The houses of these gentlemen are situated on the summit
of the bluffs facing the river, which are perhaps 200 feet
high.

The house of Joseph Ash, situated on the face of the
bluff, and distant from the river about half a mile, was blown
to the S.S.W. Large trees were at this distance blown down
in the ravines running to the river. Mr. Ash testified that
the wind lasted a few minutes, and that it changed to the
north-west after the passage of the tornado. A little hail
fell before the storm, and a small .shower of rain after it.
Saw lightning and heard thunder. It grew cool as the
storm passed. ;

1874.] The Iowa and Illinois Tornado. 347

The following represents the apparent direCtion of motion
of the two funnels as they approached each other :—

PIGS 12°
&
7

The house and steam saw-mill of Joseph Kohlhaus stood
directly in the path of the meteor, at the distance of a
quarter of a mile from the river, on the north side.

The buildings stood upon the summit of a rising ground,
about 30 feet high. Between it and the river is a half pool,
half marsh. It was completely emptied of water. The
breadth of the path of wholesale destru€tion was, upon the
summit of the hill, 270 yards. The house stood 100 yards
from the eastern and 170 yards from the western extremity
of this path. The timbers and contents of this house were
carried in a half-circle first to the north-west, then to the
west, then south-west, then south, and finally to the north-
east, the heavier articles being generally sifted out first,
thus marking the way the ruins went.

On the eastern edge of the path was an orchard, and on
the western a wood. The trees in the orchard were blown
down from the south-east and south; the trees in the wood
from the north and north-west. Portions of the clothing
from the house and shingles from the roof lay among the
trees in the wood, or stuck among the branches. ‘There
were no signs of explosion, the doors and windows having
been blown in. The inmates were all more or less injured.
The width over which fences were blown down was here
about three-quarters of a mile. An iron plough, weighing
200 lbs., was carried 4o yards. The sheet-iron chimney was
carried 2 miles to the north-east. An iron sausage-machine,
6 inches by 8, and weighing 15 lbs., was blown away; part
of it was found 1200 yards distant. The wheels of waggons
were smashed, and the tyres twisted.

Fig. 13 is a representation of the effects of the whirlwind
at this place.

After leaving the mill the storm ascended a hill some
200 feet in height, levelling the fences, but with evidently
diminished violence.

Passing over the top of the hill in a north-east direCtion,
it struck Rock Creek, which here runs south, with a little

348 The Iowa and Illinois Tornado. [July, ©

easting. Immediately altering its course, it went straight
up the creek for about half a mile, developing prodigious
power. The large trees which lined the banks were torn
and peeled and overthrown in promiscuous ruin. Ata point

Fic. 13.

where there is a small circular island, and a considerable
amount of stagnant water around, the storm would appear
to have stood still for a moment. Fig. 14. shows the
position of the fallen trees at this point.

There were no trees on the island itself. There was no
evidence whatsoever that the barking of the trees had been
effected by electrical action or sudden evaporation. Every-
thing tended to prove that the bark had been loosened and

Fic. 14.

Yn
ae
\"
Ssy/

broken by the excessive bending of the trees and by flying
missiles. One of the steers killed at this creek had an oak
rail driven completely through its shoulders. ;

A

1874.] The Iowa and Illinois Tornado. 349

On reaching a slough which enters Rock Creek from the
north-east the tornado followed it. Beside this slough and
close tu the creek was a small grove of young trees belong-
ing to John Stein. This grove was completely carried
away, nothing remaining except a few barkless twigs. At
no point in its course did the storm develop greater energy
than at this grove. Generally young saplings, over which
the centre of the storm passed, were, although stripped of
bark and twigs, left standing. Here the ground was whipped
as bare as though the grove had beeri lashed with a whirl-
wind of fire. The tornado then passed between the houses
of William Goeldern and John Stein, sweeping the fields,
within the narrow path of its greatest violence, clean of
grass, wheat, and corn stumps, while the ground was torn
and furrowed by flying rails andtrees. Therails and broken
timber had been gathered from the fields; but John Stein
assured me that they lay thickest along the centre of the
storm. Along the sides of the path of greatest violence
many rails were driven deeply into the soil, end foremost.

While the main whirlwind thus pursued the path de-
scribed, there were smaller off-shoots or arms which played
havoc on its south-east side. Such an arm cut a swath
about 12 yards through Schild’s orchard from south-west to
north-east, the swath widening as it went. It was not
possible to trace it until it reached the main storm, for
reasons similar to those already given. It seems probable,
however, that it joined it at the little island above mentioned,
where the storm appears to have momentarily stood still.
The relative positions favour such a surmise. This streak
of strong south-west wind was a quarter of a mile distant
from the centre of the main tornado.

A similar streak levelled the fences close to the house of
John Stein for a width of 50 yards, while nearer the main
tornado the fences remained standing. This streak, I sur-
mise, joined the main storm at the grove above mentioned.
A similar arm tore down the new barn of F. A. Latz, about
a quarter of a mile farther on, without injuring weaker
buildings close beside it. The path of this streak is said to
have been very distinct among the fences until it joined the
whirlwind near the house of Peter Marsh. ‘The fences were,
however, already restored.

George Star, three quarters of a mile south-east of the
tornado, said that about I P.M., it commenced to thunder
and lightning in the north-west. The storm advanced along
the northern sky, and it lightened terribly there previously
to the arrival of the tornado. A big cloud extended from

VOL. IV. (N.S.) 2

350 The Iowa and Illinois Tornado. (July,

south-west to north-east. It cleared up immediately after
the tornado, both here and in the north. ‘This witness lost
eighteen head of cattle at Rock Creek. One was perforated
by a rail.

John Marsh’s house stood a little to the north-west of the
centre of the storm. He watched it as it came direCtly
toward him. It deflected a little from side to side, with a
zig-zag motion. It turned and twisted like a screw in
revolution. All the family were in the house, the house
having no cellar. It became as dark as midnight. The
windows and doors were blown in, in spite of resistance, and
they knew no more until they found themselves lying in the
slough, severely wounded.

The destruction at this house was most complete. The
house was carried forward from its foundations bodily; but as
it was going downa declivity toward a slough, it failed to strike
the ground until it went to pieces. The heaviest timbers
and the inhabitants were deposited in a slough, about 100
yards S.S.W. of where the house stood. One child was
killed instantly, and Mrs. Marsh has since died. The frag-
ments of the house were carried, first to the south-west, then
in a curve to the south, the south-east, the east, and then
along the centre of the storm to the north-east, the heavier
articles sifting out as they went. I found ears of corn
200 yards to the south-west and south of the house, and a
fragment of heavy wood 400 yards to $.S.W. Two cows
and thirteen hogs were ina yard a little nearer the centre
of the storm than the house. They were carried 100 yards
to the south-east, and killed or fatally injured. A stone
from the foundations of the house, weighing about roo lbs.,
was said to have been carried about 100 yards south; but
I could not find it. Sowing machine, cultivators, wagons,
&c., were wholly carried away, and left not a wrack behind.
The timber was generally reduced to the dimensions of fine
fire-wood, and thickly strewn along the path of the storm
to the north-east. The width over which fences were thrown
down was here about half a mile.

Fig. 15 is a sketch of the path of the ruins of Marsh’s
house, aaa representing track of ruins of house, } 6 the
centre of path.

A quarter of a mile to the north of Marsh’s house stood
the house, barn, &c., of M. Fuh. They were blown to the
south-west, but without being carried away. The next house
struck was that of M. E. Hamis, the storm-centre passing
about 20 yards to the north-west of it. The fiercest of the
storm was here only 100 yards wide, but fences were blown

1874.| The Iowa and Illinois Tornado. 351

down for over 500 yards. The doors and windows of the
house were driven in by the wind and the flying missiles,
and immediately the house went to pieces. The house and
out-houses were carried away, broken to small pieces, and
deposited fora mile or two along the path of the storm.
The trees around the house, which were not plucked out by
the roots, had their tops and branches broken off and their
bark stripped from them. The stripping of the bark was

Fig. 15

evidently due to the causes already assigned. The stripping
was most complete on the south-west side of the trees. A
fence 400 yards in length, and running east and west, was
deprived of its boards, the posts still remaining in the
ground. Where the storm-centre crossed it, the dire¢tion
toward which the posts were leaning was intermediate. On
the west of the centre the posts were leaning south, with a
little easting, and on the east of the storm-centre they were
leaning north, with a little westing.

Fic. 16.

The above is something like the disposition of the posts
along the line of the fence. The length of the fence thrown

352 The Iowa and Illinois Tornado. (July,

down east of the centre was about one-quarter greater than
that thrown down on the west of it.

The corn-stalks in a contiguous corn-field were thus dis-
posed :—Those on the south-east side of the centre curved
around from pointing nearly due north to nearly due west.
Those on the north-west side curved around from pointing
nearly due south to nearly due east. Along the centre all
pointed with the storm. This shows the direction of the
last wind, strong enough to alter the position of the stalks.
(See Fig. 17).

Matthias Linen, a quarter of a mile north-west of the edge
of the storm, testified that it presented the appearance of a
great column, reaching from the ground to the clouds, and
whirling contrary to the sun. It seemed to remain almost
still at some places, and then would dart forward. Hail
4 inches in diameter, very irregular in form, fell as the storm
passed.

Paul Piffer, Clear Creek Township, Section 9, testified
that the tornado looked like a big tree, only it was five times
greater at the top than the bottom. It turned like a wheel
in a mill. Its direction of evolution was against the hands
of a watch. At the distance of a mile, its top, when it
entered the cloud, made an angle of about 60°. Hail as
large as pigeon’s eggs fell before the storm, and it rained
very hard after it. Saw lightning in the west previously.

Mr. Piffer’s house stands about 70 yards to the north-
west of the storm-centre. Its path is here about 200 yards
wide. The arrangement of stalks in a corn-field was the
same as that already given. The roof of the house was
carried south. A stump-cutter, which was standing by the
house, was carried—the iron portion 50 yards south, the
wooden portion half a mile to E.S.E. Wheels which came

1874.] The Lowa and Illinois Tornado. 250

within the reach of the storm were dashed to pieces, and
the tyres twisted into all sorts of shapes. An oak tree,
3 inches in diameter, and which stood exactly in the storm-
centre, was split by a fragment of a board 1 inch thick.

The board was originally probably 6 inches broad and
8 feet long. Of the two small fragments remaining in the
tree, the longer was only 17 inches in length. The board
was driven into the tree from the south-west. The path of
extreme violence, about fifty yards wide, was strongly marked
in the grove of young oaks. ‘They looked as if they had first
been lashed against a pile of stones and then trailed in the
mud. Portions of bark were struck off and the smaller
branches shattered and peeled. ‘This grove stands upon the
edge of a steep declivity about 100 feet in height, at the
bottom of which flows Clear Creek. Here is a circular
hollow nearly enclosed by high bluffs, and within it the
storm raged with demoniac fury, smashing trees of 4 feet
in diameter to pieces.

The following instance was found on the opposite declivity,
up which the storm raged with undiminished power :—

Fic. 18.

The tree stood at N originally. Its root was partly de-
cayed, and it must have fallen with the first strong gust.
The path which it travelled was cut out in the grass by
its root. This path was 47 yards in length, and was
nearly circular. It first moved to the north-west and then
round in a curve, until it lay pointing to the north-east,
with its top almost touching the spot where its root had
formerly been. The tree stood to the north-west of the
storm-centre, and was 2 feet in diameter.

Crossing the summit of the rising ground, which was
thoroughly ploughed up, the storm traversed a wooded ravine,

354 The Iowa and Illinois Tornado. (July,

where for a width of fifty yards it deprived the young trees
of their twigs and of much of their bark, besides throwing
down the full grown.

The house of Nick Engledinger, Section 10, Clear Creek
Township, stood about 100 yards from the south-east edge
of the tornado. From any indications which the remains
presented, the timbers must have first been carried north.
Two persons were killed—one of them being torn to pieces.

A hog weighing 400 lbs. was carried one mile and a
quarter in the line of the storm.

The house of Jacob Kcoerth stood fifty yards within the
north-west edge of the storm. The timbers went south.
The people tried to prevent the wind from blowing in the
doors and windows, and could not. The wind entered and
biew the house asunder, leaving the floor in its proper
position. Hogs weighing 300 lbs. were carried to the north-
east across a ravine and deposited 300 yards away. A horse,
a cow, and a bull were similarly carried 200 yards. Sheep
were carried 400 yards. In addition to the accidents in-
separable from such an aérial voyage, the bodies of the
animals were driven full of pieces of wood. On this ac-
count the bodies of all animals which perished in the storm
were burned.

A horse-power machine, partly wood, but chiefly iron, and
weighing 2400 lbs., was pushed or carried six yards. It
was resting on the ground, and was separate from all other
objects. There were no marks upon it arising from violent
collision with other bodies. It exposed a surface of about
2 square feet to the wind. It lay close tothe ground. ‘The
master of this house was absent, and information, owing to
the invalid condition of the inmates, hard to obtain.

The storm now turned somewhat more to the northward,
traversed several fields, demolishing the fences, until it
struck the house of R. F. Campbell, Lafayette Township,
on the borders of Clear Creek Township. The exact
position of this and the two immediately preceding houses
was difficult to determine upon the map, because of its very
defeCtive condition, and because their owners could not tell
me what section they were in.

The following is the appearance the vortex presented at
the distance of 70 yards. There appears to be two incipient
funnels, one on either side.

A post 8 feet in length, and driven into the soil 3} feet,
and 4 inches in diameter, was pulled out by the wind. It
stood without attachment.

The width of the storm here is 160 yards. The house

1874.] The Iowa and Illinois Tornado. 355

stood within 20 yards of the north-west edge. It was tilted
up on its corner bodily, inmates, floor, and all, and de-
posited on its roof 17 yards to the south-west of its former

position, and then went to pieces. There was no indication
of explosion. The accompanying is a plan of the effects
of the storm at this house :—

FIG. 20.

oh =

a is the house which was carried in the direction of the
arrow. 6 is a stable and c a haystack, both untouched.
-These were twenty yards from the house. d, e, and fare
portions of a fence which were thrown down. d and e
were thrown south, leaving the intervening portions un-
touched. f was thrown north. g is the post already
mentioned.

This was the last destruction in Keokuk county. The
tornado ceased to touch the earth on Mr. Campbell’s farm.
It drew itself up into the cloud from which it had come
down. Hitherto it had traversed a country full of deep and
well wooded ravines. Here it entered upon a flat, bare
country—in fact, a water-shed. It continues much the same
for the seven miles which the tornado here skipped.

356 The Iowa and Illinois Tornado. (July,

The storm having ceased to act as a tornado upon the
surface of the earth, I proceeded to Westchester, Washing-
ton county, where it was reported to have struck. There
can be no doubt, however, that a strong—though not a
destructive—wind was felt over the intervening space, and
that it obeyed the usual law of cyclones by blowing in
spirals toward the point over which clouds continued to
whirl like a great wheel.

Rev. J. P. Coffman, Cedar Township, Section 33, gave
the following evidence :—The tornado arrived about 3 P.M.
Heard the noise for more than one hour previously. When
it was hailing, heard the sound just as distinct as before.
Did not hear roaring after the storm passed. The wind
before the storm was nearly due south. After the storm,
and with the rain, the wind came from the north and north-
west. Have learned that 2 or 3 miles to the north the rain
was tremendous. There was lightning in the north-west
previous to the tornado. As it approached, saw light fog-
like clouds, rushing, with the greatest rapidity, from the
north. Its form was not so distinét before as after it passed,
when it presented a decided funnel appearance. It was
nearly clear in the south. When the funnel was distant
about I mile it appeared to subtend an angle of about 25.
The funnel might have entered the dark, overhanging clouds,
but it appeared to be wholly in view. There seemed at one
time as if there had been a violent explosion in the revolving
mass, as it was somewhat broken up. Hail larger than
pigeon’s eggs fell with the south wind before the storm.
After the tornado the wind came from the north-west, with
rain.

The tornado passed over Mr. Coffmann’s house, blowing
down fences about a quarter of a mile in width, and damaging
buildings. It was all done by a south-west wind.

The storm-centre passed right over the house of John

Maughlin, Cedar Township, Section 25. He testified that.

he saw a complete funnel form about 200 yards distant, and
that it went up into an overhanging mass of cloud. The
funnel was perfectly opaque, and left a fog behind it, so that
nothing could be seen for several moments after it passed.
At the distance of 200 yards it appeared to be only 15 degrees
in height. Saw no lightning.

The outhouses on this farm were badly damaged.
Fig. 21 shows the position of the ruins. The arrows point
in the direction toward which the buildings were blown
down. ‘The fences were blown toward the storm-centre;
those at the centre were carried away.

1874.] The Iowa and Illinois Tornado. 357

a
ae

al

Fic. 21.

Andrew McKee, Cedar Township, Section 30, said—The
clock, which had just been cleaned and regulated, was
thrown down and stopped at 3.10 P.M. Previous to the tor-
nado the lightning was warping incessantly like a snake
among the dark blue clouds in the north-west. Chunks of
ice, about x inch in diameter, fell previously to the tornado,
accompanied by a light east wind.

I myself saw the clock above mentioned. It still pointed
to 3.10 P.M. Mr. McKee’s house stands 50 yards within the
north-west limit of the storm-path. The buildings were
partly pushed, partly blown down toward the S.S.E. The
fences were blown to the south-east. A little empty house,
about 40 yards to the east, was blown to the south-east, and
some of it was carried clear across the path of the storm.

The hedges along the east and west roads are here filled
full of débris, such as corn stumps, &c. On the south-east
of the storm-centre the débris is driven into the hedge from
the south, and on the north-west side from the north, but
there is a greater extent of hedge with débris driven into it
from the south than from the north. The position of the
débris driven in from the north seems frequently to have been
subsequently affected by a west wind. ‘The hedges running
north and south have débris driven into them on the north of
the centre from the east and on the south of the centre from
the west, but the extent of hedge with débris driven into it
from the west is greater than that with débris driven into it
from the east. The hedges over which the storm passed
looked as if they had been whipped violently against a wall
and then trailed in the mud; they were smashed and par-
tially barked, and sometimes carried away. This description
applies to the hedges over which the whirlwind, at any part
of its course, passed.

VOL. IV. (N.S.) . Biz,

358 The Iowa and Illinois Tornado. (July,

George Gilchrist, Cedar Township, Setion 29 (house di-
rectly in the centre of the storm-track), testified that when
the storm struck the house Mrs. Gilchrist, a boy, and a child
were in front of the west door, trying to reach the cave, the
boy and child being a step or two in advance. The boy and
child were instantly carried several rods to the west, while
Mrs. Gilchrist was thrust back into the house. The house
immediately went bodily, going a little to the north of the
boy, who saw it go past like the railroad, as he expressed it.
Its sills struck the ground 40 yards from their former posi-
tion, and the house tumbled over and went to pieces, leaving
the inmates comparatively unhurt. As it went to pieces it
was struck by a west and south-west wind, the furniture
being carried far to the east and north-east. It grew dark
as midnight when the tornado struck.

Fic. 22.

Sketch of Effects of Storm at Gilchrist’s House. a shows the point at which the house was
struck, and 0 the position at which the house stood.

When the storm struck the house of William Caldwell,
Cedar Township, Section 29, the inmates were in the kitchen,
which was a separate building. The wind blew so hard as
to threaten to blow in the south door. Four strong men
placed themselves against it: the hinges and lock were
partly broken. These four men barely held the door with
their utmost strength until the house went in a body: the
men found themselves, together with the other inmates, a
few yards to the north, lying among débris ; the door was
found a quarter of a mile away. The door presented to the
wind an area of 18 square feet.

Mr. Caldwell’s house stood on the south-east edge of the
most violent vortex. It was first pushed 6 feet to the north-

1874.] The Iowa and Illinois Tornado. 359

west, ploughing up the ground. The resistance of the ground
and of tree roots here stopped it. It then turned up on its
edge, and was then lifted over the tops of trees 20 feet high,
without injuring them, and carried 100 feet to the north-east,
falling entire, and going to pieces as it fell. The house
stood with its end to the south; the area of this end was
280 square feet, or thereabout; the area of the floor of the
house was 480 square feet, or thereabout ; the weight of the
house could not have been less than 20 tons. The trees
over which the house was carried are young, and were pro-
bably so bent as to allow the house to rise at an angle
of 45°.

A heifer, weighing 700 lbs., was carried away by the wind,
and thrust head foremost into wet soil until her fore-
quarters were buried.

Fic. 23.

s

Sketch of Mr. Waters’s House. a, the Granary; b, the Cave; c,c, Trees uninjured ;
d, Trees hurled; e, Sill.

Thomas Waters, Jackson Township, Section 19, witness:
—Saw the tornado coming rolling on the ground like a wave.
Went to the cave, and called upon Mrs. Waters to follow ;
she would not. Stood in the mouth of the cave, which was
8 yards south from the house, and facing it, and saw the
house blown away: it was struck from the south-west.
First, a portion of the roof was blown off; then the house
went bodily like lightning. When the house had gone I
came out of the cave, and was blown to the E.S.E.

360 The Iowa and Illinois Tornado. (July,

Mr. Waters’s house was 30 x 16 x 11 feet without the roof.
It was carried, sill and all, 24 yards down a declivity without
being turned round or tilted over. When it struck the
ground, it at first merely shaved it with the foremost sill,
gradually going deeper until the resistance became so great
as to cause the house to turn over, when it went to pieces.
The ground was ploughed up about 2 feet at the deepest
point. The house had fallen 3 feet in travelling 24 yards,
Its weight was at least Io tons.

Between the cave—which was only about 4 feet above the
surface—and the house, but nearer the cave, stood a small
tree ; against it a spade was leaning. Mr. Waters testified
that it was not blown down. Two yards east of the tree
stood a bucket containing a small quantity of lime, and
weighing Io lbs.: it was not disturbed. To the south-west
of the cave the trees (c, c) were comparatively uninjured
over a triangular space, while on either side they exhibited
signs of the greatest violence. An oak sill (e) which had
evidently been carried with the house until it struck, and
then hurled due east, was driven 4 feet into the soil, at an
angle of 45°. Its dimensions are 16 ft. x 8 ins., and its
estimated weight 300 lbs. It was found 18 yards east of
where the house struck.

Mrs. Waters was carried with the house until it went to
pieces, and received injuries of which she died. The frag-
ments of the house were carried far in the line of the storm.

Alexander Gibson had two houses, both situated as nearly
as possible in the centre of the storm. The first house
struck was taken away without touching the ground, and
went to pieces in the air. The other house, in which were
seven persons, was swung round on its north-west corner, as
on a pivot, the south end travelling 36 feet, and cutting up
the ground as it went. It then turned over, and was demo-
lished. During this journey the floor was broken up, and
three persons fell into the cellar. The house was a large
one. It afforded no good basis for calculation, on account
of the irregularity of its shape. A granary was pushed due
east 14 feet: its dimensions are 16 x 8 feet; it is strongly
built of generally hard wood, and divided into compart-
ments: it was full of grain. The weight of the building
and grain was given at 60,000 lbs. The resistance to its
forward motion was very great, because it was surrounded
with wet straw and rubbish, of which it had pushed quite a
pile before it: it was racked by the strain which had been
put upon it. Missiles had been driven through three hard-
wood planks, in succession, of an inch thick ; they consisted

1874.] The Iowa and Illinois Tornado. 361

of small pieces of wood, but had been removed. A plank
16 feet long, 2 inches thick, and 1 foot wide, was driven
4 feet into the soil, at an angle of 45. A corn-sheller,
weighing 640 lbs., was carried 400 yards, and destroyed.
Trees were barked, but without any symptoms of electric
action or of explosion. The general position of trees and
ruins was entirely corroborative of what has been already
proved by an overwhelming mass of evidence, viz., the
rotation and dire¢tion of rotation of the storm.

J. K. Marbourg, Jackson Township, Section 17, whose
house was 80 yards from storm-centre, with an excellent
view of Gibson’s house, watched the storm a long time
before it came. The west was first filled with clouds, which
extended until they covered all the western and northern
heavens, reaching a little beyond the zenith. The tornado
first appeared as two clouds, one from the south-west and
the other from the west rushing to one point. ‘Together
they presented somewhat the appearance of an arrow, thus :—

Fic. 24.

oo Dd
—

roa

The whirl was seen forming when they met. Above them
were dark, heavy clouds. When the tornado came nearer it
presented ‘the appearance of one funnel, revolving contrary
to the hands of a watch, and drawing everything up.

This witness related what he saw as follows :—‘‘ When at
Gibson’s house, where I had the best view of it, and where
it was 120 rods distant, it presented the appearance of two
funnels uniting in one, at the height of 40 or 50 feet. The
bases of the two funnels were about 200 feet apart :

362 The Iowa and Illinots Tornado. (July,

they presented somewhat the appearance represented in
Fig. 26. The two funnels did not appear to revolve around

Fic. 26.

each other. The first came to the east of Gibson’s house,
took his stable, and then turned back to his house. The
two then appeared to unite. Could not see the two after-
ward. The tornado disappeared behind a building. It grew
very dark. The funnels were of a dark blue; everything in
them was rising. The timbers from Gibson’s house flew up.
Did not see clear sky through the open space between the
two funnels, but a bright yellowish hue. ‘The upper funnel
extended to the clouds above. Hail, or rather chunks of
ice, from a pigeon’s to a hen’s egg in size, fell before the
tornado column came in sight. The wind then blew gently
from the east. After the tornado had destroyed the school-
house there came a violent gust of wind from the north-
west, which considerably damaged my out-buildings. I had

started to go to the school-house, and it carried me several

yards before it. Immediately there fell a torrent of rain,
with cold wind from the north. Was near where the school
had been, but could not see anything. Suddenly saw the
teacher and children, as if they had sprung out of the earth;
they were coming toward me; they were shivering; they
could give no account of what had befallen them; never
saw such miserable-looking beings in my life. I had four
children there, and did not recognise them. The mud was
pelted into their skins, so that it could not be washed out;
it is not all washed out yet. A dead child was found
40 yards north-west of the school-house. The storm oppo-

h

1874.] The Iowa and Illinois Tornado. 363

site my house was a mile wide. An oak post, 4 inches in
diameter, was perforated by an oak board 43 ft. x 4 ins. x
I inch.”

David Canier, Jackson Township, SeCtion 20, watched
the funnel as it approached. It was perfeCtly dark in it.
Could see boards flying out at the top of it. It was very
large at the top and small at the bottom. It grew dark as
night. Six persons took refuge in the cellar. The house
went immediately like the clap of a hand, and the darkness
was already gone. ‘Then it turned pretty dark again, and
rain fellina sheet. It did not fall indrops. It was all over
ina minute. ‘Things in the cellar were not much disturbed.
Bottles stood where they were.

Alexander Gibson, witness: Was at Mr. Canier’s house.
Hail as large as pigeon’s eggs fell about twenty minutes
before. Heard the noise about half an hour previous to
the storm. Saw clouds coming from the north and south,
and rushing together. Saw the funnel when three miles
distant. Watched it when 30 or 4o rods distant. It was
then as black as night, with boards flying around it. Avery
strong wind was blowing. It grew dark as midnight.
Rushed down into the cellar, and was barely down when
the house was struck with a sharp instantaneous rap, and
ina moment it was gone. It was dark on going down into
the cellar. It was pretty clear as soon as the house went.
it then grew dark again, and a tremendous rain came down.
Saw no lightning. Heard nothunder. A beam was driven
right through a hog.

Mr. Canier’s house was 24 x 28 x 14 feet to the eaves. It
was pushed 18 feet due north without touching the ground.
Its edge then came in contact with the soil and with tree
roots, having fallen 2 feet from its original position, and
the house toppled over, and was blown to fragments. ‘The
ruins were carried first to the north-west and then around
to the north-east. Heavy oak sills were carried hundreds
of yards and broken. ‘The strongest iron-bound machinery
was knocked to pieces and carried away. ‘The sickle-bar of
a Buckeye machine was carried 30 rods. A beam
14 feet x 6 x 63 inches was driven 3 feet into the soil in a
slanting position. The beam weighed about 50 lbs.

A half mile to the west of Mr. Canier’s house stood the
school already mentioned and a house occupied by Henry
Waters. Between these buildings and Canier’s house, and
Ioo yards to the north-west of the latter, passed the storm-
centre. The house occupied by Mr. Waters and the school-
house were first blown to the north-west, and then in a circle

364 The Iowa and Illinois Tornado. (July,

by the south round to the north-east. A hedge ran along
the road which connects the houses. It presented the ap-
pearances already described.

The house occupied by Mr. Waters was first blown to the
north-west, the sills remaining. The sills were afterwards
blown to the south-east. The sills of the school-house had
likewise, after being deserted by the house, been pushed to

FiG. 27.

Representation of Effects of the Storm at these Houses. @ shows the position of the School.
b, Waters’s House. ccc,the Road. d, Canier’s House.

the south-west, and, finally, the position of the débris among

the ruins showed there had followed a violent wind from the

north-west; thus a tree lay across the foundation of the

school from the north-west.

L. B. Babcock, son of J. P. Babcock, Jackson Township,
Section 17, said that: Hail fell before the storm as large as
pigeons’ eggs. Ran to get into the cellar. Cellar door was
blown over me as the house went. Came out of the cellar
immediately and was blown south. The rain then came
down in sheets with a north wind. The shutters from the
house were carried 3 or 4 miles at least. Jacob Zek got
only partly down the cellar stair and was hurt in the head.

. P. Babcock’s house was 34 xX 26 x 14 feet to the eaves.
The gable end faced the wind. The house was pushed
bodily towards the north, crushing the northern foundation,
tore up the ground a short distance, toppled over, and went
to pieces. It stood on the south-east of the storm-centre.

Mr. Zek’s house stands on the north-west edge of the
storm. It was pushed from its foundations 12 feet to the
S.S.W., ploughing up the ground. The windows on the north —

1874.] The Iowa and Illinois Tornado. 365

side were smashed in. The windows on the south and east
were blown out. A haystack was entirely blown away. It
went, as could easily be traced, first S.S.W., and then round
in a circle to the north-east. It went 40 rods south before
turning east.

=
Sketch of the Effeéts of the Storm at Babcock’s and Zek’s. aa, the Road.

The distance between these houses was about half a mile.
At this point the storm-path turned a little nearer north
than north-east.

F. M. Curry, Jackson Township, Section 9, tenant of
John Flack’s house, said: The family went to the cellar.
The house went south. No one injured. Eighteen pigs
blown away.

The house was pushed 45 feet due south and then went
to pieces. No explosion. It was situated to the north-
west of the centre.

E. N. Wright, Jackson Township, SeCtion 10: Was on
the south-east side of the storm. Saw distinctly, at the
distance of 2 miles, the tornado in funnel shape. ‘The small
end was down. Saw wood whirling. Heard its roaring
after it went east. There appeared to be a mist or steam in

VOL. Ly. (N.S.) 34

366 The Iowa and Illinois Tornado. (July,

front of it. It rose and fell. Hail fell before the tornado,
and an exceedingly violent rain after it.

Mr. Wright’s house stands on the north-west of the centte
of the storm-path, about 50 yards from it. A wood-house
and a kitchen were blown south-west. The dwelling-house
—a large stone structure—was moved 1 inch to the east.
A stove weighing 450 lbs., and exposing to the wind a
surface of 3 feet by 21 inches, was pushed 12 feet to the
south-west, where it was stopped by obstructions. A bell,
weighing 115 lbs., not under any circumstances exposing a
greater surface than 1 square foot to the wind, and mounted
12 feet high, was broken from its fastenings, and carried
60 feet south. A granary, measuring 28 x 16 x12 feet, and
weighing, together with the grain, 55,000 lbs., was carried
21 yards to the south-east. After ploughing up the ground
2 feet in depth, it tumbled over and went to pieces. It was
carried down a declivity, falling 6 feet. The width of the
storm-track here was half a mile.

.C. Cunningham, Jackson Township, Section 11: The
house of Mr. Cunningham stood on the north-west of the
centre of the storm-track, yet within the most violent vortex.
The house was blown to the south-west ; but the east door
having been blown in the house went to pieces without
tumbling over, and the floor remained upon the ground.
The lighter furniture, &c., was carried far to the east. The
granary stood to the north-east of the house. Its contents

were emptied into the house cellar. The sills of the granary ~

had remained where it was carried away. ‘They were after-

wards pushed to the south-east. The barn was blown to —

the south-east. A hog, weighing 200 lbs., was carried 500
yards. A cow, weighing 1000 lbs., was carried 200 yards.

Fic. 29.
N
w ™~ P E
ky
mr ak,
a
—— <—
ar Ah it ee *
Ss
Plan of Ruins. a, Sills. 6, Lighter Furniture.

There were four persons in the house and none were
killed. The path of the storm is here 500 yards wide, and
nearly due east.

rae ens Dee

1874.) The Iowa and Illinois Tornado. 367

D. T. Carringer, Jackson Township, Section 15: The
house stood on the south edge of the storm. It was carried
to the north-east 17 feet, going deeper into the soil as it
went. It then turned over and was blown away in frag-
ments. The straw among the trees showed that the last
gust came from the north-west.

Another house struck was that of J. M. Davidson, High-
land Township, Section 7. It stood precisely in the storm-
centre, which here, as if conscious that this was its last
victim in Iowa, seems to have exhausted its utmost violence.
The house, 18x12x14 feet, was blown bodily from its
foundations down a declivity towards a slough. It never
touched the ground, but was shattered in the air. It seems
to have been carried first nearly due west and then the

Fic. 30.

Plan of the Ruins. a, Davidson’s Body. 6, Housel’s Body. c, Mrs. Davidson. d, Heavier
portions. e, Lighter portions. f, Stable. g, Log.

lighter portions round in a curve to the east. The body of
Mr. Davidson was found 20 yards west of where the house
stood. The child was blown still further in the same
direction. Mrs. Davidson was carried about I00 yards
west. The body of Leyden Housel was found to the south-
east. The heavier portions of the house were found some
hundreds of yards to the west. Mr. Housel’s body had
evidently been carried west with the fragments of the house,
and then back to the east. Mrs. Davidson and the child
escaped with their lives.

A log of green water elm, 7 feet in circumference, 8 feet
in length, and weighing at least a ton, was carried 50 yards,
Straight south. A horse, weighing 1080 lbs., was carried
45 yards. A hog weighing 300 lbs. was blown 30 yards.
The stable and barn were blown south. An iron plough,

368 The Iowa and Illinois Tornado. (July, —

with wooden handles, was carried 150 yards. The
strongest iron-bound machinery was utterly destroyed. The
young trees in the orchard were either barked or torn out.
The storm was exceedingly violent for a breadth of
150 yards, but fences were blown down for nearly a mile ~
wide. At,the house of Thomas Davidson, a quarter of a
mile to the north, the wind blew so strongly that the door
had to be held. The north wind was evidently subsequent
to the east wind, because the house could not have stood
such a wind.

A. Davidson, Highland Township, Section 7, witness :—It
commenced to rain about ten or twenty minutes before the
arrival of the tornado. Shingles and other stuff began to
fall with the rain. Then went out to see where they came
from. Saw the tornado about 30 rods distant ; it appeared
to be coming toward me. Saw it bend to the south-east ; it
was funnel-shaped, and as black as possible; it whirled;
thought it whirled with the hands of a watch; it passed
20 rods to the south of the house, and bent again to the
north-east. When 30 rods distant from the house it sud-
denly disappeared. Afterwards saw another funnel, not
reaching to the ground, travelling toward the north-east.
When first seen it appeared to be only 60 feet above the
ground at its lower end. ‘The farther it went the higher it
seemed to get.

Mr. A. Davidson’s house is situated } a mile east of where
J. M. Davidson’s house stood, and a little north. The
shingles and other material he saw falling came from his
brother’s house. The following sketch shows the direction

Fic. 30.

a, Davidson’s House. 6, Major Davidson’s House. c, Disappearance. d, Fence.

of the storm-path after leaving Major Davidson’s place
until it ceased to touch the earth as a funnel; 20 rods south
of A. Davidson’s house it crossed a fence, exhibiting the
same appearances as those already described. I was parti
cularly careful upon this point, because of Mr. Davidson’s

1874.) The Iowa and Illinots Tornado. 369

belief that the funnel whirled with the sun. I thought it
possible that the tornado, before lifting from off the ground,
might have changed its direction of rotation. But the evi-
dence to the contrary was so striking that Mr. Davidson at
once, upon my pointing it out to him, admitted that he must
have been mistaken. He had not paid particular attention
to the matter, and it was very dark when his observations
were being made. The fence in question ran north and
south. It was only thrown down for a space of 60 yards,
and the boards were not carried away except in the middle.
The posts remained in the ground, those on the north of the
centre leaning west and those on the south leaning east.
The posts in the centre were leaning some one way, some
another. The funnel disappeared upon a knoll in the midst
of a hollow about 4 a mile in diameter. There was no
débris deposited at this-point, nor were there any signs of a
cataract of water having poured down. ‘The wheat, how-
ever, was mown as low as possible, and the ground looked
as if it had been baked, according to Mr. Davidson’s state-
ment. The funnel had narrowed to a point before it
disappeared.

After leaving Mr. Davidson’s the tornado cloud travelled
to the south-east. Its progress was now difficult to trace,
because of the little attention usually paid to a dark cloud,
a high wind, and a rain storm. Considerable time had also
now elapsed since the meteor passed.

The storm passed out of Washington County into Louisa
County, travelling south-east.

Joshua Luckey, Louisa County, Union Township, Sec-

ion 17, witness:—The path of fences blown down on my
farm was about 600 yards wide. The fences on the west of
the centre were thrown north; those on the east were thrown
south. Some hail fell, and a smart shower of rain. Heard
no roaring after it passed.

Charles Crim, Union Township, Section 20, witness :—
Fences, 200 yards wide, thrown down to the south-east.
The roaring was very loud for an hour previous to its arrival.
Did not hear it after it passed. Saw no lightning. Saw a
tongue of cloud shaped like a funnel hanging from the
clouds; it did not reach the earth; at first it was hanging
perpendicular, then it commenced whirling like the tail of a
suspended snake.

At this point I lost track of the tornado, and could not
recover it, although I spared neither time nor pains. The
inhabitants of this county appear in general to be not nearly
so intelligent as those of Washington County. Only now

370 The Iowa and Illinois Tornado. (July,
and again could one find a man who could give any informa- ~
tion even of what happened on their neighbour’s farm a
week or two before.

At this point I gave up the search, and took train for
Illinois. Previous to describing its effeéts there the following
testimony may find a place :— .

H. C. Vittitoe, Warren Township, Keokuk County, about ~
3 miles north-west of the tornado, witness :—Saw a little
south of the zenith the white under-clouds rushing in circles
toacentre. The gyration was contrary to the hands of a
watch. The funnel had not yet touched the earth. The
wind came from the north-west pretty strong after the
passage of the tornado, bringing with it a little rain and
hail.

Dr. W. D. Hoffman, Sigourney, witness:—Mrs. A. T.
Page colle¢ted a number of the largest hailstones. When
melted, it was found that they had contained a quantity of
twigs, leaves, dry grass, and mud, all reduced to fine pro-
portions. Hailstones weighing from 4 to 8 ounces were
common. One hailstone, which was shaped like an apple,
measured 44 inches in diameter. The roaring was heard
about twenty minutes before the hail began; it rose and fell
like the cannonading in a battle. During the hail the wind
came from the north-east, but it was very light.

Sigourney is 4 miles north of the storm.

Extracts from a communication received from R. L. Jay,
Harper, Keokuk County, physician :—

‘‘ Was in the village of Baden, Keokuk County, German
Township, 3 miles to the north-west of the storm-path.

‘‘The tornado maintained an upright position. It moved
rapidly at times, at others seeming to remain quite still.
It was apparently about a quarter of a mile in height, and
was funnel-shaped, and very dark and angry-looking. It
whirled with the hands of a watch. There was a continual
whirling of the clouds above the funnel: this was observed
for some time after the storm had passed. Saw no lightning
and heard nothunder. It was impossible to hear thunder
owing to the noise of the storm, which was terrific. The
direction of the wind was north-east until the storm had
passed, when it changed to the north-west. Rain fell in
torrents. Quite an amount of hail fell, of all conceivable
shapes: three hailstones were picked up weighing 3 1b. each.
Half an hour after the storm the thermometer stood at 92°.”

Extract from the ‘‘ Sigourney News,” May 28, 1873 :—

‘‘ While the cyclone was mowing its path a few miles
south and east of Sigourney, a tremendous _hail-storm

|

1874.] The Iowa and Illinots Tornado. 371

visited this locality. We saw one hailstone which weighed
81 ounces. The hail-storm was followed by a heavy rain,
after which the sun came out bright and pleasant for the
rest of the day.”

Extract from the ‘ Washington County Press” of May
28, 1873 :—

‘‘ The writer was in a street car, half-way from Moline to
Rock Island, at 4.30 P.M., on Thursday, when it was struck
dead ahead by the most terrific wind and rain storm we
ever experienced.”

S. J. Mather, editor “‘ Wilton Chronicle,” Iowa, witness :
Between 4 P.M. and 6 P.M. a very dark cloud passed over
which poured down a very heavy rain.

Extract from the ‘‘ Chicago Tribune,” May 25, 1873 :—

“At Muscatine the rain came down as if the flood-gates
of Heaven had been opened, followed by hail, Between
there and Wilton Junction, at Monona, Fredonia, and other
stations along the south-western division of the Chicago,
Rock Island, and Pacific Railroad, the country was flooded.”

The tow-boat Victory lost her pilot house and smoke-stack
when near Buffalo, on the Mississippi. The tug Nonesuch
lost her smoke-stack and pilot-house at Moline. She was
driven ashore.

A. H. Swan, editor of the ‘‘ Monmouth Review,” witness:
There was an exceedingly heavy rain, a little hail and a
great deal of lightning about 5 p.m. ‘The atmosphere smelt
as of brimstone previously. It was oppressively hot ; per-
hapsg5°.

The temperature and pressure on May 22, 1873, at places
near the tornado :—

DAVENPORT. KEOKUK. WEsT UNION.
————_—. — ——
Bar. (hhere bate here barer ebhers
wees... «20°73 «64° 20764 «(69° 20°40 Ox
PEEMMaSs J. . 20°60 77 20°51 °85 20°40 G5

fee. = = 20°00 66 26°71 ~72 20°53 64

The condition of the barometer and thermometer at West
Union was obtained from Frank McClintock, correspondent
of the Smithsonian Institute, who also furnishes the follow-
ing noteworthy fact :—‘‘ Wind changed from the south to
the west rapidly at 3.45 P.M. It worked back to the south
before 9 P.M.” The relative humidity at—

DAVENPORT. KEOKUK.
MMe ols aa 94 85
PR Re tee et we ol el Ne ig] 54

7 UMS ee ne 94 85

372 The Iowa and Illinois Tornado. [July,

We do not, therefore, overrate the relative ‘humidity when
we estimate it at 65 per cent at 2 P.M. The average tem-
perature at the earth’s surface in the line of the tornado at
2 P.M. was, from the above, probably 76°, but in the wooded
hollows much greater.

Mr. Jay, however, of Harper, Keokuk County, states that
the temperature was 92° half an hour after the storm. The
day was generally described as being very warm.

Having arrived at Prairie City, Illinois, I endeavoured to
find out the exact locality where the tornado first began to
overthrow fences, damage buildings, &c. On the farm of
James Williams, Point Pleasant Township, Warren County,
there was a strong wind, but not sufficiently strong to pro-
strate fences. About 1 mileto the east is the farm of Israel

Jared, Point Pleasant Township, Section 24. Mr. Jared ©

testified as follows :—Saw streaks of cloud moving from the
north and south toward each other before anything touched
the earth. Saw a cloud in the form and about the size of a
haystack strike the ground on my farm. A few minutes
before hail of moderate size and in small quantity fell, fol-
lowed, as the whirlwind was passing, by a smart shower of
rain. The wind, which had been south-east, changed to
the west after the tornado passed. It was pretty warm
before, and cool after it. Heard roaring some five minutes
previous to the arrival of the storm. Fences were blown
down for 200 yards wide. They were blown toward the
east. Saw some lightning. There was a heavy cloud to
the north as the storm approached.

Mr. Jared’s house stands about 200 yards north of the
storm-path. The tornado was here travelling a little to the
north of east.

John F. Tatman, Israel Jared’s farm, testifies that he saw
the funnel strike the farm, and that he heard the roaring for
a long time previous.

Before leaving this farm the storm had developed all the —

characteristics of a tornado, except that the east wind was
not yet powerful enough to destroy. The whirlwind then
passed along a ravine full of tall timber. Nearly all the
trees were uprooted or broken, but generally the latter.
‘They appear to have had a firmer hold of the soil than those

in Iowa. The breaking usually occurred about 6 feet from
the ground, and the barking was almost entirely confined to”

the broken trees. The bark was torn off both up and down
from the place where the timber was broken. The trees,
when sound, were seldom broken clean across. Half or
more of the wood was severed and the remainder was bent

1874.] The Iowa and Illinois Tornado. 373

so as to allow the tree to rest upon the ground. The
broken timber, when sound, invariably presented the appear-
ance of a broom. ‘The fibres of each year’s growth were
loosened from the others and split. It was easy to obtain
pieces ro feet long and as thin asa wand. This separation
of the fibres had evidently been brought about by the ex-
cessive straining and bending of the tree before it fell, Each
year’s growth had apparently been snapped asunder by itself,
beginning at the outside. The trees all lay as they had
fallen, being, when once down, protected by the surrounding
timber. If they had, after falling, been subjected to a wind
from another direction, so as to break them off entirely, they
' would have presented the precise appearances which have,
by certain meteorologists, been attributed to the action of
electricity. Many of these broken trees were 2 feet in
diameter. When a tree, still standing, had its bark torn off
at any point, an examination generally showed that the
fibres of the tree were separated and perhaps partly severed
at that point.

The path of the tornado was exceedingly well marked
among the young trees. It could be followed by the eye as
far as the ground permitted. They were torn and bare,
while all around was green. This barking of the young
trees took place within much narrower limits than those
within which grown timber was overthrown. Generally it
did not extend over twenty to thirty yards in width, and
was sometimes much less and even disappeared altogether.
The trees exhibited the marks of the greatest violence on the
side from which the storm came. The twigs were smashed
and broken off, the bark partially removed, and even the
timber bruised. These results were evidently the effect of a
rush of missiles against the trees.

The tornado at one point suddenly narrowed the path of
extreme violence from 50 yards to 12 yards, at the same
time changing its course to the south-east. This change of
direction brought it toward Swan Creek, along the northern
bank of which it had hitherto been raging. Just as it struck
the creek the track was nearly S.S.E. Immediately there-
after it turned nearly due east, following the creek. The bot-
tom of the ravine, within which Swan Creek flows, is about 200
yards wide, is surrounded by steep and lofty bluffs, and was
covered with large trees. Among these trees the whirlwind
raved with the utmost fury, developing an energy surpassed
at no other point in its career. Trees from 3 feet to 4 feet
in diameter were snapped or uprooted. Many large trees
were broken off at a height of about 4o feet and left without

VOL. IV. (N.S.) 3B

374 The Iowa and Illinois Tornado. (July,

a twig. By far the greater number of trees along the
ravine were thrown down from the south-west. The same
broom-like appearance was generally presented by the
broken trees as already mentioned.

Thomas Warmoth’s house stood in the bottom of the
ravine. Mrs. Warmoth testified as follows:—Heard a
roaring first. When the storm came near the roaring was
louder than thunder. Some hail fell just before the tornado
blew. It was immediately preceded by a very bright flash
of lightning. Went into the house and got upon my feather
bed, together with my child, because I was afraid of the
lightning. A large tree was blown down, catching the side
of the house. The house went to pieces, the tree, however,
keeping the floor in its place. Found myself under the
feather bed with my child. The bed was pinned to the
earth by pieces of timber. Was soaking wet. Everything
was covered with mud. Heard nothunder. The lightning
struck a tree, depriving it of its bark.

I was unable to find this tree. Mrs. Warmoth’s testimony
is valuable as a curiosity. It was generally impossible to
obtain any information from the ladies. If one questioned
them rigorously they took it as an insult, and if allowed to
tell their own story they immediately commenced running
such a muck among the prodigious and the incredible that
one was glad to make his escape. In this conneétion it is
also worth mentioning that although invariably offering pay-
ment for any necessary hospitalities, I soon learned the
wisdom of always addressing myself to the master of the
house when asking for such.

After leaving Warmoth’s house the tornado-centre crossed
to the south bank of the creek, where it continued for
nearly a mile farther, although somewhat increasing its
distance from the creek. It crossed to the south bank
where a smaller creek joins Swan Creek from the south.
This brought it nearer to the house of A. J. Caton, Swan
Township, Section 15, which stands about 500 yards from
the centre of the whirlwind. Part of the roof was blown to
the south-east and part to the north-east. A smaller house
was blown a few yards to the north-east and inverted. A
house on Mr. Caton’s farm, tenanted by N. J. Reynolds, 14
feet by 20 feet and one story high, was carried 8 yards to
the north-east bodily. It then struck the ground, tumbled
over, and was blown to fragments. Its four inmates were
carried from 50 to 60 yards, but not killed: It stood a
little south of the centre. After passing Mr. Caton’s farm
the tornado entirely left Swan Creek.

1874.) The Iowa and Illinois Tornado. 375

After leaving Swan Creek the storm travelled E.S.E. The
first house which came in its way was that of Absolom
Vandevere, Swan Township, Section 15. He testified as
follows :—I have reliable information that two or three miles
to the north the clouds were seen rushing south. The
clouds came also from the south toward the tornado.
Streaks of unusually strong wind seemed to come now and
again from the south side and run into the main whirl.
The wind on the north side was not nearly so strong as on
the south side. Twice as much fence was blown down on
the south as on the north side. Its noise resembled that of
machinery, only very loud. The dimensions of my house
were 36 x 42 x 18 feet.

Samuel Larkins, Swan Township, Section 15 :—Was at
Mr. Vandevere’s house when the tornado struck it. Heard
roaring about 15 minutes before it came. When I first saw
the funnel it did not touch the ground. Saw it whirling
contrary to the hands of a watch, and the clouds were
drawn in toward it on all sides. It did not lighten before
the storm. It lightened a great deal immediately after it in
the west. It did not hail nor rain. Did not see clouds in
north or south. There appeared to be only a narrow strip
of clouds. A McCormick reaper, weighing probably 1000
lbs., was carried ten rods from the south. ‘Two horses were
blown, the one 50, the other 40 yards. An axle-tree, torn
from a waggon, was carried a mile and a quarter to the
south-east. A shingle was driven through a half-inch ash
board. It is in the possession of a Mr. Thomas. A rafter
8 feet x (2x4) inches, was driven through three hogs and
thrust into the ground a foot and a half. All three were on
it when it was found. A picture-frame was picked up with
the glass unbroken. The wind blew very strongly for about
two minutes.

Mr. Vandevere’s house, 36x42x18 feet to the eaves,
stood north and south lengthwise. It was moved due north
half the length of the house, tumbled over and blown to
pieces. It stood with its north end exactly in the centre of
the vortex. There were nine persons in the cellar and two
in the house. One of those in the cellar was killed by a
log. The trees around the house and within the narrow
path of the greatest violence, all pointed to the E.S.E., the
direction in which the storm was travelling.

W. J. Jones, Swan Township, witness: Vandevere’s house
is forty rods to the north. Myself and wife were in my
house when it was blown away. It grew dark as midnight
just then. There was a little hail before. Did not notice
any rain. ‘The house did not go very fast.

376 The Iowa and Illinois Tornado. [July

Mr. Jones’s house was 22x 16x 12 feet to the eaves. It
was pushed entire 5 feet to the north-east. It then toppled
over and was blown to pieces.

Fia. 31.

Sketch of Storm Effects at Larkin’s, Vandevere’s, and Jones’s Houses.
a Larkin’s House; b Vandevere’s; c Jones’s.

The fragments in Illinois had already been gathered from
the fields, rendering it more difficult to trace. the ruins in
their flight.

William Thomas, Swan Township, witness :—The centre
of the storm passed a quarter of a mile to the north. An
unoccupied house stood in its way. It was lifted from its
foundations and then broken to pieces. Horses were carried
a good way and killed. A rail was driven through one of
the cattle, going in beneath her tail and coming out at her
shoulder. Saw only one funnel.

Such is a statement of some of the facts connected with
the Iowa and Illinois tornado of May 22, 1873. I spared
no pains in order to render it scientifically complete, some-
times travelling miles under a fierce sun, and with a tem-
perature among the nineties, in order to obtain the evidence
of one man. The information given by any witness by no
means represents the number of questions asked him.
These were extensive and calculated to extract all the
knowledge on the subject possessed by those under exam-
ination. For instance, the following question was addressed

=e

1874.] The Iowa and Illinois Tornado. 377

to all and sundry: Did you observe any pointed objects,
such as lightning-rods, posts, &c., tipped with flame, during
the progress of the tornado? but the replies being uniformly
in the negative, have not been formally inserted in the state-
ment of facts. Also a description of the sound was ex-
acted from all witnesses, but only a few typical ones have
been inserted. I regret this at present, because I have
learned from experience that very important questions may
attach themselves to a description of the sound. While
interrogating parties the utmost vigilance was exercised to
prevent them from giving conclusions for what they saw
and heard. This was a very troublesome point and caused
the interrogator to appear in many cases in the highest
degree rude; while it also excludes from these pages the
names of persons who observed accurately, but who are
unable to distinguish between the esse and the ergo.

The statement of facts for Iowa is much more exhaustive
and instructive than that for Illinois. There are several
reasons for. this.

1. Some weeks had already elapsed since the tornado,
and its traces were becoming rapidly obliterated, both in
the memories of the witnesses and upon the surface of the
earth.

2. It was later in the day when it occurred, thus hiding
the light of the sun more completely by the tornado clouds
as they approached, and rendering it more difficult to ob-
serve accurately their forms and proportions.

3. The storm in Illinois seems to have been of a some-
what different character from that in Iowa, by its form
rendering observation more difficult.

With regard to the angles of elevation given, it must be
borne in mind that they are only approximations. Very few
indeed of the witnesses have accurate conceptions of angles.
I generally made them point in the direction in which an
object was seen, and so estimated the angle.

CALCULATIONS AND CONCLUSIONS.

The Idea of a Tornado in General.—The tornado consists
essentially of a rapidly ascending current of air. This in-
volves two other fun¢tions—(r) a rushing in of the air at
the under part of the ascending current or column; (2) an
out-rushing at the upper. Upon the former of these
functions, combined with modifying circumstances, depends
the peculiar character and career of the under currents and
of the clouds they bear; upon the latter, combined with
the same circumstances, the proportions and direétion of

378 The Iowa and Illinois Tornado. (July,

motion of the upper currents of the heavy masses of clouds
they bear. There appears to be nothing in the nature of the
tornado itself which can determine the motion of either the
upper or under current more towards any one point of the
compass than toward the others. This direction of motion
relative to the ascending column depends upon the dire¢tion
and velocity of motion of the latter and of the atmospheric
strata in which the influx and efflux take place, modified to
some extent by the differing velocities of revolution of the
surface of the earth at different parallels of latitude, by the
form of the earth’s surface, and by the variation in the con-
stitution of the atmosphere. If the tornado column, and the
atmospheric strata which it penetrates, move in the same
direction and with the same velocity, the influx and efflux
will take place in nearly equal quantity on all sides of the
column. Ifthey move with different velocities the dire¢tions
of exaggeration and diminution of the influx and efflux can be
calculated in the same way as the direction of a wind-vane
on a ship’s mast, given the directions and velocities of the
motion of the wind and of the ship.

General Idea of the Tornado of May 22, 1873, in Iowa.—A
huge, dark cloud covered an area at least 30 miles in
diameter. Under the south-west edge of this cloud there
moved a perfectly opaque funnel-shaped appearance, reach-
ing from the ground to the clouds. Towards its base the
wind, in spirals, rushed violently from all sides, overthrow-
ing, when in immediate proximity to or within the opaque
vortex, whatever opposed its progress. Towardsits summit,
where it disappeared in overhanging horizontal cloud, long
streaks of clouds rushed in spirals from all directions.
Viewed from a distance they appeared to come from opposite
directions, and move swiftly towards each other at right
angle to the observer’s line of vision. Between the surface
current and these centripetal clouds the air doubtless obeyed
the same forces, and rushed in spirals with ever-increasing
velocity towards the opaque funnel.

Under the remainder of the lofty cloud which defined the
limits within which the outspreading of the ascending air
was taking place, and which lay chiefly to the N.E. of the
rising column, there raged a tremendous storm of hail and
rain, accompanied by incessant and brilliant electrical
phenomena.

More Particular Description, Dimensions of the Meteor, and
of the Centrifugal or Upper Current.—The data for deter-
mining the horizontal extent of the cloud are not very pre-
cise. There is a general concurrence of the witnesses that

1874.] The Iowa and Illinois Tornado. 379

it reached only a few miles to the south of the tornado, and
that very little rain or hail fell there.

There is also a general agreement among the witnesses that
a little hail fell some minutes before the advent of the funnel,
and a little rain immediately after its passage. The whole
appears to have occupied at least thirty minutes in passing.
This would give the cloud at the funnel a width of at least
15 miles in the line of its progress. Probably it was con-
siderably greater. We may, therefore, safely conclude that
we are within the limits where we assign to the centrifugal
cloud an average horizontal diameter of 30 miles.

I have no data for determining the elevation of the under
side of the centrifugal cloud beyond what is involved in those
for measuring the altitude of the centripetal. There must,
however, have intervened a very considerable space between
the two. For if there was nothing intervening there could
be nothing to prevent the under, and specifically lighter,
air from taking the shortest way up. There could be no
reason why it should first rush to a centre, ascend there,
and then rush from it.

Dimensions of the Centripetal Current.—The data for deter-
mining these are still less precise than the preceding, but
yet sufficiently so as to give a more definite idea than any
mere description in general terms.

The witnesses generally testify that hail fell from fifteen
to thirty minutes before the whirlwind, and rain for as long
a period after. They further almost unanimously say that
the wind was easterly with the hail and westerly with the
rain. If we assume twenty minutes as the duration of each
of these winds, we obtain 20 miles as the diameter of the
inrushing winds at the earth’s surface.

If the disturbing influences were not much greater at the
earth’s surface than at a higher altitude, the dimensions of
the whirl should, within the limits of the centripetal wind,
owing to the absence of friction, vastly increase as we
ascend. Moreover, since the funnel was first formed at a
considerable elevation, and since it touched the ground with
a narrow point, and merely incidentally, as it were, since it
for long distances ceased to strike the earth, and yet pro-
ceeded with undiminished energy; since, in short, both the
originating and sustaining sources of its power seem to
have mainly existed high in the atmosphere, we have the
Strongest reasons for concluding that the horizontal
dimensions of the centripetal current was very much greater
at its more elevated portions than at its base. It would
therefore appear to be not unlikely that the diameter of the

380 The Iowa and Illinois Tornado. (July,

centripetal current was not greatly exceeded by that of the
centrifugal.

The Dimensions of the Funnel.—The data for calculating
the dimensions of the visible portion of the funnel are
more numerous than precisely accurate; but I conclude that
the tornado column was, from a favourable position, visible at
some parts of its course to a height of between r and
2 miles.

Wherever there was evidence of the funnel having
touched the ground there was, to a greater or less breadth,
what I have designated as the vortex of extreme violence,
varying from roo yards in breadth to nothing. Without
having positive evidence, and notwithstanding that there
was everywhere a gradual diminution of violence from the
centre to the circumference except in the remarkable
phenomenon of streaks or arms, and no abrupt transitions,
I could not help concluding that the path of greatest violence
was identical, or nearly so, with the diameter of the base of
the funnel when it touched the ground. This would give it
an average diameter of about 30 yards. The witnesses are
generally agreed that the summit was several times wider
than the base. If we assume that the visible top was five
times the diameter of the base, we have, say, for the altitude
of 1 mile, a diameter of only 150 yards. I think, however,
that, owing to its great elevation and the optical delusion
connected therewith, and the general belief of the spectators,
that the funnel was, at the very utmost, only a few hundred
feet high; the diameter of the summit was very much greater.

The Changes scen in the Funnel.—Some observers saw only
one funnel, others saw two funnels superimposed with the
narrow ends together, and the smaller one beneath, while a
great many saw two and even three funnels side by side.
The evidence on all these points is beyond question. At
first I was inclined to believe that two or more funnels had
actually touched the ground and travelled side by side. The
sketch of the storm by R. F. Campbell seemed to favour
this explanation. It shows a protuberance on each side of
the funnel, which looks like an inceptive funnel. The fact
that a second funnel should travel along the south-east side
of the main one without disturbing the symmetry of the
action of the latter, as exhibited by the ruins, did not appear
altogether incredible, for it is abundantly evident from the
statement of facts that the damage was done by a wind
blowing in the path of the tornado when the black funnel
hovered above or slightly touched the ground. Thus an
incipient funnel, moving along the south-east side of the

1874.] The Iowa and Illinois Tornado. 381

main funnel, and occasionally making a dip, would produce
no appreciable discord in the disposition of the ruins. An
insuperable objection to this theory was found in the
unanimous testimony of the eye-witnesses that the funnels
approached each other and combined to form one. Another
objection was found in the lack of unity thus introduced
into the conception of the magnificent whole. Finding this
explanation untenable, I endeavoured to think the possibility ~
of smaller auxiliary funnels, each of them a perfect whirl,
moving in spirals nearly or altogether identical with those
pursued by the confluent winds. This I found to be more
difficult than the first. The chief objection was the total
lack of a conceivable cause of the existence of these smaller
whirls. The second was the peculiar circumstance that
while one observer saw two funnels, another in the same
position saw only one, or saw two superimposed with the
smaller ends together. No possible arrangement of two
independent funnels with the smaller ends down could pro-
duce the optical illusion of the funnels superimposed with
the smaller ends together. I found what I believe to be the
key to the difficulty given by Mr. Marbourg while considering
the delineation of the two funnels joining in one funnel.
The other observers who saw two or more funnels evidently
had the whole of their attention confined to these, and did
not observe what was above them. He saw the two com-
bine at what he estimated an altitude of 50 feet, and form
one. Another witness at the same place and time saw only
one funnel. At Lancaster some saw only one, others saw
two superimposed, and others saw two side by side and all
at the same time. ‘There is, therefore, an unavoidable
necessity for some explanation to reconcile these antagonistic
appearances.

There is excellent evidence to show that the funnel moved
at its base with a sort of pendulum motion; that it seemed
to stand still for a moment and then to bound suddenly
forward. ‘The evidence on this point is so general that we
need not recapitulate it. But we have no reason for
supposing that this oscillating motion extended to any con-
Siderable distance above the ground, for it is only in the
want of homogeneity of the atmosphere and the resistance
opposed to the free course of the winds by the earth’s sur-
face that we can find a cause for this pendulum motion.
Let us suppose that the funnel is over a well-watered and
well-wooded ravine, with its path at right angles to it. It
is evident that the air at some distance above the ground
wiil offer much less resistance to the forces drawing it into

VOL. IV. (N.S.) Z¢

382 The Iowa and Illinois Tornado. (July,

new paths than that on the surface when the friction is so
important an element. Inthe forward march of the tornado
the base would thus be somewhat left behind. The warm,
moist air of the ravine would increase this tendency on ac-
count of its specific levity.

But the inrushing winds follow the path of least re-
sistance toward the area of greatest rarefaction. The
bending, therefore, cannot proceed far before the south-west
winds, whose direction of motion is carrying them away
_ from the base of the inclined funnel, will find less resistance
and a shorter path towards the greatest rarefaction by striking
up into the nearest point in the side of the funnel.

A streak of rarefaction great enough to produce conden-
sation is thus generated. This arm of the funnel affording
the shortest way for the winds will increase with rapidity.
The other will decrease, becoming mainly confined to the
north-west winds. Meanwhile the intervening air will
become rarefied and set in motion; the two arms will
suddenly unite, and the funnel present again its original
proportions. ‘These transformations must take place within
a brief space of time, for the tornado is travelling at the
rate of half a mile per minute. When we consider, in
addition, the darkness, we shall be at no loss to conceive why
these two branches should present the appearance of one
funnel with its larger end down, and why to a less favourably
situated or more superficial observer the whole should appear
as one.

One difficulty yet remains to be obviated. Since the arm
moves forward ina spiral to the centre, and the velocity of
the inrushing winds at the funnel far exceeds 100 miles per
hour, how is it possible for the observer in the darkness to
notice the appearances distinétly ? Mr. Marbourg gives the
distance between the two arms at 200 feet. This space
would be traversed in one second by winds of so great
velocity, and the condensed vapour would fill the whole
space before it had time to disappear. ‘The very velocity
itself would render distinct vision difficult. ‘We must not,
in short, confound the path of the winds with the winds
themselves. While the winds were rushing up ina slanting
and curving direction along these arms, the arms themselves
might be moving forward with a much less rapid motion.
If it were possible to determine the inclination of these
arms to the perpendicular it would aid in calculating the
force of the wind. Mr. Marbourg stated that the distance
between the bases of the two arms was 200 feet, and the
height, when they joined together, 50 feet. He gave 80 to

—

1874.] The Iowa and Illinois Tornado. 383

100 feet, however, as the height, to the editor of the ‘‘ Wash-
ington County Press.” His own delineation formed the
belief that the height was greater than 50 feet. He could
easily judge of the distance between the arms, but was
very liable to be mistaken in estimating the height. The
error, therefore, will probably not be great if we assume that
the funnels joined together at the height of 100 feet. This
would give these arms an inclination of 45°.

The Direction in and the Velocity with which the Tornado
Travelled.—F rom its starting-point on South Skunk river
until it reached North Skunk river, a distance of 10 miles,
the tornado travelled in an E.N.E. direction. It there
turned a little south of east and followed the course of that
mivet for 2 miles. It then went E.N.E. until it came to
Rock Creek, when it turned a little west of north and
followed the course of the creek for a short distance. It
then travelled north-east until it ceased to touch the ground
3 miles from Keota. After lifting itself from the ground it
travelled about E.N.E., striking again at Westchester,
Washington County. From this point until it reached
Enoch Wright’s, a distance of over g miles, its course was
nearly straight, varying between N.E. and E.N.E. Its
course then became very crooked, bending in curves from
north-east to south-east, and vice versd; but on the whole
travelling east, until it came within a mile of the confines
of Washington County, when it made a decided turn to the
south-east. Here its path lay down the declivity towards
the well-wooded ravine of Goose Creek. When within half
a mile of the creek its traces became so feeble that it was
impossible to track it further. It was at this point, within
Iz miles of Iowa river, that the crookedness of its path
reached its maximum within the last half mile of its career,
before ceasing to touch the ground, as a black funnel
at A. Davidson’s farm, Highland Township. Within this
half mile it bent just a little to the south-east, then to the
north-east, then to the south-east, and again back to the
north-east, when it disappeared.

After leaving Crooked Creek, at the commencement of
its career in Washington County, and until it reached to
near Goose Creek, the tornado traversed an elevated, well-
cultivated region, almost totally devoid of trees and water-
courses. ‘There wasapparently nothing in the configuration
of the ground over which it passed which could account for
its changes of direction. ‘These changes, moreover, were
not generally abrupt, the tornado sweeping in graceful
curves from one direction to another. It is to be noted,

384 The Iowa and Illinois Tornado. (July,

however, that the curving of its path commenced after it
came within the influence of the moister warmer air of the
Iowa river, and that the general deviation of its course from
the north-east direction, which it had on the whole hitherto
followed, led it down the valley of the Iowa river.

In order to determine the velocity with which the meteor
travelled, it was necessary to obtain the precise time of its
arrival at different points. The difficulty of obtaining pre-
cise time in an agricultural district is always considerable.
In addition, no one thought of looking at his clock or watch.
Hence, although every witness was questioned on this point,
there were but few who could even approximate to the time.
The majority thought that they had a remarkably definite
idea when they could tell between what hours it occurred.
Reliable time it is believed was obtained at least at two
places in lowa—at Wolfden school-house, Lancaster Town-
ship, Keokuk County, and at A. McKee’s house, Section 23,
Cedar Township, Washington County. The times obtained
at these places were corroborated by the testimony of those
likely to be best informed. ‘The tornado struck the school
at 2.15 P.M. It arrived in SeCtion 23, Cedar Township, at
3.10 P.M. ‘The distance between these places in a straight
line is 27 miles. This gives a velocity of 29°4 miles per
hour. The crookedness of its course, though not great,
would bring its velocity along its path to 30 miles per hour
at least.

The Direction of the Centripetal Winds.—The wind blew in
spirals toward the centre of the vortex, the direction of re-
volution being contrary to the hands of a watch throughout
the whole course of the storm. ‘The evidence in support of
this, as given in the statement of facts, is overwhelming,
and recapitulation unnecessary. The mere fact that all who
had an opportunity of seeing the funnel saw that it was cir-
cular is sufficient to prove that it was a whirlwind, for on no
other hypothesis could the circular form be accounted for.
Then the witnesses, almost without exception, saw this
funnel whirling contrary to the hands of a watch. Then
the illustrations of the position of the ruins of the houses,
and of the fallen trees, &c., prove beyond a doubt that a
merely centripetal wind could not have done these things.
Again: that the wind was not blowing in circles round the
centre is sufficiently demonstrated by the fact that every-
thing, except within the most violent vortex, was thrown
toward the centre; the ruins invariably lay most thickly
there. The only form of motion capable of producing these
effects is a mean between the circular and the direct centri-

1874.| The Iowa and Illinois Tornado. 385

petal,—to wit, the spiral. The illustrations give copious
ocular demonstration that such was the case. The ruins of
houses, whenever they could be distinctly traced, proceeded
in the curve towards the centre, which apparently was always
reached before the completion of an entire revolution. This
does not imply that the centripetal winds never performed a
complete revolution before reaching the centre, but only that
from within about too yards of the centre this did not take
place. Ruins carried from that distance seemed generally
to reach the centre in about two-thirds of a revolution.
This led me to assume at about 100 yards from the centre
the wind generally made an angle of about 25° with the
tangent. This gives a centripetal component compared
with the circular as 0°42262 is to 090631.

Besides its horizontal motion, the wind had necessarily an
ascending motion, which reached its maximum at the centre
and its minimum at the circumference. The necessity for
this lies in the proof of the centripetal motion of the wind.
Otherwise the centripetal motion of the wind would require
to double itself at half the radius from any point toward
the centre : this would soon give it a motion infinitely great,
which is absurd; there would also be no means of escape
for it at the centre. To a great many excellent witnesses
the funnel presented the appearance of a screw with its
thread running upwards. In addition, all objects within the
sphere of the tornado seem to have been partly lifted, partly
pushed forward. We have seen that at A. Gibson’s house
the arms made an angle with the perpendicular of probably
about 45. Since these arms, as there is every reason to
believe, were inclined in the normal direction of the winds,
which is that of least resistance, we are justified in assuming
that in the black funnel itself the inclination of the winds
to the horizon was at least as great, and probably greater.

The Velocity of the Wind.—This is a very difficult topic ;
the task would have been much easier if we had been
dealing with a horizontal wind merely. If even the perpen-
dicular and horizontal components were invariable, the hope
of a tolerably accurate solution of the problem would be
much greater; but while the former decreases from the
centre to the circumference, the latter increases. In order
that no chance of a solution might be lost, I give the fol-
lowing from data I collected :—

1. A school-house, weighing 30,000 Ibs., was pushed
25 feet from its foundations. The surface exposed to
the wind = 360 square feet + the roof, which hada
slant of 45°.

336 The Iowa and Illinois Tornado. (July,

z. A house, exposing 280 square feet to the wind, having
a floor of 480 square feet, and weighing 20 tons, was
pushed 6 feet from its foundations. It was then
lifted over the tops of trees 20 feet high.

. A house, presenting to the wind a surface of 176 square
feet without the roof, and weighing Io tons, was car-
ried 24 yards while falling 3 feet. The wind struck
it nearly on the end.

4. A granary, exposing 128 square feet of surface, and

weighing 60,000 lbs., was pushed 14 feet.

5. A house, exposing a surface of 392 square feet, + the
slanting roof, and weighing 20 tons, was carried for-
ward 18 feet while falling 2 feet.

6. A house, exposing 533 square feet, and weighing about

25 tons, was pushed from its foundations.

. A granary, exposing a surface of 256 square feet to the
wind, and weighing 55,000 lbs., was carried 21 yards
while falling 6 feet.

SS)

“NJ

If we estimate the static friction of a frame house upon
a stone foundation, or upon posts firmly fixed into the
ground, and to which it is nailed, at one-half the weight of
the house, it does not seem likely that we shall err by excess.
Upon this basis it is easy to calculate the minimum velocity
of a horizontai wind necessary to push it from its founda-
tions. The difficulty is that we are dealing with a wind
having a perpendicular component to its velocity. If the
wall of the house was perfectly smooth, and since the air is
nearly perfectly elastic, the only force exerted upon it by awind
blowing at any angle to its surface would be perpendicular
to that surface. Moreover, whatever force the perpendicular
component may exercise upon the wall, owing to its rough-
ness, must have upon the house the effect of an overturning
rather than a lifting power. But, since friction is indepen-
dent of extent of surface, this overturning power would not
assist in overcoming friction. The fact, also, that the
houses, while being carried bodily through the air, were not
made to spin round on an axis by this perpendicular com-
ponent,—there being then no resistance, beyond inertion, to
motion in a circle,—would seem to prove that its effect was
not great. It would therefore appear that an approximation
may be made to the velocity of the horizontal wind, by
simply calculating—upon the given assumption of the rela-
tion of weight to friction—the minimum force required to
push these houses from their foundations. The following
are the results for the given cases :—

1874.| The Iowa and Illinois Tornado. 387

1. Pressure per square foot 41°7 lbs. Velocity of wind,
g1°3 miles per hour.

Pressure, 71°4 lbs. Velocity, 119°5 miles.

Pressure, 56°8 Ibs. Velocity, 106°6 miles.

f Eressure, 234°3 lbs. Velocity, 21675 miles.

Pressure, 51 lbs. Velocity, r00’9 miles.

Pressure, 46°9 lbs. Velocity, 96°8 miles.

Pressure, 107°4 lbs. Velocity, 146°6 miles.

Only one of these buildings was not, in addition to being
pushed from its foundation, carried away, ViZ., case 4. It,
however, was pushed through a dense mass of tough rub-
bish, and its sides were bent from the perpendicular.
Owing to its small surface and great weight, the force of the
wind exceeded the minimum required to push the building
from its foundations less in this case than in any of the
others. Hence we have the great velocity of 216°4 miles
per hour, or of 317°4 feet per second, in a horizontal direc-
tion. It is also probable that in this case the kinetic friction
was greater than the static, and that it increased every
moment until the building came to a stand.

The Amount of the Precipitation.—It was impossible to ob-
tain more than generalities on this head. There were no
rain-gauge measurements, so far as I could learn. At
Davenport, however, a few miles from where damage was
done on the Mississippi, there fell, on May 22, 1°35 inches,
as shown by the Signal Service Reports. From the descrip-
tion of the rain to the north of the funnel, in Washington
County, a greater quantity than this must have fallen at
many places. It is not, therefore, likely that we shall over-
estimate the amount when we assume that 2 inches of rain
fell over an area 10 miles in width. Since the tornado tra-
velled 30 miles per hour, this gives a rainfall per minute of—

2 X (10 X 2) X 3,097,600 X9 X 144 _

1728

Tornado Dynamics.—A cubic foot of water weighs ro000
ounces. The weight of water which fell per minute was
therefore—

23,232,000 X 1000

16
It is not, probably, an exaggeration to assume that this mass
of water fell, on an average, 6 miles or more. This gives a
horse-power oie
14,522,000,000 X (6 X 5280) _
33,000 Hs
generated by the falling water.

WOYEY

23,232, 000 cubic feer.

=1,452,000,000 lbs.

I,393,920,000,

388 The Iowa ae Illinois Tornado. (July,

From the calculations of the velocity of the wind it is
not probable that, when we assume—at the distance of
roo yards from the centre—an average velocity of 120 miles
per hour, we overrate it. The angle which the wind made
with the tangent was probably about 25°. The wind, there-
fore, on these bases enters a cylinder of 100 yards radius
at the rate of 50 miles per hour, or 4400 feet per minute.

From the calculations of the height of the centripetal
current we have seen that it probably extended over
2 miles. Let us assume that its height was 2 miles.
Let us assume, also, that the velocity with which the wind
entered the cylinder was equally great throughout its length.
We have then the following data for calculating the quantity
of air which enters this cylinder of too yards radius, or
628,318 yards circumference per minute. It amounts to
(628,318 x 3) X 4400 x (2 X 1760 X 3) c. ft. = 87,582,502,656,000
cubic feet. Since this volume is calculated from the me-
chanical effects or force of the wind, and since the relation
between the force and the velocity of the wind is calculated
for the average pressure, it matters not, in calculating the
mass of the above volume of air, what the barometric
pressure was at the distance of 100 yards from the centre.
The difference of pressure due to elevation must, however,
be calculated. Since the average pressure at sea-level is
about 30 inches, at an elevation of 1 mile about 24°60 inches,
and at an elevation of 2 miles about 20°20 inches, and taking
into account the correction due to the elevation of the
country over which the tornado passed, 24 inches would be
about the mean pressure up to 2 miles of elevation. The
density of the air varies with the temperature. The tem-
perature around the tornado must have been, at a fair
exposure, about 76°, but was in deep wooded ravines no
doubt much greater: since the temperature diminishes 1 for
every 300 or 400 feet of elevation, we may assume the
average temperature to have been, within the limits of the
centripetal current, about 60°. The relative humidity was
about 65 per cent.

The weight of a cubic foot of air, at a pressure of
24 inches, a temperature of 60°, and a relative humidity of
65 per cent, is 426 grs., or thereabout. The total weight of
air, therefore, entering the column per minute amounts to—

87,582,502,056,000 X 426 _
7000

This weight of air moves, by hypothesis, at the rate of
120 miles per hour, or of 176 feet per second. This velocity
is acquired from the acceleration due to gravity in falling

5330,020,875,922 lbs.

.

¥874.| The Iowa and Illinois Tornado. 389

through a space of 481 feet. The power, therefore, gene-
rated by this mass of air moving with the given velocity
amounts to—
5330,020,875,922 x 481
33,000

The latent heat of evaporation amounts to about 1000’.
Consequently the condensation of 1,452,000,000 lbs. of vapour
is accompanied by the evolution of 1,452,000,000 X 1000 ca-
lorics or pound degrees of heat. The specific thermal capa-
city of air, as compared with water, is as 0°237to 1. The
number of degrees, therefore, which this amount of heat
would raise 1 lb. of air is—

1,452,000,000,000 X Baa 6,126,582,278,481 degrees.

= 77,089,092,161,166 horse-power.

But the pressure remaining the same air expands zi; part of
its volume for every accretion of 1 degree of temperature.
This amount of heat would therefore expand 1 Ib. of air
6,126,582,278,481
491
air at 30 inches pressure, 60° temperature, and having a re-
lative humidity of 65 per cent, weighs 538°6 grains. A
pound of such air, therefore, occupies—
7000
538°6
A pound of air, therefore, in doubling its volume must—
the pressure remaining 15 lbs. per square inch—raise a
weight 13 X 144 X 15 =28,080 lbs. through 1 foot. The total
amount of work, therefore, performed by 1 lb. of air, while
expanding—under a pressure of 15 lbs. per square inch—to
12,477,764,315 times its original bulk, is 12,477,764,315 x
28,080 foot-pounds. This amount of work accomplished
per minute demands—
12,477,704,315 x 28,080
33,000
We thus see that the power generated by the condensation
of the amount of vapour estimated as having been precipi-
tated is much less than that calculated to have been produced
by the velocity of the centripetal winds. Theoretically, this
power should be diminished by the amount of expansion
counteracted by the removal of so large a mass of vapour.
Practically, however, it seems probable that this removal of
vapour, while increasing the specific gravity of the air, serves
rather to increase the rarefaction when taking place with
great rapidity.
VOL, IV. (N.S.) 20

= 12,477,764,315 times. A cubic foot of

=12-99—13 Cubic feet very nearly.

= 10,617,443,089°8 horse-power.

390 The Iowa and Illinois Tornado. (July,

The horse-power required to raise 5,330,020,875,922 lbs.
to a height of 5 miles per minute amounts to—

5,330,020,875,922 X 5 X 1760 x 3
33,000

= 4,264,016,700,737°6 horse-

power.

These figures convey a better idea of the tremendous
power of the tornado than any mere verbal description
could do. They also show that the power evolved by the
condensation of vapour, while enormous, is by no means
sufficient to supply the whole energy developed by the tor-
nado. We must therefore look for another source of power.
This is no doubt to be found in the destruction of the
atmospheric equilibrium by an abnormally warm southerly
current flowing under a much colder, and consequently spe-
cifically heavier, stratum of air.

In an extensive paper, which will be found in the Chief
Signal Officer’s Annual Report for 1873, the author passes on
to the consideration of the general atmospheric conditions
under which the tornado originated. The length of this
article, however, precludes our entering fully into this branch
of the subject.

The Electrical Phenomena must be regarded as. merely
secondary. In the lofty centrifugal cloud there was inces-
sant thunder and lightning; but very little, if any at all, in
the centripetal cloud and the funnel. One obje¢t, a tree,
was struck in the path of the storm, but the discharge took
place half an hour before the arrival of the funnel. The
lightning-rod said to have been melted on widow Dogget’s
barn might have been struck long before, and only noticed
then because it was blown down.

There were no evidences of electrical action upon the
trees, which were peeled and shivered by the storm, although
there was that brown appearance when the trees were broken
which has been referred to the action of electricity. This,
however, was clearly due to the straining of the tree before
it broke.

No one saw any objects tipped with electrical light during
the progress of the meteor. The telegraph was not inter-
rupted until the wind blew down the wires.

It is the generally-accepted opinion that in tornadoes
houses are frequently burst asunder when the centre of the
whirlwind comes over them. This is supposed to be accom-
plished by the great rarefaction, which is said to exist in the
centre, suddenly relieving the air within the houses of a large
portion of atmospheric pressure. The air thus relieved of

1874.] The Iowa and Illinois Tornado. 391

pressure immediately expands and blows the house asunder,
as with gunpowder. There was not, so far as I was able to
learn, a single case in which a house was so destroyed.
The houses were invariably demolished or blown from their
foundations by a wind blowing in a certain direction. They
were generally pushed or carried a considerable distance
bodily, floor and all. After striking the ground with the
foremost edge they turned partially over, thus exposing the
floor to the wind. The wind, being obstru¢ted by the wall
of the house resting on the ground, became immediately
compressed by the pressure from behind. The floor, unable
to stand this pressure, went upwards, and the whole interior
of the building became subjected to a strong pressure due to
the compression of the air. This pressure was more than
balanced on the side struck by the wind. On the other sides
there was nothing to resist it, and the house was accordingly
burst asunder.

We have therefore ample proof of explosion by com-
pression, but none whatever of explosion by rarefaction.

The temperature at the centre is easily calculated. We
have assumed, from the data, an average temperature of 76°
on the surface of the ground, and a relative humidity of
65 percent. This gives a dew point of 63°, or thereabout.
This sudden decrease of 13°, together with the wet, is suffi-
cient to account for the coolness experienced.

The lowering of the temperature at the centre of the tor-
nado is due to the work performed by the air in expanding
under diminishing pressure. The amount of this expansion,
and consequently of the diminution of pressure, is easily
obtained from the equation poe = a (“* Zeuner’s

I

Grundzuge,” p. 131), when a = coefficient of expansion
= 491, t = initial temperature — 32, ¢, = final temper-
ature — 32, v = initial volume, v, = final volume, and k
= the relation between the thermal capacities of the air
with constant volume, and with constant pressure = 1°41.
The initial temperature in the case of the tornado = 76°, and
the final temperature 63°. Consequently, t=76—32=44,
and ¢,=63—32=31. Letustakev=1. Then—

SH (2), or 535 — v4, or 1,= (339) 41 =
491+31 I 522

= Oa ke

A cubic foot of air therefore expands, in passing from the
circumference to the centre, to 1°8219 cubic feet. But the
pressure is inversely as the volume. Therefore, since the

392 The Iowa and Illinois Tornado. (July,

initial pressure was 28°5, ie = the pressure when the
dew point is reached and the funnel commences = 15°69.
This gives a diminution of 12°81 inches, corresponding to a
pressure of about 6°40 lbs. per square inch, or 922 lbs. per
square foot,—an amount of potential energy amply sufficient
to account for all the phenomena.

The form and dimensions of the visible funnel did not
therefore depend upon the diminution of pressure alone, but
also upon the temperature and relative humidity of the in-
rushing winds. Its presence accordingly does not indicate
a certain invariable velocity of the wind. When the air is
moist, as it always Is over the sea, a very small diminution
of pressure, and consequently a comparatively light wind,
would suffice to develop the phenomenon of a visible funnel.
When, on the contrary, the air is very dry, winds of the ut-
most possible violence could be produced without a visible
funnel. The funnel of dark cloud, therefore, by no means
indicates the limits of the ascending current. This renders
the explanation of the hovering up and down of the lower
end of the funnel easy of comprehension. Varying humidity
along the path of the tornado would be sufficient to produce
this phenomenon.

As the air ascends the pressure diminishes, and the funnel
consequently increases in width. The diminution of pressure
perpendicularly is symmetrical, and the result is the sym-
metry of the form of the funnel.

The Sound.—Its loudness was extreme, yet of such a
nature as to drown all other sounds without stunning. A
man could stand by his house, as it was shivered to pieces,
and not hear the noise of its breaking.

B. Whitaker heard it, together with others, at the dis-
tance of 60 miles. He says that even at that distance it
indicated great force. The barometric gradient inclined
from Mr. Whitaker to the tornado ; consequently the propa-
gation of the sound received no help from the wind. Thunder
has very seldom been heard at a greater distance than
to miles. The sound of the tornado was therefore thirty-six
times louder than the loudest thunder. Heavy cannonading
has been heard, it is said, at the distance of go miles, and
“the report of a volcano at St. Vincent was heard at Deme-
rara, 300 miles off.” The voice of the tornado is, therefore,
one of the strongest known to art or nature.

The Tornado in Illinois—The general appearance of the
tornado, as a whole, in Illinois, was somewhat different from
that which it presented in Iowa. ‘The ascending column of

¢
7

tata

1874.] The Iowa and Illinots Tornado. 393

air was no longer on one side of the centrifugal cloud, but
apparently near itscentre. Hence the witnesses generally
described the cloud as it approached, as consisting of a dark
cloud to the north-west, a less dark to the south-west, and a
clearer space between. In Iowa all circumstances had com-
bined in order to render precise observation easy. In
Illinois the very reverse was the case. I shall therefore
treat this portion of the subject in a few general remarks.

The tornado developed energy in this State quite as great
as that displayed in Iowa. Its direétion of revolution was
the same. The disposition of the ruins were precisely
similar. It showed the same and even a greater partiality
for water-courses, turning abruptly from its course in order
to follow them. Its direétion varied between north-east and
south-east, and was in the main easterly. At the moment
when its velocity diminished, and before reaching Spoon
River, it passed down close to the whirlwind, and even on
its very path a perfect cataract of water. The height of the
cloud must have been very great, for it was seen in the west
for hours previous to its advent. There was less hail, and
the sound was not so generally noticed as in Iowa.

The Identity of the Tornado in Iowa with that in Illinots.—
When lost track of, the Iowa tornado was close upon the
Iowa river, and travelling to the south-east. Its general
course had, however, been easterly. A very severe rain-
storm passed over the district between its point of dis-
appearance and the Mississippi River. ‘Trains were delayed
by it and bridges washed away. On the Mississippi itself
some damage was done to shipping by a violent gust of
wind, which accompanied the rain. At Monmouth there
was a severe thunderstorm. ‘Twenty miles to the south of
it the tornado again struck the ground. It was at Youngs-
town, at 5.45 P.M., or thereabout. From A. McKee’s house,
north of Washington, Iowa, to Youngstown, is a distance of
about 63 miles in a straight line. The tornado was at
McKee’s house at 3.10 P.M. The difference between
5.45 and 3.10 is 2.35. ‘The discrepancy due to longitude is
four minutes, very nearly. The time, therefore, consumed
by the storm in travelling from opposite Washington, Iowa,
to Youngstown, Illinois, was two hours thirty-one minutes,
or two and a-half hours. 63+24}=251, which is, therefore,
the velocity of the storm, in miles per hour, in a straight
line. The length of the journey was materially increased
by the crookedness of the path. This brings the velocity
nearly up to that with which the meteor traversed Keokuk
and Washington Counties, Iowa. These facts, taken in

394 The Iowa and Illinois Tornado. [July,

connection, irresistibly lead me to the conclusion that the
tornadoes in the two States are one and the same.

The point where the tornado first struck the ground on
South Skunk River is situated in 92° 20’ West Longitude and
41°15’ North Latitude. It was finally lost track of near Peoria,
in 89° 37’ West Longitude, and 40° 40’ North Latitude. The
whole motion of the tornado, therefore, was 2° 43’ east, and
35’ south, or 143 miles east, and 41 miles south. The mean
direction of its path was 24° 51’ south, and 65° g’ east, and
its whole motion 149 miles. The crookedness of its path
renders its actual motion considerably greater.

In a late communication Mr. B. Whitaker, correspondent
of the Smithsonian Institute of Warsaw and Illinois, states
that the elevation of the summit of the cloud was about 18’.

The author thanks Elias Colbert, of the Chicago ‘“‘Tribune,”
and the editors of the local newspapers at Washington and
Sigourney, Iowa, for assistance rendered, and especially for
publishing an extensive list of questions concerning the
tornado, which secured for him valuable information from
persons residing at a distance.

1874.] ( 395 )

NOTICES (\OF ._BOO KS.

An Elementary Treatise on Steam. By JoHN Perry, B.E.
London: Macmillan and Co. 1874.

Tus is unquestionably a very useful little text-book, but the
author has not altogether done himself full justice in its publi-
cation. In the first place the title is ill chosen, as it fails
to convey any adequate idea of the real nature of the work.
There is one good feature in this little volume which is not
generally to be found in publications of a similar character, and
this consists in a piecemeal treatment of the subject under con-
sideration; after which examples, or problems, are given, to be
worked out by the student in each branch, thus enabling him to
ascertain for certain that he has fully comprehended the rules
laid down in each case. Mr. Perry acknowledges having re-
ceived much assistance, in the compilation of this little book,
from the treatises of well-known authors in engineering science ;
but whilst he remarks—not perhaps without reason—on the
absence of ‘‘ experimental and other verification” of many of
Prof. Rankine’s calculations, there is nothing to show that he
has himself attempted any practical verification of them.

This work is divided under four headings, viz.—I. Heat, &c.
II. Steam-Engines and Boilers. III. Locomotives. IV. Marine
Engines. From the range of subjects thus attempted within
the compass of one small volume, it will at once be seen that
they can each only be briefly touched upon; and this will be
more apparent when it is stated that the important subjects of
*‘Combustion ” and “ Calorific Power” of Fuel together occupy
less than seven pages. In the chapters relating to different
kinds of engines, the oft-told tales of their early inventions are
again repeated, thus adding to the bulk of the volume without
much enhancing its value as a scientific work. In the chapter
relating to locomotives about eight pages are given to the
subject of ‘* Permanent Way, &c.,” which had better have been
left out altogether, as it is perfectly impossible to treat properly
so important a subject thus briefly. The information regarding
“Compound Engines” is scattered over six pages, in different
parts of the book. Now this is a subject which is second to
none other, when bearing on the question of the economical
working of steam-engines, and might well have filled several
pages, since to its introduction is due much of the saving of fuel
effected in recent steam-engine improvements.

We make these remarks with no wish to injure the reputation
of this work, but merely in order to point out where it may be
improved should it reach a second edition. On the whole it

396 . Notices of Books. [July,

appears to have been carefully compiled, and is furnished with a
useful Appendix of Tables and a good Index; and it will doubt-
less be found a valuable hand-book for students, to whom we can
commend it with confidence.

Our Ironclads and Merchant Ships. By Rear-Admiral E. Gar-
DINER FISHBOURNE, C.B. London: E. & F. N. Spon.
1874.

Tuis work is evidently intended as a reply to the principles of

Naval Construction as laid down in ‘“‘ Naval Science.” The

discussions and differences of opinion, which disclose themselves

from time to time in our daily and scientific journals, regarding
the modern type of war vessels, clearly show that there are two
sides to the question as to whether those recently constructed
have been built upon proper scientific principles. Now we know
that the designs of Mr. Froude and Mr. Reed have long pre-
vailed at the Admiralty, and the Schools of Naval Architecture
disseminate the rules laid down by these authorities. Against
the principles thus taught Admiral Fishbourne brings forward
strong arguments, based upon scientific reasonings, and until
his propositions are overthrown by still weightier arguments we
shall continue—as we always have done—to have but little faith
in the architects of a vessel that will flounder, as did the Captain,
or that require ‘‘ so much ballast to make them less dangerous,”
as the Sultan and Invincible. In consequence of Mr. Froude’s
propositions, deep empty spaces in the bottoms of ships were
introduced by Mr. Reed, ‘“‘ expressly to facilitate the raising the
engines, boilers, and other weights, because it has been ascer-
tained that the tendency of ships to roll has been reduced by
these means;”’ but, as is clearly shown by Admiral Fishbourne,
this caused the errors of calculation to be on the wnsafe side,—
that of decreasing the stability below the quantity assigned by
it. This principle of construction appears to us to be totally
opposed to all previously accepted means of ensuring stability,
as is practised, for instance, in the construction of a life-boat,
where the spaces are arranged on the sides and ends of the
vessel. To construct such deep hollow spaces at the bottom of
the vessel must tend to give that part of it increased buoyancy,
which, as we have already shown, has to be overcome by a heavy
amount of ballast, as would be the case if a boy covered the
bottom of his little yacht with cork. The plan adopted of cal-
culating a ship’s stability upon the metacentric method in a still
basin is justly condemned by our author as not enabling a safe
estimate to be made, ‘*‘ because a vessel, when in motion ahead,
possesses a greater total stability than her inclination indicates,
for it is necessary to provide for sufficient stability when a ship
is without motion ahead, and, therefore, without hydrodynamic

mera

1874.) Notices of Books. 397

stability,” and he carries his argument out fully to prove that the
present metacentric method of calculation is erroneous. The
question of buoyancy is next dealt with ina manner which leaves
Mr. Reed but little cause to be satisfied with his own perform-
ances. In our ironclads great buoyancy is given at the bottom
of the vessel, whilst the heavy armour plating on the sides gives
weight where buoyancy should exist, for it is at this very point
where the life-belt of the ship should be placed. But Admiral
Fishbourne is not content with merely stating his arguments at
length, but they are supported at length by mathematical calcu-
lations which leave no grounds for concluding otherwise than
that his theory is based upon true scientific principle.

Practical Solid or Descriptive Geometry. By W. TIMBRELL
Pierce, Architect, late Lecturer on Geometrical Drawing
at King’s College, London (vice Prof. Bradley), and Harrow
School. London: Longmans, Green, and Co. 1871.

Tuts is a work which has doubtless often been needed by the
student of practical solid Geometry. Although many excellent
works of this character exist in foreign languages, we have none
of a really useful character published in English. A thorough
knowledge of the principles of descriptive geometry is needed
by many professional men, to enable them to represent solid
objects on a plane surface, and hence its application to all the
arts of construction, such as architecture, engineering, fortifica-
tion, &c. To the artist, also, a knowledge of this subject is
most important, as enabling him to draw in true perspective,
cast the shadows of objects truly, and obtain the true position of
the locus of greatest light on an object.

The first part of this work treats on orthographic projection,
and is divided into six chapters as follows :—I. Definitions, &c. ;
Projections of Points and Lines. II. On Straight Lines and
Planes. III. The Five Regular Solids, viz., the Tetrahedron,
the Cube, the Octohedron, the Dodecahedron, and the Icosa-
hedron. IV. Consists of Examples and Problems illustrating the
principles of construction contained in the preceding chapters.
V. On Section Planes and the Intersections of Solids. VI. On
Tangent Planes and Surfaces in Contact.

The second part of the book is on Perspective, or Radial Pro-
jection, which is the application of the principles, enunciated in
the first part, to practice on a plane surface: their application to
the several arts of construction is a further development of the
subject, which Mr. Pierce promises to explain in a future work.
The careful manner in which the student is gradually advanced
from one point to another, through the pages of this book, must
render it one of great value to the student as a text-book, whilst

VOL. IV. (N.S.) 3E

398 Notices of Books. [July,

the manner in which it has been got up leaves nothing to be
desired: it is printed in a good bold type, and illustrated with
thirty-seven plates carefully drawn and clearly lettered.

Results of an Experimental Enquiry into the Mechanical Proper-
ties of Steel of Different Degrees of Hardness, and under
Various Conditions, Manufactured by Charles Aspelin, Esq.,
Westanfors and Fagersta Works, Sweden. By Davip
KirKALpy. London: published by the Author. 1873.

WirTuin the last few years a revolution has been gradually
effected in constructive art by the introduction of a material
which combines, in an eminent degree, strength, hardness,
and toughness, and which admits, according to its mode of
preparation, of great variations in its physical properties, and is
therefore applicable to a vast variety of purposes. As the appli-
cations of.steel are constantly being extended, it becomes a
matter of great importance to the mechanical, civil, and mining
engineer that the physical properties of the material should be
accurately determined. Few men are better qualified to conduct
such enquiries than is Mr. Kirkaldy. His great experience in
testing the mechanical properties of metals is the best guarantee
that his tests are judiciously applied, and the results intelligently
interpreted.

In the present work Mr. Kirkaldy gives*the results of an
elaborate enquiry into the physical characters of a large number
of samples of Swedish steel, made at Fagersta. Some of these
tested specimens were sent to the Paris Exhibition of 1867, but
the greater number were prepared for the late Vienna Exhibition.
The results exhibit the behaviour of the metal when subjected to
pulling, thrusting, bending, twisting, and shearing strains; in
fact, when tortured in every way that can possibly be of interest
to the engineer. These results are exhibited in a series of
carefully-arranged tables, which, although of great value for
reference, are not of course attractive to the reader. They
deserve, however, to be carefully studied by all who are interested
in the manufacture and applications of modern steel.

Annual Record of Science and Industry for 1873. Edited by
SPENCER F. Barrp. New York: Harper Brothers.

Tuis work, which has now reached its third year, is in its general
objects similar to the ‘‘ Year-Book of Facts.” It has, however,
certain unmistakable advantages over its English contemporary,
Its information is not drawn from ordinary newspapers.

1874.] Notices of Books. 399

The scientific and technological journals of France, Germany,
Holland, Switzerland, Italy, and Denmark, as well as of America
and England, have been carefully laid under contribution.
Hence paragraphs found in this volume may be quoted or ap-
pealed to with a reasonable amount of confidence. Another
useful feature is, that not merely the names of the journals
quoted are given, but the date and the page, so that it is easy to
verify any citation, or, in case of on abstract, to find full parti-
culars. That such an arrangement much enhances the value of
any work of this class is obvious. The classification is also
natural, or scientific, which is the same thing.

To an Englishman, perhaps the most interesting feature of the
book will be found in the notices of various American institutions
for the promotion of science. In this respect we cannot help
expressing the fear that America is evincing greater energy,
greater liberality, than ourselves. Of this we find many in-
stances. The museum at Yale College has secured the finest
specimen of the pterodactyl ever discovered. The British
Museum was negotiating for the purchase, but our rivals over
the Atlantic telegraphed to the owner to name his price, and
paid it. What have we in England equivalent to the Stevens
Institute of Technology at Hoboken, founded, it must be remem-
bered, by the munificence of a private individual? How few
instances do we hear in England of bequests or donations to
museums, free public libraries, and institutions for training up
discoverers and inventors! The liberality of our wealthy men
seems to take every channel rather than this. We do not at all
think that in natural aptitude for the successful study of
Science the British and Irish nations are inferior to any people
on the globe. But supremacy in this respect, just as in war,
can no longer be attained by the spontaneous and desultory
efforts of individuals. General, systematic, persistent action is
wanted. Original research has to be conducted on a changed
ground, and can no longer, as in the days of Scheele, or even of
Davy, be effected with a few phials, tobacco-pipes, gallipots, and
saucers. The influences which Decandolle finds most powerful
in ‘advancing science, by increasing the number of those who
prosecute it in the right spirit, are, first, a well-organised system
of instruction, independent of parties, tending to awaken research
and to assist young persons devoting themselves to science;
second, abundant and well-organised material means for scientific
work, libraries, observatories, laboratories, collections, &c. ; third,
freedom of utterance, and publication of any opinion on scientific
subjects without grave inconvenience.” To what extent are
these influences at work among us? We have museums; some
of them placed where they are accessible to few but fashionable
idlers ; others carefully closed in the evening, on public holidays,
and, in fact, at every time save what are called “hours of
business.”” We have libraries open to the same charges, whilst

400 Notices of Books. (July, —

the formation of establishments of this kind under Mr, Ewart’s
Act has been opposed—and in too many instances successfully—
by the interests now dominant in the House of Commons. Our
‘“system of instruction,” if “organised” at all, seems arranged
rather for the aggrandisement of parties and interests than for
training up thinkers and discoverers. Did not Lord Sandon, in
his place in Parliament, lately oppose a project for extending the

curriculum of elementary education, by asserting that the purpose —

of the movement was to ‘‘ crowd out” theological teaching? In-
stead of regaining the ground we have lost in competition with
foreign nations, it may be gravely questioned whether we are not
falling further and further into the rear. This is a melancholy
prospect for those who are aware of what is going on, and who

find their words of warning drowned amidst the uproar of the ~

‘‘ interests.”

Legal Responsibility in Old Age. By G. M. Bearp, A.M., M.D., —

New York: Russell.

THE title of this thoughtful, interesting work is far from con-
veying a full idea of its nature and contents. There is a very
common notion that the mind attains its maximum development
long after the maturity of the body; often, even, after the vigour
of the latter is plainly on the decline. Hence wisdom is regarded
as no less a normal attribute of old age than is strength of youth.
This view the author has subjected to a careful criticism, and, as

~

the conclusion of his researches, has pronounced it unwarranted ~

by facts. His method—the only one applicable in the case—has
been to prepare ‘‘a list embracing nearly all of the greatest
names of history whose lives are recorded in sufficient detail to
be of value in such an investigation,” and to note ‘‘the age at

which they did the original work by which they have gained their —

fame.” From a comparison of these data he has deduced ‘ the
period, the decade, and the year of maximum productiveness,
and the various grades between this and the period, the decade,
and the years of the least productiveness.” The enquiry has
been extended to great men of all departments, scientific, artistic,
and practical.

As a general result, the author finds that 70 per cent of the
work of the world is done before the age of 45, and 80 per cent
before that of 50. Going into more exact detail, Dr. Beard
divides the active portion of human life into six decades :—

The golden decade is between 30 and 4o.

The silver ‘s 40 and 50.
The brazen ,, e 20 and 30.
The iron si as 50 and 60.
The tin mn i 60 and 70.

The wooden __,, a 70 and 8o.

1874.) Notices of Books. 401

‘‘ The golden decade alone represents nearly one-third of the
work of the world, and nearly 25 per cent more dates than the
silver. The best period of fifteen years is between 30 and 45.
The advantage of the brazen over the iron decade is very striking,
and will cause surprise. There is considerably more work done
between 35 and 4o than between 40 and 45.” Dr. Beard, we
may observe, is not particularly happy in the selection of metals
to illustrate the comparative value of the respective decades of
life. Tin, for instance, may reach fifty times the value of iron.

It may be urged that many men of genius die young, and
that, possibly, if not thus prematurely cut off, they might have
continued to distinguish themselves up to an advanced time of
life. This objection the author anticipates by remarking that
“the average age of the great personages from whose lives the
law is derived is not far from 66 years.” He continues—‘‘ On
the average the last twenty years in the lives of original geniuses
are unproductive.” ‘‘ The broad fact, then, to which these sta-
tistics lead us is that the brain follows the same line of growth,
maturity, and decay as the rest of the body; that the nervous,
muscular, and osseous systems rise, remain, and fall together,
and that the received opinion that the mind—of which the brain
is the organ—developes and matures later than the power of
motion, or of physical labour and endurance, is not sustained by
the facts of history.”

Having thus stated his general conclusion, the author takes
into consideration qualifying circumstances and exceptions. He
points out the distinction between original work, requiring en-
thusiasm, and routine work, depending on experience. The
former he considers the especial province of the young, and the
latter of the old. ‘* The people unconsciously recognise this
distinction between the work that demands enthusiasm and that
which demands experience, for they prefer old doctors and law-
yers, while in the clerical profession—where success depends on
the ability to constantly originate and express thought—young
men are the more popular, and old men, even of great ability,
are shelved or neglected.” Here we may remark that in
England, and still more on the Continent, the clerical profession
is far from being the one from which originality of thought is
most urgently demanded. The faculty of expression often seems
to survive the power of origination. Thus the ‘old man elo-
quent” may often, in the evening of his days, embody in words
and give to the world the ideas which he had thought out in the
days of his prime. ‘The most marked exceptions to the law
are found in the realm of imagination; some of the greatest
poets, painters, and sculptors have done a part of their very best
work in advanced life.”” We might here, however, ask—whether
enthusiasm is not at least as necessary in the elaboration of an
epos, a drama, or a painting, as in that of a scientific theory or
a patent?

402 Notices of Books. [July,

The following passage is of profound significance :—‘‘ Children
born of parents one or both of whom are between 25 and 40 are,
on the average, stronger and smarter than those born of parents
one or both of whom are much younger or older than this.”
Political economists, we believe, claim the privilege of being
ignorant of every science except their own, and in virtue of that
ignorance they counsel late marriages, in the hope of checking
the too rapid increase of population. Unfortunately their scheme
reduces not merely the number, but the stamina, physical and
mental, of a nation.

Dr. Beard next examines the moral faculties, and finds them
subject to the same law. “It does not follow,” says he, ‘ that
when a man declines in moral principle that he necessarily be-
comes a horse-thief—a loss of active moral enthusiasm is fre-
quently all that is noticed.”” Among the causes of moral decline
in old age the author enumerates—‘‘ Over-exercise through life
of the lower at the expense of the higher nature; disease of the
brain, or of other parts of the body that react upon the brain,
and intellectual decline.” ‘‘ Death,’ he remarks, ‘‘is more fre-
quently a process than an event. When conscience is gone the
constitution may soon follow.” In illustration of the decline of
the moral faculties in old age, we are referred to the lives of a
number of historical characters, among whom figure the names
of Carlyle and Ruskin. A note on the death of Agassiz must
not be overlooked :—‘‘ To his friends it is well known that
Agassiz began to die several years ago. His death can be hardly
regarded as a loss to scientific research, for he had long ceased
to be productive. So far as he lives in the future of science, it
will be mainly for the original work that he did before he reached
his fortieth year. The intemperate manner of his opposition to
the theory of evolution, by which he was so rapidly winning
favour among the thoughtless and ignorant, and so rapidly losing
favour among the conscientious and scholarly, may find its par-
tial—if not complete—explanation in the exhausted condition of
his brain.”

We are here reminded of those changes of opinion on contro-
verted points—theological, political, or philosophical—which
eminent men sometimes experience in the decline of life. The
old friends of such a character seldom fail to denounce him as a
pervert and a renegade, and to accuse him of corrupt motives.
Those whom he has just joined hail him a convert, and rejoice
that his eyes have at last been opened to the truth. Both are
wrong. Such changes are often sincere, but they spring not
from illumination, but from a darkening of mental vision. The
accession of a man, once great, who has fallen into second
childhood, is no great triumph to any party. What matters it if,
in his declining years, Liebig showed leanings to Obscurantism ?
One of the most ordinary phases of mental decay is the mingled
incapacity and unwillingness to recognise new discoveries or new

1874.} Notices of Books. 403

ideas. We have seen it somewhere stated that no physician
who had reached the age of 50, at the time when Harvey made
public his discovery of the circulation of the blood, could ever be
induced to give it his recognition. Dr. Oliver Wendell Holmes,
one of the most original thinkers that America has produced,
says— New ideas build their nests in young brains; revolutions
are not made by men in spectacles, as I have heard it remarked ;
and the whisperings of new truths are not caught by those wha
begin to feel the need of an ear-trumpet.”

We have thus far expounded Dr. Beard’s opinions, and we
fully admit their value. The evidence he has brought forward to
prove that early life is the season for original work scarcely
admits of doubt; but we still question whether the development
and the decline of the various faculties of the human system are
so strictly synchronous as he maintains. We have known a man
of powerful frame and active habits, who, in the sixties, had be-
come quite childish, and ‘‘babbled o’ green fields” in a style
very unedifying; yet his pedestrian powers were the envy of
many men on the sunny side of 40. Conversely, our readers
will doubtless recall cases of men, physically feeble, but yet re-
taining their memory and their reasoning powers, little, if at all,
impaired. It seems to us that if any faculty is naturally strong,
and has been judiciously cultivated, it will preserve its vigour
after the system in other respects shows manifest symptoms of
decay.

Into the application of the doctrines above explained to foren-
sic medicine and to jurisprudence we do not propose to enter.
The author raises the questions—‘“ To what extent is the average
responsibility of men impaired by the change that the mental
faculties undergo in old age?”’ And—‘* How shall the effects of
age on the mental faculties be best brought to the attention of
our courts of justice?”’ That these questions will have to be
taken into account by the legislation of the future is undeniable.

The Year-Book of Facts in Science and Art. By Joun Timps.
London: Lockwood and Co.

Tuis annual still pursues the even tenour of its way, giving a
yearly summary of discoveries, inventions, and what are sup-
posed to be the most important facts connected with science and
industrial art. The utility of such a work is indisputable, and
that it meets a recognised want may be inferred from the fac
that it has regularly appeared for a quarter of a century. We
cannot, however, but regret that much matter is inserted on
authority which the scientific public can scarcely recognise. The
origin of many of the paragraphs and extracts is not stated,
whilst very many others are drawn from ordinary newspapers,
English and American. Now the inaccuracy of the scientific

404 Notices of Books. (July,

information given in such journals, from the ‘‘ Times” down-
wards, is a matter of notoriety. Indeed, strictly scientific
papers, English or foreign, appear to have been eschewed by the
editor. In the section on Chemistry, which extends to no more
than eleven pages, we find extracts from the ‘‘ Times” and the
‘‘Tilustrated London News,” but not a passage from Liebig’s
‘«¢Annalen,” from the ‘ Berichte” of the German Chemical
Society, or the ‘“‘ Chemical News.” A similar complaint might
be made concerning the chapters on Zoology and Botany, where
among the authorities figure the ‘‘ Homeward Mail, the ‘‘ Globe,”
the ‘‘ Pall Mall Gazette,” and the ‘‘ Grocer.”

As regards the classification of the matter, the editor appears
to proceed on principles of his own. Thus under the head
‘‘ Chemical Science,” we find paragraphs on ‘‘ Sunlight for the
Sick,” on ‘“‘ Prompt Remedies for Accidents and Poisons,” and
on “Opium Smoking in New York!” On the other hand,
‘Butter and its Adulterations” and “Tea and its Adulterations”
rank under ‘‘ Mechanical and Useful Arts.’’ On the other hand,
we find an article on ‘‘Compressed Peat’—abridged from the
‘‘Times ’—in the chapter on Geology and Mineralogy

But the gravest complaint against this ccEnpiGtieae is s the very
small amount of light which it throws upon the progress of the
sciences, and upon their practical and industrial applications.
An intelligent man, without any especial acquaintance with
chemistry, would, from merely reading Mr. Timbs’s “ Year-
Book,” be utterly unable to form any adequate idea of the part
which that science is now playing in the development of civilisa-
tion. We make these remarks not in a captious or ‘ hyper-
critical’’ spirit, but in the hope that the defects we point out
may be in future amended, and that the work may be made—
as it easily could—useful to the pubic, and a credit to our
technological literature.

The Treasury of Natural History ; or,a Popular Dictionary of
Zoology. By SaMuEL Maunper. Revised and Corrected,
with an Extra Supplement. By E. W. H. Hoitpswortn.
London: Longmans, Green, and Co.

Turis compact volume, as far as its size allows, gives a clear
and generally correct account of the orders, families, and genera,
as well as of the more important species of the animal world.
The illustrations are numerous. We do not agree with the
description given of the common viper. The ground colour of
the male is said to be a dirty yellow ; that of the female deeper.
Among the numbers we have seen the males were of a pale ash-
grey, and the females of a decided copper colour. We cannot
help expressing our dislike of the very minute type which has

1874.] Notices of Books. 405

been selected. Surely economy in cost and bulk is purchased
too dearly at the risk of impaired eyesight. The syllabus of
Practical Taxidermy will be found very useful to incipient
naturalists.

United States Commission on Fish and Fisheries. Commissioners’
Report, 1871-1872. The Fisheries of the South Coast of
New England. Washington: Government Printing Office.

THis is a most elaborate ‘‘ Blue Book,” extending to 850 pages,
and abundantly illustrated. The condition of American fisheries,
the arguments in favour of their regulation by law, the reports
of state commissions and of European authorities on this sub-
ject are given with great minuteness. We find also a description
of the various kinds of apparatus used in capturing fish on the
sea-coast and lakes of the United States, and of patents granted
to the end of 1872 for inventions relative to the capture, utilisa-
tion, or cultivation of fish and marine animals.

The greater part of the volume, however,—and this is a
feature to which we desire to call special attention,—is taken up
with matter specially interesting to the naturalist. There is a
report of Dr. Farlow on the sea-weeds of the south coast of
New England, and one by Mr. A. E. Verrill on the invertebrate
animals of Vineyard Sound and the adjacent waters, with an
account of the physical characters of the region. We must call
particular attention to the list of species found in the stomach
of fishes, as throwing a valuable light on their food, and to a
paper on the metamorphoses of the lobster and other crustaceans.
Mr. Theodore Gill’s catalogue of the fishes found on the east
coast of North America, and Mr. S. F. Baird’s list of fishes
collected at Wood’s Hole Harbour, with the table of tem-
peratures for the year 1873, also furnish valuable data for the
student of marine zoology. Very curious are the quaint re-
ports on the fauna, terrestrial as well as aquatic, of New
England and the other Atlantic Districts in the old colonial days.
A ‘‘squiril” is described as ‘‘ red, and he haunts our houses, and
will rob us of our Corne, but the Catt many times payes him the
price of his presumption.” Here is a hint which we commend
to the professors of cookery at South Kensington :—‘‘ We used
to qualifie a pickled Herrin by boiling of himin milk.” Scientific
controversy was, in those days, carried on with some disregard
of courtesy. ‘‘ One writes that the fat in the bone of a Basse’s
head is is braines, which is a lye.”

The whole volume is highly creditable to its compilers as well
as to the Government which has ordered its publication.

WOL. IV. (N:S.) 3F

( 406 ) (July,

PROGRESS IN SCIENCE.

MINING.

In consequence of the great development of the manufacture of spiegeleisen,
both in this country and on the Continent, the spathic iron ores, or native car-
bonates of iron, which are so largely used in this manufacture, have been
brought, within the last few years, very prominently into notice. A paper on
the distribution of these ores was read by Mr. C. Smith at the recent meeting
of the Iron and Steel Institute. In this country there are numerous deposits
of spathose ores, the most important perhaps being those of the Brendon
Hills, which are worked by the Ebbw Vale Company. Here the ores occur in
irregular veins, coursing through Devonian clay-slates, and recalling the con-
ditions under which similar ores occur in Rhenish Prussia. The spathic ores
of the Rhine Provinces are distributed in two separate distriéts—the one near
Coblenz, and the other to the east of Cologne; the latter being by far the
larger area, and containing the well-known Stahlberg. In Styria immense
deposits of spathic ores have long been worked, especially at the Eisenerz, for
the manufacture of charcoal-iron. Sweden seems to be destitute of these
ores, the magnificent iron-making resources of that country consisting mainly
of magnetites and red hematites. The mineral called Knebelite—a silicate of
iron and manganese—is worked in Sweden for use in the spiegeleisen manu-
facture.

Some deposits of tin-ore, which promise to become of enormous value, have
been discovered at Mount Bischoff, in Tasmania. We believe that Mr. Gould,
the Government geologist, who has recently returned from Tasmania, bringing
with him’ some fine examples of these ores, will shortly communicate a
description of the deposits to the Geological Society. Some of the tin-stuff
is associated with much ochreous oxide of iron. In addition to the lodes,
there are said to be alluvial deposits of vast magnitude. Mr. W. Ritchie
speaks of one bed of wash-dirt, 37 feet in thickness, rich in tin from the sur-
face to the bottom of the shaft.

A rapid tour through Gippsland, made in the early part of this year, has
enabled Mr. R. Brough Smyth to contribute to a recently-issued official Report
some remarks on the mineral resources of this part of the Colony of Victoria.
Many parts of the country are said to be rich in gold, but though some few
workings—such as the Walhalla mines—have been for some years in operation,
the gold-fields of Gippsland have yet to be developed.

From Persia we hear of recent discoveries of several beds of coal, and of
deposits of nickel ores, by Dr. Tietze, of Vienna, who is now engaged in ex-
ploring this country with special reference to its minerals. The coal is, said
to be of Mesozoic or Secondary age. Much of the coal of Queensland, and
valuable deposits of mineral fuel elsewhere, are also referable to the Mesozoic
period.

With reference to the age of some of the American coals and lignites,
Dr. J. S. Newberry has recently communicated to ‘ Silliman’s Journal” a
paper in which he takes a general review of the occurrence of coal in the Far
West, and seeks to show that the deposits of lignite and the various plant-beds
of the Western States are mostly of Cretaceous age, whilst some belong to the
miocene period. The coal of Vancouver’s Island is said to be Cretaceous.

A deposit of bismuth ore has been discovered near Meymac, in the Depart-
ment of the Corréze, in Central France. The ore occurs in a quartzose vein
running through granite, and is accompanied by wolfram, mispickel, and
pyrites. The bismuth exists chiefly as the native metal, but partly as sulphide
and as oxide.

epee

187 4.] Metallurgy. 407

The first volume of the “ Transactions of the American Institute of Mining
Engineers” has been recently published in Philadelphia. This volume con-
tains a rich collection of papers on mining and metallurgy, selected from com-
munications made to the Institute since its foundation in 1871.

METALLURGY.

No one will be disposed to question the good sense of the governing body
of the Iron and Steel Institute in awarding the first Bessemer medal to Mr. I.
Lowthian Bell, as a fit recognition of his services to the science and pra¢tice
of iron-smelting.

In delivering the Presidential Address at the recent meeting of the Institute,
Mr. Bell referred to the advance of mechanical puddling in this country, at the
same time expressing his fear that at present the success of Danks’s system
had hardly been found equal to what might have been expected from the Report
of the Commissioners appointed by the Institute to examine ifto the working
of this system in America. Danks’s furnaces have now been erected by
Messrs. Bolchow and Vaughan, Messrs. Hopkins, Gilkes, and Co., the Erimus °
Iron Company, and the North of England Industrial Iron Company, whilst in
North Statfordshire they have been introduced by Mr. R. Heath. It is there-
fore to be expected that we may soon have opportunity of thoroughly testing
the practical value of this system of puddling. Mr. J. A. Jonesywho has had
perhaps more experience than any one else on this subject, contends that the
Danks principle is perfectly sound, and merely requires development, and per-
haps a little mechanical modification, to make it commercially a success. He
maintains, indeed, that a few months hence we shall be able to turn out better
bars, cheaper by the rotatory furnace than by the old method of manipulation.
It has been said that the Danks furnace is, trom a mechanical point of view, a
complete failure, but the details of construction may be easily modified without
affecting the general principle. At the Erimus Works a furnace is to be
erected which will combine some of the principles of the Danks with those of
the Crompton furnace. Mr. Crompton’s furnace, in which finely-divided fuel
is introduced with the blast, has been working with great success at
Woolwich.

A mechanical puddling-furnace of peculiar construction, devised by M. Per-
not, has been worked by MM. Petin and Gaudet, at St. Charmond. The
puddler is an iron bowl, mounted on a cast-iron carriage, which is caused to
rotate by machinery. The bloom may be divided into as many portions as
may be desired, instead of being limited to a single large ball. The iron is
said to be of high quality, while the mechanical arrangements admit of being
applied to existing plant.

Spiegeleisen formed the subje& of an interesting paper communicated to the
Iron and Steel Institute by Mr. G. J. Snelus. This paper was intended to
supplement Mr. Forbes’s valuable “ Report on the Manufacture of Spiegeleisen
on the Continent,” published some time ago in the Journal of the Institute.
The use of spiegeleisen, originally suggested by Mr. Mushet, was worked out
by Mr. Bessemer, and its manufacture has now become an important branch of
manufadture even in this country. Instead of relying for our supply, as for-
merly, upon the Continent, we have found ores suitable for its production, and
have established its manufacture at Ebbw Vale, at the Landore Steel Works,
at Dowlais, at Middlesbro’, at Sheffield, and in Cumberland.

Attention has been recently called to the part which silicon plays in pig-iron
during its conversion in the Bessemer process. By oxidation in the converter,
the silicon is converted into silica, which passes into the slag, and during this
oxidation a much greater quantity of heat is evolved than could be obtained
by the oxidation of an equal weight of carbon. According to the experiments
of Troost and Hautefeuille, the carbon of cast-iron, at a temperature above
that of the fusion of the metal, reduces silica, the silicon replacing the carbon
in the pig.

y

408 Progress in Science. (July,

Some experiments have been made by Mr. C. H. Morton on the condition
in which silicon exists in pig-iron. The experiments were made on a No. 1
Bessemer pig, containing 4°612 per cent of silicon. They tended to show that
the silicon does not exist in a free state mechanically associated with the iron,
but rather in a combined form as a definite silicide of iron, just as carbon may
exist as a carbide; the silicon does not appear, however, to assume a gra-
phitoidal form in the iron, corresponding with the uncombined carbon of
cast-iron.

In recently describing a mass of meteoric iron from Howard Co., Indiana,
Dr. J. Lawrence Smith takes occasion to make some general remarks on iron,
which are not without interest to the metallurgist. The Indiana iron appears
to be a true meteorite; it contains 12°29 per cent of nickel, 0°65 of cobalt, and
0°02 of phosphorus; yet when a polished face is acted on by acids it does not
exhibit the well-known Widmannstittian figures. Some authorities have
maintained that these markings result from the accumulation of an alloy
richer in nickel shan the mass of the iron; whilst others have referred them
to a definite phosphide of iron and nickel, accumulated along certain lines of
crystallisation. Neither of these theories, however, satisfactorily accounts for
their presence in some irons and their absence fromothers. Dr. Smith believes
that in the solidification and crystallisation of iron there is a tendency to
eliminate the foreign constituents to the exterior of the crystals. If, then, a
meteoric mass has consolidated rapidly, the phosphorus might be so diffused
as to afford no marked indication of its presence, but if consolidated slowly
there would be a more or less perfect elimination of the phosphorus in parts
representing spaces between the crystals of the mass. We may remark, in
passing, that Dr. Smith has found that the presence of 1 per cent of phos-
phorus, or less, in cast-iron, enables the metal to resist the action of concen-
trated sulphuric acid to a greater degree than when the metal is entirely free
from phosphorus.

Natro-metallurgy is a term applied to a process for refining impure lead, re-
cently introduced by MM. Payen and Roux, of Marseilles. The foreign metals
present in the hard lead are removed by means of molten caustic soda, the
oxidation being facilitated by the introduction of jets of steam, a blast of air,
or addition of nitrate of soda.

Some notes on the metallurgy of bismuth have been communicated to the
‘‘Annales de Chimie” by M. A. Valenciennes, who describes the process
which he has introduced at St. Denis for working the Bolivian ores. Having
been first roasted in a reverberatory furnace, the ore is mixed with 3 per cent
of charcoal and a flux composed of lime, soda, and fluor-spar. After reduction
the products separate in order of density—at bottom a button of bismuth,
above this a regulus of sulphides of bismuth and copper, and on the top a
vitreous slag containing silicate of iron. The crude bismuth contains about
2 per cent of antimony and lead, and about the same proportion of copper,
with traces of silver. If used for preparation of subnitrate, the bismuth is
fused with nitre, to oxidise the antimony, whilst the other foreign metals are
separated by the wet way. The regulus may be roasted, and subjected to
similar treatment as the original ore. In treating the French bismuth-ores
recently discovered at Meymac recourse is had to a wet process. The finely-
divided ore is digested in hydrochloric acid, the solution neutralised, and water
added, whereby a subchloride is precipitated, and this precipitate is then
reduced by contact with metallic iron. The bismuth thus obtained is dried,
and fused with an alkaline flux. A similar mode of treating the French ores
has been carried out by M. Carnot. :

Dr. Laspeyres, of Aix-la-Chapelle, has contributed to the ‘ Journal fur
Praktische Chemie” a description of some artificial crystals of metallic anti-
mony, accidentally obtained in slags at the Miinsterbusch Lead-Works, near
Stolberg. Some antimonial residues and lead slags were smelted in a blast-
furnace, with the view of obtaining a hard lead rich in antimony. The crystals
appear at first sight to be regular cubes, resembling the well-known artificial
galena, but are really rhombohedra of nearly go°, combined with the basal

1874.] Mineralogy. 409

planes, and in some cases twinned so as to exhibit the characteristic re-entering
angles.

MINERALOGY.

A mineralogical paper of considerable interest has been communicated to
the American Academy of Arts and sciences by Prof. J. P. Cooke, jun., in
which he reviews the history of those micaceous minerals which may be
grouped together under the general name of Vermiculite. This name was
originally applied by Mr. T. H. Webb to a peculiar mineral which at the time
of its discovery excited much interest by its curious behaviour when heated ;
the substance exfoliated prodigiously, and the little scales opened out in worm-
like threads, which suggested the original name. This remarkable exfoliation
and the apparent increase in volume are referred by Prof. Cooke to the loss
of water of crystallisation, and may be compared with the well-known
efflorescent phenomena presented by the dehydration of certain crystalline
salts. Other minerals possessing similar pyrognostic characters have since
been discovered, and a comparison of these minerals has led the author to
extend the use of Vermiculite as a family name. Three distin species are
now included in this group: first, ¥efferisite, a mineral discovered by Mr. W.
Jefferis at West Chester, Pa., and described by Prof. Brush; secondly,
Hallite, a new species founded by Prof. Cooke on specimens collected by Mr.
J. Hall at East Nottingham, Chester Co., Pa.; and thirdly, Culsageeite,
another new species discovered in Col. Jenks’s Culsagee Mine in North
Carolina, which mine has yielded the remarkable specimens of corundum
noticed in our report last quarter. Prof. Cooke discusses in much detail the
crystallographic, optical, and chemical characters of Jefferisite, Hallite, and
Culsageeite, with special reference to their relation to the group of micas.

Our knowledge of the mineralogy of the Argentine Republic is much in-
creased by a paper recently communicated to Tschermak’s ‘* Mineralogische
Mittheilungen”’ by Dr. A. Stelzner, who was appointed a few years ago
Professor of Mineralogy in the University of Cordoba. The Sierra of Cordoba,
rising like an island from the surrounding pampas, is composed of three
parallel ridges, which consist principally of crystalline slates associated with
masses of granite in which are large quartz-stocks containing minerals of
considerable interest. Although consisting chiefly of quartz, these stocks
invariably contain mica, as well as large crystals of orthoclase-felspar.
Beryl is also found in six-sided prisms of unusual size, whilst apatite and
triplite occur subordinately. But the most interesting of this group is the
rare mineral columbite, specimens of which have been analysed in Cordoba
by Dr. Siewert. Another series of minerals described by Stelzner occurs in
crystalline limestones, associated with the metamorphic rocks of the Sierra.

Prof. A. H. Church has communicated to the ‘‘ Chemical News” his
analysis of Ashantee gold. Those who are familar with the fine collection of
nuggets and ornamental objects lately exhibited by Messrs. Garrard will
remember that most of the specimens presented a rich colour, heightened by
association with a red ferruginous earth, more or less adherent to the surface.
Church’s analysis gave—Gold, go°055 ; silver, 9'°940; iron and copper, traces.

The same chemist has also published in the ‘‘ Chemical News ”’ his analysis
of some clean grain-gold from a burn at Wanlock-head in Dumfriesshire. A
good deal of historical interest clings to the gold-fields of Southern Scotland,
though well-nigh forgotten at the present day. Worked by Sir Bevis Bulmer
in the sixteenth century, they yielded the gold from which the unicorns and
the bonnet-pieces of James IV. and V. were coined. It was these mines,
too, that were at one time to be worked by a company of twenty-four gentle-
men to be created “* Knights of the Gold Mines.” At present, however, the
Clydesdale washings yield only specimens for the cabinets of the curious.
Prof. Church finds the Wanlock-head gold to contain—Gold, 86:60; silver,
12°39; iron, 0°35. A specimen of Sutherlandshire gold has yielded to Mr. G.
H. Makins 79°22 per cent of gold and 20°78 per cent of silver. Pliny tells
us that when the proportion of silver in gold exceds one-fifth, the substance is

410 Progress in Science. (July,

called electyum. According, then, to this definition, which is still adhered to
by some mineralogists, the Sutherland gold is an electrum.

Two specimens of what appeared to be native silver have been analysed by
Prof. Church, and the results published in the ‘*‘ Chemical News.’ Both came
from Allemont, in Dauphiny, and were formerly in Heuland’s collection. One
contained—Silver, 71°69; mercury, 26°15; antimony and traces of arsenic,
2°16. The other contained—Silver, 73°39; mercury, 18°34; antimony and
arsenic, 8°27. These figures do not correspond precisely with analyses of any
native amalgams, nor with the antimonial silvers called dyscrasite, the latter
being always regarded as non-mercurial.

Although the Jubilee volume of ‘ Poggendorff’s Annalen,” which has
recently been issued in commemoration of the fiftieth year of its publication,
is for the most part devoted to memoirs on the several branches of physical
science, it is nevertheless of considerable interest to the mineralogist. Prof.
Rammelsberg gives a masterly sketch of the history of the Chemistry of Minerals
during the last half century: Vom Rath publishes some valuable crystallo-
graphic studies; and Hankel gives a resumé of his researches on the pyro-
electricity of certain minerals. In the same volume Dr. T. Scheerer has a
paper ‘‘On the Formation of the Minerals which accompany Ores.”’ His in-
vestigations relate to the conditions under which the most common non-
metallic minerals of lodes—calc-spar, quartz, barytes, and fluor-spar—have
been produced. As these may be formed in the wet way, and have probably
been so formed in nature, it is only rational to conclude that the ores which
accompany them in mineral veins owe their genesis to similar causes.

Two kinds of pseudomorphs after rock-salt have been discovered in sinking
shafts for working some deposits of salt at Westeregeln, near Stassfurt, in
Prussia. In one case we have a curious example of rock-salt pseudomorphous
after rock-salt, whose formation may be thus explained: chloride of sodium
was originally crystallised in cubic forms in a matrix of soft clay; the crystals
were then dissolved, leaving cubic cavities, which were afterwards more or
less distorted by movement of the surrounding clay; the walls of the cavities
were next lined by a thin coating of quartz-crystals; and, finally, the drusy
cavities became occupied by a second deposit of salt, which thus assumes
abnormal forms and presents the curious feature of cleavage not necessarily
parallel to faces of the crystal, since the internal stru€ture bears no relation
to external form. :

The other Westeregeln pseudomorphs are six-sided crystals, like those of
carnallite, but composed almost exclusively of chloride of sodium. Both
kinds may be found in the same hand-specimen.

Under the name of Rhagite, Prof. Weisbach has recently described a
hydrous arsenate of bismuth, discovered among the new uranium ores at
Schneeberg, in Saxony. The name was suggested by the botryoidal form and
grape-green colour of the mineral.

A description of a new Mexican mineral has been communicated by Don
Ant. del Castillo to the Journal ‘‘ La Naturaleza.”” The mineral is said to be
a double selenide of bismuth and zinc.

The name of Huantajayite has been bestowed upon a Peruvian mineral by
M. Raymondi, of Lima. Its composition seems peculiar; it is said to be
a double chloride of sodium and silver, containing 89 per cent of the former
and 11 of the latter salt. It occurs in small colourless cubes, associated with
the chloride and chloro-bromide of silver and oxychloride of copper. This
occurrence would seem to show that the metallic chlorides and bromides in
Peru may owe their origin to the action of sea-water on the minerals of the
lodes.

Grochauite is the name which Dr. Websky proposes for a new species
closely related to clinochlore, occurring in serpentine at Grochau in Silesia. It
is associated with an ore of chromium described by Dr. Bock as Magno-
chromite, which appears to be a member of the spinel group, rich in magnesia.

1874.] Engineering. AIL

Websky has recently analysed the mineral called Strigovite, which occurs in
granite at Striegan in Silesia.

A mineral resembling chalcomorphite has been found in limestone enclosed
in the lavas of Ettringen, near the Lake of Laach, and has been recently
described by Herr J. Lehmann as Ettringite.

The extremely rare mineral Osm-iridium, an alloy of osmium and iridium,
has been discovered in small quantity near Stockyard Creek, Gippsland, in the
Colony of Victoria.

Prof. Rammelsberg has communicated to the German Geological Society,
at Berlin, several new analyses of Idocrase, or Vesuvian, accompanied by a
review of our knowledge of the chemical composition of this species.

Some notable examples of the occurrence of crystals of quartz have been
collected by Dr. Websky, and described in a crystallographic paper published
in Leonhard and Bronn’s * Jahrbuch.”

ENGINEERING—CIVIL AND MECHANICAL.

Guns.—A paper of some importance at the present time, when the size of
guns is growing so rapidly, was recently read before the Institution of Civil
Engineers, by Mr. G. W. Rendel, on ‘ Gun-Carriages, and Mechanical
Appliances for Working Heavy Ordnance.’ Owing to the increase in the
power and size of ordnance since the introduction of armour, gun-carriages
have gradually become elaborate machines, and the appliances for working the
monster ordnance now in contemplation will tax all the resources of mechanical
science. The first difficulty experienced in mounting the Armstrong rifled
guns arose from the much greater violence of their recoil as compared with
that of the old cast-iron guns, a disadvantage mainly resulting from their
superiority in lightness, strength for strength. After describing a self-acting
brake for arresting recoil, designed and successfully tried at Elswick in 1864,
reference was made to the great superiority of wrought-iron over timber as a
material for gun-carriages, and experiments made in 1865 were cited as showing
the error of the popular objection entertained against wrought-iron on the score
of its producing, when struck by shot, more numerous and destru¢tive splinters
than timber. By the adoption of mechanical arrangements for the application
of manual power to the working of ordnance, guns up to 25 tons weight can
now be worked with more ease, safety, and rapidity than guns of a fifth of that
weight were formerly worked. Guns, however, are now being made of nearly
double that weight, and hence the adoption of some inanimate power, in the
place of mere hand labour, for loading and working heavy ordnance, has become
an absolute necessity for guns of the future. The simplicity and compactness
of hydraulic machinery, and the perfea control it gives over heavy weights,
especially adapts it for the purpose. Hydraulic power sufficient for the
heaviest gun may be transmitted through a very small tube for long distances
and by intricate ways, so that a steam-pumping engine may be placed in a
fort or ship in such a position as to be absolutely secure, and supply power by
this means for working many guns. The arrangements for loading and working
guns by hydraulic machinery embrace a new system of mounting turret-guns,
in which the carriage is dispensed with, and the gun is supported on three
points, viz., on a pair of trunnions placed well forward, and on a saddle under
the breech itself. The trunnion-arms rest in two sliding-blocks, which run in
guides on fixed beams, built on the floor of the turret; and immediately behind
each block, in the direct line of recoil, are two hydraulic cylinders for checking
recoil and running the gun in or out, whilst the saddle which supports the
breech slides along a beam or table beneath it. The front of the beam can be
raised or lowered by a hydraulic press to give any desired elevation, but the
rear is pivoted at a point corresponding to the horizontal position of the gun;
consequently it always returns to the horizontal position as it recoils, whatever
elevation it may be fired with, clearing the port in coming back. Thus the
advantage of muzzle-pivoting, viz., the reduction of the size of port-holes, is

412 Progress in Science. (July,

to a large extent realised, without the necessity of lifting or lowering the gun
itself.

Ships.—At the recent meetings at the Institution of Naval Architects, several
very important papers were read relating to the form, size, and construction of
ships. An examination of these in detail would occupy more space than we
can now give to the subject, and we shall therefore do little more than name
the several principal features of these papers. The prominent position which
the question of the proper loading of mercantile vessels has lately assumed,
has induced Mr. Benjamin Martell, Chief Surveyor of Lloyd’s Registry of
British and Foreign Shinping, to investigate the question as to what constitutes
a fair freeboard for sea-going vessels, and he has accordingly prepared a scheme
of freeboard for the various types of vessels in existence. A set of tables has
now been published which determine, not a hard and fast load-line, which
would be impracticable, but a fair line of reference for ordinary trades for the
various types of sea-going sailing vessels and steamers of the first class. The
principle governing this load-line is that of allowing acertain proportion of the
total volume of the vessel above the water, in relation to her size and extreme
length, and the mode adopted for cutting off this percentage of spare buoyancy
is by multiplying the registered tonnage under deck by roo, and dividing this
by the produé of the length, breadth, and depth of the vessel. The quotient
obtained affords a fair approximation to their relative fineness, from which the
proper freeboard may be readily traced on the tables.

Mr. W. John’s paper on the “ Strength of Iron Ships” produces some faéts
which are sufficient to cause serious alarm, and ought, as he suggested, to
secure a very careful consideration of the subject. He remarked, with regard
to the constant tendency to increase the size of vessels, that, although it may
not astonish anyone to hear that vessels over 300 feet in length are not as a
rule strong enough to bear being pivoted on a rock or causeway amidships, it
will probably surprise some to learn that they are liable to a strain of 8 tons
per square inch afloat. ‘‘ This,” he states, “‘ with the present state of the iron
manufacture, gives a factor of safety of not more than 23, which would scarcely
be considered satisfactory by engineers for a land structure.”

This paper was followed by one by Mr. W. Froude, F.R.S., Vice-President,
on the “ Useful Displacement as Limited by Weight of Structure and of Pro-
pulsive Power,” in which it was remarked that the existing tendency towards
extreme length, as compared with midship section, was only justified where
extreme speed was required,—speed very much greater than that which sea-
going merchant ships in fact realise. He drew a conclusion from prior argu-
ments that the total sectional areas of the deck, the bottom, and the sides of a
ship must be proportioned to the stress; and, as the structural weight may be
taken as proportioned to their sectional areas multiplied by the ship’s length,
it must be regarded as proportional directly to the fourth power of the length,
dire@ly to the breadth, and inversely to the depth. From this follows the
remarkable result that, alike whether we enlarge a ship by increasing her three
dimensions throughout in the same given ratio, so as to enlarge her total dis-
placement in the cube of that ratio, or whether we enlarge her by increasing
her length alone, the increased structural weight will be as the fourth power
of the enlargement of dimensions. It is obvious that in whatever degree the
total dead weight of a ship’s hull depends on her requirement of structural
strength, this conclusion tells most unfavourably on the useful displacement
of a ship enlarged simply by elongation, as compared with one enlarged in all
her dimensions alike.

Mr. Nathaniel Barnaby, Vice-President, in a paper ‘‘On some Recent
Designs for Ships of War for the British Navy, Armoured and Unarmoured,”
entered into particulars of size, form, and construcive details which could not
well be given in a condensed form.

Some very interesting experiments for the determination of the resistance
of a full-sized ship, at various speeds, by trials with H.M.S. Greyhound, were
recently instituted by the Admiralty. The conclusion of these experiments
was, that a comparison between the indicated horse-power of the Greyhound,
when on her steam trials, and resistance of the ship, as determined by the

1874.] Engineering. 413

dynamometer, showed that, making allowance for the slip of the screw, which
is a legitimate expenditure of power, only about 45 per cent of the power
exerted by the steam is usefully employed in propelling the ship, and that no
less than 55 per cent is wasted in friction of engines and screw, and in the

detrimental reaction of the propeller on the stream-lines of the water closing
in around the stern of the vessel.

Railways.—The numerous railway accidents which have taken place of late
have necessarily direGted the attention of engineers and others interested in
the working of railways to the question as to how accidents may be avoided,
or, at least, lessened. This subje& has been taken up by Captain Tyler, who
recently read a paper before the Society of Arts on the ** Working of Railways,”
and on simplicity as the essential element of safety and efficiency in the
working of railways. From this paper we learn that the various classes of
collision, and the accidents at facing-points, may together be roughly stated
to comprise from two-thirds to three-fourths of the more serious casualties to
railway trains. Railway working, which was at first easily condudted, is
becoming a science with its separate branches, and deserves, therefore, care-
ful study and investigation. Questions as to the arrangement ard working of
points and signals, and as to preserving intervals of time and space between
trains and their accessories, enter more or less into the causes of the majority
of railway accidents.

With regard to signals, by the application of locking and other apparatus
it is possible to prevent nearly all those accidents which occur in consequence
of any mistake of the signalman. Confli@ between signals, and confli@
between points and signals, may alike be avoided, and a good combination of
locking, bar and bolt, may be made to ensure that the facing-points are com-
pletely over before the proper signal is lowered, and may also prevent them
from being moved during the passage ofa train. As regards signalmen, the
selection and regular training of fit men for the performance of such duties as
they have to perform; the employment of responsible inspectors for constant
supervision, and the preservation of rigid discipline; the command of a
sufficient number of relieving men to take Sunday duty and to replace signal-
men absent from sickness or otherwise, and the maintenance in high condition
of the whole of the apparatus, are matters of obvious importance; but
experience has shown that it is by no means unnecessary to refer to them.
By attention to these considerations, the dangers of facing-points are for the
most part obviated, and engines and trains may be turned in and out, and
across one another, with marvellous rapidity and facility, and in a way that
would be otherwise impossible.

The next branch of the subje& is that which refers to the preservation of
intervals between trains; and this is best done by what is known as the block
system. There are many descriptions of instruments for working the block
system, and various rules and regulations applicable to it on different lines of
railway. The main principle involved is, simply, by the division of a line into
block sections, and by allowing no engine or train to enter a block section until
the previous engine has quitted it, to preserve an absolute interval of space
between engines and trains.

To sum up the whole case, it is necessary, in railway working, to deal with
men and mechanism. Men are fallible, and mechanism may fail. The com-
plications of railway construction and traffic have increased enormously, and
are still increasing. At some points, the lines, the sidings, and the crossings
are so numerous, and the traffic is so constant, that the employment of the
best means and appliances is unavoidable. In other localities, of severe
gradients or obstructed view, or when greater danger is otherwise incurred,
similar means and appliances are also indispensable. These points and
localities become more and more numerous, and ample experience has now
been obtained as to the most efficient modes of working. The result of that
experience has plainly demonstrated that mistakes and accidents may best be
avoided, and efficiency of working may best be attained—(1) By judicious

VOL. IV. (N.S.) eG

414 Progress in Sctence. [July,

selection and careful training of the men employed, and especially, in a safety
point of view, of engine-drivers and signalmen ; (2) by providing those men
with reasonable and necessary apparatus and accommodation for the proper
performance of their duties ; (3) by maintaining good discipline amongst
them, which is only feasible when proper means and accommodation are
provided, when proper modes of working are adopted, and when it is possible
for them to carry out in praétice the rules and regulations furnished for their
guidance.

Dire@ly bearing upon this subject, also, were two papers read before the
Institution of Civil Engineers, the one, ‘‘ Safety of Permanent Way,” by C. P.
Sandberg, and the other on “ Railway Fixed Signals,” by R. C. Rapier. We
can now only briefly refer to these two papers. In the former one, the prin-
cipal object the author had in view was to draw attention to the weakening of
rails caused by punching or notching. In the latter, attention was chiefly
given to the interlocking and block system, and a tabular statement exhibited
showed that, by introducing this system on fourteen of the principal railways,
by an expenditure of } per cent on the whole cost of the railways, their
carrying power might be so increased that three times as many trains could
be run on the block system as without it, and with greater safety.

Rock-Drilling.—With the ever-continuing increase in the progress of mining
industries, the question of rock-drilling is gradually attaining an importance
second to few others conneéted with the leading industries of the world. A
paper on the subje@ of * Rock-Drilling Plant in its most Recent Modifica-
tions,’”’ was recently read before the Institution of Mechanical Engineers by
Mr. T. B. Jordan, the principal obje@ of which was to dire@& attention to the
Darlington rock-drill, in which most of the defects of other drills were avoided.
In this drill all the numerous small parts are omitted, and a machine has
been produced that will make from 100 to 1ooo blows per minute under a
pressure of from 4o to 50 lbs. per inch. Only two parts are used to produce
the percussive action of the machine—one fixed, and the other moving. The
cylinder and cover may be considered as the fixed part, and the piston and
rod—which are forged solid—as the moving part; and these are all that are
required to produce the reciprocating action of the machine. The rotation of
the tool is obtained by a rifled bar, which is fitted with a ratchet-wheel
recessed into the caver of the cylinder. There is no automatic action for
advancing the drill to follow up the work, the reason assigned for its absence
being that experience has shown that the advantage gained by an automatic
arrangement was by no means an equivalent for the extra trouble and
expense they entailed.

A new rock-drill, which has for some time past been worked successfully
in the United States, has recently been introduced into this country. It is
the invention of Mr. Ingersoll, and the main points which constitute its
novelty are the giving a rotary motion to a piston—either steam- or air-
moved—and conveying that motion to the drill by means of a spiral rod
connected to the piston. This rod has an adjustment, so that, when desired,
the piston may work direct in one direction and be made to rotate in another.
There is also an arrangement of tappets, by which the piston is forced
slightly back just before the drill strikes the rock. A cushion is thus formed,
which prevents the piston striking the end of the cylinder, and the shock of
impact is received only by the drill-piece, and is not communicated to the
other parts of the apparatus. The feed-motion of the drill is also governed by
a tappet, which is struck by the piston in its forward stroke, and as the drill
progresses into the rock.

GEOLOGY.

Physical Geology.—Mr. J. F. Campbell, in a paper on ‘ Polar Glaciation,”
read before the Geological Society, described his observations made during
thirty-three years, and especially those of last summer, when he travelled
from England past the North Cape to Archangel, and thence by land to the

1874.] Geology. 415

Caucasus, Crimea, Greece, and the South of Europe. In advancing south-
wards through Russia a range of low drift hills occurs about 60° N. lat., which
may perhaps form part of a circular terminal moraine left by a retreating polar
ice-cap ; large grooved and polished stones of northern origin reach 55° N. lat.
at Nijni Novgorod, but further east and south no such stones could be seen.
The highest drift beds along the whole course of the Volga seem to have been
arranged by water moving southwards. In America northern boulders are lost
about 39°, in Germany about 55°, and in Eastern Russia about 56° N. lat.,
where the trains end, and fine gravel and sand cover the solid rocks. Ice-
action, in the form either of glaciers or of icebergs, is necessary to account for
the transport of large stones over the plains, and the action of moving water
to account for drift carried further south. There are no indications of a conti-
nuous solid ice-cap following southward over plains in Europe and America
to, or nearly to, the Equator; but a great deal was to be found on shore to
prove ancient ocean circulation of equatorial and polar currents, like those
which now move in the Atlantic, and much to prove the former existence of
very large local ice-systems in places where no glaciers now exist.

Prof. Ramsay, in discussing the physical history of the Rhine Valley, stated
his opinion that, during portions of the Miocene epoch, the drainage through
the great valley between the Schwarzwald and the Vosges ran from the
Devonian hills north of Mainz into the area now occupied by the miocene
rocks of Switzerland. Then, after the physical disturbances which closed the
Miocene epoch in these regions, the direction of the drainage was reversed, so
that, after passing through the hill country between the Lake of Constance
and Basle, the river flowed along an elevated plain formed of miocene depo-
sits, the remains of which still exist at the sides of the valley between Basle
and Mainz. At the same time the Rhine flowed in a minor valley through the
upland country formed of Devonian rocks, which now constitute the Taunus,
the Hundsruck, and the highland lying towards Bonn, and by the ordinary
erosive action of the great river the gorge was gradually formed and deepened
to its present level. In proportion as the gorge deepened, the marly flat mio-
cene strata of the area between Mainz and Basle were also in great part worn
away, leaving the existing plain, which presents a deceptive appearance of
having once been occupied by a great lake.

Pale@ontology.—A new genus of corals has been founded by Dr. Nicholson,
under the name of Duncanella, in compliment to Prof. Duncan, of King’s
College. The specimens of this coral have been found in the Lower Silurian
rocks of Indiana.

Mr. L. C. Miall, Curator of the Museum of the Leeds Philosophical Society,
has published an excellent guide to the Fossil Collection in the Museum, which
is in itself a capital elementary introduction to Palzontological Science: the
principal groups of fossils, both plants and animals, are described, and their
modes of preservation are pointed out, whilst numerous references are given
to works which would prove useful to the student.

Mr. Seeley has recently described a new genus of Plesiosaurians from the
Oxford Clay, which he has named Mur@onsaurus.

A new family of Paleozoic Brachiopoda has been established by Mr. David-
son and Dr. King, which they call the Trimerellide. As far as is at present
known they are confined to the Cambro-Silurian and Silurian systems.

Sub-Wealden Exploration.—A total depth of 671 feet has now been reached,
and the boring is still in the Kimeridge Clay. Mr. Topley, who has examined
the specimens below the depth of 376 feet, reports that slight indications of
petroleum have been noticed all through the clay. He has been able to record
no less than twenty forms of Mollusca (the species cannot always be identi-
fied) and some fish-remains. Ammonites biplex, Cardium, Modiola pectinata,
and Lingula ovalis are the most abundant fossils in the Kimeridge Clay. It
is not quite certain at what exact depth in the boring the Kimeridge Clay
began, but it was probably about 290 feet from the surface, so that about
380 feet of it have been penetrated. Its total thickness at Netherfield (near

416 Progress in Science. (July,

Battle) was estimated at 400 feet, so that no doubt the bottom will soon be
reached.

The discovery of beds of gypsum between the depths of roo and 180 feet, in
the Purbeck Beds, and which would probably never have been known but for
this scientific enterprise, have been already sought for and found at Archer’s
Wood, on the estate of the Earl of Ashburnham. As Mr. Willett observes,
it is a matter of congratulation that by this discovery there has been developed

for the county a new industry, which promises to be highly remunerative to all
parties.

Geological Society of London.—This Society has just commenced the re-
moval of its Library and Collections from Somerset House to the new apart-
ments prepared at Burlington House. The superior accommodation, which
was more especially wanted to display the large collections of rocks and
fossils, will no doubt be appreciated by the Members.

The late Professor Phillips\—The scientific world at large, and geologists
particularly, have sustained a great loss in the death of Professor Phillips.
Few men have possessed so wide a range of knowledge, and no one has done
more to further the advance of Geology, by special work in all its departments,
than John Phillips. He was born in 1800, and, being early left an orphan,
was adopted by his uncle, William Smith, the Father of English Geology.
From his sixteenth year he accompanied Smith in his various geological
journeys across England, and was thus early trained to accurate observation
in the field by his uncle, whose early teachings directed the whole course of
his life. In 1825 he was appointed Keeper to the Museum of the Yorkshire
Philosophical Society, a post which he held until 1840, when he was appointed
to the Geologica} Survey under De la Beche, and not only did much detailed
work in the field, but described the Palzozoic fossils collected in West Somer-
set, Devon, and Cornwall. In 1834 Mr. Phillips was elected to the Chair of
Geology in King’s College, London; in 1844 he was appointed Professor of
Geology in the University of Dublin; and in 1853 he was called to the duties
of Reader in Geology in the University of Oxford. In 1859 he was elected
President of the Geological Society of London, and in 1864 President of the
British Association, of which latter body he was one of the founders. The
writings of Professor Phillips were very numerous. At the time of his death
he was preparing a new edition of his ‘* Geology of Yorkshire.”” He died on
the 24th of April, having met with a severe accident on the previous day,
falling headlong down a flight of stone stairs.

PHYSICS.

Microscopy.—Mr. F. H. Wenham has described* a more accurate mode of
measuring the angular aperture of microscopical objectives than that hitherto
practised. The angle of aperture of an object-glass is taken from the focal
point through which the rays must pass for all degrees. Those entering at
other angles within the plane of focus will give a false indication, from diffused
light forming no image. Mr. Wenham employsa movable slit of thin platinum-
foil so mounted as to be secure from damage from accidental contaé& with the
objeé-glass, or otherwise. This instrument is placed upon the stage of the
microscope, with the body horizontal, and set on a wooden turntable about
to inches in diameter, having its edge divided into degrees. The object-glass
to be measured 1s focussed on the glass surface, and the slit adjusted so that
its two edges just appear in the field of view, and by the rotation of the turn-
table the degrees of aperture are read off. The microscope should have a thin
stage, so that the rays may not be cut off at extreme angles. Measurements
taken with these precautions come out much lower than those by the ordinary
mode, as the image-forming rays alone enter into the objective. Mr. Wenham
considers the large front glasses of many objectives not only useless but
injurious, and the performance of such glasses is much improved by turning
away the front, so as to only leave the actual working portion to receive the

* Monthly Microscopical Journal, vol. x1., p. 198.

1874.] Physics. 417

pencil from the obje@. Many fine glasses perform indifferently under certain
conditions of illumination from the above cause, but, by placing a cap with a
suitable aperture to excludg useless light, the definition is rendered perfect.
The celebrated American }th objective, marked as having an angular aperture
of 180°, isa remarkable instance of erroneous measurement obtained by receiving
false light. The following are the data :—Diameter of front lens, 0'043 of an
inch; working distance, o:013 of aninch. From these measurements, 118° is
the utmost that can be obtained, supposing all the light entering takes part in
the formation of the image; this glass, measured in the ordinary way, admitted
light up to 180°.

A series of more than eighty slides for the magic-lantern, illustrating geology
and paleontology, have been published by Mr. James How, of Foster Lane;
they are uniform in size with Dr. Maddox’s micro-photographs, and are photo-
graphed from the best drawings and engravings of various fossils, sections of
strata, and sedimentary formations. New photographs are in preparation; the
series will prove of great value in illustrating leGtures on geological subjects.
It is to be regretted that the colour and condition of most geological specimens
is such as to prevent good photographs suitable for lantern magnification being
taken directly from them.

We have to record the death of Mr. Henry Deane, F.L.S., F.M.S., F.R.M.S.,
which took place suddenly at Dover on April rr. Mr. Deane joined the Royal
Microscopical Society (then the Microscopical Society of London) at its com-
mencement in 1840, and was associated with Messrs. Bowerbank, Bell, Mantell,
Quekett, and other pioneers of microscopical science. In 1845 he discovered
the existence of Xanthidia and Polythalamia in the grey chalk of Folkestone,
also the now well-known Arachnoidiscus Faponica on the sea-weed used by
the Chinese for preparing soup. He was also the first to introduce gelatinous
mounting media, Deane’s gelatine being still employed by microscopists,
and considered a most reliable material. It is, however, with the foundation
and progress of the Pharmaceutical Society that Mr. Deane’s name will be
longest remembered. He became one of the Board of Examiners in 1844, and
introduced many imprevements of a highly practical nature into the examina-
tions, practical dispensing being one of the most notable. He was elected
Member of Council in 1851, Vice-President shortly afterwards, and President
in 1853 and 1854. Mr. Deane was Chairman of the Committee appointed to
assist the College of Physicians in compiling a new Pharmacopeeia, and also
President of the first British Pharmaceutical Conference. Very few papers
were written by Mr. Deane, although his work, both with the microscope and
in chemical and pharmaceutical science, was considerable. Attention may,
however, however, be called to “Displacement as a Method of Preparing
Tinctures, &c.;’’* ‘ Experiments on Senna;’’{ also some on opium prepara-
tions and extract of meat, in conjunction with Mr. H. B. Brady.

The subject of cutting sections for the microscope has been very fully discussed
at the Quekett Microscopical Club. A large collection of machines were
exhibited and described by Mr. E. T. Newton. The points considered most
needful to a perfect seGtion-cutter were a true guide-plate, and a very accurate,
finely-divided, and tight-fitting screw; a large tube is to be preferred to one
of small bore, and the machine should be firmly clamped to the table or bench.
' Opinions were divided as to the form of the cutting instrument, some being in
favour of a knife with a blade broad at the heel and narrow at the point, and
others preferring a straight edge; all, however, ayreeing that the blade must
be so strong that it will not bend under the necessary pressure, as in that
case it would dip down and cut an uneven seétion, besides being liable to
come in contact with the edges of the tube and consequently be blunted.
It is hardly necessary to mention that success entirely depends upon the
knife being extremely sharp. Some experienced operators consider a sharp
knife the chief requisite, dispensing with the aid of a machine, and trusting
entirely to steadiness of hand. Dr. Hoggan has contrived a machine differing

* Pharm. Journ,, vol. i., p. 61. t Ibid., vol. iv., p. 61.

418 Progress in Science. {July,

entirely from those on the tube fronciple almost universally employed.
The substance to be cut is attached to a plate worked by a screw somewhat
after the manner of the well-known slide-rest of the lathe; the contrivance
which is adapted for cutting sections of either hard or soft substances, has
means of keeping the saw or knife rigidly in position while at work. Among
the substances used for imbedding tissues to be cut, carrot and elder-pith
seemed to offer especial advantages. The process of freezing soft tissues
gives good results, and is convenient, because the tedious process of hardening
with alcohol or chromic acid is dispensed with; gum-water should be used
for imbedding, as water when frozen blunts the knife at the first cut, owing to
its becoming crystallised.

Heat.—M. Berthelot, writing on refrigerating mixtures, says the thermal
effe& produced when ice is mixed with bihydrated crystallised sulphuric acid
is the sum of three effects, viz., the fusion of the acid and that of the ice,
which absorb heat, and the combination of the two liquids, which liberates
heat. The numbers obtained in practice are under those calculated from
theory, owing to loss through radiation. The author shows from theory that
no method of cooling is comparable to vaporisation, and he thinks that much
higher temperatures may yet be had by means of it.

In prosecuting experiments to ascertain the expansion of various
substances by heat, the following experiment was tried:—The bulb of
a thermometer was suddenly plunged into melted lead. The mercury
instantly darted down far below zero. The action was so quick that the
point could not be ascertained. This was caused by the sudden expansion
of the bulb by heat before it reached the mercury by conduétion; this
then began to rise very rapidly, and before it had arrived at the top of
the tube the bulb was withdrawn. The experiment requires adroitness,
for, as we all know, the instant that the mercury touches the top, the
bulb will burst. This must be greased before immersion in the fused lead,
otherwise a film of the metal will adhere and retain sufficient heat to carry
the mercury to the top with a consequent fracture. A thermometer treated
in this rough manner afterwards showed an index error of six degrees, the
mercury having risen to that extent ; but after a few days the equilibrium was
partly restored, and the error remained permanently at three degrees.

Dr. H. Beins in considering the question how to transform heat into
mechanical power more advantageously than it is done in our common steam
and other engines, found that when natrium-bicarbonate (or the corresponding
salt of kalium) in a dry pulverised state or in a watery solution is heated ina
closed space, a part of the carbonic acid is given off and condensed in a not
heated portion of that space, so that at a temperature of 300° to 400° C,
liquid carbonic acid can be distilled out of those salts with a tension of from 50 to
60 atmospheres. The author hasexperimentally found that a carboleum-engine
is easily constructed. Taps and joints can be made to answer perfe@ly. A year
ago he filled a tube of hammered copper with carbonic acid of 50 atm., and
not the least loss is as yet observed. Wrought metals are therefore not
permeable for gases of that tension. Perhaps the phenomena of porosity,
belonging to the common air-pump experiments, are partly caused by surface-
condensation. For the great industry, the carboleum-engine can in almost
every case substitute the steam-engine. For the small industry, specially
for engines working with intermissions and during brief spaces of time, the
property of carboleum of being always ready for work is of much importance;
for instance, for printing-presses, fire-engines, street-locomotives, &c. By this
same property, and since the mechanical equivalent of electricity is very small,
a carboleum-engine is a fit and cheap source of electrical light. This method
of compression furnishes easily the required tension for the conveyance of
letters in tubes, and the modern break apparatus for railways. Perhaps the
property of carboleum of possessing a power of projection a hundred times
cheaper than gunpowder can be made use of. The fact that a carboleum-
engine with sufficient store of carboleum is independent of our atmosphere,
makes it possible to construct a vessel, provided with means to sink to any
depth of the sea, to rise and sink at will, to cruise about under water, and to
maintain the life of the crew during that operation, to develop light, &c. The

1874.] Technology. 419

importance of this for scientific discoveries and industrial purposes is evident.
For the purposes of war, also, must such a small and comparatively cheap
submarine vessel place a peculiar, nay a decisive, weight in the scale in the
question of our modern ironclads. Freezing machines working by evaporation of
carboleum produce ice at a much less cost than any existing freezing apparatus.
Regarding this general usefulness of carbonic acid, it is important to call
attention to the faé& that an inexhaustible store of carboleum. is at our dis-
position in common chalk, for this mineral contains carbonic acid to the
amount of half its weight; it can therefore produce twice its volume of
carboleum.

Evectricity.—M. Clamond has been improving his thermo-eleétric pile.
He found in it a considerable increase of resistance, and this was
due to two causes—(r1) Oxidation of the contracts of the polar plates
with the crystallised bar under the influence of heat ; and (2) split-
ting of the bar and separation of its different parts in planes perpen-
dicular to its length. In making his couple he uses an alloy of zinc
and antimony, and plates of iron as armatures. The bars are collected in
crowns of ten bars each, superposed and separated by washers of amianthus,
and coupled for tension. The whole forms a cylinder, the interior of which is
luted with amianthus, and heated by means of a pipe of refractory earth
pierced with holes. The gas mixed with air burns in the annular space
between the tube and the bars. The entire surface of the crowns of the pile
is 35 Square decimetres. The consumption of gas is controlled by M. Girond’s
regulator. Thus arranged, the pile will work whole months without requiring
attention, giving a current absolutely constant. A model exhibited consumed
170 litres, that is, about 5 centimes of gas in the hour, and deposited 20 grms.
of copper, which makes the expense of gas per kilogrm. of copper deposited
2 francs 50cents. M. Clamond has made models of various size; the quantity
of electricity increases proportionally to the size of the pieces.

The lever of an electric automatic whistle for locomotives is wrought
by an elefro-magnet. On passage of a current in a certain direction

_ the magnet lets go the lever, and the whistle sounds. The apparatus

is connected by insulating wires with a metallic brush projecting
below the locomotive. At a short distance in front of the sight signal there
is a metallic plate between the rails, which, when the signal is turned in the
position for stoppage, is connected with a source of electricity. On passage
of the brush over the plate the current flows and the whistle sounds. It con-
tinues to do so till adjusted again by the engine-driver. The Chemin de Fer
du Nord have used the system, which is the invention of MM. Lartigue and
Forest, eight months, and with satisfactcry results.

The following safety eleGric cable against fires is proposed by MM. Joly
and Barbier:—Two wires, insulated from each other by gutta-percha, are
corded together into a cable, and are connected at one end with a battery and
electric bell. When fire breaks out in any part of the building through
which the cable passes the gutta-percha is freed and the wires come in con-
tact, thus closing the circuit and ringing the bell. The condition of the ap-
paratus is tested by means of a peg commutator at the other end of the cable.

TECHNOLOGY.

A new use of glycerin is to prevent the formation of incrustation in steam-
boilers. M. Asselin, of Paris, recommends the addition of glycerin in the
proportion of 1 kilo. for every 5000 to 8000 kilos. of fuel consumed, on account
of its power of increasing the solubility of sulphate of lime, and causing the
undissolved portion to be precipitated in a granular form, so as not to adhere
to the metal.

As a system of continuous alarum signals to prevent collisions, on railways
or at sea, in foggy weather, M. de Mat proposes to compress air in a cylin-
drical reservoir, from which a tubulure conveys it to three organ pipes (giving
do, mi, sol), whick can be sounded separately or together. In fog the do is
sounded, and whenever an engine-driver hears it in an advancing train he
sounds his mi, the other driver then sounds his mi if he is on the right line,
then both sound sol.

( 420 )

LIST OF PUBLICATIONS RECEIVED FOR REVIEW.

A Manual of Botany, Anatomical and Physiological, for the Use of Students.
By Robert Brown, M.A., Ph.D. Wm. Blackwood and Sons.

Botanical Tables for the Use of Students. Compiled by Edward B. Aveling,
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Divine Revelation or Pseudo-Science? By R. G. Suckling Browne, B.D.
Longmans, Green, and Co.

Algebra Identified with Geometry. By A. J. Ellis, F.R.S.
C. F. Hodgson and Sons.

Theory of Arches. By Prof. W. Allan. New York : D. Van Nostrand.

A Treatise'on an Improved Method for Overcoming Steep Gradients on Rail-
ways. By Henry Handyside. E.and F.N. Spon.

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Geology. By T. G. Bonney, M.A., F.G.S., and

Physiology. By F. Le Gros Clark, F.R.S.
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The Correlation of Physical Forces. Sixth Edition. By the Hon. Sir W. R. —
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Plattner’s Manual of Qualitative and Quantitative Analysis with the Blowpipe.
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Harvey and His Times. The Harveian Oration for 1874. By Charles West,
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Elements of Metallurgy. By J. Arthur Phillips, M. Inst. C.E., F.G.S., &c.
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The Universe and the Coming Transits. By R. A. Proctor, B.A.
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Arithmetic in Theory and Praétice. By J. Brook-Smith, M.A., LL.B. 2nd
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The Sanitary Condition of Oxfordshire. By Gilbert W. Child.
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Principles of Mechanics. By T. M. Goodeve, M.A.
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CONTENTS OF No. XLIII-

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Baird’s “‘ Annual Record of Science and Industry for 1873.”

Beard’s ‘‘ Legal Responsibility in Old Age.”

Timbs’s ‘* The Year Book of Faéts in Science and Art.”

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PROGRESS IN SCIENCE,

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CONTENTS, OF No. XIETV.

AN EXAMINATION OF THE THEORIES THAT HAVE BEEN
PRoPOsSED TO ACCOUNT FOR THE CLIMATE OF THE

GuaciaL Periop. By Thomas Belt, F.G.S.
Loss oF Lire aT SEA. By Rear Admiral Fishbourne. .

THE LuNAR ATMOSPHERE AND ITS INFLUENCE ON LUNAR

Questions. By Edmund Neison, F.R.A.S., &c..

BERYLS AND EMERALDS. By Professor A. H. Church,
M.A., &c. |

On THE CURVED APPEARANCE OF ComETs’ Talis. By
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NOTICES OF SCIENTIFIC WORKS,

Chappell’s ‘‘ History of Music”

~West’s “‘ The Harveian Oration for 1874”

Brown’s *“ Divine Revelation, or Pseudo-Science ?”
Grove’s “‘ The Correlation of Physical Forces ”
Proétor’s ‘The Universe and the Coming Transits ”

Lardner’s ‘‘ Handbook of Natural Philosophy ”

PAGE

431

405

492

504

508

516
522
523
524
528
531

CONTENTS.

Richter’s ‘‘ Plattner’s Manual of Qualitative and Quantitative
Analysis with the Blowpipe ”

Allan’s ‘‘ Theory of Arches” .
Bonney’s “ Geology”

“Fourth Annual Report of the Board of Commissioners of Public
Charities of the State of Pennsylvania”.

Rutley’s ‘‘ Mineralogy” .
Goodeve’s “‘ Principles of Mechanics” .
Phillips’s ‘‘ Elements of Metallurgy”

Girard’s ‘‘ Le Monde Microscopique des Eaux”

PROGRESS IN SCIENCE.

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532
533
534
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Including Proceedings of Learned Societies at Home and Abroad, and

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MINING . 5 5 : 5 ‘ : : : rs 3 A
METALLURGY

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THE QUARTERLY

meu NAL, OF (SCLE NCE:

OCTOBER, 1874.

BAN EXAMINATION: OF THE: THEORIES
THAT HAVE BEEN PROPOSED TO ACCOUNT FOR
fre CLIMATE OF THE GLACIAL PERIOD.

By Tuomas BELT, F.G.S.

~

ps the speculations I ventured to make ina recent work*
on some of the phenomena of the Glacial period, I

purposely avoided entering on the question of the
cause of the great accretion of ice, believing that the time
was not ripe for its discussion, and hoping that it might be
taken up by some astronomer, as it is to Astronomy rather
than Geology that we must look for a solution of the
problem. I find, however, that my explanations of the
facts of the “great ice age” are constantly met by objec-
tions founded on the theories of the cause of that event;
and I propose in the present paper to discuss the principal
hypotheses that have been advanced to account for the
origin of the Glacial period, and to endeavour to show that
my speculations on the extent and effects of the ice are in
accordance with, and a necessary consequence of, the
theory that is most in harmony with the facts with which
we have to deal.

1. Theory of a Change in the Relative Position of the Conti-
nents and the Ocean.—In that great work the ‘‘ Principles of
Geology,” in which the foundations of the modern science
were laid in 1830 by Lyell, and in successive editions in
which the veteran philosopher has ever kept abreast of
advancing knowledge, he has brought forward and supported
the theory that great oscillations of temperature have been
produced by changes in the relative positions of land and
water. This theory he has enforced with a wealth of illus-
tration derived from his vast acquaintance with geological
and geographical facts, and by the masterly arguments of
a clear, comprehensive, and judicial mind. Chiefly through

* The Naturalist in Nicaragua, p. 262.
VOL. IV. (N.S.) 3H

422 Climate of the Glacial Period. (October,

his powerful advocacy, after nearly half a century has
elapsed, it still holds its ground amongst the rival views
that have been advanced, and deserves our first con-
sideration.

Lyell takes for his starting-point the undoubted fact that
the sea and the land are now in some parts changing places.
Along some coast lines the land is either slowly sinking or
has sunk in post-glacial times, whilst in others the conti-
nents have been raised above their former level. He
proceeds to show that the climate of a place is greatly
dependent upon its position with respect to great masses of
land or water; that an insular climate is less extreme than
that of the interior of a great continent; and that currents
of water from the tropics, or from the ar¢tic regions, are
very effectual in raising or lowering the mean temperature
above or below what is due to distance from the equator
alone. He then considers what change in the relative
position of land and water would produce the warmest
and what the coldest climate, and comes to the con-
clusion that if all the land was distributed around the
equator we should have the warmest climate possible due
to geographical conditions, and that if all the land was
situated at and around the poles we should have the
extreme of cold.

There can be little doubt that if the second set of condi-
tions prevailed, or even some approach to them, they would
be effeCtual in rendering more severe the climate of polar
regions, and in causing a greater accretion of ice than now
prevails. A rise of polar and a submergence of tropical
lands would certainly lower the temperature of the arctic
regions. A mere rise-of land, sufficient to close Behring’s
Straits and to connect America through Newfoundland with
Europe, would, by shutting off all warm currents from the
polar seas, tend to a greater accumulation of ice, as the
heat of the Gulf Stream and other warm currents—that is
now expended in tempering arctic seasons and melting polar
ice—would then cause greater evaporation, and consequently
greater precipitation, on the frozen lands of the north.
But it must not be forgotten that the warm currents flowing
northwards are counterbalanced by cold ones flowing south-
wards; and if, on the one hand, regions enjoying a warmer
climate through the influence of the Gulf Stream would then
be shut off from its influence and subjected to greater cold,
so, on the other, coasts—such as that of eastern North
America—now cooled by polar currents, would be laved by
warmer waters. Yet it is on the eastern side of North

1874.] Climate of the Glacial Period. 423

America that the ice extended farthest towards the equator
in the Glacial period.

When Lyell first propounded his theory geologists were
very imperfectly acquainted with the facts that were to be
explained, and it was thought that if it could be shown that
by an alteration in the configuration and distribution of
land, and a change in the direction of the currents of the
ocean, icebergs might be floated down to the latitude of
London, lowering the temperature as they do now in South
Georgia in lat. 54° S., so as to allow of a perpetual covering
of snow and the existence of glaciers on the higher grounds,
a satisfactory solution of the problem would be arrived
at. But in the half century that has nearly passed since then
our conceptions of the extent of the ice of the Glacial period
have slowly but greatly expanded, and we know now—
although many English geologists still close their eyes to
the evidence—that the problem to be solved is not one of
icebergs floating over submerged lands, but a vast piling up
of ice and snow around the poles, that accumulated until it
flowed outwards over the existing continents. Let us trace
this great ice-sheet round the northern hemisphere, as we
are now nearly enabled to do by the latest observations on
its extent in northern Asia.

Commencing in North America, we learn from Dana and
other eminent American geologists that to the north of the
St. Lawrence the ice was at least 12,000 feet, or 24 miles,
in thickness; in the northern parts of New England was
over 6000 feet in thickness, and, gradually thinning south-
wards, reached in the lower grounds the parallel of 39° N. in
the southern parts of Pennsylvania, Ohio, Indiana, Illinois,
and Iowa, whilst along the mountain ranges local glacier
systems reached in the tropics at least as far as Nicaragua,
where within 13 degrees from the equator I found undoubted
traces of glacier action reaching to 2000 feet above the
sea-level, where snow now never falls.

Coming eastward we find, in Nova Scotia and Newfound-
land, everywhere evidence that they were completely over-
whelmed with ice. Iceland, according to Robert Chambers,
is scored across from one side to the other, and was buried
in ice that may have reached the British Isles, for the
Hebrides and the north-eastern extremity of Scotland were
overflowed by ice that came from that dire¢tion. ‘This ice,
overflowing Caithness, joined by great streams from Scandi-
navia, and further reinforced by glaciers from the mountains
of Scotland and the north of England, pushed down the bed
of the German Ocean, reached as far as the coasts of

424 Climate of the Glacial Period. (October,

Norfolk, and thrust up great masses of chalk and other
angular rocks upon the land. We have a measure of its
thickness in Southern Yorkshire, and learn that it was not
so deep on the eastern as it was on the western side of
England, for the drift does not reach higher than 600 feet
above the sea, excepting where the Wye, the Calder, and
the Aire cut through the Pennine Chain, and form passes
through which the ice streamed from the west, where it was _
much higher. The Irish Sea was filled with it, flowing
southwards, at least 2000 feet thick. It butted against the
Welsh mountains, and, dividing, one part pushed up the
valleys of the Mersey and the Dee, and through what has
been called the Straits of Malvern, certainly as far as the
water-shed of the Severn, probably as far as the Bristol
Channel; the other and larger stream, shouldering the
western slopes of the mountains of Cardiganshire, flowed
across Anglesea to the Atlantic. In Ireland the ice was
still thicker, and Mr. Campbell considers that in the extreme
south of that island he has obtained proofs of it having been
at least 2000 feet thick. This thickening of the ice west-
ward proves that the British Isles were not glaciated from
Scandinavia.

Passing across to the continent we find Scandinavia hugely
glaciated, and that the ice-sheet that flowed from it filled the
Gulf of Bothnia and the Baltic. Denmark was assailed by
the advancing ice, and everywhere traces are left of its vast
extent and force. Inthe island of Moen the chalk strata
are dislocated and folded together, inclosing in their folds
patches and seams of boulder clay. The Danish geologists
have ascribed these to a faulting and bending of the strata
since the Glacial period; but both in Nova Scotia and at
Abergairn, in Aberdeenshire, I have seen great masses of
strata that have been pushed along horizontally over others
by the great force of the advancing ice, and think that the
post-tertiary contortions of the strata in Moen must be due
to the same agency. After crossing the Baltic the ice crept
southwards, and all over northern Germany and Holland
blocks of stone strew the surface that have been brought by
it from the mountains of Norway and Sweden. It
reached its southern limit somewhere about Antwerp, and
eastward the range of the northern drift has been traced to
an irregular line across the Continent. In European Russia
the ice reached to Nijni Novgorod, in lat. 52°; to which
parallel I have also traced it in north-western Asia, near
Pavlodar, in Siberia, and in a paper read before the Geolo-
gical Society of London have described the facts that have

1874.] Climate of the Glacial Period. 425

led me to the conclusion that the ice from the north
blocked up the whole water-shed of Siberia as far as the
borders of Kamtchatka.

We thus find everywhere in the northern hemisphere that
the ice thickened northwards, that it radiated from the pole;
and that its margin nearly girdled the world, and probably
would be found to have done so completely if there were
land to preserve its traces.

There are many geologists who believe that these northern
lands were not all glaciated at the same time,—that, for
instance, the Glacial period of North America was not con-
temporaneous with that of Europe. Those who thus argue
adopt, in some form or other, Lyell’s theory that the cold of
the Glacial period was produced bya change in the distribu-
tion of land and water. Thus Mr. Hopkins, in 1852, calcu-
lated that if—by some change in the relative position of sea
and land—the Gulf Stream could be diverted from its present
northerly course, whilst northern and western Europe were
submerged to the extent of 500 feet, and subjected to the
influence of a cold current passing over the depressed area,
the snow-line would descend to 1000 feet above the sea-level
in Wales and the west of Ireland, and glaciers would reach
the sea. Although this amount of change would be totally
insufficient to account for the facts of the Glacial period, it
may still be useful to point out that not a single scrap of
evidence has been adduced to show that the Gulf Stream
ever passed over any portion of Europe or America that is
now dry land.

Throughout the whole of the Tertiary period the conti-
nents appear to have had much the same area and figure as
they at present possess. Dana has also pointed out that,
even so far back as the Jurassic period, the Gulf Stream
exerted the same kind of influence upon the temperature of
the North Atlantic as it does now. He considers that the
existence of corals in the English oolites proves that the
coral reef boundary extended 22 degrees of latitude beyond
its present farthest northern point, and believes that the
Gulf Stream must have aided in this result. Other facts
indicate its existence and influence in cretaceous and tertiary
times,—as, for instance, the representatives of the French
Faluns on James’s River, in North America, denote a cooler
climate in lat 37° N. than prevailed at the same time in
lat.47°N.in Western Europe,—whilst in the glacial epoch the
extent of the ice in Western Europe and Eastern North
America curiously and suggestively conforms with the curve
of the present isothermal lines due to its action. Just as

426 Climate of the Glacial Period. (October,

now, the isotherm of 50° F., passing across the south of
England near the latitude of London and the Bristol
Channel, sweeps south-westwardly across the Atlantic, and
reaches to about Baltimore, in North America, so in the
Glacial period the margin of the ice, flowing southwards,
attained nearly the same limits; indicating that the warm
waters from the tropics then, as now, were deflected against
the western coasts of Europe by the rotation of the earth,
and gave them a higher temperature than the same lati-
tudes on the eastern coasts of America. The sea teems
with life, and it is not possible that this current could have
flowed over any part of Europe without leaving many me-
morials of its course behind it. But even if it had been
diverted, and a cold current brought icebergs from the Arctic
regions past the British Isles, how could that, or any modi-
fication of such a theory, cause continental ice to reach the
sea-level in lat. 39° in North America? I cannot imagine
any alteration of the present coast-lines that could cause a
greater curve in the isothermal lines than at present exists
in the North Atlantic ; and to assume that during the Glacial
period the warm and cold currents shifted their position all
round the hemisphere, so as to bring every part, at one time
or other, within a greater extreme of cold than now any-
where prevails, is to call for an amount of movement in
the earth’s crust that no evidence warrants nor analogy
suggests.

Whilst Lyell, in his latest works,* adheres to his opinion
that former changes of climate have been chiefly governed
by geographical conditions, he candidly admits that since he
first attempted to solve the problem, our knowledge of the
subject has vastly increased, and that it has assumed a some-
what new aspect, so that he now considers it probable that
astronomical causes may have combined with geographical
changes to produce an exaggeration of cold in both hemi-
spheres. The principal of these astronomical theories I
shall now take into consideration, but I shall have in the
sequel—when I come to show what bearing the fa¢ts of the
Early Tertiary period have on the discussion—to make some
further remarks upon the insufficiency of geographical
changes to account for the great oscillations of temperature
of which we have geological proofs.

2. Theory of an Increase of the Ellipticity of the Earth’s
Orbit.—Mr. Croll, in a series of papers published in the
‘** Philosophical Magazine,” has advocated, with great ability

* Principles of Geology, 1872, pp. 173 and 284.

1874.] Climate of the Glaciai Period. 427

and learning, and strengthened by laborious calculations,
the theory that the cold of the Glacial period and the warmth
of other geological epochs were due to great changes in the
ellipticity of the earth’s orbit. As has long been known,
the earth, in its annual course around the sun, does not
describe a circle, but an ellipse, and is much nearer to the
great luminary in some parts of its course than in others.
Astronomers have also proved that the eccentricity of the
orbit varies during vast periods of time, and that at its
greatest eccentricity—one of which periods happened about
200,000 years ago—the earth in aphelion was nearly
98,500,000 miles distant, whilst now when in aphelion it is
about 90,000,000 miles from the sun.

One result of the eccentricity of the orbit, combined with
the obliquity of the ecliptic, or the angle that the axis of the
earth makes with the plane of its orbit, is, that at present
the sun is north of the equator about 7+ days longer than
it is south of it. But as at the time the sun ts south of the
equator the earth is nearest the source of heat, the southern
hemisphere receives just as much heat in its shorter summer
solstice as the northern hemisphere does in its longer one.
Astronomers have calculated the effect of a much greater
eccentricity of the orbit, and have unanimously come to the
conclusion that the absolute amount of heat received by the
two hemispheres would be the same, however great that
eccentricity might be. But as the total amount of heat re-
ceived from the sun is inversely proportional to the shortest
diameter of its orbit, it follows that during the periods of
greatest eccentricity the absolute amount of heat received
by the earth, and distributed equally to the two hemispheres,
would be slightly in excess of that received when the eccen-
tricity was much less.

The general conclusion arrived at by astronomers before
Mr. Croll examined the problem—including the eminent
names of Humboldt, Arago, and Poisson—was that the
climate of our globe could not be affected by any possible
change in the ellipticity of its orbit. In this opinion
Herschel—who at one time thought that great changes of
climate might be so produced—appears afterwards to have
coincided. Mr. Croll, however, states that in arriving at
this conclusion a most important element of the enquiry
had been omitted. Fully admitting that the absolute
amount of heat received in the two hemispheres would be
the same, however great the ellipticity might be, he yet
urges that in that hemisphere in which the nights were
longest there would be most heat lost by radiation, and

428 Climate of the Glacial Period. (October,

in that way the mean temperature would be greatly
lowered.

Mr. Croll puts his theory briefly in these words :—‘‘ The
southern hemisphere is further from the sun during its winter
than the northern, and therefore cools more rapidly. It is,
however, nearer to the sun during its summer than the
northern, and on this account cools more slowly. The heat
thus saved during summer would exactly compensate for
that lost during winter were the two periods of equal length ;
but as the southern winter is longer than the southern
summer by more than 74 days, there is on the whole a
greater amount of heat lost during winter than is saved
during summer.” ‘‘ The greater length of the winter half
year over the summer half, when the eccentricity is near its
maximum, would affect the climate in two different ways :—
(1), by allowing the ground to cool by radiation to a greater
extent than it would otherwise do were the (summer)
seasons of greater length; and (2), by lengthening the ice-
accumulating period and shortening the ice-melting period.
The influence of the first cause upon the glaciation of the
country would probably be felt to a considerable extent ; but
it is to the second that we must attribute the principal
effect.”* The above was written in 1865, but I cannot find
that Mr. Croll has modified his theory in any later writings ;
and Mr. James Geikie, his colleague on the Geological
Survey of Scotland, has, during the present year, in his work
“‘The Great Ice Age,” adopted it, and in discussing it has
described it substantially as above. Now if it be true that
the hemisphere, that has its winter when the earth is farthest
from the sun, will have its mean temperature reduced by
an excess of radiation; whilst that of the opposite hemi-
sphere will be correspondingly increased, we have certainly
a true cause of former great oscillations of climate. Before,
therefore, entering on the consideration of some other
causes that would, according to Mr. Croll, be brought into
action and intensify the effects, it will be well to examine
the fundamental bases of the theory.

Ist. Would there be more radiation of heat into space,
and consequently increased cold, at times of the greatest
ellipticity of the orbit in that hemisphere whose winter
happened when the earth was furthest from the sun?
Mr. Croll, as we have seen, answers in the affirmative, and
in the shape in which he puts it it appears as if it would be
so. As at that time the number of hours of night in each

* Reader, 1865, p. 631.

1874.] Climate of the Glacial Period. 429

year were much more in one hemisphere than the other, it
is quite certain that more heat would be radiated during the
nights that were longest. But, and this is the fallacy on
which it seems to me Mr. Croll’s argument rests, the earth
radiates heat in the day time as well as at night, and this
has not been taken into consideration. The warmth of
the day depends on the excess of heat received over what
is radiated, not that there is no radiation at that time; and
if we take into account the heat radiated during the day we
shall find that no more is lost in one hemisphere than the
other from that cause. And if the absolute amount of heat
received from the sun be equal whatever the amount of
ellipticity, and the absolute amount of loss. by radiation
also equal when we calculate that radiated during the day
as well as that during the night, it is evident that the
absolute difference between the heat received and the heat
lost, or the mean temperature of the two hemispheres due
to these causes alone, must be the same whatever the
amount of ellipticity of the orbit may be.

and. Would the lengthening of the ice-accumulating
period and the shortening of the ice-melting period cause a
greater accretion of ice? Here again Mr. Croll and his
followers answer unhesitatingly in the affirmative, and they
put it in this way :—‘“‘ At the time of greatest eccentricity
during the long winter of aphelion, longer by thirty-six
days than the summer of perihelion, such an accumulation
of snow and ice would have taken place that even the
diminished distance between the earth and the sun in
summer time would be powerless to effect its removal.’’*
Here, again, I think the argument is based on a miscon-
ception. It is not a fact that our winter begins as soon as
the sun has passed the autumnal equinox, though what
is called the winter solstice does. The nights are longer
than the days, but snow does not immediately begin to fall
nor water to freeze, and our winter does not commence on
the 22nd of September, but several weeks later. In the
shorter but hotter summer of perihelion some excess of
heat must be stored up in the earth, the sea, and the
atmosphere, not to be entirely given up until long after the
winter solstice has been entered on. ‘The advocates of this
theory affirm that the mean temperature would be lowered
because the heat of the short summer would be taken up
in melting the ice that had accumulated in winter, but a
pound of water in passing from a liquid to a solid state

* The Great Ice Age. By JAMES GEIKIE. 1874. P. 139.
VOL. IV. (N.S.) 31

430 Climate of the Glacial Period. [Oétober,

evolves just as much heat as is required to melt it again,
and the heat given off in winter by the freezing water is
equal to that absorbed when it melts again, so that the mean
temperature is not affected.

Again, it is said that clouds would accumulate around the
pole with its winter in aphelion. Why they should do so
does not appear very clearly, but clouds would*receive the
rays of the sun on their upper surface, and in some way or
other the heat would be utilised in ameliorating the climate ;
nor should it be forgotten that clouds prevent radiation
during the night as well as intercept the sun’s rays during
the day.

There is, however, a cause not touched upon by Mr.
Croll that does act in preventing the excess of heat of
summer counterbalancing its diminution in winter where
snow covers the ground. It is not because the heat is
used up in melting the snow, but because much of it is
not so used up but is reflected back into space from the
white surface. If it were not for this, snow would nowhere
be perennial, but everywhere the heat of summer would
dissolve the snows of winter; and if, without taking into
account any lengthening of the winter by reason of the
ellipticity of the orbit, the whole of the winter solstice were
an ice-accumulating period it would now gather year by
year until it overwhelmed the temperate zones, because the six
months’ snow would reflect so much of the other six months’
heat that it would not be melted but would gradually ac-
cumulate. It does not do so, because only at the very
poles are there six months winter and six months summer,
and the ice-accumulating period gradually decreases when
we leave the poles, and reaches zero long before we arrive
at the tropics. These conditions were probably the same
at the time of greatest ellipticity, and at the most onlya
very small amount of heat could be lost by reflection from
snow-covered lands more than now: and as at that time—
according to the law that the amount of heat received is in
inverse proportion to the length of the shortest diameter of
the orbit—there would be a slight increase in the absolute
amount of heat received from the sun, it is probable that
one would counterbalance the other; and I cannot but come
to the conclusion that Arago was right when he affirmed
that even if the ellipticity of the orbit was much greater
than astronomers have shown to be possible, ‘‘still this
would not alter in any appreciable manner the mean
thermometrical state of the globe.”

Mr. Croll has sought to strengthen his theory by

1874.] Climate of the Glacial Period. 431

endeavouring to show that other physical causes would be
brought into operation during a great ellipticity of the
orbit which would tend to decrease the temperature of the
hemisphere that had its winter in aphelion, and to increase
that of the other. The most powerful of these he con-
siders would be a change in the great currents of the
ocean by which at present a large amount of heat is con-
veyed from the tropics to the poles. He maintains that
these currents are produced by the trade-winds, and that
when the temperature of one hemisphere was reduced and
the other increased in the manner and by the causes already
discussed, the trade-winds on one side of the equator would
be weakened and on the other strengthened, and in con-
sequence the warm currents flowing towards the poles
would in one hemisphere be augmented and in the other
decreased, if not stopped altogether. For instance, he
considers that the Gulf Stream is produced by the action of
the trade-winds, and that in case of a great ellipticity of
the orbit when the winter of the northern hemisphere
happened in aphelion the air would be chilled, whilst that
of the southern hemisphere would be warmed, and thus
the aérial currents flowing from the poles towards the
equator would be altered. Under these circumstances
“the winds from the severe wintry north would sweep with
much more vigour towards the equator than the opposite
winds from the south pole. And hence Mr. Croll contends
that with weaker winds blowing from the south the great
antarctic drift-currents would be reduced in volume, while
the subsidiary currents to which they give rise, namely, the
broad equatorialand the Gulf Stream, would likewise lose in
volume and force. And to such an extent would this be
the case that, supposing the outline of the continents to
remain unchanged, not only would the Brazilian branch of
the equatorial current go on at the expense of the Gulf
Stream, but the Gulf Stream he thinks would eventually be
stopped, and the whole vast body of warm water that now
flows north be entirely deflected into the southern ocean.’*
Well may Mr. Geikie say that the effect of the withdrawal
from the north of all these great ocean rivers of heated
water would be something enormous.

But is Mr. Croll’s theory of the origin of the Gulf Stream
correct? Is it possible to believe that the great. body of
water in the Atlantic Basin would be warmed at one end
and cooled at the other without some system of circulation

* The Great Ice Age, p. 142.

432 Climate of the Glacial Period. (October,

being set up? If currents in the air are caused by the
unequal heating of different portions of it, why should not
currents in the ocean be in like mannerset in motion? Mr.
Carpenter contends, and has illustrated by experiment,
that they are; and if he be correct, instead of the Gulf
Stream being lessened by the increase of ice in the north, it
would be greatly augmented; and I have already shown
that there is evidence of its existence and influence in the
glacial period.

Another cause that Mr. Croll thinks might be a means of
increasing the vicissitudes of temperature produced by the
eccentricity of the orbit, is a change in the obliquity of the
ecliptic. Accepting the conclusions of some eminent
astronomers that the obliquity of the ecliptic can only vary
to a small extent, he yet considers that this small amount
would cause a great change of temperature; that when the
obliquity was at its maximum, or, according to Laplace,
24°50’ 34”, there would be an increase of temperature at the
poles equal to 14° or 15° if they were not covered with ice,
but if they were, then the total quantity of ice melted at
the poles would be one-eighteenth more than at the present.*
On the contrary, when the obliquity was at its minimum,
there would be a decrease of temperature at the poles and
an increase of the ice covering them. ‘This struck me
when I first read it as a most extraordinary conclusion, and
I considered it must have been the result of an inadvertence,
as it appeared obvious that the effe¢t would be just the re-
verse of that stated. But I find that Mr. Geikie, in his
recent work, follows Mr. Croll in this as in other matters,
and states that ‘if the obliquity of the ecliptic reached a
minimum during our glacial epoch, as indeed it must have
done more than once, the effect of the great eccentricity and
diminished obliquity combined would be to intensify the
glaciation of our hemisphere.” t

As, in the former argument, I have had occasion to show
that the radiation of heat by the earth during the day had
been neglected, so in this calculation the all-important fact
has been overlooked, that if the obliquity of the ecliptic be
increased, the arctic circle will be enlarged and a greater
area of the earth’s surface brought within the influence of
the long arctic night. A diminished obliquity, on the con-
trary, would lesson the difference in the temperate zones
between the length of the night and day, and in so far
moderate the extremes of cold and heat in winter and

4 Philusophical Magazine, vol. xxxiii, p. 436.
+ Great Ice Age, p. 147,

1874.] Climate of the Glacial Period. 433

summer. The fallacy of the argument can, however, be
best shown by considering what would be the effect of
diminishing the obliquity to zero. When the direction of
the axis of rotation of the earth became perpendicular to
the plane of its orbit, the difference of the seasons of the
year would disappear and perpetual spring would reign in
the arctic regions. All over the globe there would be
twelve hours night and twelve hours day, and no amount of
ellipticity of the orbit could have any effect in lengthening
the nights and days. Every step in the diminution of the
obliquity of the ecliptic would be an approach towards this
state of perpetual equinox, and tend more or less to equalise
the seasons. The theory of Mr. Croll is based on an
assumed exaggeration, by increased eccentricity of the
orbit, of the effects of the present obliquity of the ecliptic,
and it is startling to find it urged that a decrease in that
obliquity would increase the results.

Having thus shown that the foundations of the theory
present many points of weakness, I shall next take into con-
sideration the question of how far it is in harmony with the
geological facts sought to be explained by it. One of the points
insisted upon by Mr. Croll, and which is stated to be in ac-
cordance with the facts known to geologists, is that during
the greatest eccentricity of the orbit periods of glaciation
would alternate with others of great warmth. Whilst one
hemisphere was undergoing the extreme rigour of a glacial
period, the other would rejoice in a ‘‘ perpetual summer.”
And, owing to the precession of the equinoxes by which
there is a complete revolution of the equinoétial point in
21,000 years, in half that time the hemisphere that had its
winter in aphelion would slowly change until it had it in
perihelion. The ice that had been heaped up at one pole
would melt away and be piled up at the other. And as the
last greatest period of elllipticity occupied, according to
Mr. Croll’s laborious calculations, about 160,000 years,
there would during that time be several complete revolutions
of the precession of the equinoxes, so that each hemisphere
would have alternately several glacial periods and several
warm periods.

To prevent misconception I shall give Mr. Croll’s opinion
on this question in his own words. He says:—‘It is
physically impossible that we can have a cold and arétic
condition of climate on the one hemisphere, resulting from
a great increase of eccentricity, without at the same time
having a warm, equable, if not an almost tropical, condition
of climate prevailing on the other hemisphere.” ‘If the

434 Climate of the Glacial Period. (October,

Post Pliocene period afforded no geological evidence of a
warmer condition of climate in Europe than now prevails, it
would be so far a presumptive evidence against the assump-
tion that the glacial epoch resulted from cosmical causes.”
“Tf it should actually turn out that there is no such thing
as a warm and equable condition of climate somewhere
about the time of an ice period, then the whole theory
would have to be given up, because a warm period according
to theory is just as necessary a result of an increase of
eccentricity as a cold period.’’*

Now not only would the periods of great cold alternate in
each hemisphere with periods of ‘‘ perpetual summer,” ac-
cording to this theory, but as the ellipticity of the orbit
approached its greatest eccentricity, warm or genial climates
would alternate with colder ones, the extremes becoming
more and more marked as the time of greatest eccentricity
was neared. We ought therefore to find before the Glacial
period evidence of great changes of climate, alternations of
warm and cold periods, in the successive faunas, of which
we have the records preserved in the Tertiary rocks. Instead
of this, there are proofs of the gradual and continual
decrease of temperature in Europe from the earliest Tertiary
times. According to Lyell, ‘‘as we ascend in the series, the
shells of the successive groups of strata—provincially called
‘crag’ in Norfolk and Suffolk—are seen to consist less and
less of southern species, whilst the number of northern
forms is always augmenting, until in the uppermost or
newer groups, in which almost all the shells are of living
species, the fauna is very arctic in character, and that even
in the 52nd and 54th degrees of north latitude.”+ And if
we go back to earlier Tertiary times than the Crag period, we
find all the faunas—back to the very commencement of the
Tertiary formations—evidencing warmer and warmer climatic
conditions as we recede from the Glacial period. Nor is this
evidence confined to the faunas; it is perhapseven better illus-
trated if we trace the successive floras from the Eocene up-
wards to the Glacial period. Commencing with the Lower
Eocene we find in the London clay the fruits of numerous
palms, belonging to genera only now found in the tropics,
accompanied bythe custard apple, gourds, and melons. These
are followed intime by the Bournemouth beds, with subtropical
Proteaceze, numerous fig-trees, the cinnamon, and many
other plants and trees, reminding the botanist of parts of

* Philosophical Magazine, vol. xxxvi., page 380.
+ Principles of Geology, p. 199.

1874.] Climate of the Glacial Period. 435

India and Australia. In the Lower Miocene beds of Swit-
zerland, the flora of which has been wonderfully preserved on
the northern borders of the Lake of Geneva, there are still
species of fig, cinnamon, palm-trees, and other subtropical
vegetation, but with them appear species of poplar, horn-
beam, oak, elm, and other trees now characteristic of tem-
perate climes, which are absent from the European Eocene
strata, and which indicate a less tropical climate. These
beds are succeeded by the Upper Miocene strata of Géningen,
still containing many exotic genera, but with a still larger
proportion of species that betoken that the climate—though
still more equable and warm than at present—was gradually
becoming unsuitable for subtropical plants. Coming still
higher in the Tertiary series, we find in the Lower Pliocene
of Italy that most of the subtropical genera have disap-
peared, and when we reach the Newer Pliocene deposits the
trees and shrubs are those now chara¢teristic of European
forests, and suggest that the climate was similar to that
at present enjoyed in Europe. Then in England we find
the Newer Pliocene beds, with their trees and plants of
recent species, as in the Cromer Forest bed, followed by
lignite beds at Bure and Westleton, containing Salix
polaris, now only known within the arctic circle, and Hynum
turgescens, an arctic moss. M. Nathorst, a Swedish geolo-
gist, who has studied these beds, considers that there is a
gradual passage from the mild period of the forest bed, pro-
bably only a little colder than at present, to severe arctic
conditions. ‘These Bure and Westleton beds are succeeded
by the till and boulder clay of the Glaciai period.

If instead of the successive floras we follow the successive
faunas, the land animals or the marine, we have a precisely
similar succession of events, a gradual transition from
the tropical forms of the Eocene and the subtropical
ones of the Miocene through the more temperate species of
the Pliocene, up to the arctic shells and mammals that
usher in the Glacial epoch. The evidence is complete that
points to the gradual cooling of the climate, and there is
none whatever to show that there were any alternations of
cold and warm periods. It is exa¢tly the same kind of evi-
dence as we should have if we travelled from the tropics
along the coast of the continent of America northwards.
The plants and land animals on the one hand, the inhabi-
tants of the deep on the other, would gradually change
their character ; tropical forms would give place to sub-
tropical, these to temperate, and finally, when the far north
was reached, arctic species would predominate.

436 Climate of the Glacial Period. (October,

Mr. Croll has pointed out that though we have no evidence
to support his theory in the successive faunas and floras of
the Tertiary strata, yet in the Eocene beds of Switzerland
and the Miocene of the north of Italy there are conglome-
rates containing large transported blocks of stone. Fully
admitting that these were most likely transported by ice, I
need scarcely remind geologists that no marine remains
have been found with them, and that they were probably
deposited in lakes, for although the Miocene boulder beds of
Piedmont are more than roo feet thick they contain no
organic remains, and we know that this is a feature of
modern glacial lakes. The beds rest also on Lower Miocene
strata, mostly of fresh-water origin. To adduce such
isolated facts as proofs of the existence of Glacial periods in
Early Tertiary times is as logical as it would be to argue that
there is now a Glacial period in the tropics because there are
glaciers there. It is as if a traveller on the coast of western
tropical America, coming in sight of one of the snow-capped
summits of the Andes, should contend—although the sea
and the land teemed with tropical forms of life—that he was
in the arctic regions. Probably throughout geological his-
tory there never was a time when some mountain summits
did not rise above the limits of perpetual snow, and we may
expect to find in every geological formation some ice-borne
boulders, without being forced to conclude that it required
a Glacial period to transport them. The only safe guides to
follow are the fauna and flora preserved in the strata, and
even these fail us when we go far back in geological time,
for we know not what to call tropical and what temperate
forms; but so far as Tertiary rocks are concerned we may
accept their evidence, and they prove that there were no
oscillations between extreme heat and extreme cold, but a
gradual and continuous decrease of temperature from the
Eocene up to the Glacial period.

Coming to the Glacial period itself, what evidence have
we of the intercalation of that time of ‘‘ perpetual summer”
that is, according to Mr. Croll, a necessary consequence of
his theory? The fact most commonly appealed to, both on
the Continent and in England, in support of this supposition,
is the presence of seams of lignite in Switzerland—as at
Diirnten, in the canton of Zurich—resting on a great thick-
ness of boulder clay, and capped by beds of gravel with
large erratic blocks. These seams of lignite generally vary
from 2 to 5 feet in thickness, but in some parts swell out to
as much as 12 feet. I admit that the evidence is conclusive
that after the ice—during the great extension of the Swiss

1874.] Climate of the Glacial Period. 437

glaciers—had occupied the ground for a long period, it re-
treated, and peat mosses accumulated in low swampy spots ;
but I dispute that there is any evidence of a warm climate.
Cones of the Scotch and spruce firs, and leaves of the oak,
the ash, and the yew, have been found in these deposits,
and, as these are all of existing species, Prof. Heer has in-
ferred that the climate was similar to that now experienced
in Switzerland. In reality it may have been colder, for all
these trees range to more northern latitudes. The bones of
the large Mammalia found in the same deposits tell us
nothing of the climate, or, at the most, do not throw any
further light on the question than is derived from a study of
the vegetable remains. All that is proved is, that towards
the latter part of the glacial period the ice retreated, and
after a long interval advanced again, and covered some great
mosses that had accumulated during its retreat. We have
had a similar event, though on a smaller scale, in historical
times. M. Venetz has pointed out that before the tenth
century the Swiss glaciers extended further than they now
’ do, that then for four centuries they gradually melted back,
and then again began slowly to advance, and have been ever
since gradually regaining their lost territory. If this be so,
they must have passed over surfaces on which vegetation
grew during their retreat, and if these surfaces were again
uncovered we might find leaves of existing Swiss trees in
deposits between two sets of Moraine gravels, one of an
earlier and one of a later date than when the trees
flourished.

Mr. Croll has himself advanced, as a crucial test of his
theory, that as whilst one hemisphere was being glaciated
the other was enjoying an almost tropical climate, and that
as these conditions alternated several times during the
period of greatest eccentricity, we ought to find proofs of
the existence of these warm periods intercalated with those
of greatest cold. And the evidence we require is, not that
firs, oaks, and yews grew in Switzerland, as they do now, on
moraines, during a temporary retreat of the ice, but of spe-
cies that now live much further south, having then advanced
far northwards. In faét, we want evidence, such as we
have seen is so abundant in the Miocene strata, of a sub-
tropical fauna and flora having flourished in Europe in inter-
glacial times, and nothing less is satisfactory, according to
this theory. The periods of greatest heat are as necessary
a result of the theory as those of greatest cold, and they
ought to occur alternately.

I fully believe that if any one takes the trouble to read

VOL. IV. (N.S.) 3K

438 Climate of the Glacial Period. (October,

this paper, in future years, they will think many of
my arguments unnecessary and superfluous; but my con-
temporaries know what a large amount of acceptance this
theory has met with amongst our leading scientific men,
many of whom have adopted it as the true cause of the
Glacial period. What is required, therefore, at the
present time, is a thoroughly exhaustive examination of
it, and to the best of my ability I shall make it.
The most complete geological evidence is that of the
marine shells. They have been more certainly and abun-
dantly preserved than other organisms, and from the
earliest Tertiary epoch up to the present time we have an
almost continuous series illustrating the successive faunas,
and in the interglacial beds they have been much studied. I
shall now take the evidence that these last afford us into
consideration, and that nothing may be overlooked I shall
take my examples from the ‘‘ Great Ice Age” of Mr. James
Geikie, who is one of Mr. Croll’s most ardent supporters.
First of all, we may dismiss all the Scotch interglacial beds
as negatively hostile to the theory, as they either contain no
organisms at all, or—in a few cases—some shells of arétic
types; nowhere have more southern forms been found than
those existing off the present coasts. Coming to England,
we have the marine shells of the west coast interglacial
beds,—those found on Moel ‘Twyfaen, at Macclesfield, and
generally over South Lancashire. I have, in another
place, argued that these shells are of older date than the
Glacial period, and that they were pushed up out of the bed
of the Irish Sea by the great glacier that filled it;* but I
need not go into this argument here, as, whatever the evi-
dence may be worth, it is again hostile, and Mr. Geikie
admits that ‘‘ upon the whole the fossils indicate colder con-
ditions than now obtain in the [rish Sea.”t On the eastern
coast most of the shells that have been found indicate a
colder climate, but at Holderness a few fragments of more
southern species have been discovered. Messrs. Wood and
Harmer, who have described these deposits, admit that they
have been transported from some other area; and Mr. Croll
has himself, with great acumen, shown how they might have
been pushed up out of the German Ocean by the ice that
brought over blocks of stone from Scandinavia and thrust
them up on the same coast. However, whether brought by
currents of water, as suggested by Messrs. Wood and

* Nature, vol. x., pp. 25 and 62.
+t Great Ice Age, p. 362.

1874.] Climate of the Glacial Period. 439

Harmer, or by ice, as suggested by Mr. Croll, these broken
and fragmentary shells—mixed through other transported
material evidently ice-borne—are the débris of beds older
than those in which they are now found. The Foraminiferze
of the same deposits have been examined by Messrs. Cross-
key and Robertson: they, like the shells, are much worn,
and present a more arctic character, varied by the presence
of one or two Tertiary forms.* Altogether it appears that
the deposits have been formed by the mixing together of the
shells of two or more periods; and we might just as readily
infer an arctic climate from the artic shells and Forami-
niferee as a more southern one from the few fragments of
species characteristic of the coralline crag, and which
were probably derived from beds of that age in the neigh-
bourhood.

In Ireland the shells found in the drift also indicate a
colder climate than the present, and in Scandinavia the only
evidence of the warm periods of Mr. Croll’s theory, advanced
by Mr. Geikie, points in reality to the opposite conclusion ;
that is to say, beds in Scania, described by M. Nathorst,
containing Arctic plants—amongst others Salix Polaris, now
confined to the Arétic Circle,—which indicate a climate more

‘severe than that of Northern Norway. These and other
beds so far north are valuable, as evidence that the ice did
not destroy all remains of the vegetation that had flourished
in the so-called “‘inter-glacial period,’ and if during that
time more southern forms had ever advanced northwards
we ought somewhere to find their remains.

In North America there is, again, no evidence of a warmer
climate having prevailed in inter-glacial times; the marine
shells and the vegetable remains all point either to more
Arctic conditions, or to a climate not warmer than the
present.

But, even if we could bring ourselves to believe that all
the remains of the southern faunas and floras had been
destroyed by the ice of the Glacial period, whilst the more
Arctic forms had been preserved, we ought surely to find
some evidence of the warm climates to the south of the limit
to which the ice extended. In Sicily are preserved abun-
dance of memorials of the cold climate of the Glacial period,
when Alpine ice filled all the lakes of North Italy, covered
the plains of Piedmont and Lombardy, and cooled the waters
of the Mediterranean so that it was occupied by more

* Introduction to Crag Mollusca. By S. V. Woop, Jun., and F. W.
HarMer. P._22.

440 Climate of the Glacial Period. (October,

northern species of mollusca, such as Cyprina islandica and
many others. In Southern Sicily a magnificent series of
shells have been preserved in rocks rising 2000 feet above
the sea. Amongst the latest of these deposits, the northern
forms of mollusca appear, and they are nowhere accompanied,
followed, or immediately preceded by these tropical species
that we ought to find if Mr. Croll’s theory be true; to obtain
them we must go back to Early Tertiary times, to the Miocene
and Eocene periods. ‘These alternations of climate cannot
have taken place; it is not possible that all memorials of
Arctic faunas and floras in the Eocene and Miocene periods,
and all the remains of tropical species in the Glacial period
could have been destroyed, whilst in the former case the
southern forms, and in the latter the northern, were abun-
dantly preserved. And yet, strangely enough, we are told
by the advocates of this theory that it is in harmony with
geological facts. +

Coming down to post-glacial times, we have in the marine
shells only evidence of a gradual amelioration of the climate.
Some of the freshwater beds are, however, supposed to indi-
cate that, immediately after the Glacial period, a warmer
climate prevailed than we enjoy at present. They only,
however, show that it was a more Continental one, which is
in accordance with other facts indicating that the British
Isles were then joined to Europe by continuous land. I
have published my reasons* for believing that a great river,
into which flowed the waters of the Rhine, the Thames, the
Seine, and many other streams, ran southwards, through
what are now the Straits of Dover and the English Channel,
as far as, and possibly further than, the Bay of Biscay, ata
time when the level of the sea stood much lower than at
present. The ice of the Glacial period had then retired from
the southern portion of the bed of the German Ocean, but
the flow of the waters northwards was still stopped by it, or,
as I now think more probable, by the great moraines left
across the ocean bed by it. Mr. Godwin-Austen has, in his
various classical papers on the post-tertiary beds of the
British Channel, shown the great probability that the Straits
of Dover did not exist until after the Glacial period, but that
a neck or isthmus of land stretched across, joined England ~
to the Continent, and divided the German Ocean from the
English Channel. Now, at the height of the Glacial period,
we know that the greater part of the bed of the German
Ocean was filled with ice, that stretched from Scandinavia

* Nature, vol. x., p. 25.

1874. Climate of the Glacial Period. 441

to the coasts of Norfolk, if it did not extend further south.
At this time the southern part of the German Ocean bed
must have been occupied by a great freshwater lake whose
arms ran up the valleys of the Thames and other rivers.
The commencement of the cutting out of the Straits of
Dover was, I believe, caused by the overflow from this great
lake finding an outlet across the neck of land, which was
gradually worn down, and the beds of gravel mantling all
the lower hills of the Thames valley were, I think, beaches
formed at the successively lower levels at which the lake
stood. The ice to the north was now gradually receding,
and leaving great banks of moraine rubbish in the old ocean
bed, to be ultimately levelled by the sea when it long after-
wards returned, and which now form the Dogger and other
great submarine banks. At the highest point at which the
freshwater lake stood, and which marks the extreme rigour
of the Glacial period, we have no organic remains, but many
boulders in the beach deposits apparently transported by
coast ice. Lower down, the ice had retired a little to the
north ; the climate was still severe, but the mammoth, the
woolly rhinoceros, the musk-ox, the lemming, and other
animals fitted to live in an Arctic climate, left their remains
in the old beaches. Still lower, we find more southern
mammalia coming upon the scene, accompanied by fresh-
water shells, three of which are not found so far north. I
thought formerly that their presence merely intimated a
lowering of the lake in autumn, or that the ice had melted
so far back that it partly drained around Scotland; but, on
fuller consideration, I cannot believe that the hippopotamus
came up, or the Cyrena fluminalis permanently lived in, water
chilled by the melting of Continental ice; and I have come
to the conclusion that the ice must have retired so far back
that it drained entirely to the north of Scotland, and that it
had left a great moraine stretching across the ocean bed,
where the Doggerbank now lies, that closed the flow of the
southern waters northwards. The Straits of Dover, and
probably another barrier much further to the west, had by
this time been so far cut through that the rivers stood but
little above their present levels when the hippopotamus came
up them, possibly only in summer. Then, too, existed great
river conditions similar to those under which Cyrena flumi-
nalis now thrives in Cashmere and Africa. As some addi-
tional evidence in favour of this theory, I may add that one
of the three river-shells, Unio pictorum, has been dredged
off the mouth of the British Channel in the course of the
supposed great river.

442 Climate of the Glacial Period. (October,

On the continent of Europe, and in North and South
America, no evidence whatever has been found to indicate a
sub-tropical climate having prevailed in post-glacial times in
the temperate regions of the globe, and I cannot but consider
that the issue that Mr. Croll has based on the existence of
warm climates having existed about the same time as, and
intercalated between, his cold climates, must be given
against him. Ifso, it is fatal to his theory, for he has not
one whit exaggerated the importance of the necessity of these
oscillations of temperature. If the theory be true, each
hemisphere endured the extremes of heat and cold. Just as
much as the Glacial period lowered the temperature of any
place below what it is now, so must the warm period that
came on in about ten thousand years have raised it, and it is
a rigorous deduction from the theory that, either in the
southern or the northern hemisphere, or both, there must
have intervened a great period of warmth as great
as that of the Miocene epoch since the countries were
glaciated.

There are some other fa¢ts to be accounted for that are
not, I think, explained by Mr. Croll’s theory, but they will
be better understood if I take them into consideration under
the next theory to be discussed.

3. Theory of a Change in the Obliquity of the Ecliptic.—So
long ago as 1688, Dr. Robert Hooke drew attention to the
evidences of tropical climates having prevailed in Europe,
and speculated on changes in the axis of the earth’s
rotation, or a shifting of the earth’s centre of gravity, or a
change in the obliquity of the ecliptic. The last theory was
a favourite one amongst the older English geologists, but
even in these early days received little favour from as-
tronomers, for Newton pronounced against it and declared
that astronomy did not countenance the theory that there
had been any change in the direction of the earth’s axis.
The celebrated Laplace investigated the problem of the
effect of the attraction of the sun, the moon, and the
planets upon the equatorial protuberance, and came to the
conclusion that this could only cause a variation in the ob-
liquity to the amount of 1° 21’. More recently, Leverrier
has examined the same question, and has arrived at the
result that it might vary to the amount of 4° 52’, but not
more. ‘The difference between Laplace and Leverrier is a
large one, but most geologists have accepted their verdict as
decisive, that former great changes of climate could not
have been caused by variations in the obliquity of the
ecliptic.

1874.] Climate of the Glacial Period. 443

But granted that the great geometricians could not have
erred very much in their calculations, we may still, with-
out presumption, enquire whether there are not other ele-
ments of disturbance besides those they investigated.
They assumed in their examination of the problem that the
thickening of matter around the equator was a constant °
quantity, whereas there are evidences of great upheaval
and depression in remote ages that may have altered the
conditions of the question. The gradual heaping up of ice
around the poles in the glacial period must have in some
measure diminished the difference between the polar and
the equatorial diameters. Many physicists believe that
even now an elevation of land around the poles and a de-
pression of land in the tropics is taking place.

The protuberance around the equator is not a regular one,
but the equatorial circumference approaches in general
outline to an ellipse, of which the greater diameter is two
miles longer than the other. At the time the above-
mentioned calculations were made the data did not exist for
determining the irregularity. To the non-astronomical
mind it appears evident that this great difference in the
equatorial diameters is an element of great importance in
the calculations, and as it was not considered we cannot
admit that the problem has yet been decided. The great
preponderance of land in one hemisphere, not arranged
around the pole of the earth but in a mass whose centre is
situated near the English Channel, must also be a disturbing
element of no mean importance.

Our knowledge of the other planets teaches us that there
is no limit to the obliquity of their axes. In Jupiter the
axis is nearly perpendicular to its orbit, so that there is no
change in the length of its day. In Saturn the obliquity is
29, in Mars 303°, and in Venus it reaches the extreme
amount of 75°, so that its tropics overlap considerably its
arctic circle, and there are no temperate zones. The
original cause of the inclination of the axes of the planets
has never been demonstrated, and until this be done it may
be allowable to suppose that changes may occur through
the same cause.

Lieut.-Col. Drayson has approached this question in a
different manner.* Leaving out altogether the consideration
of the cause, he contends that a variation of the obliquity
is taking place. He shows that according to the observa-
tions of the last four hundred years the obliquity of the

* The Last Glacial Epoch. Chapman and Hall.

444 Climate of the Glacial Period. (October,

ecliptic has decreased, and argues that the pole of the
earth instead of describing a circle around the pole of
the ecliptic describes a larger one around a point six
degrees from that centre. It is admitted, and is indeed
an established fact, that the obliquity is less than it was
“some centuries ago, but the generality of astronomers are
agreed that this is owing to the small variation that the
calculations of Laplace and Leverrier showed to be possible,
and that it is simply a coincidence that the path described
by the pole is that of a larger circle around a point a little
distant from the pole of the ecliptic. They contend that
the pole of the earth does describe a circle around the pole
of the ecliptic as a centre, but that the outline of that circle
is a waved one, and that during the time that observations
have been made the direction of the pole has been down
towards the trough of one of these waves, but that it will
again rise as much above as it dips below the mean distance
from the centre. It is an obje¢tion to this theory as well as
to that of Lieut.-Col. Drayson that it is assumed that the
pole of the earth describes a circle, whereas amongst the
heavenly bodies we have no circular movements. All the
orbits are ellipses of varying eccentricity, and from analogy
we should be led to expect that the pole of the earth would
not describe an exact circle. That it does so is entirely
theoretical, founded on calculations based on the assump-
tion that the earth’s equatorial circumference is a circle,
which it is not. Lieut.-Col. Drayson has informed me that
though he has assumed the curve to be that of a circle, the
earlier observations cannot be sufficiently relied on, and it
may be that of an ellipse or of a spiral.

Until astronomers have re-considered this question with
the light of our present knowledge of the figure of the
earth, geologists should not be prevented from speculating
on the possibility of great changes in the obliquity of the
ecliptic having caused former great variations of tem-
perature. According to Lieut.-Col. Drayson, the obliquity
of the ecliptic has been as much as 353. ‘The effect of this
was, he urges, the production of the Glacial period. He
states that as the arctic circle would then reach nearly to
latitude 543°, there would be an accumulation of snow
during the winter; which during the summer, in consequence
of the great altitude of the sun, would be melted nearly to
the poles, occasioning enormous floods. Now if this really
would be the effect of a greater obliquity of the ecliptic, we
might at once dismiss it as a possible cause of the accumu-
lation of ice in the glacial period, for it is evident that the

1874.) Climate of the Glacial Period. 445

great mass of ice—some thousands of feet thick—that
moved down southwards over the northern parts of America,
Europe, and Asia, could not have been the production of a
single winter. It is possible that this and some other
geological speculations of the author have prevented many
from taking a favourable view of his theory, and it is of
importance to discuss what would be the real effect of a
greater obliquity of the ecliptic.

We are able to approach this question provided with
data derived from the effeCis of the present inclination of
the axis of the earth to the plane of its orbit. To it is due
the varying length of the day throughout the year in the
temperate and arctic zones, and the consequent production
of theseasons. If the axis, as in Jupiter, were perpendicular
to the plane of the orbit, night and day throughout the
world would be equal. Every day there would be twelve
hours’ light and twelve hours’ darkness. Each place would
have but one season, and eternal spring would reign around
the arctic circle. Under such circumstances the piling up
of snow, or even its production at the sea-level, would be
impossible, excepting perhaps in the immediate neighbour-
hood of the poles, where the rays of the sun would have
but little heating power from its small altitude.

Our summer and winter are therefore due to the present
obliquity of the ecliptic, and so also is it that now around
the poles some lands are being glaciated, for excepting
for that obliquity snow and ice could not accumulate,
excepting on mountain chains. The obliquity of the
ecliptic does not affect the mean amount of heat received
at any one point from the sun, but it causes the heat
and the cold to predominate at different seasons of the
year. Near the poles there are six months’ night and
six months’ day, but the absolute amount of heat that
arrives from the sun is the same as if there were twelve
hours’ light and twelve hours’ darkness every day. The
cause of perpetual ice and snow is not, as I have already
shown, the cooling of the air by the melting snow in
summer, nor the formation of clouds shutting off the rays
of the sun. It is, I believe, in consequence of the reflection
into space of many of the rays of light and heat that fall
on a snow-covered surface, and any cause that tends to
increase the amount of snow or to extend the snow-covered
area will tend to chill the climate of such parts by occa-
sioning more of the rays of the sun to be deflected and lost.
Therefore a long hot summer and a long cold winter are
more likely to favour the accumulation of perpetual snow

VOL. IV. (N.S.) 3k

446 Climate of the Glacial Period. (October,

than a place under exactly the same conditions, where a
thermometer exposed to the rays of the sun would register
the same amount of heat received, but where the sun rose
and set every twelve hours, so that the heat by day and the
cold by night were never so excessive.

Thus, if we suppose the earth’s axis to have been
originally perpendicular to the plane of its orbit, so that it
had twelve hours’ night and twelve hours’ day all over the
world, and that from some cause or other the axis began
to incline and the inclination gradually to increase, the
seasons of the year in the temperate and arCtic zones would
tend to become more and more distinét. An ever-widening
circle around the poles would be covered by snow during
the cold winter, and lower the temperature of the summer
by reflecting the rays of the sun as long as it lasted; and
if the obliquity increased to a greater amount than at
present, so would a greater area be brought under aré¢tic
conditions, and an approach be made to the cold of the
Glacial period.

The accumulation of snow is dependent on another faétor,
namely, increased precipitation ; and I doubt if any theory
would satisfy the conditions of the case that simply increased
the cold of the glaciated regions without providing for an
increased evaporation outside these regions, and thus to
allow greater precipitation upon them. An increase of the
obliquity of the ecliptic satisfies this condition, for whilst
on one hand the ar¢tic circle would be extended, so on the
other would the tropics; one part of the temperate zones,
that next the poles, would have its mean temperature
greatly lowered; whilst the other, that nearest the equator,
would have its temperature raised and become an evapo-
rating area. Thus, supposing Lieut.-Col. Drayson to be
right in his theory, that at one time the obliquity was
as much as about 353°, the arc¢tic circle would then reach
to latitude 543°, and the tropics to 353°, reducing the
temperate zones from their present width of 43° each to
only 19°, one-half of the decrease being added to the arétic
circle and one-half to the tropics. As soon, also, as the
ice had extended so far as to shut off the warm currents
of the ocean that penetrate nearly to the pole, much
of the heat now spent in melting the ice of the ar¢tic circle
would be expended in evaporation, and precipitation would
be proportionally increased.

Those who have followed me in this short argument will,
I believe, admit that an increase of the obliquity of the
ecliptic does appear to be sufficient to cause an addition to

1874.] Climate of the Glacial Period. 447

the snow andice piled up around the poles; and we may now
inquire if the theory throws any light on other problems of
the Glacial period, and is in harmony with the facts of
geology. In doing this I shall contrast it with the other
cosmical theory. The theory of the greater eccentricity of
the orbit requires that the glacial periods of the two hemi-
spheres should be at different times; that of the greater
obliquity of the ecliptic, that they should be simultaneous.
There is not much evidence available, but what little there is,
is in favour of the glaciation of the two hemispheres having
occurred at the same time. Thus, there exist glacial con-
ditions at present around the poles, due primarily to the
obliquity of the ecliptic, and these conditions are contempo-
raneous in the two hemispheres. More ice and snow is
heaped up within the antarctic circle than at its antipodes,
because a greaterevaporating area of ocean surroundsit, whilst
the arctic regions are almost circled by land that not only
lessens the evaporating surface, but intercepts much of the
moisture-bearing currents from the south. The snow piled
up on the Himalayas, the Alps, and other high northern
ranges, is just so much prevented from reaching the arétic
regions. That the difference is due to lessened precipitation,
and not to a difference of temperature, will be seen if we
follow the isotherm of 30° around each hemisphere. We
shall find it deviating but little in the southern hemisphere
from the line of lat. 60°, being now a little to the north and
now a little to the south of it. In the northern hemisphere
the isotherm of 30° is much more irregular, sometimes
running far to the south, sometimes far to the north, but
the mean is again about lat. 60°, proving that if there was
as much precipitation there would be as much ice and snow
fo the north of lat. 60° N. as there is to the south of
lat. 60° S. Even now, if all the snow of northern mountain
ranges was added to that existing to the north of lat. 60° N.,
the difference would be greatly lessened, and we should
have in both hemispheres a partial Glacial period reaching
nearly 30° from the poles, and produced by the present obli-
quity of the ecliptic. Only on one of the other planets has
an accumulation of snow at the poles been proved to exist,
namely, on Mars; which, with an obliquity of 303°, is glaci-
ated at both poles at the same time. So that, judging from
analogy, we might expect the glacial period of the two
hemispheres to have been contemporaneous.

Many plants and some animals are found, in both the
northern and southern temperate zones, separated by the
whole width of the tropics, which they cannot now pass;

448 Climate of the Glacial, Period. (October,

and Mr. Darwin has explained their presence by supposing
that during the glacial period they were driven to the high
lands of the tropics by the advancing ice, and that on its
retreat they followed it north and south. A glacial period
in one hemisphere only would not afford this means of mi-
gration; the plants and animals driven south by the
northern ice would always have a hot zone to the south of
them, which they could not pass.

Another class of evidence that favours the theory of the
glacial periods of the two hemispheres having existed at the
same time, is that connected with the lowering of the sea-
level. Mr. Alfred Tylor, some time ago, advanced the
theory that the piling up of ice in the northern hemisphere
would lower the level of the ocean 600 feet. Mr. Croll has
lately discussed the question,* and comes to the conclusion
that, if each hemisphere was glaciated alternately, the level
of the ocean would be raised, and not lowered, in the one in
which the ice accumulated ; by the melting of the ice of the
opposite pole and the shifting of the centre of the earth’s
gravity towards that covered by an ice-cap. Though I can-
not agree with Mr. Croll’s estimate of the thickness of the
ice, and think that it could not possibly have been highest
at the pole, I have no doubt that a great lowering of the
level of the ocean could not have arisen by the accumulation
of ice at one pole, if at the same time that now existing at
the other was melted off. But if the glacial periods of the
two hemispheres were simultaneous, the water abstracted
from the sea and frozen into ice at the two poles, and that
impounded in the great lakes of Northern Europe, America,
and Asia, by the blockage of the northern drainage of the
continents by ice, must have lowered the level of the ocean
to a great extent.

In my “ Naturalist in Nicaragua” I stated that this de-
crease in the volume of the ocean could not have been less
than 1000 feet. I was thus guarded because we had at that
time no proof of the ice having descended from the north
upon Northern Asia, and there was no certainty that the
Polar basin had been filled with it. Since then I have my-
self found evidence in Siberia that the Arctic Sea was filled
with ice, which was piled up so high that it overflowed the
low lands as far as lat. 52° N. Calculating from this data,
I find that the lowering of the sea-level—on the supposition
that the ice was equal in the two hemispheres at the same
time—could not have been less than 2000 feet, and may

* Geological Magazine, July and August, 1874.

1874.] Climate of the Glacial Period. 449

have been much more. A glacial period in one hemisphere
only would not produce this result, and therefore any
evidence that tends to prove that the level of the ocean
was greatly lowered in the glacial period is also evidence
in favour of the northern and southern ice having been
contemporaneous.

Overthe whole world the distribution of manyinsular faunas
and floras has been explained by the supposition that the
islands were at one time joined to continents near them and
to each other, in post-tertiary times. In every case that I
have examined, the theory is that the last movement of the
land has been one of depression. ‘Thus the land over which
the flora of Greenland reached that country from Eurcpe is
supposed to have sunk down. The lands connecting
England with Ireland and the Continent, during the forest
periods before and after the culmination of the glacial
epoch; the land connecting Malta with Africa; that joining
the Islands of the Malay ‘Archipelago on one side to Asia,
on the other to Australia; that connecting the West-Indian
Islands with Venezuela and Yucatan; and that uniting
Tasmania with Australia,—are all supposed to have been
submerged by a sinking of the land, and we have in the
same areas no corresponding instances of elevation. Whilst
all islands having shallow channels, however broad, sepa-
rating them from each other and from not distant continents,
produce evidence of having been formerly conne¢ted in post-
tertiary times, on the other hand islands surrounded by deep
water are distinguished by peculiar faunas. Thus Mada-
gascar is separated from Africa by a deep sea, and its fauna
is wonderfully distinét, though it still shows traces of a
geologically remote connection with that continent. The
Gallapagos Islands are a still stronger case, for though near
together they are separated by channels of great depth, and
Darwin found them tenanted by distin¢t species of reptiles,
birds, and plants. If the channels were made dry land, by
- the lowering of the sea, we easily understand why islands
surrounded by deep water did not lose their insular cha-
racter ; but on the supposition that they have been produced
by movements of the land, the reason is not obvious why
the depressions should have been limited to a certain depth.

All round the British and Irish coasts, and around
Western Europe, we have submerged forests passing under
the bed of the ocean. Some—as that at Cromer—are older,
others newer, than the greatest development of the ice of
the glacial period. To allow these forests to have grown,
we have to suppose an elevation, and for their submergence

450 Climate of the Glacial Period. (October,

a depression, of the land,—on the theory that it was move-
ments of the earth’s crust that brought it above and sank it
below the sea. Now, in various places in the south of
England, we have marine deposits a little older than the
forest bed of Cromer: they occur mostly between the present
tide-marks,—never higher than we may suppose the tide to
have reached before the Straits of Dover were cut through.
Therefore, if the surface of the land has oscillated, it is re-
markable that it should have returned to the same level as
it stood at before the Glacial period; but such a fact is
clearly in unison with the idea that it was the mobile water
that had retreated and returned. These submerged forests
are not confined to Europe, but are found on the coasts of —
America,—as in the Bay of Fundy,—betokening that their
occurrence belongs to a general and not to a local cause.

Another class of phenomena, usually ascribed to a gradual
sinking of the earth’s crust, but which might also be pro-
duced by the return of the sea to he level it stood at before
the Glacial period, is that connected with the growth of
coral islands. Darwin’s celebrated essay on their formation
first proved that they were due to the gradual deepening of
the water. Dana, closely following Darwin in his theory,
estimates that this deepening of the ocean bed from which
the coral islands rise has been at least 3000 feet, and that
the subsidence to which he ascribes it extends round one-
fourth of the earth’s circumference in the Pacific, being
indicated by atolls in that ocean for 6000 miles in length
and 2000 in width. In the Atlantic he considers that “‘ the
Bahamas show by their form and position that they cover a
submerged land of large area, stretching over 600 miles
from N.W. to S.E. The long line of reefs and the Florida
Keys trending away from the land of Southern Florida are
evidence that the Florida region participated in the down-
ward movement.’’*

Nor are these indications of either a subsidence of the
land or a rise of the level of the ocean since the Glacial
period yet exhausted. C. F. Hartt considers he has found
proofs in Brazil that that country stood higher when it was
glaciated than it nowdoes.t Dana has argued the same
respecting the high latitudes of North America. There is
hardly a mountain chain of the world that has not been
supposed to have stood higher, to account for the lowering
of the snow-level on its sides in the Glacial period. The
Himalayas, the Alps, the Caucasus, the Pyrenees, the

* Coral Islands, 1872, p. 366.
+ Geology and Physical Geography of Brazil. By C. F. Hartt. P. 573.

1874.] Climate of the Glacial Period, 451

mountains of Syria, the Atlas Chain, the mountains of New
Zealand, of California and Central America, and many
others, show distinct traces of glaciers having descended
either on ranges where snow now never accumulates or even
falls, or else thousands of feet below the present snow-line.
It has by some been considered a simple explanation of these
facts, to suppose that each mountain chain was elevated a
few thousand feet in the glacial period, and has since sank
down. Here the land went up and here it went down, they
say, and think they have found a solution, without explaining
why it should or how it could have done so. I shall have
some more remarks to make on this assumed elasticity of
the earth’s surface, but now pass on to remark how a general
lowering of the sea-level would cause the snow-line to
descend on every mountain chain. Mr. H. W. Bates has
pointed out to me, what seems perfe¢tly obvious when once
noticed, but what had certainly not occurred to me when I
first wrote on this subject, namely, that a lowering of the
sea-level would produce the same effect upon the climate of
any place as arise of the land to about the same amount
as the atmosphere would sink with the sea. I find that
Humboldt, in whose writings are found the germs of many
later theories, had made the same observation.* I fail to see
how glaciers could be produced in the tropics on mountain
chains far below the present snow-line in the Glacial period
if it was caused by an increase in the eccentricity of the
orbit ; for that could not affect the mean temperature of the
tropics where day and night were equal, and the heaping up
of ice at one pole could not lower the sea-level much; but
if it was caused by an increase of the obliquity of the
ecliptic, the mean temperature of the tropics would be
lowered through the path of the sun being lengthened, the
snow-line would descend still farther by the lowering of the
sea, and stili farther from increased precipitation, owing to
the greater evaporation that would take place when the
shallowing of the sea shut off cold currents from the polar
regions. The combination of these factors could not fail to
lower the snow-line in the tropics thousands of feet, as we
find it to have been lowered in the Glacial period.

The examination of the deltas of the great rivers—the
Mississippi, the Ganges, the Nile, and the Po—have shown
that there are land-surfaces and freshwater deposits hundreds
of feet below the level of the sea. All our English rivers run
in old channels now filled up nearly to low-water line, but

* Edinburgh Philosophical Journal, vol, iv., p. 267.

452 Climate of the Glacial Period. (October,

which are excavated in the solid rock for hundreds of feet
below it. These all prove that either the land stood higher
or the sea lower, and I cannot but agree with Mr. Alfred
Tylor, who has ably discussed this question, that the cause
is not a local one, but a general lowering of the level of the
ocean all over the world in Glacial times.

To these many evidences of a rise of the level of the sea
produced by the melting of the ice of the Glacial period, I
think I may fairly add the traditions of mankind of one or
more great deluges that overwhelmed peopled lands. In
America, Africa, and Asia the remembrance of great cata-
strophes that nearly exterminated mankind in certain regions
has been handed down, indistinétly it is true, but with a
marvellous resemblance in the traditions preserved in
countries of the world far removed from each other. Here,
again, I think that such a general explanation as that of the
rise of the waters of the ocean submerging low-lying peopled
countries—accompanied by earthquake convulsions, such as
were likely to be occasioned by the strains on the earth’s
crust when the ice melted off the mountain tops and the
polar regions, and ran down to the ocean beds—is a more
likely theory than that the traditions refer to local cata-
strophes.

We have proofs that man existed even in England before
the presumed date of the return of the waters of the ocean,
When the great lake that I have mentioned filled the southern
part of the bed of the German Ocean, whilst the northern
part was still occupied by the retreating ice, man appears on
the margin of that lake when it stood about two hundred
feet above the present sea-level. He follows its receding
shores as the great river running from it cuts through the
barriers in the English Channel, and throughout its gravelly
beaches his flint implements are found along with the bones
of the great mammalia. ‘The lake is gradually lowered until
the rivers running into it stand only about twenty feet above
their present level, and the hippopotamus and other southern
mammalia now come up the great river occasionally ; then
paleolithic man, and the great mammalia on which he
possibly subsisted, disappear together, and the waters of the
sea occupies the bed of the German Ocean and the channel
of the great river. Not from such rude tribes was, however,
the story of the great deluge handed down; but during the
Glacial period a belt of higher civilisation seems to have
girdled the world on the borders of the northern tropic, and
it was probably the remnants of ruined and engulphed king-
doms of that zone from which the traditions have come down.

1874.] Climate of the Glacial Period. 453

Mr. A. G. Renshaw has pointed out to me that the melting
of the ice of the Glacial period must have occupied thousands
of years, and I am quite convinced that it must have done so.
The gradual growthof coral islands, and the silting up of deltas
filled with fresh-water deposits, cannot be explained if we
adopt the hypothesis that the ice was suddenly melted. But
we do not require thousands or even hundreds of feet of sub-
mergence to overwhelm low-lying tra¢ts of country, and I
think we may fairly assume that there would be some sudden
rise of the sea-level, scores of feet at least, through the rapid
melting of great quantities of ice, as, for instance, when the
warm ocean currents from the south first gained access to
the Arctic regions, or when the immense fresh-water lakes of
northern Europe and Asia, pounded back by the ice, broke
through their melting barriers and ran down to the ocean.
Marine deposits found alternating with land surfaces in the
deltas of the Mississippi and the Po indicate such occasional
more rapid advances of the sea. It may be said that I am
advancing one theory—that of the lowering of the sea-level
during the Glacial period—to strengthen another—that of
the production of the Glacial period by an increase of the
obliquity of the ecliptic ; but the lowering of the sea is more
than theoretical,—it is a necessary consequence of the heaping
up of ice around both poles at once, and any evidence that
it was greatly lowered in Glacial times is also evidence in
favour of the theory of the increase of the obliquity of the
ecliptic, which would produce a Glacial period in the two
hemispheres at the same time.

Whilst we have thus many indications of a general rise of
the sea-level since the culmination of the Glacial period, we
have a remarkable eseeE HOR in arise of land towards the
north and south poles, which is believed to be still in
progress. In the southern hemisphere it is certainly still in
operation at intervals in the southern extremity of South
America and in New Zealand. In the northern hemisphere
it has been better observed on account of the greater amount
of land around the polar regions. One line of elevation
commences in Scandinavia at Stockholm on the eastern, and
near Gothenburg on the western, coast, increasing north-
wards as far as the North Cape, where there are marine
_ post-glacial deposits 600 feet above the sea. The land has
been elevated since the Glacial period, for the raised beaches
everywhere rest on the boulder clay with transported blocks.
Professor Kjerulf, of Christiania, has shown that the highest
sea-terraces contain Arctic shells, which indicate that the

VOL. IV. (N.S.) 3M

454 Climate of the Glacial Period. (October,

movement of elevation had commenced when the waters were
much colder than now.* ‘This movement appears to be
continued eastward round the Arétic sea, for, according to
Wrangel, the land is slowly rising around the northern
extremity of Siberia. He notices the occurrence of marine
beds containing sea-shells of existing species along with the
remains of the mammoth several feet above the sea-level.
There is some evidence that the coasts of Scandinavia are still
rising.

Another line of elevation runs north from near New
York. At Brooklyn the sea-beaches with marine shells
occur 100 feet above the sea. ‘This elevation also increases
northwards. At Quebec and Montreal it reaches between
400 and 500 feet, and much farther to the north within the
artic circle, on the shores of Barrow’s Straits, it has carried
up sea-shells of existing species to a height of 1000 feet above
the ocean. The movement clearly increases towards the
pole. How far it extends westward I do not know, but it
decreases eastward from Montreal, and in Nova Scotia I
could find no traces of any elevation having taken place.

Against these numerous instances of upheaval we have in
northern regions the solitary instance of a depression of
part of the coast of Greenland believed to be still in progress;
and it is avery suggestive fact that that country is at present
enduring intense glaciation and buried in snow and ice piled
up mountains high upon it. Seeing, then, that towards
both poles, with a single exception, there has been a rise
of land, in some parts still going on, in all evidently ac-

complished since the Glacial period, it is an important

enquiry whether the land so raised was above or below the
level of the sea in pre-glacial times. Within the arétic
circle the evidence is clear that it was not, for nowhere have
Tertiary marine shells been found. Nor can it be argued
that they may have existed, but have been destroyed by the
ice of the Glacial period, for Tertiary land-surfaces and land-
plants are abundant and well preserved. ‘This points to the
conclusion that like Greenland at present the land around
the poles sank down after it was covered by ice, and has
been slowly rising since it melted away. It is a legitimate
speculation, and one fully warranted by the facts of the
case, that the cause of the depression was the piling up of
a vast weight of ice around the poles, and the cause of the
elevation the removal of that vast weight by the melting of
the ice. That the movement of elevation continues in some

* The Terraces of Norway. ‘Translated from the Norsk by Dr. MARSHALL
HALL.

~~

1874.] Climate of the Glacial Period. 455

places only shows that the earth is a rigid body and but
slowly gives way to great strains. We must, according to
Mr. Croll’s theory, go back 200,000 years for the height of
the Glacial period; but not much more than one-tenth of
that time would be sufficient according to the theory of an
increase in the obliquity of the ecliptic; and I submit that
the shorter interval is more in accordance with the con-
tinuance of the polar movements, the facts connected with
the progress of civilisation northwards, and the little change
there has been in the fauna and flora of the world since the
Glacial period.

If our Glacial period was merely the heaping up of ice and
snow around the North Pole that now exists on both hemi-
spheres, the result would only be a slight shifting of the
centre of gravity of the earth northwards; but if it was
‘contemporaneous in the two hemispheres, as would result
from a greater obliquity of the ecliptic, the figure of the
earth would be changed, its polar diameter would be
lengthened, its mean equatorial diameter shortened, and
a series of strains would be set up tending to restore its
figure of equilibrium. And if during the Glacial period the
shape of the earth had approached that of equilibrium
through the sinking down of the land around the poles and
the rising of land in the tropics, then, when the ice melted
away, the polar diameter would be shortened, the mean
equatorial diameter lengthened, and forces would be set in
operation, tending to Jower the land of the tropics, and
raise that around the poles. Therefore I am ready to admit
that some part of the deepening of tropical oceans as
evidenced by the growth of coral islands and reefs—and
especially any now going on—may be due to a sinking of the
bed of the ocean; but in doing so I by no means admit that
the whole or even the greater part of the 3000 feet or more of
depression that has taken place, according to Dana, can be
ascribed to that movement. Butthe whole of the deepening
of the sea, both that arising from its surface being raised, and
that by portions of its bed being depressed, has, I believe,
been caused by the gradual melting of the ice of the Glacial
period, liberating the water that had been piled up at the
poles, and disturbing the equilibrium of the figure of the
earth.

I know that eminent physicists ascribe the movements
of the earth’s surface to its contraction from secular cooling,
and Mr. Mallet has lately ably argued that volcanoes are
one of the results of the movement due to that contraction.
Without wishing to call in question any theories about the

+50 Climate of the Glacial Period. (October,

earth having once been ina state of fusion, I can find nothing
to warrant the conclusion that for long geological ages it
has cooled in any appreciable degree. Laplace, reasoning
from astronomical observations made in the time of Hip-
parchus, calculated that during the last 2000 years there has
been no appreciable contraction of the earth by cooling, for
the length of the day has not been sensibly shortened, not
even to the amount of 1-300th of a second, so that the con-
traction of the globe must have been inappreciably small or
none at all, as it could not take place without affecting the
length of the day. We may therefore ask how an amount
of contraction inappreciable in 2000 years can have resulted
in the great amount of movement of the earth’s crust and
the vast volcanic energy now apparent, or why should its
tendency be to lengthen the polar and shorten the equatorial
diameters ? and are not such movements more in accordance
with the cause I have suggested ?

It is true that the earth must radiate heat into space; but
it is not evident that it radiates more annually than it re-
ceives from the sun, and if it does not it is not a cooling
globe. If earthquakes and volcanoes are the result of move-
ments of the earth’s crust—produced, not by contraction,
but by the strains set in action by the melting of the ice
caps of the Glacial period—so probably is what we call the
internal heat of the earth increasing in depth in our mines.
The usually accepted theory that the increased temperature
in depth is due to a greatly heated or even fluid fused nucleus,
slowly giving off its heat towards the surface, does not explain
the irregular distribution of the heat. To my mind it is
much more conceivable and more probable that the centre of
the earth is as cold as space, and that the movements of its
upper strata and the heat they give rise to are confined to
a comparatively shallow envelope, say not more than 500
miles thick.

The insufficiency of the theory of central heat was strongly
impressed upon me when I was studying the facts connected
with the frozen soil of Northern Siberia. At Yakutsk the
soil—excepting a few feet at the surface which is thawed
every summer—is permanently frozen to a depth of about
400 feet. This frozen soil extends to the shores of the Arctic
Sea, and in many places the cliffs bordering the rivers are
composed of alternate layers of soil and ice. It is in these
cliffs that the bodies of the Arétic rhinoceros and mammoth
have been found with their flesh still preserved. As Lyell
as remarked, since they were entombed, the soil cannot have
thawed for a single season or their flesh would have

1874.] Climate of the Glacial Period. 457

putrefied. The ice, therefore, is as old as the close of the
Glacial period, at which time these great quadrupeds
flourished, and at Yakutsk has remained unmelted all that
time. It seems impossible that it could have done so to a
depth of 400 feet from the surface if the earth was a cooling
globe. If, however, the heat of the crust of the earth is due
to movements within it, we can understand that in Siberia
it may not have been developed to the same extent as in other
parts; for, according to the researches of Murchison, that
country is situated on an area of great geological stability.
According to Von Cotta, it was never below the level of the
ocean from the close of the Permian epoch up to the Glacial
period; and I have been able to determine that this perma-
nence of level has continued up to the present time, and that
the strata of the Steppes are fresh-water deposits, excepting
those round the extreme northern extremity of the country.

If, whilst accepting Mallet’s ably worked out theory that
volcanoes are the result of movements of the crust of the
earth, I am right in ascribing these movements—not with
him to the secular cooling of the globe—but to the forces
tending to restore the equilibrium of the earth’s figure,
disturbed by the accretion of ice at the poles during the
Glacial period and its subsequent liquefaction, it will add
another to the many wonderful effects due directly and
indirectly to the action of the sun. It was the heat of the
sun that raised the water by vapourisation to the level at
which it congealed near the poles; and after the earth had
approached its normal form by the sinking of polar lands,
it was the heat of the sun that disturbed the equilibrium
again by melting the snow and ice and allowing it to flow
towards the equator. Not only volcanoes but the folding
of strata might be produced by these movements of elevation
and depression ; but I guard myself against expressing an
opinion whether or not the earlier and greater geological
folds and upheavals might not be due to other causes.

I have now brought forward a great variety of evidence,
drawn from very different sources, that points to the probability
of the Glacial periods of the two hemispheres having been
contemporaneous. Of the two astronomical theories it is
in favour of the one founded on a great increase in the ob-
liquity of the ecliptic, for that would cause a heaping up
of ice around the two poles at the same time. I shall now
turn to the consideration of a most important class of facts
only incidentally alluded to in the foregoing pages.

We have not only to account for the cold of the Glacial
period, but for its converse—the heat of Early Tertiary times.

458 Climate of the Glacial Period. (October,

The same latitudes that in the era of greatest cold were
covered with continental ice, or bore just beyond the reach
of the great glaciers the stunted Polar willow and a few
Arctic mosses and lichens, where the musk-ox and the
Greenland iemming found their northern limit in summer,
were at the commencement of the Tertiary period covered
with subtropical forests. Palm-trees—of types now restricted
to the Moluccas, the Phillippine islands, and Bengal,—with
custard-apples, melons, and many another tropical and sub-
tropical plant, flourished in the neighbourhood of Paris and
London. Huge animals, resembling but larger than tapirs,
roamed in these forests; monkies chattered amongst the
trees; great tortoises crawled beneath the rank herbage;
sea-snakes, crocodiles, and enormous sharks tenanted the
waters. If any of the mammalia had at that time become
adapted to live in an Arctic climate, they must have retired
to the very Pole to find it.

It is these two extremes of heat and cold with which we
have to deal. If we confine ourselves to the attempt of
accounting for the cold of the Glacial period alone, we
grapple with but half the problem. The climate of the
Eocene period was apparently as much warmer as that of
the great ice age was colderthan the present. The converse
of the cause of the one extreme in all probability produced
the other. It has been my fortune in other branches of
enquiry to find in one hemisphere the solution of a question
that had puzzled me in another. For instance, the origin
of large masses of gold in the gravel-beds of Australia, in
distri¢ts where the auriferous lodes contained only fine grains
of gold, remained doubtful until I found nearly at the anti-
podes of the first observation, in Nova Scotia, that the very
highest parts of the lodes had in some cases been left un-
denuded, and that there the gold occurred in large pieces,
whilst deeper only fine grains were found. ‘The conclusion
was obvious that in Australia the tops of the quartz veins
containing the ‘‘nuggets” had been worn off and carried
down into the valleys. And so, in studying the Glacial
question, it was not until I occupied myself with the con-
sideration of its antipodes, the climate of Early Tertiary
times, that I laid hold of facts that left in my mind little
doubt as to what had been the prime cause of the great
oscillations of temperature.

When the subtropical fauna and flora lived in Central
Europe as far as 52° N. lat., still nearer the Pole vegetation
flourished similar to that which now characterises the milder
portions of the temperate zones, and the representatives of

1874.] Climate of the Glacial Period. 459

the present flora of Northern Europe lived and throve within
about 11° of the Pole. Thus at Spitzbergen, far within
the Arctic Circle, in lat. 78° 56’, flourished species of hazel,
plane, poplar, lime, and beech trees, and Professor Heer
considers that firs and poplars must at that time have
reached to the North Pole if there was land there then for
them to grow on.

The strata in which this fossil flora is found within the
Ar¢ctic Circle are believed by geologists to be of Miocene age.
This determination is based on the fact that of 137 species
of plants found in the Greenland beds, 46, or one-third, are
identical with species of the Miocene flora of Central Europe.
This fact, however, seems to me rather to be in favour of-
the different age of the two deposits. It is improbable
that so many species should have had such a wide range.
We have seen that in the Eocene period Central Europe
was occupied by a subtropical fauna and flora. Is it not
likely that the time of the greatest heat in Europe was
also the time of greatest heat within the Arctic Circle, and
that, on the advent of the cooler climate of the Miocene,
some of the species that had lived much further north
migrated southwards into Central Europe, and took the
place of the Eocene flora, for which the climate had then
become too cool? In correlating the age of the arctic flora
with that of the Miocene of Central Europe, we may be
making the same mistake as future geologists would do if
they assumed that the beds lying above the Cromer forest
lived at the same time as some arctic ones now forming
because they contain the same plants, yet the former beds
were deposited at the very commencement of the Glacial
period. JI amnot sure that the omission of the consideration
of the important part that the varying climates of the
Tertiary period played in causing the faunas and floras to
migrate from one latitude to another may not have led to an
exaggerated opinion of the great length of time occupied in
forming the strata. It matters not, however, for my argu-
ment whether the arctic flora, of which we have such
abundant remains, was of Miocene or Eocene age. What I
have to say has nothing to do with the existence of the
same species at the same time in Central Europe and in
North Greenland, but with the fact that such plants were
able to live at all so far north. To avoid any mistake I
prefer, however, to speak of them as Early Tertiary.

In a paper on the Miocene flora of North Greenland read
before the British Association in 1866, Professor Heer
mentioned that more than sixty different species of plants

460 Climate of the Glacial Period. (October,

brought from Atanekerdluk, North Greenland, situated in
lat. 70° N., had been examined by him. Amongst the trees,
the most abundant is the Sequoia Langsdorfit, the nearest
living ally of which is the Sequota sempervirens, not now found
farther north than lat. 53°, and which requires a mean annual
temperature of at least 49° F., and that in winter the thermo-
meter should not fall below 34° F. Cones of a magnolia
have been found, proving, as Lyell has remarked, that this
splendid tree not only lived, but ripened its fruit within the
Arctic Circle. Vines also ‘‘twined round the forest trees,
and broad-leaved ferns grew beneath their shade.’”* Some
of the trunks of trees:observed were thicker than a man’s
body, and one seen by Captain Inglefield stood upright as it
had grown.

Nor, as we have seen, did this Early Tertiary flora end in
Greenland, but is found, containing a large number of species
of trees, in Spitzbergen, in lat. 78°56’ N., or about 11° from
the Pole. Prof. Heer considers that the winter temperature
in Greenland could never have fallen below 34° F., and says—
‘These conclusions are only links in the grand chain of
evidence obtained from the examination of the Miocene flora
of the whole of Europe. They prove to us that we could
not, by any re-arrangement of the relative positions of land
and water, produce for the northern hemisphere a climate
‘which would explain the phenomena in a satisfactory way.
We must admit that we are face to face with a problem
whose solution in all probability must be attempted, and
we doubt not, completed by the astronomer.”

Whilst there are many reasons, as I have shown in the
first part of this paper, for believing that the mean tem-
perature of England might be greatly reduced by geographical
changes, there is nothing whatever to lead us to conclude
that the present mean temperature of Spitzbergen could
be raised by any alteration of the relative positions of the
sea and the land. By the present arrangement a large body
of warm water is poured past that island, deflecting the iso-
thermal lines in a great tongue northwards, which embraces
it in its apex; and no conceivable geographical re-arrange-
ment could raise its mean temperature more above that due
to its latitude than what is effected at present.

No re-distribution of land and water could compensate
for the length of the Arctic night. Lyell has speculated
on the possibility of the trees living without light for months,
and thinks they might survive through the long darkness.

* Student’s Elements of Geology, p. 223.

1874.] Climate of the Glacial Period. 461

But long nights mean extreme cold: the one cannot occur
without the other. The earth rapidly radiates its surface-
heat into space, and, if the loss be not compensated for by
what is received from the sun, the temperature soon falls
far below the freezing-point.

Neither could any possible increase in the eccentricity of
the earth’s orbit alter materially the length of the Arctic
night; nor could the moderate amount of change allowed
by astronomers in the obliquity of the ecliptic. Taking
their highest limit, the Arctic night in lat. 78° 56’ would
still last for three months, during which the sun would
not rise above the horizon. It is impossible but that the
radiation from the earth during that time would produce
intense cold. This long night could be lessened in one
way, and one way only,—by a much greater change in
the obliquity of the ecliptic than astronomers have yet
admitted can have taken place.

In an enquiry of this kind it is well when we can get
down to such a crucial fa¢t as is that of the flourishing
of many species of large trees so far within the Arctic
Circle. It is of far more importance than any or all the
arguments I have used about the Glacial period. It admits
of but one explanation. The long Arctic nights are caused
by the obliquity of the ecliptic, and only by the lessening of
that obliquity can they be shortened. There is no reason
to believe that this vegetation could have been fitted to
endure extreme cold. It belongs to many different genera,
and the greater part are not these that are now characteristic
of cold regions. For these, according to Heer, we should
have to go to the very Pole itself. At thesame time, in North
Greenland, flourished a flora that could only live where frost
was unknown. Many of the same species lived much
further south along with subtropical forms that prove that
the climate of Central Europe was then both much warmer
and more equable than it now is, and Heer considers that
the mean temperature of North Greenland would have to be
raised at least 29° F. to enable the Early Tertiary flora to
flourish there.

I have shown that a great increase in the obliquity of the
ecliptic would produce the cold of the Glacial period, let us
now consider what would be the effect of a great decrease
in that obliquity. Would it tend to produce conditions
faveurable for the growth of vegetation up to the North
Pole? It will simplify the question by investigating how
far an entire obliteration of the obliquity would ameliorate
the climate of the Arctic regions. The present position of

Wor. IV. (N.S.) 3N

462 Climate of the Glacial Period. [October,

the axis of Jupiter proves that there is nothing impossible
in the supposition that that of the earth may also have
been perpendicular to the plane of its orbit. The immediate
effect would be the equalisation of night and day all over the
world. With twelve hours’ sunshine and twelve hours’
darkness the seasons would disappear, or rather every
parallel of latitude would have but one. At the equator
alone would the sun rise dire¢tly overhead at noon. In the
temperate zones would reign perpetual summer; within the
Arctic circle perpetual spring. In Central Europe sub-
tropical vegetation might then flourish. In North Green-
land the sun every day would rise to a height of 20° above
the horizon.

The forms of the continents were very much the same as
they are now. It is probable that the Gulf Stream exercised
the same sort of influence as it does at present on the climate
of the North Atlantic, and it is significant of that influence
that the most northern Early Tertiary forests have been
found in Spitzbergen, whose shores it now laves. The
flora of North Greenland suggests that a branch of the
Gulf Stream also flowed up along its western coast. With
twelve hours’ sunshine, ice could not accumulate in Baffin’s
Bay, and it is not improbable that some of the warm surface
currents of the ocean then found a passaget hrough Davis’s
Strait towards the Pole. Under such circumstances the
west coast of Greenland might have its mean temperature
raised as much as Prof. Heer thinks is necessary. During
the day twelve hours’ sunshine would give it the heat of a
mild summer’s day, and at night the warm currents flowing
past its shores would prevent the occurrence of frost. The
sequoia and the magnolia might then flourish and perfect
their fruits in North Greenland; and even at Spitzbergen
the Gulf Stream might cause frost to be unknown ; but there
the sun would rise to such a small altitude that the climate
would not be warm enough excepting for hardy northern
trees.

Whilst the cold of the Glacial period and the heat of the
Early Tertiary period might thus be caused by a great increase
or a great decrease respectively of the obliquity of the ecliptic,
the extreme point to which the ice reached southwards, as in
America, and that to which vegetation reached northwards,
as in Spitzbergen, were both due to geographical conditions
still in existence. In both periods we have evidence that the
isothermal lines were deflected far northwards by the Gulf
Stream, and that the east coast of America was much
colder than the west coast of Europe. The evidence is

1874.] Climate of the Glacial Period. 463

overwhelming that the primary causes of these great oscil-
lations of temperature were changes in the direction of the
earth’s axis; and, fortified by the conditions that we see
obtain in the other planets, we may ask astronomers to re-
consider the question of the possibility of these changes
having taken place. Additional data respe€ting the exact
figure of the earth have accumulated since the problem was
last treated. The irregular figure of the earth must affect
the result; and it is not probable that the effect of the
attraction of the sun and the planets upon an irregular
equatorial protuberance can cause a perfectly circular move-
ment of the poles. None of the other movements of the
heavenly bodies are circular, and why should this one be?
The weak point in Lieut.-Col. Drayson’s theory is the
assumption that the imaginary line that the pole of the
earth traces in the heavens is that of a circle. Through
removing the centre of that circle from the point first fixed
by other astronomers to another, he accounts for the cold
' of the Glacial period, but offers no explanation of the heat
of the Early Tertiary period. He has, however, informed
me that the curve really traced may be that of an ellipse or
of a spiral, the time over which accurate observations
have been made not being long enough to determine the
exact figure. Geology teaches us that the obliquity of the
ecliptic has been much greater and much less than it is
now, but with the cause of these changes it cannot deal.
This must be left to astronomy to decide, and I doubt not
that the solution of the question will be attempted, and,
notwithstanding its difficulty and intricacy, accomplished.

I have now come to the end of my argument. I have
had more than one object in view. Besides trying to make
plain what I considered the fundamental cause of the great
oscillations of temperature, of which we have such abundant
proofs in geology, I desired also to indicate the vast scope
of the enquiry that the study of the Glacial period involved.
It is not simply a question of scratched blocks and transported
boulders. The whole physical geography of the world has
been affected by it. Man’s early history and his present
distribution are intimately connected with it. Not only the
valleys and the fiords of the north, but the great plains of
Europe and Asia were produced by it. Even the existence
of our continents may be due to a succession of Glacial
periods that have from the earliest geological times dis-
turbed the equilibrium of the earth’s figure, and the volcanoes
and the earthquake shocks of the present day may be

464 Climate of the Glacial Period. (October,

occasioned by the slow recovery from the last disturbance
of that equilibrium. Viewed in these lights, the history of
the Glacial period has yet to be written; and whoever has
time and ability to take up the study will find it one of ex-
treme interest.

In treating the subject as I have done I know I must
with many have weakened my argument by introducing
questions not directly bearing on it. They will turn to
some text-book and find it stated that the greater part of
England was submerged 2000 feet below the sea in Glacial
times; or that the secular cooling of the earth is an in-
contestable physical necessity; or that in some other way
I have propounded a scientific heresy. ‘They will fail to see
that the main argument is not affected by these auxiliary
theories, and they will decide against me. The human mind
falls back on precedent and authority, and an original investi-
gator must expect that every step he takes will be disputed.
And in many ways the result is most beneficial, for the
theories that survive do so because they have an innate
vitality that carries them through all opposition; and those
that cannot stand the test soon succumb to the chilling
blasts of gusty criticism.

There are others, however, who will consider the argument
strengthened and not weakened by these subsidiary specula-
tions, for they know that it is characteristic of a true theory,
like that of gravitation or the undulatory theory of light,
that it explains numerous facts not originally contemplated
when it was first suggested. Many must have been led to
adopt the beautiful theory of the origin of species by natural
selection, through finding that it afforded welcome help in
the solution of problems in natural history besides those
that Darwin first sought to explain by it. And I claim for
this theory that it shows these signs of truthfulness. It not
only explains the grand facts of glaciation and of the
Arctic Tertiary flora, but it throws unexpected light on
such far removed and seemingly unconnected facts as the
traditions of a great deluge, the production of volcanic
eruptions, and the growth of coral islands. It is the
problem of human knowledge to bring the accumulating
facts of the world’s history through all time into one con-
sistent and harmonious chain of consequences, and I trust
I may in this paper have contributed towards that end. ©

1874.] ( 465 )

mi LOSS OF LIPE =Al SEA.
By Rear-Admiral FISHBOURNE.

HE loss of life and property on the high seas having
grown to such enormous proportions that it became
the duty of the Government to enquire whether much

of this did not arise from preventable causes, we were not
surprised therefore that a Royal Commission should have
been appointed, or that they should have presented us with
an instructive and highly valuable Report.*

Notwithstanding that, on the whole, the Commissioners
have arrived at wise conclusions, their Report bears the
marks of having been produced under pressure, the Com-
missioners working against time, and that some aspects of
the subject were new to them. We are glad to give promi-
nence to some of their recommendations, which we think
cannot be too strongly insisted on :—

That ‘“‘the Board of Trade should interfere only when
there is ground for suspecting some gross mismanagement,
and, whenever the case for detention may appear doubtful,
to direct the attention of the ship-owner or manager to the
circumstances which have attracted official notice.”

“That the Marine Department of the Board of Trade
should be revised and strengthened.”

Some additional nautical assistance ‘‘is requisite for the
due performance of the duties now entrusted to the Board.
A legal adviser exclusively belonging to the Department is
also essential.”

‘It will be the duty of the Board of Trade to check the
negligent and to punish the culpable ship-owner, but it is
desirable that these fun¢étions should be performed without
harassing the great body of ship-owners, who, by their
ability and indefatigable energy, have contributed to the
prosperity of the Empire.” And while they wisely deprecate
any transference of responsibility from the ship-owner to
the Executive Government, they add—‘“ It is the duty of
the ship-owner to keep his ship in a seaworthy condition,
and to select competent officers and crew.’

While the Commissioners insist upon the propriety of
ship-owners being exempt from vexatious and injurious in-
terference, they recommend that their natural and just
responsibilities should be enforced, and even made more

* Report of Royal Commission on Unseaworthy Ships.

466 Loss of Life at Sea. (October,

stringent: thus they say—They “think that in analogy to
the principle involved in the eleventh section of the Merchant
Shipping Act Amendment, 1871, the ship-owner’s liability
for damage to property or person should be unlimited in
cases where the death of the seaman or the damage to
person and property has been occasioned by the ship having
been sent to sea in an unseaworthy condition, unless he
proves that he—or those to whom he commits the manage-
ment of his business—used all reasonable means to make
and keep the vessel seaworthy. He should also, in these
cases, be made liable, under Lord Campbell’s Act, to the
family of the deceased seamen.” They ‘‘are also of
opinion that any provision in a bill of lading or other
agreement, having for its object or effect to avoid or limit
the liability of the ship-owner in the cases just referred to,
ought to have no legal validity.” They ‘think that the
ship-owner should not be enabled to recover his insurances,
whether under a time or voyage policy, when it could be
shown that he or his agent had not done everything
reasonably within their power to make and maintain the
ship in a seaworthy condition, and that unseaworthiness
occasioned the loss.”

Fixing such grave responsibility upon the ship-owner
makes it imperative on the Government to protect him
against that growing spirit of insubordination, carelessness,
and ignorance on the part of the crews. With this view
the Commissioners recommend enactments and prosecution
under them of captains, mates, or men, whose defaults have
occasioned the loss of life or property, and they properly
recommend—for the owner cannot be well made responsible
for acts committed abroad to which he is not privy—that
the eleventh section of the Merchant Shipping Act, 1871,
should be amended, and be made expressly to extend to the
master of the vessel; for it is very important to avoid any
doubt that the master who, without justifiable excuse, leaves
port with his vessel in an unseaworthy condition, renders
himself amenable to the criminal law.

The Commissioners justly attach great importance to in-
stituting, in every case of disaster, a searching and impartial
enquiry, to ascertain whether the casualty is owing to the
faulty construction of the vessel, to bad stowage, to circum-
stances connected with the navigation, to the incompetency
of officer, or to the neglect or misconduct of the crew.

No mere preventive or repressive measures can wholly
meet the real difficulty which largely arises from a low
moral standard amongst both seamen and officers, some of

mo74. | Loss of Life at Sea. 467

whom have worked their way up from the ranks, and have
not had equal advantages with others; therefore it is with
unmixed satisfaction that we view the approval given by the
Commissioners to the training ships, and the duty of the
Government to aid such; and we still further rejoice that
the present First Lord of the Admiralty has given official
recognition and approval to the view of the Governmental
obligation.

In some respe¢ts these training ships may not be thought
an equally good school for seamanship, but it is a far better
nursery for the growth of bone and muscle, and far more
for the formation of character, and for establishing moral
and religious principles,—the only sufficient guarantee for
good service and good citizenship,—while they receive an
education which in every particular is germane to the duties
they will have to perform when they are fairly embarked in

the duties of their profession.
- Once more, we rejoice that England is not content to
have the residuum of other nations to man her ships, and
still less content to play the stepmother with her own off-
spring, but undertakes to fit them by the tens of thousands
to fill fittingly noble duties opening the door to higher
destinies.

We do not know whether the Commissioners allude, in
their opening remarks, to the agitation originated—perhaps
not wisely, yet not without cause—by Mr. Plimsoll, when
they say—‘‘ Public attention has been eagerly dire¢ted to
some of the above precautions.”” Other sources of danger
have been altogether unnoticed. ‘‘ Adding a summary of
official enquiries into wrecks and casualties, excluding col-
lisions, shows that from the year 1856 to 1872 inclusive, a
period of seventeen years, while 60 ships were known to
have been lost from defects in the vessel or in the stowage,
711 ships were lost from neglect or bad navigation.”

In this the Commissioners are scarcely fair, for they
admit that these statistics are hardly reliable, and on page 4
they prove them to be utterly worthless, for there they prove
that during the first nine months of the operation of the
Merchant Shipping Act, 1873 (36, 37 Vict., c. 85), out of
286 ships surveyed, 256 were found to be unseaworthy,—
234 from defects in the ship or equipments, and only 22 from
being overladen.”’

This return shows how comparatively futile would have
been the special provisions intended by Mr. Plimsoll’s Act
for determining the load-line and limiting the deck loads to
summer seasons, while his recommendation for general

468 Loss of Life at Sea. (October,

inspection would have been intolerable ; and if this army of
Inspectors were not more capable than some of those now
employed, the results would have been most injurious to the
trade and dangerous to the sailor. If Mr. Plimsoll would
benefit the sailor and his country he must seek other support
than Mr. E. J. Reed’s exaggerated statements about vessels
being loaded till the water washed over their decks. Mr.
Reed joins Mr. Plimsoll in his attempts to prevent deck
loads being carried, because of raising the centre of gravity
of ships, which is the occasion of their capsizing, and this
top weight is further added to in the winter months by
the seas that then come over their bulwarks. It requires,
however, but a small acquaintance with every-day facts on
the Thames to have known that barges and yachts are to be
seen with the gunwhales immersed and inclining almost
with the water up to their masts, and without a shadow of
danger. So, also, the Dutch galliots, on the high seas,
allow the water to have free access to many parts of their
decks amidships, and this because they have wisely supplied
a sufficiency of the cardinal element of safety, viz., stability.

The Commissioners come to the conclusion that ‘‘ the
reserve of buoyancy,” which they define to be “‘ the propor-
tion which the capacity of the water-tight and solidly-
constructed part of the ship which is above water bears to
the capacity of the part immersed,” should ‘‘ mainly guide
in the settlement of.a load-line.” Further on they add—
“‘ Any rule of freeboard founded on surplus buoyancy gives
to a vessel of light scantling an advantage over a stronger
vessel. Thus the inferior ship would by law be allowed to
carry the heavier cargo. Such an enactment would not
contribute to the safety of life at sea.”

‘‘ There is no general agreement as to a rate by which the
requisite amount of reserve buoyancy could be determined,
and it appears that, except under definite circumstances,
it is not a determinable problem.”

“The proper load-line in each particular case depends
not only upon the principal dimensions of the ship, but also
upon her form and structural strength, the nature of her
cargo, the voyage, and the season of the year.” Again,
they say—‘ Discretion as to the proper loading of his ship
must be left to the ship-owner, or, under his dire¢tions, to
the manager, on whom the responsibility rests for sending
the ship to sea in a seaworthy condition, which responsibility
it is inexpedient to diminish. ‘They have therefore come to
the conclusion, not without regret, that we cannot prescribe

1874.] Loss of Life at Sea. 469

any universal rule for the safe loading of all merchant
ships.”

This is all true so far as it goes, but it is very unsatisfac-
tory that it goes no further. They omit from the list of
considerations that should influence the load-line, the ruling
one—that of the disposition of the cargo: this wrongly
stowed renders nugatory, as regards safety, all care that
may have been bestowed upon other points. Then there is
a looseness in the use of the term zeserve buoyancy that
ought not to occur; the mere fact that a part of the vessel,
as she floats, is above water, by no means proves that this
is reserve buoyancy—it may be absolutely without buoyancy,
and may be, so to speak, only waiting for an opportunity
to take its natural place below. The ship may have become,
by bad stowage, what Sir Edward Watkin styled—when
speaking of vessels designed by Mr. Reed—a “‘ ship upside
down.”

Buoyancy, to be efficacious in that degree, must be real.
Buoyancy is the hydrostatic pressure that supports any body
floating in a fluid. It is equal to the difference between the
mean specific gravity of the floating body and the fluid in
which it floats multiplied by the displacing volume.

It is clear, from the above exact definition, that unless
that portion of the body which is temporarily above water
is of less specific gravity than the water in which the body
floats, it does not possess buoyancy, and cannot give any
support.

We strongly object to the season of the year being taken
as a consideration when fixing the line to which a ship
should be loaded, as it implies that it is proper that a ship
should be less safe in summer than in winter, forgetting
that she may cross the Tropics, and thus pass from summer
into winter, and that she may, and they do, frequently meet
with abnormal seas and winds in summer; besides, ships
stowed on such erroneous principles as these cannot be
otherwise than proportionably unmanageable and ineffective,
and do not bring profit to the owners.

The Commissieners seem to recognise the faultiness of
their definition of buoyancy, or rather the erroneous ideas
that are current about it amongst those who inculcate that
it matters not where the buoyancy is placed, so only it be
sufficient in the aggregate; for they say (p. 6) :—‘‘ Double
bettoms for water-ballast are attended with danger, because
when the cargo is taken on board these spaces are emptied
of water, and this may tend to capsize the ship. There are
many cases where the double bottom affords additional

VOL. IV. (N.S) 30

470 Loss of Life at Sea. (October,

security ; any legislation on this matter would therefore be
inexpedient.”

We fear in too many cases the possible advantage of a
double bottom in very remote cases, such as taking the
ground, is made the justification of establishing a permanent
danger of capsizing, as alluded to by the Commissioners, but
further of effecting the danger it provides against, for the
existence of an inner bottom leads to scamping the work on
the outer, and reducing its strength far below that which it
ought to be.

This tendency to capsize was designed to be the normal
condition, as we learn, of many of our vessels of war, and
evidence has been given concerning some of them, that their
outer bottoms were too weak to bear their own weight when
grounded, and so they would not have taken a first-class, if
any, certificate at Lloyd’s.

We are glad to find the Commissioners recognising the
danger of light bottoms, and of ill-adjusted deck-loads, and
therefore inferentially condemning that system advocated by
Messrs. Froude, Reed, and others, of giving ship’s little
stability, not simply in the abstract, but actually contending
that little stability was a prime element in safety, than which
no system can be less well founded or more dangerous; but
we think the Commissioners ought to have gone further,
and, instead of saying that they “‘ could not give any universal
rule for the safe loading of merchant vessels,” should have
stated that the cardinal element in a ship’s safety and
effectiveness is in great stability, and for this their centres
of gravity, when loaded, should never be much above the
centre of their immersed body. ‘This would dispose of the
difficulties of low freeboard and water-line and deck-loads.

The Canadian authorities except deck-loads of deal on the
principle, reasonable enough, that they are light as compared
with the other part of the cargo. Deck-loads of cotton and
of deals even are dangerous when the general cargo is only
cotton and light wood, for in such vessels it is nearly im-
possible with such to get the centre of gravity low enough
for safety. Nor is there any danger of uneasiness in recom-
mending so low a centre of gravity in merchant ships, since
their proportion of breadth—which is the disturbing and
antagonistic element, so to speak, as respects motion—is
small, and the tendency is to making it smaller, for the sake
of greater cargo-carrying and small masts and small crews.

The Commissioners have properly recommended that
responsibility shall be shared out to all concerned in due
proportion—captain, mates, crew, and owner,—but, while

1874.] Loss of Life at Sea. 4727

insisting that the safety of a ship cannot be secured without
care and vigilance be given from her first design to her un-
loading at the port of destination, they fail to mete out to
the architects and builders, who uniformly claim the lion’s
share of success, any share of responsibility or blame for the
failure of designs: and yet most of the great catastrophes
lie at their doors, and many of the smalier are due to their
misleading, or to their, and that of other peoples’, assuming
that in dealing with purely nautical subjects they can
dispense with nautical experience and knowledge, and can
decide all nautical questions without the assistance of seamen.
We rejoice that the Commissioners are no parties to the
discrediting of nautical knowledge in naval questions.

As Mr. Froude’s theories concerning the best mode of
preventing the rolling of ships in a seaway have been ex-
tensively applied in our navy, it has become a matter of
great importance to demonstrate their erroneous character,
and to point out the great danger of continuing to apply
them.

Let us now examine the principles on which Mr. Froude
proceeds.

He alleges that “‘the effort of stability is the lever by
which a wave forces a ship into motion; if a ship were .
destitute of this stability,” he says, “‘no wave that the ocean
produces would serve to put her in motion.”

He offers the following explanation and illustration in.
proof of the correctness of the above view:—

‘*T regret you did not notice the conclusive experimental
proof I exhibited of the fundamental proposition, that the
surface of a fluid when dynamically inclined is virtually
level to a body which floats on it, and as it really lies at
the root of the whole theory of the behaviour of a ship
amongst waves, I am anxious that not only my re-statement
of it, but reference to the experimental proof of it, should
appear also.”

Mr. Froude then gives the following as the experimental
proof of his fundamental proposition.

‘** If a shallow dish of water be suspended by three equal
strings brought to one point, so that it is level when it hangs
at rest, then if the meeting of the strings be taken in the
fingers, the dish may be swung about in any direction what-
ever without spilling the water; indeed, it is impossible to
spill the water so long as the suspending lines are kept
tight by the operation; and if a stable floating body be
placed in the water it will carry its mast at right angles to

472 Loss of Life at Sea. (October,

the water, whether it owes its stability to deeply-stored
ballast, or to a broad plane of flotation.”

Now there are other conditions that must be complied
with before the floating body can be swung in “any direc-
tion whatever;” and it is not impossible to spill the water “‘so
long, merely, as the suspending lines are kept tight by the
operator,” for the water will inevitably be spilled if the
motion be not communicated concurrently, slowly, and
equably to the containing vessel and the water: moreover,
when the model ship is placed on the mimic sea, it also must
be so placed before motion is communicated to the dish and
water ; for if all are not put in motion at the same time then
the motion of the ship and water will not synchronise, for
they will be subject to different amounts of force, and ‘‘ the
fundamental proposition ”’ will be seen not to hold good.

The principles contained in the experiment are the same
as those which obtain in the milkmaid’s trick of swinging her
pail of milk over head, and in the practice of the sailor in
swinging his sounding lead over his head: in each case
sufficient velocity in rotation must be given to overcome the
gravitating force, or the milk will be spilled, or the sailor
will be advised of his stupidity by a good thump. In the
case before us, unhappily, it is the sailor who is punished,
because another, the philosopher, ignores the existence of a
well-known law.

Mr. Froude, having stated his fundamental proposition
that ‘“‘the surface of a fluid when dynamically inclined is
virtually level to a body which floats on it, overlooks the
essential difference between the conditions which obtain in
his illustration and those which obtain in a ship in a seaway.”

Because the floating body on his mimic sea is subject to
the like dynamic forces with the water, and moves with it,
he assumes that a ship in a seaway “‘is subjected to the
same dynamic force as the wave on which she floats, and
might be treated as a surface particle on it,” which is simply
impossible, as a ship is subject to other forces than those
which the sea give out; and though she is subject to the
motions of the wave, she does not accept the wave motion,
for if she did, her motions would always synchronise with
those of the wave, which they never can entirely do.

And notwithstanding that the floating body on his mimic ~
sea would continue to move with the water (if once set in
motion with the water, and is not subject to any other force, —
as a ship amongst waves is), whether the form of body
were V- or U-shaped, whether the centre of gravity were

1874.] Loss of Life at Sea. 473

high or low, whether the body had one keel or a dozen,
small or large ; and this, because there is no motion of the
particles of water amongst themselves, nor of the floating
body amongst them, other than those produced by the one
power ; they all being moved by the same power at the same
time, and to the due extent, according to their relative
positions in the orbit of motion, the upper parts or particles
moving in the least arcs, though their motions may be
modified by the law of gravitation; yet every one of the
above changes in form, in weight, and in disposition of the
weights, would affect the motions of a ship in a seaway in
facilitating or in retarding motion, so that a ship’s motions
could not synchronise with those of the wave. Moreover,
as the motions of the water in his illustration are different
from those of water in wave motion, in which the upper
parts or particles moving with greater velocity than the
lower, there is no analogy to the conditions of the water in
the dish ; also as the parts of a ship are substantially rigid,
and one part occupying space amongst the fast-moving
particles, and another part amongst the slow-moving
particles, it is impossible that the ship could move wholly
with either one set or the other, or with both more than in
part, and in some varying degree. Again, while in his
illustration the containing vessel, the sea, the floating body,
and all the water are moving together under the impulse of
the centrifugal force; in the case of a ship at sea there is a
portion of every ship that is down amongst the unagitated
water, below wave motion; this portion of the body would
resist and retard motion, and prevent a ship from accepting
and moving. with the waves, if otherwise free or disposed
to retain her masts perpendicular, to the slope of the wave.
Indeed, were it true we should not have any such cases as
ships and boats being rolled over by waves, which are only
too numerous, and will be more so in proportion as his ideas
on that subject are adopted.

In fact in no case are the circumstances of a ship amongst
waves similar to those of the illustrative model, nor can a
ship ever ‘“‘ accept the aggregate dynamic conditions of the
sea on which she floats,” nor still less ‘‘be treated” with
any regard to truth ‘‘ as a surface particle of the wave on
which she floats.”

There are also further limitations on the motions of a
ship in a seaway, to which the model in Mr. Froude’s
illustration is not subject.

Thus the amount of a ship’s motions are the result of the
wind on the sails, or on the hull and masts, or the inertia

474 Loss of Life at Sea. (O&tober,

of the masts and sides of the hull, together with the ever-
varying resistances from onward, and from rotatory motion ;
while in the case of the model there is but one motor, and
one influence ruling, that and gravity being common to both.

Nor can it be conceived with any approach to correctness
that the place of the operator’s hand, as specified in* Mr.
Froude’s illustration, ‘‘ holding ever so tightly the strings,”
can represent the pommt of buoyant suspension of a ship, or
even on the principle that her motions are analogous, as
they are not, to those of a conical or other pendulum, nor
that the three strings represent the lines of buoyant power
meeting in the hand of the operator.

These forces, as the ship rolls or is inclined, are con-
tinually changing in direction and in amount, as it were,
first on one string then on the other; therefore the point of
suspension and length of strings are continually changing.

Lastly and conclusively, the conditions of Mr. Froude’s
illustration require that the ship shall be suspended by three
or more strings or something analogous; and not that only,
but that the wave or waves on which she partially and tem-
porarily floats shall also be like as in the tray experiment sus-
pended; not that alone, but that each wave as it arrives up
to and passes under her shall be likewise so suspended; nor
that only, but that the ship, the sea, even to the depth to which
any portion of the ship is immersed, and a portion of which is
always below the limit of the depth of wave motion, and all
altogether shall be supported on three or more strings, and
be all moved together and to the same extent by an invisible
hand communicating motion from one point above the ship;
whereas everyone must know, if he knows anything about
the motions of ships at sea produced by waves alone, that
instead of this imaginary hand or power moving the ship
from above, the ship is always in a seaway moved from below
without the intervention of strings, and that the water and
not strings or a hand or anything analogous is the motor,
and which, unlike the hand and strings in the experiment,
never succeeds in wholly imparting its own motion to the
vessel floating on it.

There is nothing of that which is required by Mr. Froude’s
theory, which is therefore a mere fiction; and though there
doubtless is a superstructure of superior mathematics built
up by him, yet as it is baseless, his conclusions could not be
otherwise than erroneous and proportionably deceptive, and
the adoption of them could only lead to the damage of our
ships and danger to the lives, if not also to the death, of
some of our seamen; and so it has proved in the sad fate

1874. | Loss of Life at Sea. 475

of the loss of the Captain, and in the great danger to which
other ships were exposed, as the writings of the advocates
of these erroneous views have practically admitted.

Then he says, “‘ The effect of stability is the lever by
which a wave forces a ship into motion. Ifa ship were
destitute of this stability no wave that the ocean produces
would serve to put her in motion, whether the stability be
due to deeply-stored ballast or to the broad plane of flotation.”

Yet the effort of stability is originated by, and is not the
originator of, motion; it is the effort put forth in resisting
motion, and increases in amount with each increase of the
extent of the motion up to a certain point.

Stability may be obtained either by deeply-stored ballast,
or by a broad plane of flotation, or in part by both; but they
are unlike, and in some degree opposite in their operation
and effects; yet here also Mr. Froude treats them as though
they were strictly alike in their operation and in their
effects.

No doubt the plane of flotation in proportion as it is wide
when the sea is motionless, therefore not a motor, gives a
very high degree of stability ; but when the water is moved
into waves, that same broad plane becomes proportionally
an instrument but not a motor, by which the waves give
much greater motion to the ship, they being the power that
puts the ship in motion—making her unsteady yet not un-
stable, as is argued by Mr. Froude, for in that case she would
capsize, as his model also would if unstable, and would not
preserve its masts perpendicular to the surface of the water,
this new hypothesis notwithstanding.

Unquestionably if a ship be without stability, as Mr.
Froude suggests, she will be unstable and not steady, but
will do the opposite to that stated by that gentleman, viz.,
“not be rolled by any sea whatever,” for she will certainly
roll over, as was near being demonstrated in the case of the
Vanguard and her sister ships; no doubt she will not roll in
the sense of rolling from side to side, for being once rolled,
and not possessing stability to bring her back to the per-
pendicular even when the rolling force ceases to act, she
will roll over.

Still less is there any tendency in ballast or a low centre
of gravity ‘‘ to put a ship in motion ;” its action is to pre-
serve the motionless condition of the ship, and it possesses
no leverage till by motion it has been pushed out of the
perpendicular by some force which is neither that of stability
nor of ballast, ballast itself never being even like the broad
plane of flotation, an instrument in originating greater

476 Loss of Life at Sea. |October,

motion; on the contrary, when it is pushed out of the per-
pendicular, its effort is always to bring the ship back to the
motionless condition, and its effort in this dire¢tion is greater
in proportion to the extent of the disturbance from the per-
pendicular, a disturbance originated by that other force;
and in proportion as the ballast or centre of gravity is lower
does it tend to limit the extent of the motion, which is the
opposite of the action of a broad plane of flotation.

In proportion as the stability is derived from the weights
being placed low, and relatively great as compared with the
smallness of the plane of flotation, a ship will roll less and
less.

Many have seen this fully illustrated in the steadiness or
freedom from rolling with which a boathook floats in the
midst of waves.

This condition is also well illustrated by a floating target,
which remains vertical because of its studiously low-placed
centre of gravity and small plane of flotation.

Let anyone take a boathook and load it still further near
the hook so as to push it well down into the water, and
arrange that the stave or wood handle shall be as small as
will consist with floating the added weight if placed in the
midst of high waves, it will be found to float, and continue
to do so nearly upright, the waves as they pass running up
the stave without inclining it further or rolling it, and why ?

Because the great weight acting low down with all the
force of the stability which it gives out, in consequence
even of the small incline from the perpendicular, is exercised,
not as Mr. Froude suggests, ‘‘to put the ship or handle in
motion,” but to prevent further motion except in the vertical
plane; and the ballast succeeds in preventing motion,
because the whole plane of flotation, or more properly the
volume subject to immersion and emersion as the waves and _
hollows between the waves pass, and which alone constitutes
the instrument through which the waves act to put the ship
in motion, is little or nothing compared to the force of the
low weight, and to the action of the body low down in the
undisturbed water, resisting motion. The obvious course
therefore to be pursued, when it is desired to reduce the
amount and the rapidity of motion in ships, would be to
keep the plane of flotation comparatively small, the centre
of gravity low, and make the depth half the breadth or as »
great as would consist with general good qualities, and the
object for which any particular ship might be destined.

Instead of which two other courses are recommended by
Mr. Froude and his school, viz., to raise the centre of gravity

1874.) Loss of Life at Sea. 477

as compared with that in ships generally, and to distribute
the weight outwards and on to the sides.

We may examine the effect of such recommendations with
advantage.

The condition of ships in a seaway is misunderstood, as
is the effect of increasing the inertia of their sides ; the con-
dition is not as supposed by Mr. Froude, that of a ship
moving with and as a particle in the wave; when waves are
large or are steep, and are travelling fast across a ship’s
path, she has no time and may have very little tendency to
accommodate her seat in the water to the surface or level
of the wave, so that it becumes oblique to the ship’s water-
line, as in Fig. 1, producing an inequality in the pressures,
which are the cause of the rolling motions. All the con-
ditions of the pressures on the inclined body in still water,
shown in pages 73—4 of “Our Ironclads and Merchant
Ships,” holds good equally as to the upright body with
reference to an inclined surface of the wave.

In comparing two ships, or the same under different con-
ditions, we must assume the wave to be alike in all par-
ticulars, then consider the variables and their consequences.

The disturbing wave force then is the same, whatever
may be the form or distribution of weight in the ship; yet
the effect of that force will vary considerably as the above
are changed.

We will suppose Fig. r to represent the cross section of
a ship, which, by weighting her sides, is prevented from in-
clining with the wave, or from accommodating herself as
much as she otherwise would to the surface of the wave,
which is represented by the wave line curve.

There is a complete change in the amount of the pressures
from those that existed when the sea was level and the ship
upright ; suppose the new pressures to be represented by the
arrows at P Pp’, and #.

The water has accumulated at P, raising the point and
increasing the amount of lateral pressure on that side, while

VOL. Iv. (N.S.) 2 P

478 Loss of Life at Sea. (October,

the water has partially left the other side, decreasing the
pressure there and lowering the puint to £. These two
pressures act as a couple to rotate the ship; that at p high
up, and more high as the wave is higher and its upper par-
ticles moving with greater velocity. That at ps low and more
low as the hollow of the wave is deeper, and their power to
rotate the ship increases in the same extent.

Then Pp’, moved over to the side of greater pressure, acts
up on a line normal to the earth and perpendicular to the
mean level of the sea through ¢; G in the first instance
representing the position of the centre of gravity, and G¢ the
perpendicular distance from the line of pressure; this also
tends to turn the ship in the same direction as the other
pressures.

It is clear that the greater is the accumulation of water
the further p’ will be carried over, and the greater will be
the lever Gt, which in this case tends to overset; con-
sequently, any arrangements that would tend to increase
this accumulation of water would be injurious, and might be
dangerous.

Now suppose the centre of gravity lowered to a’,, then
the upsetting lever will be G’#’, which is obviously shorter
than Gt; consequently, lowering the centre of gravity
reduces the power of the wave to incline or roll the ship, and
tends to limit the arcs rolled through.

Or suppose, though it is less accurate, these three forces
to be represented by one at P passing up through the
centre of figure c’. In Fig. 2, it is clear that the greater
is the accumulation, the greater distance c’ will be moved
out from a line passing through the middle of se¢tion or
ship; therefore the greater will be the distances of a per-
pendicular to the earth passing through c’ from the centres
of gravity at G or at G’: obviously, as in the former case,
in proportion as the centre of gravity G is lowered, so the
disturbing lever is decreased.

It is clear also that the greater is the breadth, the greater
distance will c’ be carried out, and the greater will be the
disturbing lever.

The greater is the accumulation of water also, the further
is c’ carried out, and the greater is the disturbing lever.
The greater is the effect of Mr. Froude’s recommendations,
the greater becomes the upsetting lever.

The higher also the centre of gravity is, the longer is the
disturbing lever, and the greater is the extent of the motions
and danger of upsetting. (See p. 490 for a more definite
proof.)

1874.] Loss of Life at Sea. 479

The more rapidly the wave is moving, the greater is the
difference between the motions of the upper and lower
particles ; therefore the higher up is the lateral thrust, and
the danger greater from a high centre of gravity.

It may be said that, in lowering the centre of gravity, the
point round which the ship turns will be changed, and
therefore c’ will not occupy the same place under the altered
conditions. ‘This is true, but the fact is in favour of our
argument, for, in proportion as the centre of gravity is low,
the radius will be shorter, c’ therefore will be moved out a
less distance, and the injurious influence of the wave motion
will be proportionably less.

To assume, therefore, that the metacentric height is a
measure of the disturbing force is erroneous.

It is indispensable for a ship’s safety, as it also is for her
complete efficiency, that she should possess a considerable
metacentric height ; then to reduce this by raising the centre
of gravity, under an impression that the arcs of roll will be
reduced, is erroneous and an unmixed evil.

It ts not true, as stated by Mr. Froude, that ‘‘the effort of
stability is the lever by which a wave forces a ship into
motion. Ifa ship were destitute of this stability, no wave
that the ocean produces would serve to put her in motion,
whether the stability be due to deeply stored ballast or to a
broad plane of flotation.”

If, however, the metacentric height is made unduly high
by great proportionate breadth, or by placing a cargo of
metal on the ship’s floor, then the motions will be too rapid,
though short, in which case the evil may be got rid of, with
benefit and without danger, by raising the centre of gravity.
But still there is a minimum of metacentric height, below
which it cannot be reduced with safety.

Ships must yield to the waves, and all arrangements and
designs should be to facilitate their doing so slowly and
equably. The effect of Mr. Froude’s plan is to put off the
inclination till the wave accumulates in such force that it will
sweep the decks, force the ship over suddenly, and possibly
overturn her, if she be not previously “‘swamped.”

Therefore the metacentric height, or the distance of the
centre of gravity from the metacentre, must not be taken as
giving the measure of the disturbing force, for in lowering
the centre of gravity the metacentric height is increased,
but we have seen that in proportion as the centre of
gravity is lowered so the disturbing action and extent
of motion is limited; and therefore the proposition to
raise the centre of gravity, with a view to reduce a ship’s

480 Loss of Life at Sea. (October,

motions, is erroneous, and in proportion as it is raised it is
dangerous.

No doubt the other proposition, that of increasing the
moments of inertia by distributing the weights laterally, if
it gives the wave, so to speak, more to do to lift this weight,
on the one side, it must be remembered that there is, besides,
an accumulation of water on that side which overcomes these
moments; but there is a withdrawal of water support from
the other side, and that side tends to fall in search of
support, and, the more the weights are extended out on that
side, the greater is the force from that cause to rotate the
ship.

Obviously, their lateral distribution of weight increases and
renders a ship’s motions in a sea-way dangerous in propor-
tion as the waves are larger and more steep, the cure for
which is concentration of weight laterally and distribution
of weight downwards.

This has been immemorially the wise practice in bad
weather, to send small yards and masts on deck, to fill empty
tanks, and get the guns well in from the sides, and notoriously
the ships rolled less and were easier, and yet the stability
was increased by two causes, viz., lowering the centre of
gravity, and increasing the surface stability by reducing the
weight of the sides, increasing their buoyant power. Con-
sequently, the only distribution of weight that is safe in bad
weather is that which is downwards, and therefore raising
weights off the bottom, and concentrating them vertically, is
wrong on their own principle, as that reduces the inertia,
and doubly wrong on the principle we contend for, viz., the
propriety of lowering the centre of gravity and distributing
the weights vertically.

The proposition to get rid of the difficulties arising out of
the adoption of a wrong principle by increasing the breadth
and endeavouring to limit the motions this will entail, by
deep keels, will be a failure—

First, it will not effect the object intended. We have
passed the limit of practicable depth for useful ships, and
any increase of breadth will increase the disparity between
depth and half breadth, and occasion, as the ship rolls over
and rolls back, a greater rise and fall of the centre of gravity,
this action will occasion, so to speak, rolls, independent of
those produced dire¢tly by the wave by which the total are
of roll will be increased, together with an increase of rapidity
of roll, which keels cannot prevent if they will mitigate.

This rise and fall it was that caused the frightful rolling
of Sir William Symond’s ships.

1874.] Loss of Life at Sea. . 481

What will happen in a ship with weight concentrated on
her sides, high centre, and low freeboard, say on the
L’Aghulas’s bank, with a weather current and steep waves,
will be that the great inertia of her sides will resist their
rising to the wave, but finally it will lift her suddenly, but
a large body of water will break on board, and will rush over
to the other side. She will then have three forces tending
to turn her, the beam sea lifting the upper side, the weight
of water weighing down the lower side, and the current
running to windward below, making an adverse couple to
roll her over, all which will be facilitated by the empty cells
in her bottom. If she is not rolled over, it will be that a
good Providence has intervened; if she does capsize, we
shall know who to hang.

The same danger will arise from a weather tide or current,
and from great tidal and solitary waves.

There are two other elements that materially affect the
rolling motion, viz., length and depth: the greater these are
the greater is the resistance to rotatory motion. Then, in
proportion to the height of the waves, the depth of agitated
water increases, and so does the portion of the ship down in
unagitated water decrease, and with it the limitation to great
motion decreases.

It is universally admitted that the lower the centre of
gravity is, when once the ship is inclined by a force, the
more rapidly wiil this low centre bring the ship back to
the perpendicular, but then, also, in contradiction to
Mr. Froude’s view, must its power, of necessity, be greater
to resist the force of the waves, acting through the solids of
immersion and emersion to rotate the ship: also, the wider
the plane of flotation, the greater will be the leverage and
power of the sea to put a ship into greater motion ; and,
ceteris paribus, the higher the centre of gravity, the less
will be the leverage and power of the ballast, or low
centre of gravity, to resist motion. Therefore it is that in
proportion as the centre of gravity is high, and the vessel
broad, the effect of the sea in rolling the ship both rapidly
and through large arcs is greater! But obviously it is not
desirable that a ship should roll through large arcs, for in
that case the armour to be a real protection must cover the
whole side thus exposed from time to time at each roll, while,
in addition, to a greater degree, would the unarmoured deck
be presented to the enemy, and the employment of guns on
such a deck would be made proportionably difficult ; still
less is it desirable that these large arcs should be performed
rapidly. Therefore the plane of flotation should not be

482 Loss of Life at Sea. [Oétober,

greater than is necessary to give the requisite stability
without having the centre of gravity too low.

The correctness of the above reasoning was abundantly
shown in the behaviour of the ships forming the Channel
Squadron in 1871, the large ironclads exhibiting to great
disadvantage when compared with the small wooden and
unarmoured ships, though it is proverbial that, ceteris paribus,
the larger the ship, the better the weather she ought to
make.

Some of the ironclads rolled as much as 62°, some 56,
others 50°, while the much smaller Topaze rolled but 22°.

Again, while the little Topaze rolled but 22°, the large and
most approved ironclad Minotaur rolled 39°, and the large
and fine Northumberland rolled 38° under similar circum-
stances.

True, Mr. Reed attributes this difference to the existence
of that which he thus admits, though he had previously
denied it in former examples, the fact that the Topaze had
larger masts and yards for her size than the others.

But we may ask if large masts produce such remarkably
favourable and, we may add, essential qualities, why not
increase the size of the masts of the Minotaur, as they would
serve other useful purposes in addition? and why have
shortened the masts in the Vanguard class ?

The fact is that the effect of the difference of the size of
the masts in mitigating the rolling motions of the Topaze
was little compared to the disturbing effect of her broad
plane of flotation, and but for which she would be easier in
fine weather also, as she is so much easier in rough weather
than the ironclads. The proportion of breadth to length in
the Topaze was 1 to 4°7, while in the Minotaur it was I to 6°7;
the proportion of breadth to length of the Lord Clyde, which
was the vessel that rolled through the largest arcs, was also
Ito 4°7. In fact, the metacentric height of the Topaze was
greater than that of most of the ships present on that
occasion.

The rolling of these ironclads is without parallel amongst
wooden vessels, and is only approached by those of the,very
worst form, and yet the ironclads are, in some respects, of a
better form than the wooden ships; the excessive rolling,
taking them as a whole, being mainly, though not entirely,
due to the concentration of weight on the sides and want
of stability, the fact being that no ironclad possesses near
the amount of stability assigned by the ordinary mode of
calculating. This arises from the excessive overloading of the
solids of immersion and emersion, by the armour and by the

——

1874.) Loss of Life at Sea. 483

other concentration of weight toward the sides, the con-
sequence of which is that these portions of the ship are
deprived of buoyancy, and they afford the ship little or no
support ; so when she is inclined they tend little or nothing,
compared to their volume, to move the centre of buoyancy
over to one side or the other, in rolling,—so for want of this
support, amongst others, the ship rolls through large arcs,
once the sea has overcome the inertia of the sides.

And this evil would increase in each, as they were
lightened by the consumption of their coals, provisions,
and water, and their stability thus reduced. Great as
were the arcs of roll recorded of these ships, the probability
is that, with the exception of the Lord Clyde or another, very
little of their weights were out; so they were in the best
condition !—how bad the best !

The loss of the steamship Tacna is an instructive comment
on the foregoing arguments, and a complete condemnation
of the latest of the unsafe theories, 7.¢., that ‘‘ a vessel whose
stability is greatest when placed bottom upwards may yet be
perfectly safe when floating upright.”

The description of the loss, founded on a “‘ mature con-
sideration,” as given by the Court, is ‘‘the loss of the ship
Tacna was due to an excessive loading of her main and
hurricane decks, which, with the combination of circum-
stances adduced in evidence as having arisen at the time of
altering course for the port of Los Vilos, caused her to heel
over until, falling on her beam-ends, she filled and foun-
dered.”

The Court condemned the Captain for “‘ not having made
known in a more especial manner to his employers the
crankness of his vessel, and for not having exercised sufficient
care in the amount of deck cargo.”

Here is a ship “ floating upright” till she comes to turn,
when the centrifugal force, which is always greater as the
centre of gravity is higher, capsized her. But will any
reasonable man say she was safe ?

Even a Pacific sea or a squall would have done equally
what the centrifugal force did.

We have no question here as to a deficiency in the reserve
of stability which a high side is said to give. If we ask,
Where was her veserve of stability that she so went over ?
echo answers, Where ?

The captain was justly condemned for loading the ship as
he did, knowing her to be crank; but he was not responsible
for the latter, and he might in some degree be excused when
persons who are said to be the greatest authorities on such

484 Loss of Life at Sea. (October,

subjects say that crankness is a benefit and not a defect, so
they have recommended little stability !

The ship was lost, like the Captain, because ‘‘ she was not
endowed with sufficient initial stability ;”’ for this the naval
architect was primarily to blame, and merited condemnation
by the Court as having contributed to the loss of life which
occurred. Had the ship been lost within Chilian jurisdiction,
it appears the captain also would have lost his life.

The ship never was seaworthy from deficiency in her
initial stability, and whether that proceeded from direct
design, from a double bottom, and from not making due
allowance for that, or from an error in calculation, the naval
architect alone was to blame and ought to be held responsible;
and it will be useless legislating for the safety of lifeand property
if naval architects are allowed to do as seems good in their
own eyes without being held accountable. To say that the
deck load capsized this vessel is no exoneration, as the Froude-
Reed system provides that ships in a seaway shall have a
deck load of the greatest, most generally damaging and
dangerous kind, that of water, which will rush to the lower
side and guarantee an upset; for in providing so far as they
could that a ship shall remain upright in a sea, they provide
that the waves shall roll into and over her.

These gentlemen may say, Oh, no, we think there ought
to be sufficient stability to enable ships to carry the amount
of sail with which they are furnished. Let us consider
this :-—

The maximum pressure of wind must be assumed, acting
at the given leverage occasioned by height and area of sail;
in fact, the stability must be equal to the force shown by the
wind couple in the case; and more, as a force coming
suddenly is said to occasion double the inclination, the
stability should be double this; then the stability should be
sufficient to bear the ship up against inevitable deck loads
of water, or a blow of a heavy sea striking her when she is
inclining, such as proved fatal to the Captain, because of
her small initial stability.

The metacentric height, while that is the accepted mode
of estimating stability, ought not to be less than 6 feet for
smaller, and 5 feet for larger sailing vessels, somewhat less
for steam vessels with little more than fore and aft sail.

{t is clear no such quantity was contemplated for the
Invincible or Sultan anda fleet of other men of war, which
a deck load of water from a sea or other weight would have
cut short in their career while hardly begun if they had not
been heavily ballasted; and yet a vessel of war shorn of the

1874. | Loss of Life at Sea. 485

power to carry deck loads would often be useless; thus on
an 800-ton steamer it depended to keep up communications
with the army in Kaffraria and the colony, to throw in rein-
forcements, provisions, horses,and munitions of war, carrying
sometimes as many as 8o0 levies with their stores and pro-
visions, and this allon deck. Yet this vessel was proverbially
an easy vessel. Numberless instances of the necessity for
such a property could be given.

It may be affirmed also with confidence that various
exigencies occur when such a power is necessary in merchant
ships, such as taking crews off sinking vessels, and yet no
such power was provided for in the many ships that have
capsized because of their having deck loads.

It may be said that we object 77 toto to double bottoms,
though they are necessary, because the thin iron skin is
more easily perforated than is the wood planking of wood
ships.

We do not object to any proper use of a second or inner
bottom, to make iron ships stronger and safer against
injuries from taking the ground or from torpedoes, or to
facilitate repairs : such ships require it, as their bottoms are
far less strong and less calculated to bear injury than those
of wood ships; and we doubt not those iron vessels, with
deep iron bilge-keels, will be specially liable to damage ; nay,
more, that these very keels on taking the ground in many
cases will serve to tear a large portion of the lower bottom
out, if they do not injure the inner or upper bottom through
the frames, thanks to the little-stability system smuggled
into the navy to ‘‘ check rolling.”

We do, however, object to raising these inner bottoms
unduly for the purpose of raising the centre of gravity from
an idea that it is wise to do so.

We object to making the bottoms of vessels light, on the
grounds of cheeseparing parsimony, and then assuming that
this makes no difference in the properties of the vessel, that
the bottoms are equally heavy, though empty, with all
other parts of the immersed body, even when they are
crammed full, and then assuming that the results of calcula-
tions made on such an hypothesis can be otherwise than
erroneous, deceptive, and proportionably dangerous. ‘That
they are so we have proved in pages 34 to 44 of ‘‘ Our
Tronclads and Merchant Vessels,’”’* and need not repeat it
mere.

We have also demonstrated that in proportion as the spaces

* Our Ironclads and Merchant Vessels, by the Author. Harrison and Sons.
VOL. IV. (N.S.) 3Q

486 Loss of Life at Sea. (October,

between the bottoms are large and empty it will be necessary
for safety to lower the centre of gravity ; it will be necessary,
also, with the same object, to lower the centre of gravity in
proportion as the sides are more and more loaded and
deprived of buoyant power.

The oscillations of wide vessels with heavily weighted
sides are liable to carry them beyond the upsetting angle;
for this reason, also, their centres of gravity would require
to be kept lower.

It will beasked, What! was there nothing in past experience
to justify the adoption of the Froude-Reed system? No
facts, no experiments proving its correctness and safety?
absolutely none.

The one complaint in which all were for long agreed was,
that our ships were deficient in stability, from which they
always suffered in comparison with French and Spanish
ships. This led to the introduétion of Sir William Symond’s
system, and the success of his ships was entirely due to their
greater stability, which they maintained till greater stability
was given by his opponents.

His system was exploded because his stability was, for the
most part, obtained by a broad plane of flotation; therefore
his ships were more at the mercy of the waves, and their
motions were extravagantly extensive; the more so that
they were without a low centre of gravity to limit the range
of motion.

When steam was introduced the engines and boilers took
the place of ballast in keeping the centre of gravity low,
more necessary because of the reduced breadth to obtain
speed economically, and necessary because of the great
reduction of stability when the latter part of the coals were
being consumed.

A lower centre of gravity is necessitated in merchant
vessels by the fact that many of them are obliged to carry
deck loads.

As great stability and much of it bya low centre of gravity
was adopted as indispensable by common consent alike of
sailors and naval architects, the result of long extensive
and conclusive experiments, and represented by a metacentric
height of 5 to 6 feet or more, an architect giving much less
to a design would have been justly esteemed as foolish or
criminally ignorant. The laws of nature being unchanged,
how can it be otherwise now in giving metacentric heights,
such as 2°6 feet, 2°3 feet, 2°2 feet, and even 1°5 feet under
other much more unfavourable conditions? There was
nothing in the facts offered in justification of the course
pursued.

1874.| Loss of Life at Sea. 487

As we now propose to show:—Mr. Reed wrote, ‘the
steadiness at sea of our ironclads is due to their want of
stiffness or stability;” also that it had been found that
raising the centre of gravity tended to ‘‘check rolling, and
that it was a popular fallacy to suppose the armour-made
ships roll.”

It was recommended by Mr. Froude with a view to reduce
the tendency to roll to raise the centre of gravity of ships,
and to distribute their weights towards their sides.

Sir Spencer Robinson accepted the principle involved in
these statements and writes :—‘‘ It is remarkable, that ac-
cording to theory, the rolling of the ships being very much
influenced by the position of the centre of gravity with regard
to the metacentre, and by the moment of stability, the order
of rolling of the French ships as observed follows that law.”

The heat of the metacentre above the centre of gravity in
these ships is as follows :—

Armoured Solferino, 4°5 ft. Armoured Couronne, 5°37 ft.
Unarmoured Napoleon, 4’9 ,, ty Invincible, 6°36 ,,
Armoured Magenta, 5:0 ,, ve Normandie, 6°59 5,
Unarmoured Tourville, 5°31 ft.

‘*This,” he says, is “‘ precisely the order of merit they have
taken as to rolling.” The Solferino rolling least and the
Normandie the most.

Now we unhesitatingly affirm that there is nothing to
justify the conclusion that these gentlemen have come to,
viz., that the greater rolling was caused by the greater
metacentric height, but the reverse.

We accept the statement as to the performances of these
ships as given by Sir S. Robinson.

Ist. He says ‘‘that the Solferino is superior to all the ships
of both squadrons,” but this includes the Achzlles, yet her
metacentric height is only 31 feet, while that of the Solferino
is 4°5 feet; therefore the theory breaks down; nor is this
all, for the Solferino is nearly one-third smaller, 7.¢., of
2600 tons less displacement, than Achilles, and, therefore,
might reasonably be expected to roll more instead of less;
and while they have the same extreme breadth, which is the
disturbing dimension, the Achilles is go feet longer !

The decided superiority of Solfeyino must be due to the
lower centre of gravity and greater metacentric height, and
the weights being on her bottom tending to limit the arcs
rolled through or to “ check rolling.”

Again he states ‘‘that Achilles is quite as good as the
Napoleon ;” what! not much better? Why the metacentric

488 Loss of Life at Sea. (October,

height of Napoleon is 4°9 feet, that of the Achilles only
3°1 feet! The disturbing force of Napoleon may be repre-
sented by the cube of 55, that of the Achilles by the cube of
58; but then the latter is 147 feet longer and has only
4400 tons greater displacement! Moreover, the French
ship not being an ironclad did not possess the alleged soporific
of weighted sides. The theory here is doubly in fault. The
true explanation is a lowcentre of gravity, great metacentric
height, and weights on the floor.

Then the Achilles is said to be rather superior to the
Magenta, when she ought to be very superior, being so much
larger, that is, go feet longer and 2600 tons more displace-
ment, with same breadth of beam, 7.e., an equal disturbing
element. Here, also, the theory fails, and the explanation
is a lower centre of gravity and weights on the floor !.

Also, Achilles is stated to be decidedly superior to the rest
of the French squadron, excepting the Tourville. Why, the
metacentric height of this ship is 5°3 feet, that of Achilles
3°1 feet ; she is without the soporific of armour, is 140 feet
shorter and 4000 tons less displacement than Achilles. Again
the theory is doubly wrong.

Achilles is superior to the rest of the French squadron, 1.e.,
to the Couronne, the Invincible, and the Normandie. Really
we are surprised that a direct comparison should have been
made; she is 110 feet longer than Couronne, and 3300 tons
more displacement, 118 feet longer than each of the other
two, and 3600 tons greater displacement than one, and
38go tons more than the other. That these did not roll very
much more than her is due to their higher centre of gravity
and greater metacentric height.

For, comparing the French ships amongst themselves in
respect of their metacentric height, there is not even the
show of reason; for, first, the two unarmoured ships must
be struck out, as it is now admitted that they roll less than
ironclads. ‘The theory as to the contrary is now abandoned
by Mr. Reed—reason and experience have re-obtained their
sway.

The French ironclads take their places in the order of
their size, the largest rolling least. The two first are sister
ships, as also the two last, but of a lower class ; the propor-
tion of breadth to length in these last is greater than that of
the other three, therefore they ought to roll more. The

Magenta is 1100 greater displacement than the Normandie. —

Then the: Edgar* 1s said to be “inferior to the Napoleon,

* We take the metacentric height of Edgar to be the same as her sister ship,
4°6 feet.

————

1874.| Loss of Life at Sea. 489

Tourville, Solferino, Achilles, and Magenta.” ‘The inferiority
cannot arise from her metacentric height, for it is equal to
that of the Napoleon, but less than that of all the other
French ships. Why should she be inferior to the Napoleon
and Tourville ?”” Because being 3 feet wider, she is subject to
greater disturbance. The other ships are all so much larger,
especially the Achilles, that no comparison can be made;
the Achilles is 140 feet longer, and 4000 greater displace-
ment.

We take the metacentric height of Black Prince to be the
same as that of her sister ship Achilles, that of Hector
i540, and Black Prince is a. sister ship to Achilles,
and ought not, as far as we are informed, to be different
from her.

The Defence is said to be better than the Hector and
Prince Consort. With the equal length the Defence has
2 feet less breadth than the Hector, and with 7 feet greater
length she has 4 feet less breadth than the Prince Consort, |
therefore we should expect the latter to have greater motion
than either of the others.

Then the Black Prince, with her smaller metacentric
height, 3°r feet, is admitted to be inferior to the Solferino
and Magenta with their considerable height of metacentre,
one 4°5 the other 5 feet.

We have before examined the facts offered in support of
the theory as drawn from the comparison of the rolling of a
number of English ironclads, and have shown they range
themselves as respects their rolling exactly in the order of
the proportion of breadth to length, the vessel with least
proportionate breadth rolling least. The Minotaur, the
largest and best ship, with a metacentric height of 3°8 feet,
superior to the Bellerophon with only 3°2 feet of metacentric
height. The Pallas,a ship of Mr. E.]. Reed’s, the worst roller,
her smaller metacentric height not checking the rolling so
much as the great metacentric height of the Prince Consort,
Gur feet.

It was natural for Pallas to roll; she had such a great pro-
portionate breadth of plane of flotation.

Raising weight did not cure, but the contrary ; it made her
rolling worse.

Obviously the theory that induced these gentlemen to
damage a fleet of ships by reducing their stabilities has no
foundation in experience, in reason, or in science.

And as this system might have been effectually tested in
the course of an afternoon, not one of these unsafe ships
should have been built.

490 Loss of Life at Sea. [October,

Proof of Proposition stated page 478.

If, instead of supposing the floating body to be inclined at
any given angle in smooth water, we suppose the surface of
the wave to be inclined to the mean surface at an equal
angle, it will be evident that the reasoning with reference to
the pressures, pages 73 and 74, will hold good.

Mr=), Li=a, NM=c,NL=d, NO=X.

Take the usual formula for the centre of gravity, and in-
tegrating between the limits c and d—

ae fxydx
fyox
= b..
ie

Fiyds_ hot—d* _

yee 3c¢°—d’
2c*+cd+d’

3 ct+d
ct+td=24 3(c+d)=72
c’°+cd+d*

324+108+ 36= 468
a(c?+cd+d*) =936

1874.] Loss of Life at Sea. 491

6
KF.
72 "
Formula for the equilibrated lever a —a.
12

Centre of gravity of the system being above the centre
of displacement.

In this formula, b=the line of intersection of the cross
section of the floating body when upright with the surface
of the water; S, the figure of displacement when the body
is upright; a, the distance between the centres of gravity
and displacement when the body is upright.

In this case that of a block 12 feet square as described,
pase 72, &c.—

b=12 and S=6x 12.
b3

OR he
= 136
op 3 5
OP tat
BAe iat

g being the centre of gravity of the floating block f g,
evidently =06.

a=b—325=275
b?

gs Oia et Bab

The stability being negative in this case; but as the centre
of gravity is lowered, a is diminished till it becomes equal to

—_ when the stability is that of indifference ; when a is
i

b
less th
ess than 5

, the stability becomes positive and the

righting lever increases, while the upsetting lever remains
constant ; the conditions in other respects remaining un-
altered.

( 492 ) (October,

III. THE LUNAR ATMOSPHERE AND ITS
INFLUENCE ON LUNAR QUESTIONS.

By EpmMuND NEIsoNn, F.R.A.S., &c.

ERHAPS no question in connection with the condition
sof the moon’s surface has excited so much attention
as the existence, or not, of a definite lunar atmo-
sphere; and it must be conceded that it possesses the
highest importance, when considered in its relation to the
many problems of great interest to be decided in conne¢tion
with the present and past history of our satellite.

Curiously enough, although the most diligent and expert
selenographers, with hardly, perhaps, but one exception,
have long recognised both direét and indireét evidences of
the probable existence of an atmosphere, yet among astro-
nomers in general it has been usually considered as defi-
nitely established that the moon is to all intents a perfectly
airless globe. For even if it has been granted that it may
possess, perhaps, the merest trifling trace of gaseous en-
velope, it has been considered established, for a certainty,
that this must be far less dense than the most perfect vacuum
that has been artificially produced by an air-pump.

There does not appear to exist, however, sufficient grounds
for this widely entertained belief in the non-existence of a
lunar atmosphere having been proved; for apart from the
necessity, not observed in this case, of cautiously accepting
positive conclusions based entirely on purely negative results,
the subject has never been examined in a sufficiently com-
plete and accurate manner. In consequence, many of the
criteria that have been regarded as demonstrating the non-
existence of a proper lunar atmosphere should never have
been taken into consideration as applicable. Most of these
negative results, which have been relied on as showing the
absence of any gaseous envelope to our satellite, are only
applicable to an atmosphere similar in density to our own.
But such are the favourable conditions prevailing upon the
terrestrial surface that if an atmosphere whose mass and
that of the planets were in a constant ratio were to exist on
every planet, the earth’s would be far the densest of any,
excepting the giant of the family Jupiter. But on the moon
the most unfavourable conditions prevail for the density of
atmosphere; and under the conditions supposed, and these
conditions the most probable imaginable, then the lunar
atmosphere would possess at the surface a density only

—

1874.] The Lunar Atmosphere. 493

about one-fiftieth of the density at the terrestrial surface.
Notwithstanding this, however, as before stated, the ratio
between the masses of the atmosphere and planet would
be the same as onthe earth. All criteria directed, there-
fore, against an atmosphere similar in density to our own,
are quite inapplicable to the moon’s; and an examination of
any of the works treating on the question will show how
many are of this class.

Further examination will also show that we have probably
to deal with even a less density than some one-fiftieth of the
earth’s. The moon’s mean density being only three-fifths of
the earth’s, the moon’s surface is, in proportion to the lunar
Mass, over six times greater than on the earth. Accordingly
the atmosphere would be subjected to the action of a
surface more than six times as great as has been on the
earth. There can be little question but that at one time
the terrestrial surface must have exerted a powerful action
on our primitive atmosphere, and have absorbed and locked
up much of what constituted our earliest atmosphere, for
on no other conditions can be explained the known nature
of the terrestrial surface. But as the moon’s primitive
atmosphere must have been exposed to the aétion of more
than six times the extent of surface, it would appear not
improbable that her atmosphere must have lost much more
in proportion than the earth. Even, therefore, if both
planets originally possessed atmospheres whose masses, and
those of the planets, were in similar ratio, the moon’s, thus
exposed to a far greater absorbing surface, must in the end
have lost the most ; and so the residue left possess a smaller
ratio to the mass of the planet than on the earth. Wecan
easily see, therefore, how—by the action of this proportion-
ately six times greater surface—it is possible for the moon’s
atmosphere to have been reduced to one-sixth the ratio to
the mass of the planet that we find on our terrestrial surface.
It is true that this would be a very difficult question to in
any way prove, or even to maintain in its integrity, but this
is immaterial for our present purpose; and it may well be
admissible that, even had the planets started with the same
proportional atmosphere, that of the moon may have been
reduced to one-sixth. As the lunar atmosphere, under equal
conditions, has been shown to be only one-fiftieth of the
terrestrial density, reduced to one-sixth it would possess
only one three-hundredth, or possess a density expressible
on the earth as one-tenth of an inch, or some 2} millimetres.
Now such an atmosphere is possible.

But such an atmosphere is not small; the only thing

VOL. IV. (N.S.) 3R

494 The Lunar Atmosphere (October,

small about it is its density, as compared with the very
dense atmosphere of the earth, while its real magnitude and
mass is immense ; and the mass above equal portions of the
surface is not so much smaller than on the earth.

To ascertain what atmosphere is possible on the moon, it
is necessary that we should express, by means of a few
simple equations, the conditions any atmosphere would
have. As, however, the derivation of these equations from
the known physical laws, with respect to gases, would in-
volve the application of more complex mathematics, it will
be dispensed with. Throughout, it may be observed, it is
assumed that the moon’s atmosphere would be essentially
similar in composition to the earth’s, with perhaps a much
larger percentage of carbonic anhydride, which is to be
expected.

Let a = the radius of the moon in miles;

x = any height in miles above the surface ;

8, Por fo = the density, pressure, and temperature of
the atmosphere at the lunar surface, and 6, £, ¢ the same at
height x.

And put for the constants involved—

a = 0'000294, multiplied by the density of the lunar
atmosphere in terms of the standard terrestrial density of
air ;

& = 0'003665, the expansion of gases for 1° C. ;

1, = the height in miles of a column of the lunar atmo-
sphere of density 5,, at temperature ¢ that would—under
the action of gravity at the moon’s surface—exert a pressure
oi7,. Erom this—

1, = 32°6837 (1+¢7,) miles.
a
Finally, for brevity, write 6 for i:

Then the equations expressing the physical condition of
the lunar atmosphere may be written—

ei We pacer =k «= we

Where ¢ is the base of the natural logarithms—

—u

6 = K€ vk, ee Gk ue ee a
b= $,8, Gaffe a ee
E--et _

rf (rae) CEU roses ee

ee Pt

1874.] and its Influence on Lunar Questions. 495

And lastly, for the horizontal refraction 7,, expressed in
seconds of arc, undergone by a ray of light in passing through
the atmosphere—

r= GAO) /O8l 1 (fas) (Ya) Hf %)} »
sin I
where f is the function on which the rate of decrease of
temperature depends.

Were the temperature of an atmosphere constant through-
out, the density and pressure would, in accordance with
Mariotte’s law, diminish together in geometrical proportion
with increase of altitude. The temperature is, however,
not constant, but varies inversely as the altitude; so it be-
comes necessary to assume some law for this decrease, and
this will evidently depend primarily upon the supposed tem-
perature of space. It has been generally assumed, by those
who have lately written on this lunar subject, that the tem-
perature of space is near the absolute zero of heat,—in
contradistin¢tion to Fourier and Hopkins, who regarded it
as but little below zero, which is preferable. Whatever
value may be adopted, the corresponding value of the
function f is given by the equation—

eles
uf Eero jae (6)
as the temperature of space would not be reached until a
considerable distance from the moon.

These equations, it is seen, involve the temperature of the
lunar surface, and from Lord Rosse’s determinations it ap-
pears that the moon’s surface may reach 200°C. For the
minimum value the temperature reaches during the long
lunar night very different values have been ascribed, and it
is evident that much may depend on the temperature of
space assumed. It has, moreover, been generally thought
that any lunar atmosphere would, from its extremely small
density, exert little influence in retarding the radiation of
heat from the moon; but it has been overlooked that the
thickness of the envelope of atmosphere, as well as its
density, must be considered. Now the thickness of the
lunar atmosphere is for this purpose many times greater
than the earth’s, and this counterbalances its tenuity; ac-
cordingly the retardation of radiation would not be much
less than on the earth. As during our long terrestrial polar
nights, from six to ten times the length of the lunar night,
the mean temperature is not usually many degrees below
zero, it will therefore be probable that the temperature of

496 The Lunar Atmosphere (October,

the moon’s face will not fali either much below zero, for
there is more heat to be lost than onthe earth. It is, more-
over, to be remembered, that the proportion of carbonic
anhydride in the moon’s atmosphere would be probably much
greater than in the earth’s, and this powerfully retards the
radiation of heat. From these considerations, then, we have
at sunrise the moon’s surface at any position near the
equator, the temperature about —20°, which will increase
until a little after full moon, when it will have risen to
about 200°, and will then slowly decrease, until at sunset it
will be about 60°. During the lunar night the temperature
will fall slowly until a few days before sunrise, when it may
become as low as —30, rising again to about —20° at sun-
rise. But it is evident that as the temperature is solely due
to the solar rays, these must be the extreme results; and
that for any place away from the lunar equator the climate
will be much milder, never rising to so high a temperature,
as the sun will not be in its zenith, nor ever falling so
low.* This circumstance has usually been overlooked.

The temperature of the lunar surface having been there-
fore approximately determined, the equations can be at once
applied to find the conditions of the greatest lunar atmo-
sphere possible under known circumstances.

An examination of all the methods that have been applied
to detect a lunar atmosphere shows that all the most delicate
—and, in fact, only applicable ones, to such an atmosphere
as we have seen would probably exist—are based upon the
refraction of light by the atmosphere. And the condition
under which this refraction is most marked is that which
requires attention, namely, the horizontal refraction. And
even of these selected methods, the most delicate and only
thoroughly reliable one is that based on the retardation of
the occultation of a star, at the dark limb of the moon, by
the refraction caused by the light traversing the atmosphere.
For when the diameter of the moon is known, the exact

* The values in the text are arbitrary, but have been arrived at from theo-
retical consideration in conjunction with Lord Rosse’ determination, and can
be expressed by the following equation, which gives the theoretical results for
the maximum and minimum taken. Assume © is the solar altitude at any
spot, and increases from o to its maximum, and then falls to 0, at which it
remains while the sun is beneath the horizon. Put ¢ equal to 300 degrees at
sunrise, and rising uniformly by 27 during each lunation; then if X be the
latitude of the spot we have roughly—

to = 170°(1-Acos + Bsin € —C sin X).
It has been taken that A=o'g. B, which varies as the cosine of the latitude,
is 0°28 at the equator, and C = 0°08, which values but represent the theoretical
probabilities.

1874.] and its Influence on Lunar Questions. 497

time of the disappearance of the star, were there no
atmosphere, is easily calculated; and if, therefore, it is
found that the observed time of occultation is later than
the calculated, then a lunar atmosphere—of a density that
would cause this retardation—appears certain.

Unfortunately the moon’s diameter is not known with
exact accuracy for certain, although it is so within very
small limits; and this somewhat complicates matters. Sir
George Airy has determined, from transit circle observations,
what is regarded as a very accurate value for the moon’s
telescopic semi-diameter. This value has been considered
very slightly too great, owing to the effect of irradiation at
the lunar limb caused by the contrast between the bright
moon and the sky; although a careful examination of the
observation of the lunar diameter shows that this is ques-
tionable, and renders it doubtful whether the variation found
with different instruments is not due solely to the spurious
telescopic disc.

Observations made with the Great Equatorial, at Green-
wich, during the solar eclipses of July, 1860, and December,
1870, enable this to a great extent to be rectified, by showing
the minimum value for the lunar semi-diameter to be some
15’ 34°00’—a value in agreement with the observations of
Greenwich and Oxford. For it is apparent that during >a
solar eclipse there is an absolute reversal of the effects of
irradiation, as they must then—to a much greater extent—
diminish the apparent diameter of the moon than under
ordinary conditions they can ever increase it,—as the con-
trast between the dark moon and the extremely bright disc
of the sun is vastly greater than the contrast between the
comparatively feeble light of the moon and the sky. More-
over, as the point to be determined in observation during a
solar eclipse is where darkness ceases, we have absolutely
the fullest action of irradiation, together with the effect of
a maximum spurious telescopic disc; while under ordinary
conditions vf observing the moon’s limb with the transit
circle a smaller spurious disc comes into play, and it is
questionable whether the effect of irradiation on these ob-
servations has not been over-estimated. In, therefore,
observations of a solar eclipse the moon’s apparent diameter
is reduced to a much greater extent than under ordinary
conditions it can ever be increased; and we have, accord-
ingly, the value for the moon’s minimum diameter before
stated.

The minimum lunar semi-diameter may be considered as
15/ 34°00”, although it is possible that the true diameter is

498 The Lunar Atmosphere (October,

somewhat larger, as indeed is indicated by the observation
made during the eclipse of 1870, the most favourable one of
the two. It remains now to see whether, with this lunar
semi-diameter, the observed occultation of stars by the
moon’s dark limb indicate the presence of any lunar atmo-
sphere; for the occultations at the bright limb are very
inferior, and the re-appearances at both limbs are almost
valueless.

From a large number of observations of occultations of
stars by the moon—made between 1850 and 1873 when very
satisfactory lunar places had been obtainable, and observed
at Greenwich, Oxford, and Cambridge—it has been shown*
by the author that the lunar semi-diameter derived from the
occultations at the dark limb of the moon is less than the
adopted minimum semi-diameter by over two seconds of arc,
corresponding usually to from five to ten seconds of time.
The retardation of an occultation being less than twice the
horizontal refracétion,t this would indicate the existence of
an atmosphere exerting a horizontal refraction of a little
over one second of arc; and the possibility of its existence
appears beyond question, for no other method of detecting
an atmosphere approaches this in delicacy.t

The equations on which the physical conditions of the
moon’s atmosphere depend may at once be employed to find
the density of a lunar atmosphere whose horizontal refraction
will be a little greater than one second at the tempera-
ture of about zero. By putting the density of the moon’s
atmosphere at about one three-hundredth of the earth’s, it
will be found to satisfy this condition, keeping the value of f
moderate. It will also be found that, as the average tem-
perature of the moon’s bright limb is high, the refra¢tion
exerted by the atmosphere is only about one-half of that at
the dark limb; and, if allowance is made for the effects of
the spurious telescopic disc at whose edge the star will dis-
appear usually, it will be found that the observations of
occultations at the bright limb give agreeing results.

The great difference in the density of atmosphere
arrived at for somewhat similar retardation of occultation—
for Sir George Airy has long seen the possibility of an atmo-

* Monthly Notices of the Royal Astronomical Society, vol. xxxiv., p. 356.

t+ In the Monthly Notices, vol. xxxiv, p. 20, the late Sir John Herschel’s
value has been taken, but it has since been found that the above is correc.
This requires the suppression of the first sentence of the bottom paragraph of
that page.

t That further discoveries and observations may possibly modify this con-
clusion is of course unquestionable, but this constitutes no reason for altering
any deduction to be drawn from the circumstances as they exist at present.

1874.] and its Influence on Lunar Questions. 499

sphere being the cause of this—arises from a very simple
cause. From merely looking at the question in a general
manner it has been always considered that for a similar
surface density the refraction on the moon and earth would
be alike ; but a mere inspection of the complete differential
equation to the refraction of light through an atmosphere
shows that the refraction for equal surface densities varies
approximately for small refraction as the square root of the
radius of the planet and the action of gravity on the surface,
and on the moon both, are much lessthan on the earth. On
the moon accordingly, for equal surface densities, the
refraction is only about one-fifth of what it would be on the
terrestrial surface, and, this circumstance having been over-
looked, the density of the atmosphere has been greatly under-
estimated.

It would be useless to travel through the numerous
methods that have been referred to as showing the non-
existence of any lunar atmosphere, not of much greater
tenuity than the most perfect vacuum of an air-pump, for
they are not applicable to such an atmosphere, although it
could hardly be called even a vacuum, much less a perfect
air-pump vacuum, but a few general remarks will suffice.
The effect of the atmosphere on the phenomena presented
by the moon would be imperceptible in all except the single
case of the retardation of occultations, for the amount of
refraction is insufficient to in any way distort or alter the
appearance of a star or planet seen through it, and, similarly,
any effect it might exert upon the spe¢troscopic observations
of our satellite would be marked by the greater action of the
terrestrial atmosphere. The sole action it would exert
during a solar eclipse would obviously be to simply augment
the solar diameter to a very slight extent, but, as this latter
is not known with accuracy, this would be undetectable;
neither would any new lines be revealed by the spectroscope
in observations like Mr. Stone’s,* for there would be no new
substance to give them, as would be indeed very improbable.
Finally, it may be observed that the rays, after refraction
through the atmosphere, would not be convergent like after
passing through a lens, for, the refraction diminishing with
the height, rays from different altitudes would be divergent.
This atmosphere, which at first sight might appear so rare
as to be unworthy of notice, is not so in reality, for it is of
much greater proportionate dimensions than the earth’s,
which it even exceeds in actual volume, counterbalancing its

* Monthly Notices of the Royal Astronomical Society, June, 1874.
yi.

500 The Lunar Atmosphere [Otober,

less density. Consequently, the amount of atmosphere
acting on the moon’s surface is not much smaller than on
the earth, and, as far as a single square mile of surface is
concerned must be estimated by millions of tons. Moreover,
from these considerations as to the horizontal refraction
exerted by a lunar atmosphere, it is evident that, were its
density a little less than one-thousandth of the terrestrial
density, the retardation at the limb during occultations would
no longer be detectable from its being smaller than the
probable errors of the method, and yet it cannot be questioned
but that this atmosphere would still exert a most marked
influence on the physical condition of the lunar surface.

There are many selenographical problems dependent on
the question of the existence or not of a lunar atmosphere,
and prominent amongst them stands the absorbing subject,
so often debated, oflunarchanges. Though the configuration
of the surface of the earth is undergoing a never-ceasing
change from the action not only of volcanic forces, but also
of the various atmospheric and aqueous causes, were it to
be regarded from the moon, it is doubtful whether during
the last century, with all our telescopic aids, any unmistak-
able alteration in the formations constituting it, or in its
appearance even, apart from changes of tint, could be detected.
Similarly on the moon there may be even more energetic
action in constant work, without its making such vast
changes in the appearance of our satellite as to direct our
attention unmistakably to the circumstance of lunar,
volcanic, and other energies being still in active progression.
For such is our imperfect knowledge of the details of .the
configuration of the surface of the moon, that, were at
intervals of a few years new volcanic cones, craterlets, and
hills to come into existence, it is improbable in the extreme
that they would be recognised as new formations instead of
new objects detected.

Suppose the new manifestation of lunar volcanic energy
took the form of some of those volcanic cones, as occur on
both the earth and moon—a steepish hill, some hundred
yards in diameter and hundred feet high, with a deep mouth
of no great dimensions; or else, perhaps, gave rise to a new
ridge of mountains, such as are so common on the moon,
some miles long and a mile broad, covered, perhaps, with
small crater cones not exceeding some hundred yards in
dimensions—there is not one ten-thousandth of the moon’s
surface where these new formations would possess the
slightest probability of being taken for the result of the action
of present lunar volcanic energy. Or were, from some vast

1874.] and its Influence on Lunar Questions. 501

convulsion, a magnificent lunar crater to be formed, and
cover the surface around with streams of lava, with a mouth
two thousand yards in diameter and a thousand feet deep,
its discovery would be improbable—nay, unless it occurred
close to some few small localities, it is almost certain that
it would not be detected as a new formation. Assuming,
however, that one of these new formations were to appear,
or some craterlet a thousand feet deep and several miles in
diameter collapse into ruins, and granting one or two of the
very few astronomers who study the moon’s surface had for
years sufficiently studied the small portion of surface where
it occurred as to be sure it was a new formation, it would
then be found impossible to prove it to other astronomers.

The actual effects of libration on the moon, in ever
presenting the objects on its surface in new lights and at
different angles, makes the lunar formations always variable
in appearance to some extent ; while the general opinion of
the powers of libration to change the appearance, visibility,
and form of lunar objects, even near the lunar centre, is such
that the most marked changes of appearance are ascribed to
its effects. It would therefore require a most striking and
wonderfully marked difference in the appearance of a large
lunar formation to occur, before the existence of lunar
volcanic, or other inherent energies would be admitted as
demonstrated, or perhaps probable. There is, in fact, a
certain amount of basis for this reluctance to admit the
existence of lunar changes, for certainly the difficulty in the
study of the details of the moon’s surface is such as to render
great caution necessary; but it must not be overlooked, as is
commonly done, that this in itself prevents the absence of
any proved case of change in the lunar formations being
accepted as a complete demonstration of the cessation of the
action of all volcanic and similar forces on the surface of the
moon.

Those astronomers who have made the details of the
surface of the moon their study, are well acquainted with
the almost absolute want of knowledge of the real minute
details of the surface, and accordingly have long been
convinced, with perhaps the exception of Beer and Madler,
that we are without any evidence of the constancy of the
configuration of the moon’s surface, with one exception, and
this bar to the possibility of the moon’s volcanic and other
sub-lunarian energies being still actively at work was the
supposed absence of an atmosphere. Volcanic a¢tion and
no atmosphere seems inconceivable, as De la Rue has long
remarked, but, grant the existence of the lunar atmosphere,

VOL. IV. (N.S.) 38

502 The Lunar Atmosphere (October,

and at present there is no evidence that the moon’s volcanic
energies are not tenfold more active than on the earth, and
the importance of the determination of the probability of a
lunar atmosphere is evident.

There is another question which is completely controlled
by that of a lunar atmosphere. Most selenographers, and
even the most cautious, Beer and Madler, have recognised
on the moon indications of the existence of some form of
vegetable life, but, again, vegetation and no atmosphere is
inconceivable ; waiving the question of moisture as carrying
us into too large a field, and granting the existence of an
atmosphere, and most interesting problemsare opened. For
the researches of M. Paul Bért have shown that vegetable
life is possible under atmospheric pressures only one-twentieth
of the normal terrestrial one, and not so much more than is
possible on the moon ; considering, therefore, the wonderful
adaptability to circumstances of vegetable life, who can say
it is impossible at a pressure less than this? The moon’s
temperature need be no bar, for, although a fatal objection
near the equator, it is no longer so nearer the poles.

Similarly with the many more recondite problems that
the study of the moon’s surface has given rise to—the streaks
and rays of the full moon, the variability of the markings,
floor, and craterlets of Plato, the white cloud-like coverings
of Linne and y Posidonius, the difference in the polarisation
of the light reflected from the plains and mountains observed
by Secchi, in their photographic power found by De la Rue,
in their colour by Birt, in their visibility by Schmidt—all
involve in their consideration the question as to the existence
of a lunar atmosphere. It must be at once admitted that
the existence of a lunar atmosphere facilitating the probable
explanation of these phenomena proves nothing; for the
circumstance, that granted a basis and all can be explained,
is no demonstration of the truth of that basis. But neither
must it be assumed, as is so often done, that the possibility of
accounting for phenomena on other grounds shows the
proposed explanation to be probably wrong; the nature of
the two must always be considered. For example, it is
possible to explain the photometric results of Zollner as to
the brightness of the moon by assuming either that the lunar
surface is covered by a multitude of very minute steep
conical hills, each of a definite slope, and arranged in a
complex manner round two common foci, or else that it is
covered with extremely small regular furrows of uniform
angle, running from pole to pole at proper distances; and
these hypotheses explain most satisfactorily all Zollner’s

1874.] and its Influence on Lunar Questions. 503

observations ; but they cannot be considered as disturbing
the explanation that the cause of the phenomena in question
is simply the known irregularities on the surface, which also
accounts for the observations, although not so well. It is,
however, too generally considered that the possibility of two
explanations of one circumstance weakens the probability of
both.

Competent dealing with the problem of the physical
condition of the surface of the moon requires a special
knowledge of the minuter details of the lunar surface, rarely
met with in combination with a proper acquaintance with
the more theoretical elements involved in the subject, and, in
consequence, questions have often been considered as
standing in a different position to their real nature. A mere
general familiarity with the principal configuration of the
moon’s surface and the phenomena to be seen is not sufficient
in the hands of the most able theorist for the proper con-
sideration of the complex problems involved, and it is not
strange if the resulting conclusions are often not all that
could be desired.

The study of the details of the moon’s surface, until very
recently long left in the hands of a very few indefatigable
astronomers, from the interest inseparable from it is now
attracting the more general attention it demands, and gives
promise of before long placing us in a more satisfactory
position with regard to the nature of the lunardetails. The
admirable work of Beer and Madler, so far from being
exhaustive as was long thought, brought us to only the
threshold: Schmidt’s forty years’ work, gigantic as are the
results, only reaches the minutiz, and will require years of
revision; while the real character of the objects now known
to exist merely, is nearly untouched ground, and it is there
where some of the greatest difficulties will be felt, for to
evolve a theory as to their source is far different from
detecting their true origin. But there is promise ere many
years are over that we may be in possession of a sufficiency
of exact knowledge of the features presented by the moon to
enable some more satisfactory conclusions to be drawn as to
the events of the past history, present condition, and
immediate future of our satellite.

( 504 ) (October,

IV. BERYLS AND EMERALDS.
By Professor A. H. Cuurcu, M.A., &c.

‘Xi LTHOUGH to the mineralogist the stones known as
ah aquamarine, beryl, and emerald, constitute but one
species, there are decided differences of optical pro-
perties, as well as minute differences of chemical compo-
sition, between them. Under the name “ beryl” minerals of
considerable variety of aspect are thus included; some spe-
cimens being nearly opaque and brownish-yellow, others
being perfectly transparent and colourless, while others,
again, are beautifully tinted with a pale sea-green hue.
But other colours also occur, such as yellowish-green, pale
blue, and even lilac. Still it is in the emerald, once thought
to be a distinct mineral species, that the richest and most
highly appreciated colour is found. The pure green of this
gem has provoked several enquiries as to its nature, and,
quite recently, Mr. Greville Williams* has taken up the
enquiry, and published the first portion of his results. In
presenting an account of this research to our readers, we
will also give some fac¢ts derived from other sources con-
cerning the transparent beryl and the emerald.

This mineral species occurs only in crystals, while such
divergences from constancy of composition as it exhibits
affect scarcely more than 2 parts out of 100 in any specimen.
It is essentially a silicate of alumina and glucina, but it
always contains a little iron, while chromium seems a con-
stant ingredient of the true emerald, though occurring as a
trace merely, not amounting to a half per cent when calcu-
lated as sesquioxide. Other metals have been recognised in
some varieties of the beryl by different analysts, and the
list will include calcium, magnesium, manganese, and
tantalum.

The specific gravity of transparent pale beryls is, as
nearly as may be, 2°7, so that it is decidedly denser than
rock crystal. This fact may be beautifully illustrated by
means of a solution of mercuric iodide in potassium iodide.t
Such a liquid may be readily obtained with a sp. gr. = 30,
but a solution not denser than 2°67 or 2°68, nor lighter than
2°665, is required in the particular case in point. In such
a liquid a piece of flawless rock crystal floats, for its specific

* Proc. Roy. Soc., No. 145, 1873.
+ Recommended by Mr. E. Sonstadt for such experiments, in the ‘‘ Chemical
News,” vol. xxix., p. 127.

1874.] Beryls and Emeralds. 505

gravity is but 2°652 at the most, while all beryls, when free
from any kind of imperfe¢tions, such as cavities, fissures,
&c., appear to range in density from 2°69 to 2°705, and con-
sequently sink. The same is true of the emerald when
perfect, but the general presence of internal flaws in this
stone, even though they may be very minute, lowers its spe-
cific gravity decidedly, and may even reduce it to that of
rock crystal. It should be stated here that the specific
gravity of beryl is not altered by any temperature short of
that necessary to effect the fusion of the stone, and thereby
to change its crystalline structure to the condition of a
glass.

A word concerning the hardness of beryl will suffice.
Pure, transparent, and colourless or pale specimens are
harder than quartz, varying from 7°5 to nearly 8; yet the
best emeralds—though they scratch quartz, and of course
all kinds of glass and paste as well—are slightly softer than
the paler varieties of the species, such as the aquamarine.

We now come to the question of the colour of the
emerald, a question which has been lately studied with par-
ticular care by Mr. Greville Williams. The green hue of
this gem is of a different quality from that of the precious
beryl and the aquamarine,—indeed it closely approaches, in
really good specimens, to the pure green of the solar
spectrum. The colour is, also, far more permanent than
that of some beryls, especially those of a yellow or greenish-
yellow hue, which become bluish, or even pale blue, when
heated before an ordinary gas blowpipe jet, long before they
show any signs of incipient fusion. The emerald, on the
other hand, when heated alone before the oxyhydrogen blow-
pipe, bears a bright red heat without loss of colour, and
even when it begins to fuse the edges only become colourless
and opaque, the centre remaining green. Even when fused,
emeralds are kept at the maximum temperature attainable
by means of the oxyhydrogen blowpipe, they retain an
opalescent dull green hue for some time, and it is only after
prolonged heating that they become at last transparent, and
almost free from colour. Greville Williams has also found
that the addition of chromium sesquioxide to a fused
emerald bead which has become colourless produces only a
dull green colour, or, at the best, a colour decidedly inferior
to that of the emerald. Cobalt oxide gives a fine blue tint
when similarly added to an artificial mixture having the
composition of the natural beryl or emerald, and this blue
colour is not altered by the high temperature of the oxy-
hydrogen flame. With such artificial beryl composition

506 Beryls and Emeralds. [October,

other coloured glasses may be made, one of the most inte-
resting of these being that containing didymium oxide,
which imparts a.lively pink colour to the fused bead.
Moreover, this beryl glass shows the black absorption spec-
trum of didymium in a very perfect manner. The artificial
beryl-glasses were made by taking the essential constituents
of the mineral in the percentage proportions here given :—

DALICALS inui nacgh) Go eel gehen Bee
ALUMINA ¢. st Gah octets Sete
Giueinar, 05) hs.) a9 “ovaghie eens

I00°O

By the fusion of these ingredients together a beryl-glass is
obtained which is pra¢tically identical in physical and
chemical charaé¢ters with that resulting from the fusion of
the native emerald or beryl. In each case the hardness is
reduced below 7 (that of quartz), and the specific gravity is
only 2°42 instead of 2°7. These are signs that the com-
pound has passed into the vitreous condition, and that it is
destitute of crystalline structure. Though really identical
in chemical composition with the native beryl, these beads
are nothing more than “ beryl-glasses,” and can never in
such a condition compete with the true native stones. Even
were the exact tint of colour to be achieved, and if the
hardness and specific gravity of the artificial glasses were
much increased, still there would remain one fatal inferiority
to the true emerald. For an emerald is dichroic, exhibiting,
when viewed along the principal axis of the crystal, a green
hue decidedly dashed with yellow, while when viewed in any
direction transverse to this it shows a green colour verging
a little towards blue. The instrument known as Haidinger’s
‘*‘dichroiscope”’ enables these two pencils, of differently
coloured (and differently polarised) rays, to be seen alongside
of each other if a beam of white light be transmitted
through the crystal along one of the secondary axes. Now
the crystalline structure upon which this dichroism depends
has not yet been imitated in the artificial emerald, and in
consequence the play or fluctuation of three hues—the
normal emerald-green, the yellowish-green, and the bluish-
green—of the natural crystal must be wanting in any
vitreous imitation of it. This dichroism of the best emeralds
is often seen when a number of small gems have been cut
from a single crystal of apparently uniform colour; some of
the polished pieces, having been cut in a different direction
with regard to the axes of the crystal, will show decided

1874.] Beryls and Emeralds. 507

variation in hue. The dichroism of other coloured beryls,
as well as the emerald, is often well marked.

One of the main objects for which Greville Williams’s
research was undertaken was the settlement of the relation
between the so-called organic matter found in the emerald
and the colour of the stone. By an ingenious arrangement
of apparatus, and by the use of the chromic acid method of
burning the carbon and hydrogen present, this chemist has
shown that colourless beryls sometimes contain carbon and
hydrogen, just as the emerald does; and he has demon-
strated that the carbon does not exist as a carbonate, though
it may possibly occur in the form of microscopic diamonds.
We are promised a further contribution to the chemistry of
the emerald, with especial reference to the modes of sepa-
rating and estimating the rare earth, glucina, which it—in
common with the chrysoberyl, another mineral used in
ornamental jewellery—also contains. The chemist Loewy,
who believed the colour of the emerald to be due to organic
matter, detected the earth glucina, to the extent of 4 per
cent, in the calcareous concretions which are associated
with the matrix in which the mineral is found at Muzo,
New Granada: pyrites, and the rare carbonate of the
cerium metals known by the name of Parisite, also occur
with the emerald. It would be as well to examine the
Brazilian emerald for cerium and its allies.

The emerald is more prized now than formerly, as much
as £40 having been given for a perfect emerald of 1 carat
(0°20541 of a gramme, or 3°17 grains). An emerald of
I carat, owing to its low specific gravity, is of course much
larger than a sapphire of the same weight, and about one-
third larger than a diamond. Large emeralds are seldom
of uniform and deep colour, and hardly ever free from
numerous cavities and flaws. In the Duke of Devonshire’s
collection there is a splendid crystal, about 2 inches in each
direction, and weighing nearly 9 ounces troy, but it is much
flawed. Inthe Green Vaults of Dresden there are some fine
stones, while there are also numerous specimens in the
Brazilian, Turkish, Portuguese, Austrian, Persian, and Papal
Treasuries. Many of these have, however, been disfigured
by perforations or inartistic engravings, and being in many
cases merely rounded and polished, ‘‘ en cabochon,” are not
capable of showing to full advantage those optical properties
of dispersion, refraction, dichroism, &c., which may be deve-
loped by the judicious cutting of this gem. In the South
Kensington Museum, among the rings of the Townshend
collection, is a superb emerald, step-cut, and showing the

508 Curved Appearance of Comets’ Tails. (October,

characteristics of this stone inan eminent degree. The small
so-called emerald of the Hope colle¢tion, in the same Museum,
is nothing more than a piece of green glass. The true
emerald is not well adapted for the purposes of the cameo
and intaglio cutter, and was seldom engraved in Europe,
although some examples exist,—as the Duke of Buccleuch’s
fine Medusa’s head on emerald (a Florentine work of the
seventeenth century). In Persia, India, &c., on the other
hand, engraved or at least inscribed emeralds are not un-
common. But the transparent beryl and particularly the
aquamarine have frequently been engraved with great skill
and beautiful effect, both in classic and later times. Several
good specimens of this kind are preserved in different public
and private collections of gems, both in England and on the
Continent. In the Bibliothéque Nationale of Paris there is
a fine cameo of Julia, the daughter of Titus: the British
Museum possesses some beautiful engravings on the same
material, and there are others in the Museums of Florence,
Naples, &c.

Some perfectly transparent and flawless aquamarines
have been found of enormous size. One Brazilian stone
weighs 225 troy ounces, and is as big as the head of a calf!
The writer of this notice has seen one in London, of a rough
spherical form, of perfect purity, though pale in tint, and
nearly 4 inches in diameter. Mr. Hope possesses, in the
hilt of Murat’s sword, an aquamarine of remarkable size:
there is also a fine richly-coloured stone amongst the Crown
jewels in the Tower. In many private collections and in
public galleries the different varieties of the beryl may be
found in abundance: there is a good series of specimen
crystals in the Mineralogical Department of the British
Museum.

V. ON THE CURVED APPEARANCE OF
COMETS’ TAILS.

By Lieut.-Col. Drayson, R.A., F.R.A.S.

es
Ae our paper on the Pole Star and Pointers in this Journal,
i] we called attention to the fact that what would appear
as a straight line to an observer in one part of the
world, would appear as a curve or arch in the heavens to
an observer on another part of the earth’s surface.
As an illustration of this law, we called particular attention

1874.] Curved Appearance of Comets’ Tails. 509

to the trace of the equino¢ctial on the sphere of the heavens,
and pointed out how to an observer in middle latitudes
the equinoctial would appear like an arch, cutting the east
and west points of the horizon, and rising on the meridian
to an altitude equal to the colatitude of the station on which
the observer is located, whilst to the individual at the
equator the trace of the equinoctial would appear as a
straight line, rising from the east and west points straight
to his zenith. Again we showed that to an observer at
either pole the equinoétial traced in the heavens would
coincide with the horizon, and would again appear as a
straight line. It was also shown that a great circle passing
from the east and west points of the horizon and through
the pole would, for that part above the horizon and visible,
appear as an arch to an observer in middle latitudes.

We will now suppose that three stars or any three
celestial bodies (distant from the earth many million miles)

R

H 0 Z

were located on the equinoctial; that to an observer at the
earth’s equator these three stars, which we will call P, R, s,
were so situated that the star R was at the zenith, the star
p east, and the star s west of the observer, and both 45°
above the horizon. These three stars being coincident
with the equinoctial would appear in a straight line to the
observer at the equator, and the line joining P R s would
also appear as a Straight line.

To an observer in, say, 51 north latitude, the equino¢tial ap-
pears as an archor curve in the heavens and not asa straight
line, and all portions of the equinoctial appear as portions
of an arch or curve, and therefore the line joining the three
stars, P RS, would appear as an arch orcurve to the observer
in lat. 51°, though it would appear a straight line to an
observer at the equator. The three stars on the equino¢ctial
would appear curved to an observer in lat. 51°, as shown in
the diagram, where H is the east, z the west points on the

VOL. IV. (N.S.) 3T

510 Curved Appearance of Comets’ Tails. [O&tober,

horizon, HP RSZ a portion of the equinoctial, and PRS
three stars on the equinoctial. The line P RS will appear
as a curve or arch.

We will now suppose that s is the head or nucleus of a
comet, and that the tail extends along the equinoctial and
as faras Pp. The comet’s tail would now reach from P to
R and s, and would appear as a curved line or arch to an
observer in 51° latitude and to observers in all middle
latitudes, but as a straight line to an observer at the equator,
or to one at the North Pole. Consequently the curving or
bending of a comet’s tail is in this case an appearance only,
due to the position of the observer, and the same comet’s
tail may appear at the same instant to two observers, one
in middle latitudes and the other at the equator, as a curve
and a straight line.

When the comet’s tail is extended in that part of the
heavens near the North Pole, a quarter rotation of the earth
will produce similar effects to the preceding. Asan example,
suppose the head of a comet west of the pole and the tail
coincident with the great circle passing from the west point
on the horizon through the pole, then the tail being
coincident with this great circle would appear curved.

In six hours the comet would be on the meridian and
below the pole, and the tail being coincident with this
meridian, would now appear as a straight line, whereas
before it appeared as a curve. ‘Thus the curvature of a
comet’s tail is an appearance only, and is due to the same
law as that which causes the pointers to sometimes appear
to point more dire€tly towards the pole star than they do at
other times.

During the year 1861 we happened to be staying in
Hampshire with a friend who was a close observer of
Nature. We were walking in a wood a few minutes before
sunset, when happening to look at the sky through an
opening in the trees, we remarked a bright object larger
than Venus at her greatest brilliancy. The object we at
once saw was in the north, and we therefore knew that it
was no star or planet which had so brilliant an appearance,
and before the sunlight had sufficiently decreased to show a
tail, we had decided that a remarkable comet must have
come suddenly upon us.

As the sun descended below the horizon and darkness
stole over the scene, the comet’s tail became visible, and
stretched from the nucleus, which was below the pole
and near the northern horizon to far up above the zenith
and over towards the south. By means of a pocket

1874.] Curved Appearance of Comets’ Tazis. 511

sextant, which we had with us, we measured the length of
the tail by measuring from the disc of the comet to those
stars which could be seen within the tail. We found that
110 was the length of the tail, and we noted those stars
which appeared to be in the centre line of the tail.

At about four o’clock in the morning our friend called
us to come and look at the comet, which he announced
had undergone a marvellous change.

When we first saw the comet and up to nearly midnight
the tail appeared straight, and to point past the pole and
up to the zenith; but at 4 A.M. the comet’s tail had quite
altered its shape, and, as our friend remarked, was more
curved than a Turkish scimitar. Being aware at the time
of those laws of curves and straight lines demonstrated in
the preceding papers, we saw how good an example this
comet afforded of the laws, for it was a practical illustration
of a straight line becoming in appearance a curved line in
consequence of six hours of diurnal rotation. We remarked
that the comet’s tail had not changed its position in the
heavens as regards the fixed stars in the slightest degree,
the very stars that were in the centre of the tail at Io P.M.
were also there at 4 AM.; and, in fact, we had the same
problem exhibited in the heavens as we have endeavoured
to demonstrate by diagrams in the preceding papers. The
particular position occupied by the comet of 1861 was such
that in six hours it changed the apparent form from a straight
line to a curve, as seen by an observer in England, the
comet’s tail being directed from the northern horizon past
the pole and zenith. If this comet instead of being so
situated had its tail coincident with the equino@tial, it would
never have appeared to us in England as a straight line,
but always as a curve in the heavens during the whole time
it was abovethe horizon. If, however, it had coincided with
the equinoctial it would have appeared as a straight line to
an observer at the equator of the earth, and never as a curve
orarch. Thus, whether a comet’s tail appears as a straight
line or as a curve depends mainly on the position of the
comet in the heavens and on the position of the observer
on the earth. If a comet’s tail were coincident with the
equino¢tial, and of, say, 80° length, it would appear to an
observer in 45 N. lat. as a curve or arch. If this observer
could be instantly transported to the equator, the comet
would then appear as a straight line without any sign of
curvature. If,again, the person were transported to 45’ S. lat.,
the comet would again appear as a curve. A _ comet,
therefore, that coincides with the equino¢tial appears as a

512 Curved Appearance of Comets’ Tails. (October,

curve or a straight line, according as the observer is at one or
another part of the earth, whereas a comet whose tail passes
through the pole appears as a straight line or curve, ac-
cording as the tail is directed towards the zenith or towards
the east or west. Thus rotation in the last case produces
the same effect as a different position of the observer pro-
duces in the case of a comet on or near the equinoéctial.
We need scarcely add that the same law holds good for
nearly every part of the heavens.

The reader who has carefully read the preceding remarks
will be enabled to state exactly those conditions under which
the tail of a comet will appear a straight line or@ curve.

It must be borne in mind that the fact of a comet’s tail
appeaying as a curve or arch to an observer on earth does
not in the least prove that the tail of the comet is actually
curved; it may be perfe¢tly straight, and will yet appear as
a curve from the reasons assigned.

There seems to have been some obscurity in the minds
of former writers on. astronomy on this subject of the
curves of comets’ tails, for we find the following statements
relative to this curvature in the undermentioned works :—-

‘The tails of comets, too, are often somewhat curved,
bending in general towards the region which the comet has
left, as if moving somewhat more slowly, or as if resisted in
their course.”—From Herschel’s Outlines of Astronomy, Article

‘‘The tails (of comets) appear to stream from that part
of the nucleus which is furthest from the sun but seldom in
the direction of a straight line joining the two bodies. They
generally exhibit a sensible curvature.”’—IFvom Gallery of
Nature, page 112.

*““P. Bienewitz, better known as Apian of Ingoldstadt,
concluded from what he ascertained in the instance of the
comet of 1531, that the tails are always opposite to the sun
and in the direction of a line joining the centres of the sun and
the comet; but more exact observation shows that as comets
approach their perihelion the tails are gradually bent more
or less towards the region they have left, as if there were a
resisting medium. ‘The tail of the comet of 1689 assumed
the form of a Turkish scimitar; and that of the comet of
1744 was bent like a quarter of a circle.’—From Smyth’s
Celestial Cycle, vol. 1, page 221.

*“ If no comet ever exhibited any other than this peculiar
form of tail straight and directed from the sun, we might
frame an hypothesis which could account for the facts; but
in some instances there are many tails to the one nucleus,

ee ee

1874.] Curved Appearance of Comets’ Tails. 513

and these not straight but curved like a scimitar.’—From
Popular Astronomy. By O. M. Mitchell, LL.D.

It is interesting to find how much attention has thus been
given to the fact that comets’ tails are usually curved ; but
it seems that the geometrical laws which cause this curving
have escaped observation. There is, however, one advantage
derived from the problem, viz., that it appears it has pre-
vented some hypotheses from being framed to account for
what was supposed but did not occur.

It is most essential that before we invent a theory to ac-
count for what we see, we should be certain that we are not
misled by mere appearances. We have demonstrated the
cause of a comet’s tail appearing in the heavens as a curve
to one observer, whilst it appears at the same instant as a
straight line to another observer at a different part of the
earth; and we have shown that this appearance is due to
the geometry of the sphere.

It seems singular to find that so many writers whose
popular reputation in connection with astronomy is great
have by their remarks on this subject shown they were quite
unacquainted with what we may term the practical geometry
of the sphere, and with those elementary laws of apparent
curves and apparent straight lines in the heavens which we
have demonstrated in connection with the pole star and
pointers and the curvature of comets’ tails. This singular
neglect of so important a study must not be passed over
without some further remarks, which we bring forward for
the purpose of eliciting truth, and with the objet of
checking if possible an evil in conne¢tion with science which
seems to be spreading greatly and rapidly. This evil is,
that there are a very large number of persons who pass for
and call themselves astronomers, who consider that this
science, based as it is on observation, and regulated as it is
by geometrical laws, is to be considered solely as a subject
to be treated by physical theories, and to be explained by a
sort of dogmatic assertion or sentence, which if it contain
some such words as “‘ gravity,” “attraction,” or “repulsion,”
is supposed to be unanswerable.

When we find that even in the newspapers men write
and state that the principal object of expeditions connected
with the transit of Venus is to enable navigators to better
find their latitude and longitude at sea, we at once know
the writer to be ignorant of his subjeét. When, again, we
find critics speaking of the rate of rotation of a planet
being dependent on the laws of gravitation, we again know
them to have but little knowledge of what these laws can

514 Curved Appearance of Comets’ Tails. (October,

and cannot help us to discover. When, however, we find
that a mere jumble of words, in which terms used in
astronomy and in connection with physical science are
mixed up together and put forward in a standard work
intended for the guidance of the public as an explanation—
when they have no real meaning as regards the facts they
attempt to explain, we believe every true lover of science
will agree with us that such proceedings should not only
cease to be encouraged, but should be exposed and con-
demned.

We find also that the writers who thus attempt to explain
by verbosity that which can only be solved by sound
geometry almost invariably ignore facts. That the three
angles of a plain triangle cannot be greater than 180° is to
them of no consequence, and is to be overlooked if their
not being greater interferes with some dogmatic theory.
That these remarks are not uncalled for is, we believe, too
well known to many really candid men of science. But
that there should be no mistake on this point, we will now
give one among many examples of the fact we wish to bring
forward.

We have pointed out in this article that a comet’s tail
which coincided with the equino¢tial would appear as a
straight line or as a curve, according to the position of the
observer on earth. We also demonstrated that a comet’s
tail which passed through the pole and was of considerable
length would appear as a curve, and six hours afterwards as
a straight line. The laws shown in these two cases hold
good for the bending of comets’ tails in all other parts of
the heavens, and the apparent curvature is due to a geometrical
law and not to any physical cause.

When then we find in a work of no less importance than
the ‘‘ Encyclopedia Britannica,” under the article Astronomy,
page 78, the following profound nonsense, put forward as an
explanation of an effect due as we have demonstrated to a
geometrical cause, it is evident how widely spread is this
vicious system of explanation and how hollow and unsound
are the scientific principles of those individuals who by
such verbiage delude the ignorant and impose on the half
scientific.

The following is the explanation given:—‘‘ The slight
curvature which is generally observed (in a comet’s tail) may
be accounted for by combining the motion given to the
vapours by the impulsion of the sun’s rays with the motion
of the comet in its orbit; for the detached vapours are
driven by the impact of the luminous particles beyond the

1874.] Curved Appearance of Comets’ Tails. 515

sphere of the comet’s “attraction, and consequently cease
to follow the direction of the nucleus.”

This explanation needs no further comment; it is but a
specimen of a class of so-called science which is in the
present day very extensively followed. Just as a savage
who has once seen an ele¢tric telegraph will hope to explain
everything from the effervescence of champagne to the moving
of a locomotive by attributing theseZeffects to electricity, so
his mental type in England endeavour to explain each
astronomical effeét by attributing it to the laws of
gravitation, to ‘“‘impulsion,” ‘‘ attraction,” &c., causes
which, as in the present case, have often nothing whatever
to do with the question under consideration.

Other important problems connected with astronomy are
dependent on these same geometrical laws, and will be
treated of at another opportunity.

( 516 ) (October,

NOTICES: OF > BOO Rez

The History of Music. Vol. 1. From the Earliest Records to
the Fall of the Roman Empire. By W. CuHappe ti, F.S.A.
London: Simpkin and Marshall. 1874.

Or the arts of the Ancients—of sculpture, painting, music—
sculpture is best known to us; the others are almost unknown.
A few late frescoes, a few late hymns to gods and goddesses,—
these are all that we can place side by side with the grand
sculptures of Pheidias and Myron, with those wonderful archi-
tectural works the Propylea and the Parthenon, the very ruins
of which impress us with wonder, and show how perfectly the
harmonies of the eye were understood twenty-two centuries ago.
But the poetical and dramatic art of the most cultivated of
ancient nations has also been presented to us; in that marvel-
lous trio, AZschylus, Sophocles, Euripides, we behold a combi-
nation or concentration of the purest and most perfect art. We
know how the gods were addressed, how their mysteries were
celebrated, how Antigone lamented, and how Edipus passed
suddenly and silently from the eyes of men when the dread voice
at Colonos cried ‘‘ Come hither, come.”’ But we know not how
the players played, and the choruses sang at divine celebrations,
or when the crocus-coloured peplos was carried to the summit
of the Acropolis amidst the rejoicing of the people, and the
rhythmic dances of maidens with golden grasshoppers in their
hair.

We may, however, congratulate ourselves that we have in the
work before us all that is known of Greek music, and much that
has not been known before,—a Greek hymn to Nemesis harmo-
nised by Macfarren, an explanation of Greek notation, Greek
scales, and Greek singing; of Harmonici and Kanonici.

Histories of ancient music are not common, although, so long
ago as 1581, Vincenzo Galilei published his ‘ Dialogo della
Musica Antica.” The works best known to us in this country
are those of Sir John Hawkins (1776) and Dr. Burney
(1776—1789). The work of the former was cumbrous and un-
readable, and met with but little favour, while Dr. Burney
unfortunately relied to a great extent on Boethius for his know-
ledge of ancient music. But the treatise of Boethius was a
broken reed, for its author utterly misunderstood Greek music,
and concluded that the words nete and hypate (signifying
respectively the shortest and the longest string of the seven-
stringed lyre) referred to the top and bottom of the scale; thus
he turned the Greek scale upside down. Yet the work of
Boethius, ‘De Institutione Musica,” was the text-book during

=

1874.] Notices of Books. 517

the earlier Middle Ages, and till the time of Guido d’Arezzo, in
the eleventh century.

The Greeks acquired their music from the Egyptians;
Renaissant Europe acquired its music from Greek sources.
““No Roman of antiquity,” says Mr. Chappell, “is known to
have made, or even to have attempted, any improvement in the
science of music. The Romans received the diatonic scale, of
tones and semitones, from the Greeks, at a time when it existed
only in its primitive and imperfect form. Nevertheless they
were content to retain it so, and did not follow the Greeks in
any subsequent imprevement. It is for that reason Greek music
cannot be effectually learnt from Roman writers.” In the fourth
century the practice of singing alternate verses of psalms by a
choir was introduced from Antioch, and this was called anti-
phonal. ‘The introduction of Greek words in ecclesiastical
music was another cause of confusion in the study of Greek
music; for the meaning of anti, as applied to Greek music, is
in the sense of with or accompanying, not against, and Greek
antiphons were harmonious and concordant sounds, an octave
apart. Again, according to Mr. Chappell, the Greek Harmonia
means a ‘“‘system of music,” or simply ‘‘music,” and has
nothing to do with the modern word ‘‘harmony,” either in its
English, French, German, or Spanish sense. Also, the Greek
Melodia does not mean melody according to our sense of the
word. ‘Greek Melos had not necessarily any tune in it. It
applied to the rising and falling sounds of the voice when linked
together in speech, or in rhythm, as well as in music; so that
recitation, without any musical intervals in it, would still be
melodia. Thirdly, Harmonike does not mean harmonic or
harmonics, but is a synonyme for harmonia. Again, Sumphonia
does not mean ‘symphony.’ The last expresses our ‘harmony,’
viz., concords of notes of different pitch.” No wonder that
Greek music has puzzled so many modern writers ; no wonder
Dr. Burney calls it ‘‘a dark and difficult subject, which has
foiled the most learned men of the two or three last centuries.”

Our present musical scale is founded upon that of the Greeks;
it is simply a re-adjustment of the Pythagorean scale, made in
the second century a.p., by Claudius Ptolemy, the mathema-
tician. The Greeks trace the origin of their music to Hermes,
who invented the lyre. The old Homeric lyre was an instrument
of four strings, and several accounts are given of its invention
by Apollodorus, Diodorus Siculus, and others. According to a
hymn to Hermes, of considerable antiquity, the god ‘‘ found a
mountain tortoise grazing near his grotto on Mount Kyllene.
He disembowelled it, took its shell, and out of the back of the
shell he formed the lyre. He cut two stalks of reed of equal
length, and, boring the shell, he employed them as arms or sides
to the lyre. He stretched the skin of an ox over the shell. It
was perhaps the inner skin, to cover the open part, and thus to

VOL. IV. (N.S.) 3U

518 Notices of Books. ‘October,

give it a sort of leather or parchment front. Then he tied cross-
bars of reed to the arms, and attached seven strings of sheep-
gut to the cross-bars. After that he tried the strings with a
plectrum.”’ According to another account, the lyre was invented
by the Egyptian god Thoth, who, while walking along the shores
of the Nile, happened to strike his foot against the shell of a
dead tortoise, containing nothing within its shell but the dried
cartilages of the animal. He was so pleased with the sounds
produced that he constructed a musical instrument from the
same shell, and put strings to it of dried animal sinews. It was
with the lyre of Hermes that Orpheus charmed Creation, and
even tamed the furies of Hades.

The earliest representations of musical instruments and of
concerts are to be found among the frescoes and papyri-paintings
of ancient Egypt. No less than thirteen different musical in-
struments have been noticed in various papyri:—Harp, lyre,
lute, flute, double pipes, sistrum, &c. A conductor is often seen
beating time with his hands; sometimes one conductor for
the instruments, another for the chorus. Some of these repre-
sentations go back as far as the time of Moses. ‘‘We may trace
the prototype of every Greek instrument in Egypt. No kind of
advance upon the music of that ancient country seems to have been
made till the three Alexandrian mathematicians, Eratosthenes,
Didymus, and Claudius Ptolemy, appeared successively upon the
scene, andimproved the scale. Eratosthenes, the first of them, was
born about 276 B.c. He was director of the Alexandrian
Library.”

Pythagoras is believed to have imported the octave system
from Egypt into Greece. We all know the old story of his
having discovered it: when passing a blacksmith’s shop he
heard the consonances of the fourth, fifth, and octave, and
weighed the hammers. The other story of the strings is less
trite, but equally untrue. It is said that Pythagoras took strings
of equal thickness and length, fixed them at one end, passed
them over a bridge, and weighted them at the other end with
weights of 6, 8, 9, and 12 pounds. But Galileo pointed out that
in order to get the octave, the fourth, and the fifth, from such an
arrangement, it would be necessary that the weights should be
the squares of 6, 8, 9, 12. The doctrine of the Harmony of the
Spheres was based upon the octave system of music. The ear-
liest extant notice of this system is found in some fragments
attributed to Philolaos, who was the first to make known many
of the doctrines of Pythagoras.

Greek singing, according to Mr. Chappell, must often have
severely strained the voice. In the ‘‘manly and severe ” Dorian
scale the key-note was the tenor d in the space below the treble
clef. Aristotle says that few persons could sing the voor ‘opprot,
addressed to Apollo, on account of their high notes. ‘‘ Apollo
seems to have been addressed as if he had been troubled with

1874.! Notices of Books. 519

deafness, or was supposed to be a long way off; and perhaps
that was the general style of Greek antiquity. It recalls Elijah’s
mockery of the priests of Baal—telling them to ‘cry aloud:
peradventure he sleepeth, and must be awakened.’” But for
ordinary purposes the Greek compass was much the same as
that of the present day. The various Greek octaves were called
Lydian, Phrygian, Dorian, &c., by Euclid, Gaudentius, and
other writers.

Any time during the last two centuries the question whether
the Greeks practised simultaneous consonances mixed with dis-
cords (what we call harmony) has been discussed. It was
discovered that ‘Apyorvr’a does not mean simultaneous concordant
sounds: ovpgwua is the word for simultaneous consonance, but
this was generally not allowed, ‘If the enquiry had been
pursued in the only proper way, by searching for and comparing
Greek definitions of harmonia, its meaning would inevitably
have been traced to the theory and practice of music, and
identical with the later word Harmonike. Harmonia includes
poetry united with music, but not poetry alone, and so it has a
more restricted sense than Mousike. Again, the chanting of
poetry, though unregulated by musical intervals, is melodia, and
the metre of poetry brings it within the. denomination of
Mousike; but it is not harmonia. So that the primary transla-
tion of the word harmonia is our ‘ music.’”” Mr. Chappell quotes
various ancient authors to prove that harmony was well known
to and employed by the Greeks. He quotes, among other
authors, Seneca and Cicero: the former says—‘‘ And now to
music: you teach how voices high and low make harmony to-
gether, how concord may arise from strings of varying sounds.”
(Is not this rather a free translation Mr. Chappell? ‘‘ Doces me
quomodo inter se acute et graves voces consonent, quomodo
nervorum disparum reddentium sonum fiat concordia.”) ‘Teach
rather how my mind can be in concord with itself, and my
thoughts be free from discord.” Cicero, in the second book of
the ‘“‘ Republic,” says—‘ For as in strings or pipes, or in vocal
music, a certain consonance is to be maintained out of different
sounds, which, if changed or made discrepant, educated ears
cannot endure; and as this consonance, arising from the control
of dissimilar voices, is yet proved to be concordant and agreeing,
—so, out of the highest, the lowest, the middle, and the inter-
mediate orders of men, as in sounds, the State becomes of accord
through the controlled relation, and by the agreement of dissi-
milar ranks; and that which, in music, is by musicians called
harmony, the same is concord in a State.” Mr. Chappell consi-
ders that Cicero’s mere definition of the word concentus, and the
assertion of Aristotle that ‘‘all concordant sounds are more -
agreeable than single notes, and of concords the octave is the
most agreeable,” are alone sufficient to prove that the Greeks
were acquainted with harmony. ‘ But,” he adds very happily,

520 Notices of Books. [O¢tober,

‘‘ floating upon the surface of music has been for ages more
popular than diving.”

We come now to the eighth chapter of the ‘‘ History,” which
is important, inasmuch as it contains three Greek hymns, written
out in accordance with our modern notation, and supposed to be
the only trustworthy remains of Greek music. They were first
published by Vincenzo Galilei, the father of the astronomer, in
1581, and were copied from Greek MS. in the library of Cardinal
St. Angelo. The date of the hymns is uncertain, but it is not
considered probable that they are older than from the second to
the fourth century, A.D. The first is a hymn to Calliope, with
an accompaniment in the Hypo-Lydian mode by George Mac-
farren; the second a hymn to Apollo, both grave and solemn,
and something like some of the graver hymns of the Catholic
Church; the third, a hymn to Nemesis, is by far the most
striking of the three, and contains a very definite and distinctive
theme.

A curious example of the delicacy of the human ear is to be
found in the fact that the so-called ‘‘Comma of Didymus,” the
interval between a major and a minor tone, or between the 80th
and 81st part of a vibrating string, sufficed to produce the great
change between the scale of Pythagoras and the scale which we
now use. The harmonic scale was developed during the last
century ; it was discovered in 1673, by William Noble, of Merton
College, and Thomas Pigot, of Wadham. It is the scale of
natural sounds arising from the successive aliquot divisions of a
string, and, according to Mr. Chappell, it forms the basis of the
science of music.

The last four chapters of Mr. Chappell’s book are devated to
an account of the musical instruments of the ancients :—Various
kinds of pipes, and the way in which they were sounded, and
the materials of which they were made—lotus, laurel, palm-
wood, pine-wood, box-wood, beech-wood, elder-wood, ivory,
reeds of various kinds, leg-bones of animals and of large birds
(such as the eagle, vulture, and kite). Then there were pipes
receiving their name from the country in which they were in-
vented—as Alexandrian, Tuscan, Theban, Scythian, Phoenician,
Lybian, Arabian, Phrygian. The Theban pipes were made of
the thigh-bones of a fawn, and were covered with metal. ‘The
length of Arabian pipes was proverbial, and a man of whose
tongue there seemed to be no end was called an Arabian piper.”
The ‘sweet monaulos”’ was for weddings, and the Phrygian
pipes were ‘‘for wailing and lamenting.” After wind instru-
ments come instruments of percussion, such as the drum,
dulcimer, timbrel, sistrum, cymbals, and krotala. According to
Mr. Chappell the sistrum was simply shaken, so as to produce a
jingling sound; Plutarch has given a long account of the instru-
ment. The Assyrians appear to have had a sistrum of a different
form, which was struck by a rod of metal serving as a plectrum.

1874.] Notices of Books. 521

The Greeks appear to have possessed three kinds of cymbals. As
for stringed instruments, their number was considerable: there
were many kinds of lyre, harps, psalteries, four-stringed trigons,
and guitar-like instruments. The largest kind of lyre had many
strings, and was placed upon a stand; the others were carried in
the hand. Athenzus quotes a singular story told by Artemon,
to the effect ‘‘that Pythagoras once strung the three sides of a
Delphian tripod, such as was used to support an ornamental
vase, and that he tuned one side to the Dorian scale, another to
the Phrygian, and the third to the Lydian scale or mode. So
far all was possible, but it is improbable that Pythagoras should
have attempted it, because there could be no tone from such a
tripod, for it had no sounding-board. The minuteness of the
remaining part of the story proves the whole to be a myth.
Artemon adds that Pythagoras contrived a pedal to turn this
tripod, and that he twisted it about with such rapidity while he
was playing that any one might have fancied he was hearing
three players upon three different instruments.”

Mr. Chappell considers the Greeks to have been very unin-
ventive in regard to musical instruments, which all seem to be
Asiatic or Egyptian. The lyre is found in Egyptian paintings
before the Greeks existed as a nation. ‘*We can find no new
principle for stringed instruments discovered by a Greek, nor
anything new in pipes. All was ready-made for them, together
with their system of music. The Greeks were even inapt
pupils; for, although they had many strings ever before their
eyes, they did but reduce the number, after a time, to bring the
instruments down to their own level. They practised a certain
amount of harmony, but not so much as earlier nations.” Our
author even goes so far as to compare Greek music of an early
date with modern Japanese music, of which a curious account is
given on p. 304. We are glad to notice representations
(pp. 314—315) of the beautiful harps from the tomb of Rameses
the Third.

The thirteenth and final chapter of the work is devoted to
organs, and Mr. Chappell has carefully investigated the various
forms of hydraulic and other organs described by Hero in hig
IIvevparuwa. He has even had a model of one of them constructed,
and points out its advantages. The invention of the hydraulic
organ is attributed to Ctesibius, who appears to have lived about
284 B.c. The precise meaning of the word opyavoy has some-
times led to confusion. It was often used to mean any instru-
ment ; it might be a surgical instrument, or a musical instrument,
or an organ of sense,—as the instrument of reasoning,—and so
on. The first description of the hydraulic organ is given by
Hero of Alexandria, who was a pupil of Ctesibius. A second
full account of it is given by Vitruvius, in his Treatise on
Architecture, written between B.c. 20 and 11. Many of the
early editions of the ‘‘ Pneumatics” appeared with drawings,

522 Notices of Books. [October,

but none of these are said to be older than the fourteenth or
fifteenth century. A capital drawing of the organ is given on
p- 340. It had keys, pipes, valves, a wind-chest, and a pump
for condensing air into the wind-chest, and even stops. The
Romans, in the time of Nero, appear to have had organ-
contests, and medals were given as prizes, one of which is in
the British Museum.

Mr. Chappell’s work is altogether interesting, and contains a
good deal of new matter. A few of the chapters appear to be
unnecessarily complex, and perhaps can be somewhat simplified
in a second edition. A few errors exist, which may also then be
altered: perhaps the most important of these is to be found in
the foot-note to p. 187-188,in which Lissajous’ Figuresare wrongly
described as produced by sand on vibrating plates. The book is
well printed and illustrated, and we shall look forward with
interest to the appearance of the remaining volumes.

The Harveian Oration for 1874. By CuarLtes West, M.D.,
F.R.C.P. London: Longmans, Green, and Co. 1874.

THE practice of giving the annual Harveian Oration in Latin
has been discontinued for several years; and in this country it
is not easy to hear a Latin address, save on certain occasions
in our older Universities. In Leyden, and in some of the
German and Italian Universities, it is, however, a far commoner
practice. The present oration could well be converted into
somewhat florid and verbose Latin: for example, think of such
resounding periods as the following :—‘‘ When your commands,
Sir, were first laid upon me to undertake this most honourable,
most arduous office, I studied, as a preparation for its accom-
plishment, all the Harveian orations that I could meet with.”
Or, again—‘‘ Such was the man, such were his pursuits; loving
knowledge for its own sake; loving it, too, not in pride of intel-
lect,” &c. The oration relates to the Life and Times of Harvey.
It tells us that he was born in 1578, that he left school and
entered at Caius College at the age of 15, and took his B.A. in
’ 1597. On leaving Cambridge he went to Padua, then a most
celebrated University and Medical School. At one time it pos-
sessed no less than 18,000 students, and it numbered among its
Professors some of the most eminent men in Europe. Harvey
passed nearly five years at Padua, and took his degree in 1602; ©
on returning to England, he became M.D. of Cambridge in
1603, F.R.C.P. in 1607, married and commenced practice in
London, and in 1609 became Physician to St. Bartholomew’s
Hospital, and then he worked hard at anatomical discoveries.
His greatest discovery is described by Dr. West as follows :—
‘First. After corroborating the statements of those who had

1874.] Notices of Books. 523

denied either that blood transudes through the walls of the ven-
tricles, or that the pulmonary veins bring back to the left side of
the heart air commingled with the blood, he asserts that the left
ventricle has no other function than that of impelling the blood
brought to it through the arteries, which themselves contain
blood and nothing else, not air, nor vital spirit, but blood purified
by its passage through the lungs, and so made apt for the
nourishment of the whole body. And second. That while the
arteries thus distribute everywhere the fresh pure blood, the
veins with which they communicate bring back that same blood,
no longer pure, to the right side of the heart, whence it is once
more transmitted to the lungs, thence carried again revivified to
the left ventricle, and then once more distributed throughout the
body, its changes not being those of an ebbing and a flowing
tide, but the ceaseless current of an onward rushing river.”
The doctrine of the circulation of the blood was taught as early
as 1615 by Harvey, but it was not till the year 1628 that he pub-
lished his ‘‘ Exercitatio de Motu Cordis.” The conclusion of the
oration is devoted to a somewhat graceful allusion to benefactors
of the College :—‘‘ Benefactors—those who have done us good,
or have shown us kindness; in vulgar sort, those to whom we owe
gifts of money, grants of land, something or other that can be
bought or sold in open market. According to this reading, few
indeed have been our benefactors.”’ All the money properties of
the College do not exceed £600 a year, and the plate not more
than £20. The College, says Dr. West, will bear no comparison
with the magnificent Halls of the City Companies; and then
later on he says—‘‘ Our great benefactors are they who have left
us the inheritance of their example.” Such as Sydenham, and
Meade, Jenner, and Bright, and pre-eminently Harvey.

Divine Revelation, or Pseudo-Science? An Essay. By R. G.
SucKLING Brown, B.D. London: Longmans, Green, and
Co. 1874.

Tuis is one of the many anti-Darwinian books, which the author
calls ‘‘our form of resisting the hypothesis of evolution, and
kindred pseudo-sciences.” We fear we must pronounce Mr.
Brown’s book to be illogical and unscientific, and of little value
even to the opponents of the Darwinian theory. We give the
concluding lines, and so leave the book to the judgment of the
reader :—‘‘ The admirable adaptation of the bird’s wing; the
contrivance of the human fore-arm, hand, and foot ; the poise of
suns and planets in infinite space: their accelerated and dimi-
nished velocities in the ratio of their distance from their centres
of attraction or gravitation; the apparatus of the infusorial
Rotifer, the tyrant over the inhabitants of a drop of water; the
delivery of its contemplated victim by its provided apparatus for

524 Notices of Books. (October,

withstanding the torrent, stirred by its tyrant’s paddles; all these
great, minute, and wondrous; all these most curious and ad-
mirable works of an Almighty Designer and Creator, who
governs by compensation, and tempers compensation by insti-
tuting a maximum of enjoyment through a minimum of
suffering; who maintains His creations by the law of self-
preservation: all these, and multitudes of other benignant fore-
thoughts, these busy physiologists overlook, neither thinking,
nor asking, nor, they give us reason to imagine, caring to know
‘Whose works are these?’ Nay, more! while they are loqua-
cious of acids and salines, they forget to think out or to ask
‘Whose works are these?’ Who made acids and salines ?
And while they trace ‘the human animal,’ for such they account
man to be, and such they would make him, to the askidion or
the monad, they consider not, and forget to ask, ‘ Who made the
monad and the askidion ?’”

The Correlation of Physical Forces. Sixth Edition. With other
Contributions to Science. By the Hon. Sir W. R. Grove,
M.A., F.R.S., one of the Judges of the Court of Common
Pleas. London: Longmans, Green, and Co. 1874.

WE are very glad to welcome a sixth and revised edition of Sir
W. Grove’s celebrated Essay. By “revised” we mean simply
that those discoveries in Science which bear upon the subject of
the relationship of the physical forces made since the first ap-
pearance of the Essay, in 1843, have been added, and the whole
has been thus rendered more complete. It may be said that the
Essay has done its work, that scientific men fully realise the
correlation of the physical forces, which has been so wonderfully
exemplified during the last thirty years by the science of thermo-
dynamics, but the Essay still remains a model of accurate rea-
soning, and of an elegant scholarly style, and will always be
studied with advantage by the student of Science. We need
not give a very detailed account of its object; it is too well
known to require that. But, in brief, the design is to show that
if we take the so-called physical forces,—motion, light, heat,
electricity, magnetism, and chemical affinity,—each one is
capable of producing the remaining five ; and, further, from first
to last the author combats the idea of such hypothetical entities
as ethers, subtle fluids, &c., which have been devised to account
for phenomena otherwise not easily explained. He endeavours
to show that each and allof the physical forces is an affection of
matter, not matter itself,—that, in fact, it is a mode of motion;
and this idea, now fully admitted in the case of heat and light,
will, no doubt, in our generation be extended to electricity and
magnetism.

Without giving any very connected chain of reasoning in a

1874.] Notices of Books. 525

book which has long been before the public, we will indicate here
those passages which are striking from their originality or pre-
cision, or from some other cause. As to causation, our author
remarks that the view entertained of it is usually that of Hume,
who refers it to ‘invariable antecedence,” a cause being that
which invariably precedes, and in effect that which invariably
succeeds; and he shows that this definition will not bear strict
scrutiny. As to the aims of physical science, he remarks—
“Instead of regarding the proper object of physical science as a
search after essential causes, I believe it ought to be, and must
be, a search after facts and relations; that although the word
Cause may be used in a secondary and concrete sense, as
meaning antecedent forces, yet in an abstract sense it is totally
inapplicable.”

Form is defined as “that active principle inseparable from
matter which is supposed to induce its various changes,’—not,
to our mind, a satisfactory definition, although we know not
where to look for better. Referring to “force in abeyance,” or
tension, or what we should now call ‘ potential energy,” Sir W.
Grove gives us the following comprehensive and perfectly logical
remarks :—‘‘ But it may be objected, if tension or static force be
thus motion in abeyance, there is at all times a large amount of
dynamical action subtracted from the universe. Every stone
raised and left upon a hill, every spring that is bent and has re-
quired force to upraise and bend it, has for a time, and possibly
for ever, withdrawn this force, and annihilated it. Not so; when
we raise a weight and leave it at the point to which it has been
elevated, we have changed the centre of gravity of the earth,
and consequently the earth’s position with reference to the sun,
planets, and stars; the effort we have made pervades and shakes
the universe; nor can we present to the mind any exercise of
force which is not thus permanent in its dynamical effects. If,
instead of one weight being raised, we raise two weights, each
placed at points of the earth diametrically opposite to each other,
it would be said, here we have compensation, a balance, no
change in the centre of gravity of the earth; but we have in-
creased the mean diameter of the earth, and a perturbation of
our planet, and of all other celestial bodies, necessarily ensues.”

The definition of heat as ‘“‘a communicable molecular repulsive
force”? would scarcely be very generally accepted, we think. A
repulsive force cannot readily be defined, or in the abstract be
conceived ; but if we regard heat as vibratory motion, we can at
once realise how expansions are produced by the addition of such
motion to congeries of molecules, which vibratory motion will
of necessity drive them further apart.

Of electricity, Sir W. Grove says—‘“I think I shall not be un-
supported by many who have attentively studied electrical
phenomena, in viewing them as resulting not from the action of
a fluid or fluids, but as a molecular polarisation of ordinary

VOL. IV. (N.S.) ax

526 Notices of Books. ‘October,

matter, or as matter acting by attraction and repulsion in a
definite direction.”

The remarks to be found on pp. 106 and 107, relating to the
finite nature of our intellects, are much to be commended to the
notice of scientific men, at a time when perhaps as much as in
that of the Greek Positivists, or more modern Encyclopedists,
intellectual pride is the bane of too many otherwise great.
minds :—‘‘ Men are too apt,” remarks our author, ‘‘ because
they are men, because their existence is the one thing of all
importance to themselves, to frame schemes of the universe as
though it was formed for man alone: painted by an artist of the
Sun, a man might not represent so prominent an object of
creation as he does when represented by his own pencil.”

Sir W. Grove often leads us from a purely physical to the
verge of metaphysical discussion. In regard to the boundaries
of the universe, he says—‘‘ We cannot conceive a physical
boundary, for then immediately comes the question, What bounds
the boundary ? and to suppose the stellar universe to be bounded
by infinite space, or by infinite chaos, that is to say, to suppose
a spot—for it would then become so—of matter in definite
forms, with definite forces, and probably teeming with definite
organic beings, plunged in a universe of nothing, i is to my mind,
at least, far more unphilosophical than to suppose a boundless
universe of matter existing in forms and actions more or less
analogous to those which, as far as our examination goes, per-
vades space.”

The last of the physical forces which is considered is chemical
affinity, of which it is truly observed that it is that mode of force
of which the human mind has hitherto formed the least. definite
idea. We think that the weakest part of this Essay is that in

which the other'physical forces are said to produce chemical
affinity: thus we read on p. 26—‘‘In the decompositions and
compositions which the terminal points proceeding from the
conductors of an electrical machine develope when immersed in
different chemical media, we get the production of chemical
affinity by electricity, of which motion is the initial source.”
Again, light may effect chemical combinations and decomposi-
tions, but it does not produce chemical affinity as a force; it
simply determines a chemical change, or determines a mani-
festation of chemical force, which had all along been existent in
the bodies which undergo the change. We find, among the con-
cluding remarks, a statement of instances in which some one
force being disturbed, all the others appear:—‘‘ Thus, when a
substance, such as sulphuret of antimony, is electrified, at the
instant of electrisation it becomes magnetic in directing at right
angles to the lines of electric force ; at the same time it becomes
heated to an extent greater or less, according to the intensity of
the electric force. If this intensity be exalted to a certain point
the sulphuret becomes luminous, or light is produced: it expands

1874.] Notices of Books. 527

consequently, motion is produced, and it is decomposed, there-
fore chemical action is produced.” ‘This is a kind of tutti, after
each one has been singing his solo.

Few words are used more loosely and indefinitely than the
word Nature; it is sometimes called ‘the principle which pro-
duces all things;”’’ hence, poetically, the ‘* Universal Mother,”
** Madre Natura,” &c. We remember to have read, in one of the
older numbers of the ‘ Philosophical Transactions,”—‘ By
Nature I understand the works of God manifested in Creation ;”
then we talk about the “laws of Nature,” the “works of
Nature,” &c. Sir W. Grove says (p. 152)—‘‘ The word ‘ Nature’
is still more personified; instead of being used to denote, what
alone it can denote,—namely, things as we see, hear, or feel
them, and their relations ascertained by comparison and abstrac-
tion,—Nature is treated as a sort of Superintending Angel, who
enjoins this, permits that, and forbids the other.” Finally, as to
matter and force, he says—‘‘ The evidence we acquire of the
continued existence of matter is by the continued exertion of the
force it exercises, as, when we weigh it, our evidence of force
is the matter it acts upon. Thus matter and force are correlates
in the strictest sense of the word; the conception of the existence
of the one involves the conception of the existence of the other:
the quantity of matter, again, and the degree of force, involve
conceptions of space and time.”

The Address ‘‘On Continuity,” which has already reached a
third edition, was delivered by Sir W. Grove, as President of the
British Association, at Nottingham, in 1866. It is, to our mind,
quite a model of what a President’s Address should be. Not a
vehicle for the exclusive advocacy of Darwinism and free thought,
but a resumé of the whole aspect of Science at that particular
time, and an allusion to all the more dominant phases of thought
which then prevail, and to the more prominent discoveries and
generalisations. ‘These are interspersed with his own far-seeing
and luciferous ideas :—-‘‘ As Phlogiston,” he says, ‘‘and similar
creations of the mind have passed away, so with hypothetic
fluids, imponderable matters, specific ethers, and other inventions
of entities, made to vary according to the requirements of the
theorist, I believe the day is approaching when these will be dis-
pensed with, and when the two fundamental conceptions of
matter and motion will be found sufficient to explain physical
phenomena.”

The remainder of the work (that is to say, half of it) contains
Sir W. Grove’s researches in experimental science. Commencing
with the nitric acid battery, now so well known and so much
used, and which was devised in 1839, we find, in succession, the
gas battery, the decomposition of water by heat, the striz in the
electrical discharge, and the effects of heat on fluids. There are
many other papers, all containing a good deal of suggestive
matter, and hints as to new researches.

525 Notices of Books. (October,

We know of no book, save the admirable ‘‘ Experimental
Researches” and ‘‘ Chemical Manipulation” of Faraday, which
we could more recommend, both to the general reader of Science
and to the young student, than this: clear and elegant in style,
powerful in grasp, close and precise in reasoning, eminently
suggestive, and very comprehensive, the book will continue to
be a standard scientific work, and will always find a welcome
place among the archives of the History of Scientific Ideas.

The Universe and the Coming Transits. Presenting Researches
into, and New Views respecting, the Constitution of the
Heavens; together with an Investigation of the Conditions
of the Coming Transits of Venus. Recently confirmed by
a Unanimous Vote of the Chief Astronomers of Great
Britain. By Ricuarp A. Proctor, B.A. (Camb.). London:
Longmans, Green, and Co. 1874.

Mr. Procror is certainly the most prolific scientific writer of the
age; he is a very Lope de Vega among scientists: book after
book appears from his pen; his thoughts fly out as the sparks
fly upwards. Sun, moon, and stars have alike received detail
treatment at his hands; and here we have a new theory of the
universe, and a collection of all the matter relating to the transit
of Venus which he has published in the ‘Journal of the Royal
Astronomical Society,” and elsewhere. The book, in common
with all his works, is very profusely illustrated ; maps, charts,
plans, woodcuts, are scattered throughout the volume,—for Mr.
Proctor is a good draughtsman as well as a learned astronomer.

The first Essay, ‘‘ On Star-Streams,” treats of the Milky Way,
which is now believed to consist of myriads of suns, around
which no doubt there are attendant planets, which latter may
contain countless numbers of living creatures. A very interesting
account is given of the changes in the appearance and position
of the Milky Way at the same hour, in different seasons of the
year. By a simple illustration of the appearance that the lights
of a large town would present to anyone looking from a height,
we are shown that we must not necessarily suppose that the
brilliancy of a star is positive evidence of proximity, but rather
must bear in mind that we are dealing with a sphere full of stars,
distributed through space, some at much greater distances from
us than others, and not with a spherical surface covered with
stars, as represented by a globe or map. For aught we know
the whole stellar region may be occupied, more or less richly, by
a variety of forms of matter other than stars or suns, and
nothing but the most patient and systematic analysis can ever
lead to the solution of the great problem of star-depths.

The article entitled ““A New Theory of the Universe” is at

1874.] Notices of Books. 529

once the longest and the most interesting contained in the
volume: it was originally brought out in ‘The Student” for
February, March, and April, 1869; therefore many discoveries
and some extensions of the subject have been made since, but
this in no way interferes with the correctness of the paper.
Mr. Proctor begins by a comparison of what was known of the
solar system at the end of the last century with what is known
at the present time: first among the remarkable discoveries
made within the last sixty years must be noticed the great
increase in the number of primary attendants upon the sun;
the g8th asteroid was just discovered at the time this Essay was
written, and yet it was but on the opening day of the present
century that the first of these bodies was brought to light. The
mind gets bewildered in imagining all these bodies, primaries of
the planetary system, revolving in paths closely interwoven, the
more so when—given these constant additions to the numbers
known—we may fairly assume that for each discovered asteroid
there are to be reckoned tens, perhaps hundreds, which will
never be found out. Then the myriads of dependent comets
that are found to exist within the solar system, revolving round
the great centre in the most eccentric orbits, must still remain
among the mysteries of Science. At the present time, when the
minds of even the most unscientific among us have been more
or less interested by the appearance of a comet, this branch of
the subject presents a special attraction, and it is most ably
treated. A still more remarkable feature of modern astronomical
discovery remains to be noticed; that is, that meteors, shooting
stars, and aérolites, which have always been regarded as meteor-
ological phenomena, must now be placed among the attendants
of the sun. It is beyond doubt that the earth encounters
fifty-six systems at least of these small bodies, and ‘‘ What is
the likelihood,” asks Mr, Proctor, ‘‘that if there were only a few
hundreds of such systems the earth would encounter so manyas
fifty-six?’ ‘The extreme probability, nay certainty, is that such
systems may be reckoned not by hundreds and thousands, there-
fore, but by millions of millions. A close connection, if not
identity, can be traced between comets and shooting star sys-
tems, as it is discovered that at least two of the meteoric systems
coincide with the orbits of known comets. The Sidereal System
next engages the attention, and the last twenty pages of this
Essay are devoted to the consideration of what our astronomer
terms ‘“‘those mysteries of mysteries,’ the nebula. The entire
paper deserves careful and attentive study.

The next article, bearing the title “‘ What Fills the Star
Depths?” is almost entirely devoted to mathematical problems
proving that the arrangements of stars in different regions, &c.,
is not the result of accident, but rather that some real laws of
aggregation exist among the stars. And then we come to an
Essay of great interest, headed “ Star-Drift,” and treating—as

530 Notices of Books. [Otober,

the name implies—of stellar motion, particularly of the motion
of the “sun, with his whole cortege of planets and cometary
systems sweeping swiftly throughspace.” Thisstar-drift, however,
must not be confounded with the phenomenon of drift as applied
to Ursa Major and other constellations, and treated of in another
part of the same paper. The star-drift due to the sun’s motion
in space may be called general, and has altogether a different
significance to the other star-drift, which is only local. The one
takes place in almost exactly the reverse direction from the other,
and is perfectly distinct. In this chapter Mr. Proctor more than
redeems a little self-assertion observable elsewhere, by his
cordial expressions of admiration of the labours of his great
countrymen, the Herschels.

The following Essays, ‘‘ Are there any Fixed Stars ?” “* News
from the Stars,” ‘“‘On two Rich Nebular Regions,” &c., are re-
printed from various sources, and discuss the most recent
problems in Astronomy. The Essay ‘On the Construction of
the Heavens,” containing Jean Paul’s wonderful dream of the
universe, appeared in this Journal in July, 1872.

The second part of the volume—about one-third—treats ex-
clusively of the coming transits of Venus, and is more technical,
and consequently less popularly interesting, than the former
portion of the work. The first transit will take place on
December 8th of the present year; the second on December 6th,
1882 ; and both have such important bearing upon the problem of
the sun’s distance that men of science are anxiously looking
forward to the times of their occurrence. After the present
century no like phenomenon will occur until the year 2004; and
in one respect the transit now at hand will present even better
opportunity for making important calculations than that of 1882,
so that foranumber of years astronomers will be without the means
of remedying any omissions now made: it is this consideration
that induces Mr. Proctor to appeal most earnestly to his country
to send out expeditions suitably furnished for making the most
effective observations for the determination of the sun’s distance:
he feels that the scientific honour of his country is at stake, and
most clearly and ably shows the manner in which it may be
saved. There seem to be difficulties in the way of carrying out
many of these observations, but it is greatly to be desired that
the subject will meet with the recognition it deserves: any
omission in making the proper arrangements for this important
work might be obviated by due attention to the details so clearly
set forth by Mr. Proctor; and we cannot close his book without
a feeling of admiration for the manner in which he has thought
well to bring his researches thus before the public, and for his
perseverance and industry.

1874.] Notices of Books. 531

Handbook of Natural Philosophy. By, Dionystus LARDNER,
D.C.L. Hydrostatics and Pneumatics. Edited and the
greater part re-written by Benjamin Loewy, F.R.A.S.
London: Lockwood and Co.

In sciences like Hydrostatics and Pneumatics, on whose facts
there is little, if any, variety of opinion, and which have been
undisturbed by any recent revolution in theory, or even in no-
menclature, the compilation of handbooks is comparatively
simple, and there is accordingly very little scope for criticism.
The work before us is well arranged and clearly written, and may
be recommended to all who require a knowledge of the subjects
treated of without having the time or the inclination to enter
upon mathematical refinements. Purists in methodology might,
perhaps, raise the question whether the consideration of the
diffusion of liquids, of the division of soluble bodies into crys-
talloids and colloids, and of the phenomena of osmose, can be
legitimately introduced into a treatise on hydrostatics, involving,
as they do, chemical principles.

Platiner’s Manual of Qualitative and Quantitative Analysis with
the Blowpipe. Revised and enlarged by Prof. To. RicuTer.
Translated by H. B. Cornwa t, assisted by J. H. CASwELL.
Second Edition, revised. New York: D. Van Nostrand.

Pror. PLATTNER is generally recognised as facile princeps
among authorities on blowpipe analysis, and his great work has
passed beyond the domain of criticism. Of all the editions
which have appeared in the English language, the present must
claim the palm. It is founded upon the most recent German
edition, as enlarged and revised in accord with the latest disco-
veries by Prof. Richter, of the Freyberg Mining School, the
worthy pupil of Plattner. The translation has been carefully
and judiciously executed. We are happy to say that there has
been no attempt at abridgment, a thing impracticable without
sacrificing that thoroughness which was a characteristic of
Prof. Plattner, and on which the main value of his work
depends.

We hope that this edition may be duly appreciated, and con-
sider that it cannot fail to lead to a wider knowledge of the
utility and the resources of the blowpipe.

Theory of Arches. By Prof. W. Attan. New York: D. Van
Nostrand.

Tuis work forms one of the **‘ Science Series” of the eminent
publisher by whom it is issued. It is an expansion of the views

532 Notices of Books. (October,

of the late Prof. Rankine upon this subject. The writer develops
the theory of arches by beginning with a consideration of forces
acting upon a suspended chain or cord. We have no doubt that
it will prove of great value to architects and engineers.

Geology. By T. G. Bonney, M.A., F.G.S. London: Society
for Promoting Christian Knowledge.

Tue author of this little treatise has, as he tells us in the Preface,
‘‘attempted to set down briefly the principal facts of Geology,
and the conclusions which have been drawn from them ; to indi-
cate the nature of the earth’s crust, the processes which have
acted and are still acting upon it, and the probable history of
that little portion upon which we live.” The attempt has been
by no means unsuccessful, and the result is a work well calcu-
lated, we believe, to lead to further enquiry. With the following
remark we most heartily concur:—‘‘ The great aim of the
Natural Sciences is to teach students to observe and think for
themselves: when this result is not produced they are mere
cram, and do more harm than good.”

The wondrous tale written on the rocks is told here in the
simplest possible words, and technical language, if not entirely
avoided, is kept subordinate. The author, we should say, is not
one of those men of science who would write a book merely for
the sake of displaying a “ fire-new”’ nomenclature. The very
appearance of this work, and the frank admission not only of the
incalculable age of the world we inhabit, but of the antiquity of
the human race, is an instructive sign of the times. Had such
a work been issued, under such auspices, half a century ago,
certain of our contemporaries would—if such a thing be possible
—have out-scolded and out-shrieked Louis Veuillot and Joseph
de Maistre.

We wish this book a wide circulation, and feel convinced that
it will have a good effect on the public mind.

Fourth Annual Report of the Board of Commissioners of Public
Charities of the State of Pennsylvania. Harrisburg:
B. Singerly.
Tuts report contains much interesting information on the ma-
nagement of reformatories, criminal schools, and lunatic asylums
in Pennsylvania. The treatment of pauper lunatics in some of
these establishments appears to be shocking (cxlvii.). It seems
from the “suggestions,” p. 105, that in America persons who
have been so unfortunate as to witness the commission of a crime
may be committed to prison—if unable to find security for their

1874.] Notices ef Books. 533

appearance—in order to secure their evidence at an approaching
or postponed trial. Apart from the obvious injustice of such a
system, we think it must frustrate the enforcement of the law,
by furnishing those who are in any way aware of the perpetration
of a crime with a reason for keeping silence even more potent
than the insolence and the brow-beating which witnesses, except
persons of rank and station, have to suffer from counsel in
England.

To statisticians, philanthropists, and persons interested in the
management of asylums, hospitals, gaols, and poor-houses, this
volume will prove invaluable.

Mineralogy. By Frank Ruttey, F.G.S. London: T. Murby.

Tuis work belongs to ‘‘Murby’s Science and Art Department
Series of Text-Books,” edited by B. J. Skertchly, F.G.S. What
share, if any, the last-named gentleman has had in the produc-
tion of the treatise, or to what extent he is responsible for its
contents, it does not appear. The work, as we are told in the
Preface, is destined to meet ‘“‘the requirements both of ele-
mentary and advanced students for the Science and Art Depart-
ment Examinations.” It may, perhaps, be looked upon as an
old-fashioned prejudice, but we like people to study any subject
whatever in order to know, and not in order to pass examina-
tions. We dislike cram, crammers, and crammees. We have
no sympathy for the man into whom a certain dose of science
has been forced at high pressure, like carbonic acid into a bottle
of soda-water. When the pressure is removed, the science in
the one case and the gas in the other escape with noise and
effervescence, leaving a residue stale, flat, and unprofitable.
But whilst thus taking exception to the declared object of the
work, we must speak favourably of its contents. It might prove
a difficult task to present a greater amount of useful matter in
so limited a compass. The distinctive features.to which the
author lays claim are the general arrangement of the materials,
the minerals being ‘“ grouped according to their most prominent
basic constituents, and preceded by a brief description of the
chemical and physical characters of the leading base in each
group.”

In the illustrations there is a novel feature:—The manner in
which crystals are drawn and their faces shaded is peculiar, the
shading or stippling being made to show at a glance the mutual
relation of the faces developed on compound forms. The
classification of the silicates has been made to depend on the
crystallographic systems to which they belong.

The work begins with a definition of minerals as distinguished
from organic bodies, and an explanation of the difference be-
tween mineral species and rocks, showing the respective spheres

VOL. IV. (N.S.) 3Y

534 Notices of Books. [October,

of the geologist, the mineralogist, and the chemist. We find
next a condensed account of chemical composition, of the
elements, of acids, bases, and salts, and of isomorphism. The
second chapter teaches—as far as it can be attempted in a
compass so brief—the use of the blowpipe. The physical pro-
perties of minerals form the subject of the next two chapters.
To this succeeds an account of crystallography, followed by a
systematic description of mineral species, forming the main
portion of the work. The sources and occurrence of the various
minerals are, for the most part, carefully given, though such
localities as ‘‘ Siberia,’ ‘‘ Australia,’ and ‘‘ United States,” must
be considered rather vague. Precision in this matter is of great
importance in every department of Natural History. Even in
case of widely distributed forms it is safest to state the exact
spot where they have been met with. In speaking of gold, the
author gives Tasmania and Van Dieman’s Land as two distinct
regions. English and American localities are generally placed
as far as possible apart from each other, to prevent the confusion
which the similarity of names is apt to occasion. The per-
centage amount of sulphur in iron pyrites is given as 63,—
probably a typographical error.

Principles of Mechanics. By T. M. Goopeve, M.A., Barrister-
at-Law, Lecturer on Applied Mechanics at the Royal School
of Mines. London: Longmans, Green, and Co. 1874.

As Prof. Goodeve’s ‘‘ Elements of Mechanism” has so long been
established as a standard text-book, we were prepared to receive
favourably another work by the same author on a kindred subject.
Nor are we disappointed. A glance at the present volume,
which forms one of the series of Text-Books now being issued
by Messrs. Longmans, is sufficient to show that it will help to
sustain the high character which the mechanical and physical
part of this series has already acquired.

As Lecturer at the Royal School of Mines, Prof. Goodeve
knows well how to treat his subject. The student is made, at
the outset, to realise the idea of Force, and to understand the
modes by which it may be measured. At an early stage he is
brought to grapple with some of the modern views which have
been introduced into mechanics, such as the mechanical relations
of the theory of heat. The laws of motion and the general
principles of dynamical and statical science are clearly enunci-
ated and copiously illustrated. Indeed, the characteristic feature
of the present work is the constant reference which is made
from the principles of the science to its practice. No sooner has
the author laid down a principle than he proceeds to apply it by
describing some useful examples, which exhibit its practical
application. Hence we find in this work notices of many

1874.] Notices of Books. 535

inventions which we hardly look for in an ordinary treatise on
the Principles of Mechanics. We may substantiate our state-
ment by reference to the descriptions of Giffard’s Injector,
Blake’s Stone-Crusher, the Moncrieff Gun-Carriage, Whitworth’s
Measuring Machine, and many other ingenious mechanical in-
ventions. In fact, the author constantly seeks to interest the
student by keeping the practical phase of the subject before him.
Prof. Goodeve evidently has no notion of a student learning
Mechanics by merely mastering abstract principles and acquiring
dexterity in the application of formula. If such knowledge is
to be any real service to a man, it must be supplemented by
practical knowledge, such as may be gained in the workshop.
“* Mechanics,” says Prof. Goodeve (p. 40), ‘‘cannot be learnt
from books alone. The student must go out into the world, and
see how mechanicians and engineers accomplish what they do;
he must continually reason upon what he sees, and, retaining a
firm hold of mechanical principles, he may thus gradually obtain
a knowledge and mastery of his subject.”

Elements of Metallurgy. A Practical Treatise on the Art of
Extracting Metals from their Ores. By J. ARTHUR PHILLIPS,
M. Inst. C.E., F.G.S., F.C.S., &c. Illustrated by numerous
Engravings on Wood. London: Charles Griffin and Co.
1874.
RATHER more than twenty years ago Mr. Phillips wrote an ex-
cellent ‘‘ Manual of Metallurgy,” which originally formed one of
the volumes of the ‘Encyclopedia Metropolitana.” This
manual passed through three editions, and a fourth has been
long expected. Instead, however, of publishing a new edition
of this Manual, the author has followed the far preferable course
of presenting us with an entirely independent work. It is pro-
verbially injudicious to put new wine into old bottles, and it has
too often been found that to insert a quantity of new matter into
an old text-book produces a result which is the very reverse of
satisfactory. We are therefore not sorry to see the older work
superseded by one which treats the entire subject from a modern
point of view, and which may be thoroughly relied upon for
giving its information quite up to date. Such a work was much
needed, and the need could hardly have been better supplied
than it has been by Mr. Phillips.

After a brief sketch of the history of Metallurgy, the author
describes the various physical properties of the metals, and then
enters into a detailed description of fuels and fire-clays. This is
followed by a full notice of each metal, and the methods em-
ployed for its extraction, the several metals being treated in the
following order :—Iron, cobalt, nickel, aluminium, copper, tin,
antimony, arsenic, zinc, mercury, bismuth, silver, gold, and

530 Notices of Books. (October,

platinum. The details of the metallurgical operations are
described with great clearness, and the author’s practical expe-
rience is sufficient guarantee that space is not wasted by the
description of processes which are either obsolete or im-
practicable. It should be remarked that the illustrations are in
most cases drawn to scale, and are consequently of great value
to those practically engaged in metallurgy.

In the Preface to this work Mr. Phillips tells us that his object
has been to supply such practical information on general prin-
ciples and typical processes as may not only afford a compre-
hensive view of the science and art of Metallurgy, but will also
enable the reader to study with advantage more elaborate
treatises and original memoirs on special departments of the
subject. This being the end which Mr. Phillips has set before
him, he deserves to be heartily congratulated on its successful
realisation.

¢
Le Monde Microscopique des Eaux. Par JuLEs Girarp. Paris:
J. Rothschild.

A poputar treatise on the marvels, animal and vegetal, of pond-
life, as revealed by the microscope. The remarks on the con-
struction and use of this instrument err, if at all, on the side of
brevity. The work is furnished with a great number of illustra-
tions, some of which, however, are deficient in that precision
and accuracy of detail which can alone give any real value,
whilst others—i.e., a general view of the vegetation on the
margin of a ditch—are rather ornamental than useful.

ae Seay

1874.] ( 537 )

PROGRESS IN SCIENCE.

MINING.

IT might naturally be expected that at the recent meeting of the British
Association considerable interest would be created by the iron-mines of
Antrim. Within the last few years workings have been opened in all direc-
tions throughout the county ; and indeed this remarkable development of iron-
mining forms an important chapter in the industrial history of the North of
Ireland. Notto mention the early notices of these ores, even'in the beginning of
the seventeenth century, we may remark that the ferruginous bands inthe basalt
of the Giant’s Causeway were observed by the Rev. Dr. Hamilton, and spe-
cially mentioned by him, in 17g0. No workings, however, were established
until 1861, when Dr. Ritchie, of Belfast, opened up the deposit of ore at
Ballypalidy, near Templepatrick. Brought into the market under the name
of ‘‘ Belfast aluminous ore,” this mineral became largely used for mixing with
other ores, especially with the rich hamatites of Cumberland and Lancashire ;
the high percentage of free alumina in the Belfast ore acting as a capital flux
to the siliceous hematite, and contributing to the formation of a good free-
flowing slag. The composition of this Irish ore brings it into close relation
with the mineral known as Bauxite, which occurs in the South of France and
in Carniola, and is employed both as an ore of aluminium and as a fettling
material for puddling-furnaces. The remarkable deposits of iron-ore now
worked in other parts of Antrim differ for the most part from those of Bally-
palidy, and often present a curious pisolitic stru@ture; the spheroids, which
are sometimes magnetic, being embedded in a matrix of brown or reddish
iron-ochre. This pisolitic ore contains from 30 to 65 percent of metallic
iron, whilst the aluminous ore yields from 20 to 28 per cent of iron: even the
ochres and lithomarge, though containing much less iron, have also been used
in the blast-furnace. The beds of pisolitic iron-ore appear to lie all on one
geological horizon, and thus divide the great series of basaltic rocks into two
well-defined groups—one below and the other above the level of the iron-ores.
It is probable that the Miocene ores of Antrim may have been formed
originally from the products of decomposition of the basalt, and the deposition
of these products under lacustrine conditions. The characters and distribution
of these ores have been well described by Mr. Ralph Tate and Dr. Sinclair
Holden, in the ‘“ Journal of the Geological Society ;” by Prof. Hull, in * Iron ;’”
and by Mr. R. A. Watson, in the “‘ Dublin University Magazine.” A brilliant
future for the north-eastern corner of Ireland may be foreseen in the develop-
ment of these important iron-making resources.

Among the papers read at the recent meeting of the Iron and Steel Insti-
tute, at Barrow-in-Furness, we may refer specially to one of local interest, by
Mr. P. Wirzburger, of Dalton-in-Furness. This memoir, ‘On the Geology
of the West Coast Iron Districts,” described the structure of the country
which the Institute was then visiting, and dwelt especially on the mode of
occurrence of the red hematite, which forms the staple of the great iron-
manufacture of this district. These ores are found partly as veins in the
Lower Silurian rocks, but mainly as deposits in the carboniferous limestone.
The ore in the limestone occurs under several conditions: sometimes in flat
deposits, following more or less closely the dip of the strata; sometimes in
veins, with an inclination greater than that of the enclosing rock; and in
other cases in irregular deposits, filling hollows or caverns in the limestone.
In the Furness district most of the deposits are covered with superficial drift,
but around Whitehaven they are generally enclosed in the solid limestone.
In consequence of the great irregularity in the distribution and size of the
ore-deposits the mining operations are rather precarious; borings in search of
the ore are made at random, and it is impossible to estimate, with anything

538 Progress in Science. { October,

like an approximation to accuracy, what extent of hematite still remains
unwrought.

It may be well to remark that a description of the hematite deposits of
Whitehaven and Furness, by Mr. J. D. Kendall, was laid before the Geolo-
gical Society of London at its last meeting.

Whilst the occurrence of valuable hematite in Furness has led to the
establishment of a vast industry in this district, it is to be regretted that coal
has not been found in the neighbourhood of the ores. Search has been made
from time to time, but hitherto without success. The most promising of
these undertakings is that at Rampside, where a boring was commenced about
five years ago, and has been energetically prosecuted in the face of great
difficulties. Mr. Alexander Brogden, M.P., read a paper on this boring to the
Iron and Steel Institute. For some time past the diamond-boring machine
has been at work here, and at present the bore-hole has reached a depth of
1450 feet.

Irish coal-mining is carried on to so limited an extent that we may fairly
call attention to the Tyrone coal-field, which ought to be developed with great
benefit to the North of Ireland. Mr. E. T. Hardman, of the Geological
Survey, has recently described this field. It measures only about 2} miles in
length by 1} mile in width; but although of so small an area it contains
about twenty-four seams, of which at least thirteen are workable. They all
consist of highly bituminous coal, of true Carboniferous age; fire-damp is
almost unknown in the pits. Mr. Hardman estimates that the field still con-
tains from 30 to 40 millions of tons of coal. Iron-stones are associated with
the coal, though not in sufficient quantity to admit of being profitably worked,
but the fire-clays in the upper part of the measures are largely used for the
manufadiure of bricks and tiles.

At a meeting of the Institute of Mining and Mechanical Engineers, recently
held at Cardiff, a paper of much interest, “On the Coal-Fields of South
Wales,” was read by Mr. Forster Brown, the President of the South Wales
Institute of Engineers. After tracing the history of iron-smelting in this
district, he described in detail the geological structure of this field. Practically
the field is divided into two separate parts, by an anticlinal ridge running ina
sinuous east and west course. In passing from one part of the field to
another, a change may be observed from bituminous coal to anthracite: this
change operates both horizontally and vertically; thus, in passing from east
to west the coal becomes, as a rule, more anthracite, whilst in other cases
the upper seams in a vertical section may be more bituminous than the
lower. Mr. Brown contrasted the modes of working coal in South Wales
with those followed in the North of England.

To the same meeting a paper “ On the Coal-Fields and Mining Industries
of Russia was communicated by Mr. J. B. Simpson, who had recently visited
some of the Russian collieries. The coal-fields of Russia may be referred to
three distri¢ts :—the Tula coal-field, at present but little worked; the Donetz
field, embracing a great thickness of good coals, partly bituminous and partly
anthracitic; and a long narrow coal-field at the base of the Ural Mountains.
None of the coal in these districts is of true Carboniferous age, and indeed
the only coal-measure fuel belonging to Russia is to be found in a small, but
productive, basin in Poland—perhaps an extension of the coal-field of Upper
Silesia.

Attention has been directed, by Mr. P. Le Neve Foster, jun., to the coal-
fields of Italy. It appears that Italy does not possess any coal of the true
Carboniferous period, but many of the tertiary lignites are of very superior
quality, and consequently well worth the expense of working. Mr. Foster has
examined and described the coal-fields of the Tuscan Maremma, which are
split up into a series of small basins by intrusions of eruptive rocks.

Three Reports on the Coal-Fields of Victoria have been drawn up by the
Board which was appointed some time ago, by the Minister of Mines, to in-
vestigate and report upon the coal resources of the Colony. The fields of

1874.] Metallurgy. 539

Loutit Bay, Apollo Bay, and the Wannon, have been examined, but the result
is by no means encouraging. Mr. Mackenzie, the Government Examiner of
Coal-Fields in New South Wales, has reported that—in spite of what may
have been said to the contrary—no workable seam of coal has yet been
opened up in any part of Victoria. The Board consequently does not feel
justified in recommending the expenditure of more money in boring for coal.
The most important fuel in the Colony appears to be the lignite of Lal-lal,
where a deposit occurs not less than roo feet in thickness. This lignite has
been described before the Geological Society of London, by Mr. R. Ethe-
ridge, jun.

But if Victoria is not blessed with coal, it has extraordinary treasures in its
gold-fields. A Report on the Mineral Resources of Ballarat, by Mr. R. A. F.
Murray, has been issued by the Geological Survey of Victoria. Not only is
the geological structure of the country described, but the intricate system of
auriferous ‘leads’? has been worked out with much care. The gold-bearing
drifts, associated with volcanic rocks which have been erupted at different
periods, are classified under four heads. In connedtion with these drifts it is
interesting to study the distribution of the quartz-reefs. It may be regarded
as established that the supply of alluvial gold was derived from veins disinte-
grated during the various drift-periods, and that the gold—except in very fine
particles—has not travelled far from the spot where it was separated from its
parent-rock. In the distri@ around Ballarat the richest ground is always in
the neighbourhood of the quartz-reefs.

METALLURGY.

At the recent meeting of the Royal Cornwall Polytechnic Society a good
deal of interest was excited by Mr. King’s Patent Magnetic Ore Separator.
This apparatus is used for the separation of minerals containing iron, in cases
where the iron-ore is associated with other minerals. It is at present em-
ployed at the Ballycorkish Mines, in the Isle of Man, where the ore consists
of a mixture of galena, blende, and spathose iron-ore. The lead-ore may be
readily separated by taking advantage of its high specific gravity; but the
blende and spathic ore, being of nearly the same density, could not be properly
separated by even the best systems of sizing and mechanical dressing. Hence
the introduction of the Magnetic Separator. The stuff, after being crushed,
is roasted at a dull red heat in revolving retorts, when the carbonate of iron
is decomposed, and a magnetic oxide produced. The roasted ore is ther
transferred to the hopper of the magnetic apparatus. This consists of a large
drum or wheel, about 18 inches in diameter and ro inches in breadth, furnished
within with a system of magnets arranged radially. The mixed ore, in its
passage over a series of four of these drums, has its magnetic portion gra-
dually separated by attraction, and the part which escapes the magnetic drum
is clean blende. Mr. King proposes to apply his system to the separation of
tin-ore from the iron-pyrites, copper-pyrites, and mispickel, with which it is
frequently associated in our Cornish mines. Wher these mixed ores are
roasted, the pyrites may be transformed into magnetic pyrites.

“Our Tin Produdion and Tin Trade” formed the subje& of a valuable
paper, by Mr. Robert Hunt, F.R.S., recently contributed to the Miners’
Association. According to the returns of the Board of Trade, the exports of
tin of British production was 114,201 cwts. in 1871, 113,871 cwts. in 1872, and
115,946 cwts. in 1873. Of tin of foreign and colonial production we exported
41,196 cwts. in 1871, 48,634 cwts. in 1872, and 28,869 cwts. in 1873. Cornwall
has now to compete not only with the tin production of “the Straits,’ in-
cluding the Malacca Peninsula and the islands of Banca and Billiton, but
also with the newly-discovered tin districts of Queensland, New South Wales,
and Tasmania.

Mr. Crampton’s revolving furnace for puddling iron was described by the

inventor in a paper recently read before the Iron and Steel Institute. Small
coal or slack is utilised as fuel, and is introduced with a current of air in such

540 Progress in Science. (October,

a way as to ensure perfect combustion, and the consequent absence of smoke.
The fuel and air are fed automatically into the revolving furnace in which the
puddling is effected, and therefore without the mediation of a separate com-
bustion-chamber. A very intense, though regular, temperature is obtained,
and the phosphorus and sulphur are said to be eliminated to a very large
extent from the pig-iron. The furnace is recommended not only by its
economy of fuel, but also by the rapidity with which the puddling is effected.
With a furnace 12 feet in length and 6 feet in diameter, the inventor has
puddled pig-iron in an hour and a quarter from the time when it was cold.
The revolving portion of the furnace is protected by a water-casing, and the
difficulties of contraction and expansion incident to other revolving furnaces
are said to be completely conquered.

The other papers bearing on Metallurgy brought before the Institute were
for the most part on mechanical subjects. Among these we may mention one
by Mr. Holley, of New York, descriptive of the general arrangement and
principal details of the plant used in America for rolling steel rails.

MINERALOGY.

In compliment to the late M. Rivot, of the Ecole des Mines, the name of
Rivotite has been bestowed upon a new mineral, which occurs in irregular
masses disseminated through limestone on the west side of the Sierra del
Cadi, in Lerida, Spain. It is an amorphous, compact, opaque mineral, varying
in colour from yellowish-green to deep greyish-green. From its analysis the
following formula may be deduced :—Sb20;+4(Cu,Ag)O.

The memory of Dr. Livingstone is to be perpetuated in a new mineral spe-
cies found at Huitzuco, in the State of Guerrero, Mexico. Livingstonite
resembles ordinary antimony-glance, or stibnite; but with its lead-grey colour
gives a red powder, and is thus distinguished from the antimony-ore. More-
over, M. Mariano Barcena, who has named the species, found it to contain
Io per cent of mercury, and it appears, indeed, that Livingstonite is a double
sulphide of mercury and antimony.

Guanovulite is the name under which Dr. F. Wibel proposes to distinguish
a pale yellow crystalline body which occurs associated with the eggs some-
times found in deposits of guano. Analysis shows it to be a hydrous
sulphate of ammonia and potash, with an acid sulphate of potash.

Prof: Vom Rath, of Bonn, has described a new zeolitic mineral from the
granite of the Isle of Elba. Foresite, as the new mineral is called, was found
near the village of San Piero in Campo, and occurs in association with other
zeolites, such as stilbite and heulandite. It is a hydrous silicate of alumina,
lime, and soda, crystallising in the orthorhombic system. The name is com-
plimentary to Sig. R. Foresi, of Portoferrajo, who has done much to aid in
keeping up an interest in the mineralogy of Elba.

Under the name of Veszelyite a new mineral has been described by Prof.
Schrauf, of Vienna. It is a hydrated phosphate of copper, presenting a
bluish-green colour, and crystallising in the triclinic system. The mineral
occurs on garnet, at Morawitza, in the Banat.

In continuation of Mr. E. S..Dana’s researches on the crystallography of
Datholite, he has applied himself to the study of the fine specimens in the
K.K. Hof-Mineralien Kabinet at Vienna, and has published his studies in
Tschermak’s ‘* Mittheilungen.”

A valuable series of mineralogical contributions has been submitted to the
German Geological Society by Herr Max Bauer, of Berlin, and published in
the Society’s “‘ Zeitschrift.” These studies relate to the rarer forms of garnet,
to the physical properties of mica, the optical characters of margarite, the
twin-striz of iron-glance, and some peculiar crystals of smoky quartz from
Switzerland. -

7 As] Engineering. 541

ENGINEERING—CIVIL AND MECHANICAL.

The past season has, as is usual at that time of the year, been devoted to
the meetings of Associations, at which engineering science has been largely
represented. Section G of the British Association is devoted to mechanical
science: a considerable amount of what is interesting to mechanical engineers
finds its place in papers read at the autumnal meeting of the Iron and Steel
Institute, as well as at the meetings of the Mechanical Engineers.

British Association.—Professor James Thompson, President of Seéion G,
drew attention in his Address to the important question of railway accidents
and the means of their prevention, and he traced the gradual development of
progress in mechanical improvements as applied principally to points and
signals. As this will form the subject of a separate article in a future number
of the « Quarterly Journal of Science,” we shall not dwell further upon it on
the present occasion. From thence the Professor referred to the subject of
steam navigation, the rapid progress of which he attributed mainly to the
introduétion jointly of the screw propeller, the compound engine, steam
jacketting of the cylinders, superheated steam, and the surface condenser.
The invention of the screw propeller has enabled steam to be used as an
auxiliary motive-power in ocean steamers, for which paddles were inapplicable,
whilst the other improvements have tended to an economy in fuel—an essential
object in long voyages,—and by the use of which the consumption of coal is often
now found to be reduced to about 2 lbs. per indicated horse-power per hour,
from having been 4 lbs. or 5 lbs. in good engines in times previous to about
twenty years ago. Deep sea sounding was next reviewed, and Sir William
Thomson’s new machine referred to, with which soundings have been made in
the Bay of Biscay, and a specimen of the bottom brought up from a depth of
2700 fathoms, or a little more than three miles. One important feature in
this machine consists in a fri€tion brake arrangement, by means of which the
arrival of the sinker at the bottom is indicated very exactly on board the ship.
The illumination of lighthouses was next considered, the improvements in
which were briefly explained. The practicability of employing gas has been
one great movement in advance, and Sir William Thomson has recently
succeeded in perfecting a self-signalling apparatus, by which different light-
houses may readily be recognised and distinguished from one another, and
which is about to be adopted by the Belfast Harbour Commissioners. The
Dublin harbour works carried out by Mr. Bindon Stoney, with concrete
masonry blocks of 350 tons weight each, to which Mr. Thomson referred, has
already been explained in Engineering Chronicles ona former occasion. From
these subjects the Professor next branched off into the regions of sanitary
engineering, wherein he dwelt principally upon the defective drainage and
ventilation of our buildings, and the smoke nuisance of our towns. With
reference to the latter subject he pointed out the economy that resulted from
the use of well-known mechanical contrivances for the more effectual com-
bustion of coal, and he instanced a case where one method is applied to about
thirty ordinary 40 horse-power boilers, in which upwards of roo tons of coal
are burned daily, and from the chimneys of which not more smoke is emitted
than from many a kitchen fire. By the adoption of this method the bed of
coal, which is gradually supplied in front, is caused to travel along the bars
towards the inner end of the furnace, and the combustion proceeds in a very
uniform manner in conditions highly favourable to economy of fuel, and
without the emission of almost any visible smoke.

We shall notice two papers that were read before this Section, viz., “On
the Upper Bann,” by John Smyth, and ‘‘ On the Eclipsing Apparatus at Holy-
wood Lighthouse,” by Mr. W. Bottomley.

The former paper gave an account of recent works undertaken for improving
the water supply of the river Bann for the mills which are established on its
banks ; for this purpose, the Bann Reservoir Company was formed in 1835,
and by its means the Loughislandreavy reservoir was finished in 1839, and
the Corbet reservoir in 1847. Loughislandreavy reservoir is situated in a
narrow valley in the flank of the Mourne Mountains, and receives three-fourths

VOL. Iv. (N.S.) 30

542 Progress in Science. (October,

of its supply through a conduit or feeder from the Muddock River
and one-fourth in the same manner from the Moneyscalp river. The

water is impounded to a depth of 35 feet above the old lake which existed
there, and can be drawn off to a depth of 38} feet below top water. The area
of the old lake was 93 acres, and that of the present reservoir 250 acres, and
the capacity 270 million cubic feet. The embankments are substantially
constructed, and protected against the wash of the water by strong stone
pitching. An important and most successful speciality in their construction
was the use of peat as a supplementary aid to the puddle. The water is
discharged through two 18-inch iron pipes, secured in a culvert built in the
solid ground beneath the main embankment, and is conducted by an open
channel to a point about 1 mile down stream from where the supply is lifted.
The water from the reservoir reaches the Bann after flowing down the Muddock
for 6 miles. From the mouth of the Muddock to the weir, where the surplus
water of the Bann is lifted for the Corbet reservoir, there is about 4o feet of
unoccupied, and 74 feet of occupied, fallonthe Bann. At this weir the care-
taker daily measures the quantity of water coming down the river, and thereby
regulates the amount to be supplemented by the reservoirs. The channel of
the feeder from this weir to the Corbet reservoir is about a mile long, and
wide enough to take in considerable floods. The area of the reservoiris about
70 acres when the water is at top level, or 114 feet above discharge outlet.
The water is discharged through small iron sluices into a conduit communica-
ting with the river. The cost of these works has been about £30,000.

In the paper upon lighthouse illuminations the author observed that in
order, under present arrangements, to make out with certainty what any
observed light is, it is necessary that the master of the vessel shall first
ascertain the position of his own ship. In many cases this cannot be done
even in short voyages, but after a long voyage, and with but few opportunities
for making correct observations, errors of many miles may occur in a ship’s
reckonings. Every year the accounts of shipwrecks show the fatal results
arising from the mistake of one light for another light many miles away: the
signal which properly interpreted should have preserved the mariner from
danger, misinterpreted becomes the false guide which lures him to destrudtion.
Even coloured lights do not afford the required protection, but what is required
is that each light should unmistakably declare its own identity ; and the plan
for effecting this, which was first proposed by Charles Babbage, in 1851, and
has recently been perfected by Sir William Thomson, is that each lighthouse
shall exhibit from sunset to sunrise a certain definite series of eclipses repre-
senting one of the letters of what is known in telegraphy as the Morse
alphabet. This method has recently been adopted by the Harbour Commis-
sioners of Belfast for the light on the Holywood Bank, where, by the use of
three shutters, or screens, two short eclipses and one long eclipse are given,
corresponding to the letter U in the Morse alphabet, and the system will
therefore receive a fair trial.

The majority of the papers read before the Iron and Steel Institute at their
meeting at Barrow-in-Furness belonged more to geology than engineering,
but two of them may be classed under the latter heading—one being a paper
by Mr. Robert Luthy, ‘“‘On Valves Suitable for Working Hydraulic Machi-
nery ;”’ and the other, by Mr. T. Wrightson, of Stockton-on-Tees, ‘‘On a New
Form of Wagon Drop for Blast-Furnaces.”’

In the former paper it was explained that under high pressures the old-
fashioned taper, or circular, valves are not reliable; brass slide valves of the
usual D pattern, similar to steam-engine slide valves, do very well for smaller
sizes, and if their working faces are made of hard metal they last a consider-
able time; but for the larger sizes the friction becomes so great that, in order
to work them by hand, a very great leverage has to be employed, and this
prevents the valves being opened or closed quickly enough. Mitred plug
valves are used in some places, but they are complicated and expensive, and
require a great deal of room. The foregoing arrangements of valve have all
metal faces, but recently valves have been introduced in which the peculiar
properties of the leather collars for making hydraulic joints have been applied

1874.] _ Engineering. 543

to the best advantage. The leathers, it is found, last a very long time, and if
a valve has to be examined, or fresh leathers put in, it can be done in a few
minutes, whereas the repair of metal-faced valves is both tedious and expensive.

In the ordinary form of wagon drop a frame-work, usually of cast-iron
columns, braced well together, supports an entablature, on the top of which is
mounted a strong shaft with two large sheaves keyed thereon, to one or both
of which is applied a powerful brake, worked by a lever from the upper rail
level. The cage moves up and down in guides fixed to the frame-work, and
is suspended by chains or wire ropes descending from one side of the sheaves,
whilst from the opposite side hang heavy counterweights, which are suffi-
ciently in excess of the weight of the cage to draw it to the top when the
wagon is not on. Instead of weights Mr. Wrightson proposes to use water
as the controlling agent in the drop. It would occupy too much space to
enter into a description of how this is arranged, but it will be readily under-
stood by anyone acquainted with the general principles of hydraulic machinery.

Mr. F. J. Bramwell, as President of the Institution of Mechanical Engineers,
recently delivered a very remarkable address on the performances of his
profession and the progress made in mechanical science, from which it would
seem that the mechanical engineer is necessary to our very existence, and
that few modern improvements could have been adopted without his aid, and
yet he urged that there was no reasun for supposing that the time had arrived
when there need be any slackening in the development of engineering science,
for there remain vast fields of research in which the ground has as yet scarcely
been broken, while there are others practically untouched, and, even in those
departments of engineering in which most progress has been made, far more
remains to be done than has yet been accomplished. The waste of fuel was
dwelt upon, and Mr. Bramwell remarked that for years past there have been
constructed steam-engines capable of developing all the power at present
obtained by the use of such engines, with the consumption of but little, if any,
more than one-third of the fuel actually expended for that purpose, while in
our metallurgical and manufacturing processes parallel instances exist.
Attention was also directed to the transmission of power over long distances,
for which purposes the chief methods adopted are by a fast running rope, by
the exhaustion or compression of air, or by the flow of water through pipes
under pressure. Amongst other subjects dwelt on’ were the substitution of
mechanical for human labour; the mode of joining materials, and the -
abvisability of devising some mode less crude than the present practice of
employing bolts and rivets; on the utilisation of so-called “* waste” produéts ;
on the advantages which the present generation of engineers may be expected
to derive from the spread of technical education, and on the disadvantages
which, on the other hand, are attendant on the modern tendency towards
subdivision in engineering manufactures.

The first paper read was one by Mr. John McConnochie, of Cardiff, “On
the Bute Docks and the Mechanical Arrangements for Shipping Coal.” The
dock accommodation at present existing affords a water area of 77 acres, to
which will be added a further area of 54 acres when the new Roath Dock is
completed. As the tidal water at Cardiff carries a deal of silt in
suspension, and is therefore not suited for supplying the docks, they are fed
with water drawn from the river Taff about 2 milesabovethem. Inconnection
with the harbour accommodation there are at present four graving docks.
The lock gates, as well as a large swing bridge over a junction lock, and the
various hoists, tips, &c., connected with the new basin, are all actuated by
hydraulic machinery supplied by Sir W. G. Armstrong and Co. As the pre-
ponderance of the trade of the port consists of exports, vessels arrive in ballast,
and there are seven steam cranes specially employed in the discharge of this
ballast, four of which are capable of discharging 200tonseach perhour. These
steam cranes discharge into railway wagons, by which the ballast is con-
veyed a distance of about 2 miles to spare land, where it is deposited. The
mechanical arrangements for shipping coals at the West and East Docks are
on the high level, or balanced principle, but at the New Basin the low level
system has been adopted into hydraulic tips for elevating and lifting the

544 Progress in Science. ‘O¢tober,

wagons. The provision for loading coals consists of thirty-one balance tips
and twelve hydraulic tips, or forty-three in all; and, as each tip is capable
of shipping 560 tons of coal per day of ten hours, the total shipping capacity
of the Bute Docks is nearly equal to 8 millions of tons per annum.

We have to record the death, during the past quarter, of more than one
eminent member of the Engineering Profession, amongst whom we may note
Mr. T. Marr Johnson, Mr. John Grantham, Sir Charles Fox, Sir John Rennie,
and Sir William Fairbairn. Sir William Fairbairn was born at Kelso, on the
oth of February, 1789, his parents occupying a comparatively humble position
in life. His first occupation was at the age of fourteen, when he obtained
employment on the new bridge at Kelso, which was being erected by
Mr. Rennie. Afterwards he was employed by his father on the Percy Main
Colliery, of which he was manager, and at the age of sixteen he was appren-
ticed to the Colliery Company, and he commenced a course of self-education.
At the age of twenty-one years he found his way to London, where he first
obtained work at Grundy’s Rope-Faétory, at Shadwell, and afterwards was
engaged by Mr. Penn, at Greenwich. Afterwards he worked at the Phoenix
Foundry, Dublin, and in 1814 he made his way to Manchester, where he
settled as a working millwright under Mr. Adam Parkinson. After two years
he married, and commenced business on his own account, one of his first
efforts at engineering designing being the plans for an iron bridge over the
River Irwell, at Blackfriars. Fairbairn gradually rose to a position of
eminence, and in’1831 he construéted one of the earliest examples of iron
ship-building, the success of which led to the establishment of the well-
known works at Millwall. He was engaged with Robert Stephenson in
designing and constructing the Britannia Tubular Bridge. In course of time
the firm of which Sir William was the leading partner was turned into a
Limited Liability Company, and one of the latest works of importance turned
out by it was the construction of the iron forts for the defence of Spithead.

GEOLOGY.

Glacial Geology.—The glaciation of the South-West of England has lately
attracted some attention. Mr. Croll, speaking of the Great Baltic glacier,
ooo or 2000 feet in thickness, is of opinion that if it be admitted that it
passed over Denmark,—and of this there is good geological evidence,—then it
is hardly possible to escape the conclusion that a portion of it at least passed
across the South of England, entering the Atlantic in the direction of the
Bristol Channel. Mr. W. C. Lucy has detected Glacial strie on a mass of
sandstone near Porlock. Mr. H. B. Woodward has recorded the occurrence
of Boulder Clay near Yarcombe, on the Black Down hills. Looking to the
nature of the deposits found on these hills, he thinks that their formation may
be attributed to marine action during the glacial submergence, with the
assistance of an occasional iceberg to bring the foreign material (quartz and
quartzite) which is mixed with the flint and chert drift.

Mr. T. F. Jamieson has arranged the Glacial phenomena of Scotland under
three heads:—(r), the great early glaciation by land-ice; (2), the period of
glacial marine beds containing remains of Arétic Mollusca, when most of the
country was covered by the sea; (3), the time of the late glaciers, the special
subject of the paper. He described this last period as one not of mere local
glaciers, but as characterised by a return of a great ice-sheet over nearly the
whole of Scotland and Ireland; and he stated that this ice-sheet was probably
neither so thick, so extensive, nor so enduring as that of the first period of
glaciation, which cleared away everything in the shape of superficial deposits
down to the hard rock. He believed, however, that in the last period the
mountains of Scotland and Wales, as well as the Pennine range and the rest
of the North of England as far as Derby, were covered with thick ice, which
in most parts reached down to the sea, and that extensive snow-beds prevailed
over the rest of England. In the summer months the melting of these would
give rise to streams of muddy water, and produce the superficial deposits of
brick earth, warp, and loess; whilst, when the currents were stronger, perhaps

4
,
q
'
i

1874.] Geology. 545

from the thaw being unusually rapid, deposits of gravel would be formed.
This second ice-sheet would gradually become less, and break up into valley-
glaciers, which in theirretreat would leave kaims and eskers at low levels, and
moraines in the mountain-glens, During this time no new great submergence
of the country took place; and the last great modifications of the surface
were subaérial, and not submarine, the work having been done by frost, rain,
and glaciers.

Mr. J. G. Goodchild has described the Glacial phenomena of the Eden
Valley and the Western part of the Yorkshire Dale distri. He considers
that they could not possibly have been produced by floating ice, and therefore
must have been caused by land-ice. The flow of ice evidently came from the
Scottish southern uplands, and it could not well have exceeded 2400 or
2500 feet in thickness.

Stratigraphical Geology.—The exact relations of the Keuper and Bunter
divisions of the Trias, in the British Isles, have never been fairly established.
Mr. J. Anderson points out that in County Down they appear conformable,
whereas near Nottingham the Keuper is said—by the Rev. A. Irving—to rest
upon the eroded surface of the Bunter. Mr. Irving has noticed clear signs of
continuous deposition of the Permian and Lower Bunter rocks in the Not-
tingham district; and this fact is important, considering that one series of
rocks is classed as Palzozoic, the other as Mesozoic. Mr. H. B. Woodward,
referring to the Red Rocks in the South-West of England, remarks upon
the continuous series of rocks from the breccias and sandstones of Dawlish
and Teignmouth up in to the Rhetic beds of Axmouth. Although the lower
portion of these Red beds has been called Bunter, and the upper Keuper, there
is no unconformity, and the Muschelkalk may, he thinks, be represented by
sediments of a different lithological nature to the continental beds. Never-
theless it is not well to make any subdivisions in this part of England
equivalent to those on the Continent, but rather to rest satisfied with terming
the whole series the Trias.

Mr. H. G. Seeley having visited the Devonian country in search of the fault
which the late Mr. Jukes supposed to traverse it, records his opinion that no
such fault exists. He thought that Mr. Etheridge’s detailed grouping of the
rocks was better suited to the north-west part of the country than West
Somerset, and that for that region the divisions of strata used by Mr. Jukes
were convenient.

Palzontology.—Mr. E. B. Tawney has described and figured nineteen new
species of Gasteropoda from the Inferior Oolite of Dundry Hill, near Bristol.
He also adds fifteen more species to the list of British fossils: altogether he
records sixty-six species in a determinable condition.

Dr. Nicholson has described a new genus of tabulate corals, Columnopora.
intermediate between Favosites and Columnaria, of which only a single species
has been obtained from the Hudson River Formation of Ontario and Ohio.

The occurrence of Labyrinthodont remains in the Yoredale rocks of Wens-
leydale has been noted by Mr. L. C. Miall.

Prof. Young and Mr. John Young have described two new forms of Polyzoa
from the Carboniferous Limestone shales near Glasgow, under the names of
Actinostoma and Glauconome. Referring also to the genus Paleocoryne
(described by Dr. Duncan and Mr. H. M. Jenkins), they maintain that the
structures are not independent organisms, but mere processes of the Polyzoa
on which they occur, the cells at the base being only the cells of the Polyzoa.

Mr. H. G. Seeley has recently described the tibia of a large struthious bird
(Megalornis) from the London Clay of Eastchurch, in Sheppey. Mr. Seeley
has also founded the genus Ophthalmosaurus for some reptilian remains from
the Oxford Clay.

Sub-Wealden Exploration.—The boring has now reached a-depth of upwards.
of 1000 feet. The beds traversed have been proved to belong to the Lower
Wealden, Purbeck and Portland Series, and Kimmeridge Clay. The Oxford.
Clay has been last detected. The Committee—represented by Prof. Ramsay,

546 Progress in Science. (October,

Mr. John Evans (President of the Geological Society), and Prof. Prestwich—
make an earnest appeal for further assistance to carry on the work.

The Steppes of Siberia.—Mr. Thomas Belt has described some seions
examined by him on a portion of the Siberian steppes, which have enabled
him to form an opinion as to the origin of the great plain. The best section
seen by him was at Pavlodar, which showed 50 feet of sand and silt, with
occasional lines of pebbles. South of Pavlodar the surface of the ground was
covered with pebbles, which became larger in advancing southward, until the
soil was full of large angular quartz boulders. Further south the bed-rock
comes to the surface in ridges and low hills, increasing in height until some
of them ‘attain 2000 feet. All the rock-surfaces were much shattered, as if by
the action of frost, but they showed no signs of glacier-action. The generally
accepted marine origin of the great plain was said to be negatived by the
absence of sea-shells in its deposits, whilst Cyrena fluminalis occurs in them.
The author regards them as deposits from a great expanse of fresh water kept
back by a barrier of polar ice descending far towards the south. In its greatest
extension this ice-barrier would produce the crushing of the bed-rock; and as
it retreated, the water coming down from the higher ground in the south would
cover a continually increasing surface. The distribution of the boulders on
the plain north of the ridges was attributed to floating ice.

Professor of Geology at Oxford.—Mr. Joseph Prestwich, F.R.S., &c., has
been appointed to the office of Professor of Geology in the University of
Oxford, as successor to the late Prof. Phillips. The Council of the Institution
of Civil Engineers have recently awarded to him a Telford Medal and
Premium, for his paper ‘‘On the Geological Conditions affecting the Con-
struction of a Tunnel between England and France.”

Dr. F. Stoliczka.—Paleontological Science has lost one of its ablest
students in the death of Dr. Stoliczka, at the early age of 34. He is known
chiefly through his connection with the Geological Survey of India, by his
descriptions of many of the fossil organic remains collected by the Staff. For
several years he was Natural-History Secretary to the Asiatic Society of
Bengal, and itis mainly to his exertions that this Society owes the resumption
of much of its early vigour.

PHYSICS.

Licut.—M. Rayet has published a ‘‘ Note on the Spectrum of Coggia’s
Comet.”” On May 1g the light gave a continuous spectrum from the orange to
the blue (spectrum of solid nucleus) traversed by three bright bands (spectrum
of gaseous nebulosity) ; but the continuous spectrum was very narrow com-
pared with the ordinary nuclear spectra; and the luminous bands, instead of
being stumped towards the more refrangible side, terminated, towards red and
violet, in very distiné straight lines. Father Secchi also writes: On June 18
and 1g the spectrum with the bands of carbon was considerably developed,
the green band remaining the more distin&, whilst in the comet of Temple
the yellow was brightest. This proves that the gaseous compounds are not
the same in all comets. At the beginning of the month there was merely a
spectrum of bands, now there is a general connecting line which unites them
into one continuous spectrum. ‘The bands of the comet are more diffuse than
those of carbonic oxide. They resemble the spectrum obtained by the electric
spark in the vapour of benzine.

A new helioscope has been construéted by M. Prazmowski. The idea of
employing the polarisation of light in place of coloured glasses to diminish
the lustre of the sun is not novel; but the quantity of light reflected, even
under the Brewsterian angle for glass of a low index (1 =1°'5) is so considerable
that the eye cannot support the light. The author obviates this difficulty by
taking a rectangular prism of an index, 2, and cementing upon its hypothenuse
another similar prism, so as to form a cube. The index of the second prism
isn'. A ray of light meets in its course the first hypothenuse of the cemented

take Beate Ras : Sede. n :
pair with an incidence of 45°; this is the surface whose index is _. As — is
oe n n

1874.| Technology. BAT

very nearly unity, the angle of 45° is very near the Brewsterian incidence.
The instrument has been further modified by Janssen.

Microscopy.—Herr Moller has introduced a very ingenious modification of
his celebrated Diatomaceen typenplatte ; the old form had about four hundred
species neatly arranged in the space of about a quarter of an inch square, each
slide being accompanied by a manuscript catalogue. The new arrangement
consists of a photograph about 4 millimetres square, of eighty circles, ten in
a longitudinal and eight in a vertical direGtion; beneath each circle is the
name of the object and its author, and in the centre of each of these circles
is a diatom, and in many cases two are mounted in order to show front and
side views. The whole collection independently of its great value to the
student of Diatomacez is a marvel of manipulative skill.

Those who have attempted to dry the petals of Tvadescantia Virginica, have
probably noticed that the coloured cell contents break from their envelopes
and flow towards the margin of the petals, leaving the greater part in a
colourless condition. The petals and their alcoholic tin@ure giving an
interesting absorption spectrum of three bands, it has been a desideratum to
preserve the colouring matter in some permanent form for purposes of
reference and comparison; the alcoholic tinctures of most flowers rapidly fade,
and it is impossible to dry the very fleshy petals of Tvadescantia in the ordinary
way ; but the colour has been successfully preserved by mounting in balsam
by the ‘‘ Oil of Cloves’? process. The petals separated carefully from the
flower so as to avoid breakage or bruises are immersed in ordinary methylated
spirit and placed under the receiver of an air pump to ensure rapid displace-
ment of the contained fluid and air; they are next transferred to absolute
alcohol, the air pump being also used to save time, then placed in oil of cloves
until transparent, and can then be mounted in balsam, taking care that as little
heat as possible is employed. Petals of Cineraria and Lobelia speciosa also
make good objects for the micro-spectroscope. The colours are much more
brilliant than when dried petals are mounted in balsam, even in those plants
which can be successfully dried by the ordinary process.

An exhibition of high scientific value took place at the meeting of the
South London Microscopical and Natural History Club. This society has
increased so much during the three years of its career that it has been found
necessary to seek for a larger meeting-room, in which the first meeting was
held on the 21st July. Instead of an indiscriminate collection of obje&s being
exhibited, as at most conversaziones, the President, Dr. Braithwaite, F.L.S.,
determined to limit the exhibition to three subjects, viz., the cuticle of plants
and its appendages of hairs, scales, glands, &c.; cyclosis or circulation in
plants ; and the hard tissues of fruits. A very complete series of preparations
was shown, and in addition short lectures on each*subje@& were delivered by
the President and two other demonstrators conversant with their respective
departments. The educational success of the exhibition was so marked that
other meetings illustrating equally important points of minute structure will
follow, and probably replace the old fashioned and almost useless soiree,
which has hitherto been the only means of bringing the microscope and the
minute structure revealed by its aid before the general public.

Dr. J. G. Richardson exhibited at the Academy of Natural Sciences of
Philadelphia a new “Syphon Slide.” It consists of a slip of plate glass
3 inches x 1 inch or other convenient size, in the upper surface of which is
ground a shallow groove, elliptical both in its transverse and longitudinal
section, and deeper towards one end than the other. This excavation is
arranged so as to receive a small living fish, tadpole or other aquatic animal,
and retain it under sufficient constraint to prevent any troublesome move-
ments, and also to prevent any injurious pressure. The improvement over
other slides of this description consists of imbedding a small metallic tube
at each end of the cell, and adapting to each of these two tubes pieces of
elastic pipe, one being intended for the entrance and the other for the exit of
any fluid which it might be desirable to employ. For the examination of

548 Progress in Science. (October,

larger animals similar cells of suitable dimensions can be constructed of
larger and thicker pieces of glass. With such an apparatus a current of iced
water can be passed through the cell, and any injurious effects which might be
caused by the use of the electric- or lime-light entirely counteraéed. Animals
may be kept without injury in these cells for several days so long asa constant
current is maintained. This contrivance offers many facilities for prolonged
physiological investigations.

TECHNOLOGY.

Composition and analysis of the concentrated milk of the Anglo-Swiss
Company of Cham has been determined by M. A. Mintz. The reaction of
the milk is feebly alkaline, and its specific gravity is 1°313. Contrary to
what has been supposed, a certain quantity of inverted sugar is present. The
composition of two samples was—

No. 1. No. 2.

(CeinyeEREIe 65 oa oo 40 oo” Seite 29°4
ibe ENE 5G 55 bo 50) By 12°4
Mik Su canteen lilies amet 13'9
IBN Wa eae aoe aa | na, doy @ CFS 85
Casein, albumen, and salts .. 110 I2'0

NW WAWS? “Sal dor soda "oo! psy 257 23'8

I00'o I00°O

The amount of inverted sugar increases with keeping. The milks employed
in the manufa@ure of these two samples must have had the following
composition :—

No. 1. No. 2.
Milk-sugar.. .. 5°2)°_.. 5:2 .
Buttersen ie. pcs x7} 13°2 x2] 12"
Casein, &c. zs | solids solids
Water sie, saves BOOS 87°2
100°0 ~' | “00"o

These samples agree closely in their composition with a normal milk, which
may be taken as—

Milk-sugar .. .. -» 5°2
BNE G6 Go a5 da be +o} 130
Casein, &c. .. 3°8
Water? "sje ae) isle ewe aes 7eO

I00°o

The composition of this milk contrasts very favourably with that generally
supplied in Paris, which frequently contains not more than 7 per cent of
solids, of which 1°5 to 2 is butter.

According to Ch. Méne, Japan wax has been regularly imported into Europe
for some years, and is quoted at from rj to 2 frs. per kilo. It is extensively
used for the adulteration of bees’-wax, the value of which ranges from 3? to
4 frs. per kilo. This fraud may be detected by the specific gravity of the
sample. That of bees’-wax is 0'96931, that of Japan wax 1'00200. Yet all
the mixtures containing from 50 to go per cent of Japan wax are lighter than
bees’-wax.

M. d’Havrincourt colle@ed cockchafers at the price of a franc per ro litres,
and having destroyed them with gas-liquor and sulphuric acid, obtained a
good manure. A previous experiment, where the beetles were worked up with
lime, gave unsatisfactory results.

1874.)

(549 )

IONeD Ex

BSORPTION and _ fluorescent
spectra of the uranium salts,
investigation of, 133

— spectra, 134

Accidents, railway, 341, 413

Acetate, uranic, 135

— — anhydrous, 137

Acetates, double, 137

* Acoustics, Treatise on in connection
with Ventilation, and an Account
of the Modern and Ancient

Methods of Heating and Ventila-

tion” (review), 1:8

Advance of mechanical puddling, 407

Aérophore, ingenious apparatus for
the miner, 262

Agates and other siliceous stones,
phosphorescent glow shown by,

266

Age of American coals and lignites,

406

compressed, to

haulage, 120

— fresh, method for the obtaining of
in mines, 262

Alarum signals, 419

ALuan, Prof. W., ‘“‘ Theory of Arches”
(review), 531

Alloy, new, 264

Alloys, especially those of copper and
tin, researches on, 121

Analysis of Ashantee gold, 409

— — grain gold from a burn at Wan-
lock, 409

— — idocrase or vesuvian, 411

“Analysis, Quantitative Chemical”
(review), 107

Ancient volcanoes of the Highlands,
271

Anileney, copper ore in, 120

Anhydrous uranic acetate, 137

Annual International Exhibitions, 332

*‘ Animal Locomotion,” (review), 237

“Annual Record of Science and In-
dustry for 1872” (review), 111

‘¢ Antozone and Ozone; their History
and Origin” (review), 116

Antrim, iron mines of, 537

‘‘ Appliances, Workshop” (review),
10g

Air, underground

VOL. IV. (N.S.)

Application of compressed air to
underground haulage, 120

‘‘ Applications of the Spectroscope”’
(review), 102

ARMSTRONG, H. E., ‘‘ Introduétion to
Organic Chemistry ” (review), 250

*¢ Art and Science, Year-Book of Faés
in” (review), 403

Artificial crystals of metallic anti-
mony, 408

Artillery matériel,
changes in, 40

Ashantee gold, analysis of, 409

Asmanite, study of, 265

ASSELIN, M., glycerin to prevent in-
crustations in steam-boilers, 419

ATKINSON, E., ‘ Physics, Experi-
mental and Applied, for the Use
of Colleges and Schools” (review),
II

Atmosphere, observations on the
optical phenomena of the, 34

Atomic matter and luminiferous ether,
180

AuTHaus, J., ‘ Medical Electricity,
Theoretical and Pra@tical, and its
Uses in the Treatment of
Paralysis, Neuralgia, and other
Diseases” (review), I17

British, recent

BAe M., memoir of the Caspian
Sea, 127

Bain, A., ‘‘Mind and Body; the
Theories of their Relation”
(review), 113

BAINBRIDGE, E., prevention of colliery
explosions, 262

Barrp, S. F., ‘‘ Annual Record of
Science and Industry for 1872”
(review), 111

Baker, B., ‘“‘Long Span Bridges”
(review), 118

Balsam, preparations in, 273

BarBER, S.,observations on the optical
phenomena of the atmosphere, 34

BarsiER, M., electric cable against
fires, 419

Bartow, Mr., nature and uses of
modern steel, 122

Barnasy, N., designs for ships, 412

4A

550

Barometric and thermometric ob-
servations, method of recording,

119

Battery, theory of, 279

BEarpD, T. M., ‘‘ Legal Responsibility
in Old Age” (review), 400

Beds of gypsum, 416

Beer, permanent, manufacture of, 280

BEHRENS, M., spectrum of the opal,
266

Begins, H., how to transform heat
into mechanical power, 418

Bei, Mr., advance of mechanical
puddling, 407

BELT, THOMAS, examination of the
theories that have been proposed
to account for the climate of the
Glacial period, 421

Beryls and emeralds, 504

Béton Aggloméré; or Coignet-Béton
and the Materials of which it is
Made”? (review), 112

Better communication in _ pit-
signalling by means of elec-
tricity, 262

‘ Birth of Chemistry ” (review), 251

Bismuth, hydrous arsenate of, 410

— metallurgy of, 408

— ore near Meymac, 406

Buackiey, C. H., ‘ Experimental
Research on the Causes and
Nature of Catarrhus Aéstivus
(Hay-Fever, or Hay-Asthma) ”
(review), 118

Blast-furnace slag, utilising, 264

— furnaces, consumption of coal in,
263

——new form of wagon drop for,
542 .

BLaAnForD, W. T., evidence of glacial
action in Tropical India, 127

Blocks, concrete, 269

“Body and Mind, the Theories of
their Relation’’ (review), 113

Boilers, 266

— report on, 267

— strength of, 125

BoTtTomLeEy, W., eclipsing apparatus
at Holywood lighthouse, 541

Bonney, T. G., ‘‘Geology”’ (review),

532
BRAMWELL, F. J., waste of fuel,

543
Bridges, long-span (review), 118
Brighton and Hove gas works, 268
British artillery matériel, recent
changes in, 40
Browy, R. G. S., ‘‘ Divine Revelation
or Pseudo-Science”’ (review),
Butvock, T.A.,‘* Animal Physiology ”’
(review), 257

INDEX.

‘ (October,

Burglar, fire, and other alarms, lec-
tures upon the system of, 133

Gries J. F., polar glacia-
tions, 414

CARON, new mode of tempering steel,
122

CASSELBERRY, result of experiments
with voltameters, 132

Cat’s-eyes, description of, 122

— examination of, 265

Cause of delay to the publication of
‘* Mineral Statistics,” 261

Channel tunnel, 272

Chandra, iron deposits of, 263

CHAPPELL, W., “The History of
Music” (review), 516

‘Chemical Analysis, Quantitative’
(review), Iu7

‘Chemistry, Birth of” (review), 251

**Chemistry, Elements of” (review),
252

Chemistry of minerals, 410

Chert and flint implements found in
Kent’s Cavern, near Torquay,
141

CHERVILLE, M., process for testing
the colour of wines, 280

China, coal-fields in, 120

Cuurcu, A. H., analysis of Ashantee
gold, 409

— — of clean grain gold from a burn
at Wanlock, 409

— beryls and emeralds, 504

— analysis of native silver, 410

Crapp, W. J., description of the coal-
cutting machine, 120

Coal and nickel ore in Persia, 406

— consumption of in our blast-
furnaces, 263

Coal-cutting by machinery, 262

— machine, description of, 120

— machinery in mines, working of,
II

Coal fields and mining industries of
Russia, 538

-— — in China, 120

— — of Italy, 538

— — of South Wales, 538

— — of Victoria, 538

— — — — report on, 262

— mechanical arrangements for ship-
ping, 543

— mining, 538

— produce of England, 119

Cockchafers for manure, 548

“ Coignet-Béton or Béton Aggloméré,
and the Materials of which it is
Made” (review), 112

Colliery accidents, prevention of, 119

— explosions, prevention of, 262

1874.|

Coloured tapers, 280

Comet, Coaara’s, 546

Comets’ tails, curved appearance of,
508

Composition of the natural com-
pounds of tantalium and niobium,
266

Concrete blocks, 269

Condition of silicon in pig-iron, 408

Conditions under which diamonds are
found, 263

‘Conservation of Energy ” (review),
232

Construction and maintenance of
Braye Bray Harbour, 123

Consumption of coal in our blast-
furnaces, 263

Contact theory of the battery, 279

Cooke, J. P., jun., mineralogical
paper, 409

Copper mines, native, of Lake Supe-
rior, 162

— ore in Anglesey, 120

“Correlation of Physical Forces”
(review), 524

Corundum, discovery of, 264

— study of, 265

Counterfeit wines, 280

‘Creation by Evolution, or Darwinism
and Design” (review), 229

Crookes, W., notes of an enquiry
into the phenomena called spirit-
ual, 77

Crystals of metallic antimony, artifi-
cial, 408

Cu.Ltey, R. S., ‘* Handbook of Tele-
graphy ” (review), 255

CUNNINGHAM, A., investigation of
determinants, 212

Cutting sections forthe microscope, 417

ALLINGER, W. H., life-history
of monads, 273

Danvers, F. C., annual international
exhibitions, 332

— — economy of fuel, 67

Davipson and Kina, Trimerellide,
415

Davies, T., ‘‘ Preparation and Mount-
ing Microscopic Objects” (review),
252

“ Darwinism and Design, or Creation
by Evolution ” (review), 229

Davy lamp, method of preventing
tampering with, 262

Deane, H., death of, 417

Deep sea sounding, 541

— — thermometer, 277

DENAYROUZE, M., ingenious apparatus
for the miner to obtain fresh air,
262

INDEX.

551

Deposits of iron ore in Mount Bis-
choff, 406

Deptford water supply, 267

Diatomaceen typenplatte, 546

Description of horbachite, 123

— of microsommite, 123

‘Description of Practical Solid Geo-
metry ”’ (review), 397

Description of stones called cat’s-
eyes, 122

‘Design and Darwinism, or Creation
by Evolution ”’ (review), 229

Designs for ships, 412

Determinants, investigation of, 212

Diamonds, conditions under which
found, 263

— in South Africa, 272

Diffracted and refracted spectra, rela-
tion between, 27

Discovery of corundum, 264

— of fossils, 271

Displacement of the method for ob-
taining voluntary returns, 261

Dispute about fine lines on test-plate,
131

Distribution of spathic iron ores,
406

‘‘Divine Revelation or Pseudo-Sci-
ence ”’ (review), 523

Double acetates, 137

Douctas, H., luminiferous ether and
atomic matter, 180

Douatas, J., native copper mines of
Lake Superior, 162

Drayson, Lieut-Col. A. W., Pole star
and the pointers, 285

—on the curved appearance of
comets’ tails, 508

Dublin water supply, 269

Dunn, E. J., conditions under which
diamonds are found, 263

| Daevns HQUAKE and volcanic erup-
tion at Nissiros, 127

Eclipsing apparatus at Holywood
Lighthouse, 541

EDGELL, A.W., discovery of fossils, 371

Epmunps, R., recent extraordinary
oscillations of the waters in Lake
Ontario, and on the sea-shores of
Peru, Australia, Devonshire, &c.,
156

Economical uses and production of
fuel, 194

Economy of fuel, 67

— of steam, 268

Effects of heat, 134

‘‘Elementary Treatise on Physics,
Experimental and Applied, for the
Use of Colleges and Schools”
(review), 117

552

Elasticity of metals, 264

‘*Elementary Treatise on Steam”
(review), 395

‘* Elements of Chemistry” (review),
252

Electric cable against fires, 419

Electrical vacuum tube, 279

‘ Electricity and Magnetism” (re-
view), I07

Eleétricity, better communication in
pit-signalling by means of, 262

Ele&tro-magnet whistle for locomo-
tives, 419

‘‘ Elements of Metallurgy ”’ (review).

535

Emeralds and beryls, 504

‘‘ Energy, Conservation of”’ (review),
232

‘“ Engineering,
IIo

English edition of ‘‘ Revue Universelle
des Mines,” 264

“English Psychology, Contemporary”
(review), 236

Epidote of Sulzbach, optical charac-
ters of the, 266

Ettringite, 411

Examination of cat’s eyes, 265

—of the theories that have been
proposed to account for the cli-
mate of the Glacial period, 421

Expansion of substances by heat,
418

“Experimental Enquiry into the Me-
chanical Properties of Steel”
(review), 398

‘«Experimental Research on _ the
Causes and Nature of Catarrhus
/Estivus (Hay-Fever or Hay-
Asthma) ” (review), 118

Experiments on Swedish steel, r21

— with voltameters, result of, 132

Explosion in collieries, prevention of,
262

Extension of railways between Bris-
tol and Redstock, 126

Sanitary’? (review),

“eye and Fruits Proper
Food of Man” (review), 239

Felspars, new species of, 265

Fire, burglar, and other alarms, lec-
tures upon the system of, 133

FiscHer, M., examination of cat’s
eyes, 265

‘Fish and Fisheries, United States
Commission ”’ (review), 405

FIsHBourNnE, Rear-Admiral, ‘ Our
Ironclads and Merchant Ships ”
(review), 396

FIsHBOURNE, Rear-Admiral, loss of
life at sea, 465

INDEX.

[Oétober,

FISHER, O., origin of the estuary of
the Fleet, 127

FLEMING, J. A., contac theory of
the battery, 279

Flint and chert implements found in
Kent’s Cavern, near Torquay,
I4I

FLower, W. H., new species of Ha-
litherium, 128

Fluorescent and absorption speétra of
the uranium salts, investigation
of, 133

Foresite, mineral, 540

Formula for glycerin jelly, 273

Fossil collection guide, 415

Foster, P. LE NEVE, jun., coal-fields
of Italy, 538

“ Fourth Annual Report of the Board
of Commissioners of Public Cha-
rities of the State of Pennsyl-
vania”’ (review), 532

Fox, C. B., ‘‘Ozone and Antozone;
their History and Origin” (re-
view), 116

Freezing microtome, 128

FritH, Mr., introduction of working
coal-cutting machinery in mines,
IIg

FroupbE, W., useful displacement of
weight, of structure, and of pro-
pulsive power, 412

“ Fruits and Farinacea, the Proper
Food of Man” (review), 239

Fuel, economy of, 67

— waste of, 541

ALLOWAY, W., method of re-
cording barometric and thermo-

metric observations, IIg

— — prevention of colliery accidents,
11g

GALL’s discovery of the physiology
of the brain, and its reception,
56

Galvanic current entering and leaving
a conducting medium, 279

Gas generator, improved forms of,
139

GeikigE, A., “ Geology ”
240

GEISSLER, M., electrical vacuum tube,

(review),

279
Geological block model of London,
12
_- cavendeetinn in the neighbourhood
of Hallstadt, 128
— record, 271
— Survey of the United Kingdom, 52
“ Geology ” (review), 240
Geology and parish boundaries, 371
— Professor of at Oxford, 546

1874.]

Geology of West Coast of Africa, 537

GenTH, F. A., study of corundum,
265

GiLtmorE, C. A., ‘‘ Béton Aggloméré,
or Coignet-Béton, and the Mate-
tials of which it is Made” (re-
view), II2

— — ‘' Practical Treatise on Limes,
Hydraulic Cements, and Mor-
tars’ (review), 112

Glacial action in Tropical India, 127

— period, theories to account for the
climate of, 421

Glaciation, polar, 414

Glycerin to prevent incrustations in
steam boilers, 419

Gopparp, T. M., better communica-
tion in pit-signalling by means of
electricity, 262

— — method of preventing tampering
with the Davy lamp, 262

Gold-fields of Victoria, 539

GoopvEVE, T. M., ‘‘ Principles of Me-
chanics”’ (review), 534

Gosss, P. H., ‘‘ Evenings at the Mi-
croscope ” (review), 254

Great Basses lighthouse, 270

Grochauite, new species of clino-
chlore, 410

Grove, Sir W. R.,
relation of Physical
(review), 524

Guns, 411

GuTHuRIE, F., galvanic current entering
and leaving aconducting medium,

279

AAS and ROHRIG, iron ores in
Bidasoa, 120

Habits of the “ plantain eaters,’’ 132

Hai_es, H. F., sand blast, 273

“*Half-Hours with the Microscope”
(review), 253

‘* Handbook of Natural Philosophy ”
(review), 531

‘* Handbook of Telegraphy” (review),
255

Halitherium, new species of, 128

“ Harveian Oration for 1874”’ (review),

22

‘‘Hay-Fever, Causes and Nature”
(review), 118

Haywoop, street pavements, 268

Heat, 274, 418

— effects of, 134

Helioscope, new, 546

HERSCHEL and G. A. LEsBouR, ex-
periments on the conduéting
power for heat of certain rocks,
127

“The Cor-
Forces ”’

INDEX.

553

Highlands, ancient volcanoes of, 271
‘History of Music” (review), 516
History of Rhine Valley, 415
Hot.tey, A. L., tests of metals, 264
Horbachite, description of, 123
HuGuHEs, T., iron deposits of Chandra,
in the Central Provinces, 263
Hunt, R., our tin trade and tin pro-
duétion, 539
‘““ Hydraulic Cements, Mortars, and
Limes, Practical Treatise on”
(review), 112

Pets and Iowa tornado, 339

Improved forms of gas generator,
139

Improvement in photo-lithography,
380

— of the water supply of Paris, 124

“Industry and Science, Annual Re-
cord of” (review), 111, 398

International exhibitions, annual, 332

Intervals between trains, 413

** Introduction to Organic Chemistry ”
(review), 250

Investigation of determinants, 212

— of the fluorescent and absorption
spectra of the uranium salts, 133

Iowa and Illinois tornado, 339

Iradescantia virginica, 567

Iron-deposits of Chandra, in
Central Provinces, 263

Iron, CramMpTon’s revolving furnace
for puddling, 539

— mines of Antrim, 537

— molecular changes produced in by
variations of temperature, 264

— ore, deposits of at Mount Bischoff,
406

— ores in Bidasoa, 170

— remarks on, 408

the

EANS, J. S., coal-cutting by ma-
chinery, 262
JENKIN, F., “ Eleatricity and Mag-
netism”’ (review), 107
Jenks, Col., discovery of corundum,
264.
Joun, W., strength of iron ships, 412
JORDAN, W. L., ‘‘ The Ocean” (re-
view), 246
Jupp, J. W., ancient volcanoes of the
Highlands, 271

Kee: G. H., peat bogs, 294

— water basin of Lough Derg, 127
Kina and Davipson, Trimerellide,

415

554

KitTon, F., ‘‘Half-Hours with the
Microscope ”’ (review), 253

Kein, C., optical characters of the
epidote of Sulzbach, 266

KirkaLpy,D.,experiments on Swedish
steel, 121

— ‘Experimental Enquiry into the
Mechanical Properties of Steel”
(review), 398

Kwnop, Dr., description of horbachite,
123

Know es, H., method of converting
cast-iron into malleable iron or
Steel, 122

| Wikio basins, origin of, 271

Larpn_er, D., ‘‘ Handbook of Natural
Philosophy ” (review), 531

LatuaM, B., ‘‘ Sanitary Engineering”
(review), 110

LAWRENCE, J., remarks on
408

Lesour, G. A., and HERSCHEL, ex-
periments on the conducting
power for heat of certain rocks,

iron,

12

e Leatires on Light” (review), 98

Lectures upon systems of fire,
burglar, and other alarms, 133

‘Legal Responsibility in Old Age”
(review), 400

LESPEYRES, artificial crystals of me-
tallic antimony, 408

Life-history of monads, 273

Life, loss of at sea, 465

Lighthouse, Great Basses, 270

“Light, Lectures on” (review), 98

‘‘ Light Science for Leisure Hours”
(review), 105

Lignites and American coals, age of,

06

a wie Hydraulic Cements, and
Mortars, Practical Treatise on”
(review), 112

List of projets for consideration at
the Private Bill Office, 126

Livingstonite, mineral, 540

Lockyer, J. N., ‘‘Spectroscope and
its Applications” (review), 102

Loess, description of, 126

Loewy, B., ‘‘ Handbook of Natural
Philosophy” (review), 531

“Long-Span Bridges” (review), 118

Luspock, Sir J., ‘‘ Origin and Meta-
morphoses of Inseéts” (review),
115

Luminiferous
matter, 180

“ Lunacy, Manual of’ (review), 250

ether and atomic

INDEX.

[Oétober,

Lunar atmosphere and its influence
on lunar questions, 492

Lurny, R., valves suitable for work-
ing hydraulic machinery, 542

Vea J., mechanical
arrangement for shipping, 543

MACFARLANE, J., coloured
280

Machinery, coal-cutting, 262

MackinTosH, J., Iowa and Illinois
tornado, 339

MACKENZIE, J., report on the coal
fields of Victoria, 262

Magic lantern slides for geology, 417

Magnetic ore separation, 539

‘Magnetism and Eledtricity” (re-
view), 107

Maintenance and construction of
Braye Bay harbour, 123

Manufacture of permanent beer, 280

“ Manual of Lunacy” (review), 250

Maunper, S., ‘* Treasury of Natural
History ” (review), 404

MarsHAtL, W., ‘ Phrenologist
Amongst the Todas” (review),
204

Mat, M. pe, alarum signals, 419

Matériel, British artillery, recent
changes in, 40

Mechanical puddling, advance of, 407

“ Medical Ele@ricity, Theoretical and
Practical, and its Uses in the
Treatment of Paralysis, Neuralgia,
and other Diseases’ (review), 117

Mep.uicott, H. B., Narbada, or
Satpura coal basin, 262

Memoir of the Caspian Sea, 127

‘Merchant Ships and Ironclads”
(review), 396

Metallurgy of bismuth, 408

Metals and minerals of
Burmah, 139

— elasticity of, 264

— tests of, 264

‘‘ Metamorphoses and Origin of In-
sects”’ (review), 115

Meteoric stone which fell at Barratta
Station, 123

Method of converting cast-iron into
malleable iron or steel, 122

— — preventing tampering with the
Davy lamp, 262

— — recording barometric and
thermometric observations, I19

Meyer, J.C.C., patent high-pressure
boilers, 125

“‘ Microscope, Evenings at” (review),
254

‘* Microscope, Haif-Hours with .the ”
(review), 253

tapers,

Upper .

1874.]

Milk, composition and analysis of
concentrated, 547

Mititer, W. A., ‘Elements’ of
Chemistry ” (review), 252

“Mind and Body: the Theories of
their Relation ” (review), 113

Mineral arsenides and_ sulphides,
123

— resources in Victoria, 406

—- species of felspars, new, 265

Mineral statistics, 263

— — cause of delay in the publication
of, 261

“ Mineralogy” (review), 533

Minerals and metals of Upper
Burmah, 139

Modern researches in tropical zo-
ology, 320

— steel, nature and uses of, 122

Mojsisovics, Dr. Von, geological
investigation of the neighbour-
hood of Hallstadt, 128

Molecular changes produced in iron
by variations of temperature, 264

Monograph of minerals, 265

MonTEiR0, J. J., habits of the ‘“ plan-
tain eaters,’ 132

Moon, past history of, 306

‘“ Mortars, Hydraulic Cements, and
Limes, Practical Treatise on”
(review), 112

Morton, C. H., condition of silicon
in pig-iron, 408

‘* Mounting and Preparation of Micro-
scopic Objects”’ (review), 252

Murezonsaurus, 415

N ARBADA, or Satpura coal basin,

262

Native copper mines of Lake Superior,
162

Natro-metallurgy, a process for re-
fining impure lead, 408

Natural compounds of tantalum and
niobium, 266

‘Natural History for Beginners”
(review), 248

‘Natural History, Treasury of” (re-
view), 404

Nature and uses of modern steel,
122

Navigation, steam, 541

Nerson, Epmunp, the lunar atmo-
sphere and its influence on lunar
questions, 492

Nefediewite, 123

NeELtHROpp, H. L., ‘Treatise on
Watch- Work ” (review), 259

NENDEL, G. W., guns, 411

Nrweserry, J. S., age of American
coals and lignites, 406

INDEX.

555

New alloy, 264

— Mexican mineral, 410

— mode of tempering steel, 122

— rock drill, 414

— safety-lamp, 120

NicHotson, H.A., ‘‘ Natural History
for Beginners” (review), 248

Nickel and coal in Persia, 406

Niobium and tantalum, the composi-
tion of the natural compounds of,
266

N6GGERATH, M., phosphorescent glow
of agates and other siliceous
stones, 266

— production of light in grinding hard
stones, 279

Note on tube boilers, 267

Notes of an enquiry into spiritualism,

77
Rasheed beaker aa of America, 274

Observations about brookite, 123

—on the optical phenomena of the
atmosphere, 34

“Old Age, Legal Responsibility in”
(review), 400

Otiver, S. P., recent changes in
British artillery matériel, 40

Opal, spectrum of, 266

Optical characters of the epidote of
Sulzbach, 266

— phenomena of the atmosphere, ob-
servations on, 34

“Organic Chemistry,
to’’ (review), 250

‘Origin and Metamorphoses of In-
sects”? (review), 115

Origin of lake basins, 271

— — the estuary of the Fleet, 127

“Our Ironclads and Merchant Ships ”’
(review), 396

‘* Ozone and Antozone ; their History
and Origin” (review), 116

Introduction

ADDON, J.B., Brighton and Hove
gas-works, 268 j

Paleontology, 271, 415, 545

PauL, M., improvement in photo-
lithography, 280

Parish boundaries and geology, 271

Past history of our moon, 306

PasTEuR, M., manufacture of per-
manent beer, 280

PayEN and Roux, MM., natro-
metallurgy, a process for refining
impure lead, 408

Peat-bogs, 294

PENGELLY, W., flint and chert im-
plements found in Kent’s Cavern,
near Torquay, 141

556

Pernot, M., puddling furnace, 407

Perry, J., ‘‘ Elementary Treatise on
Steam ” (review), 395

Peruviar. mineral, huantajayite, 410

PETTIGREW, J. B., ‘‘ Animal Loco-
motion ” (review), 237

Pes.in, M., elasticity of metals, 264

PHILLIPS, late Prof., 416

— T.A., ‘‘ Elements of Metallurgy ”
(review). 534

Phosphor bronze, 121

Phosphoreséent glow of agates and
other siliceous stones, 266

Photo-lithography, improvement in,
280

‘* Phrenologist amongst the Todas”
(review), 240

‘‘ Physics, Experimental and Applied,
for the Use of Schools and Col-
leges’’ (review), I17

‘‘ Physiology, Animal” (review), 257

Physiology of the brain, and its recep-
tion, 56

Pierce, W. T., ‘‘ Practical Solid or
Descriptive Geometry ”’ (review),
39

Bisica condition of silicon in, 408

PirscuH-Baupoin, M., new alloy, 264

Pit-signalling, better communication
in by means of eledtricity, 262

‘“* PLATTNER’S Manual of Qualitative
and Quantitative Analysis with
the Blowpipe”’ (review), 531

Polar glaciation, 414

Pole star and the pointers, 285

PonrTon, M.,relation between refracted
and diffracted spectra, 27

“‘ Practical Solid or Descriptive Geo-
metry ”’ (review), 397

“Practical Treatise on Limes, Hy-
draulic Cements, and Mortars”
(review), 112

Prazmowski, M., new helioscope, 545

‘‘ Preparation and Mounting of Micro-
scopic Objects”’ (review), 252

Preparations in balsam, 273

Prevention of colliery accidents, 119

— — — explosions, 262

PRIDEAUX, T. S., on Gall’s discovery
of the physiology of the brain,
and its reception, 56

‘Principles of Mechanics” (review),

534

Process for testing the colour of wines,
280

Proctor, R. A., ‘‘ Light Science for
Leisure Hours” (review), 105

— past history of our moon, 306

— Saturnian system, I

—‘ The Universe and the Coming
Transits’ (review), 528

INDEX.

‘October,

Produ@tion and economical uses of
fuel, 194
—of light in grinding hard stones,

279

‘* Proper Food of Man: Fruits and
Farinacea”’ (review), 239

Proposed Channel tunnel, 272

Pseudomorphs, two kinds after rock-
salt, 410

“Psychology, English Contemporary”
(review), 236

Puddling furnace, 407

— mechanical, advance of, 407

UANTITATIVE Chemical
Analysis” (review), 107
Quantity and value of minerals, sum-
mary of, 261

Reese accidents, 413, 541

— between Wiveliscombe and Barn-
staple, 126

— fixed signals, 414

RAMMELSBERG, M.,
minerals, 410

—composition of the natural com-
pounds of tantalum and niobium,
266

— mineral arsenides and sulphides,123

Rapier, N.C., rail-vay fixed signals, 414

Rare mineral, roselite, 266

Ramszy, Mr., Rhine Valley, 415

RaTH, study of asmanite, 265

Recent changes in British artillery
matériel, 40

— extraordinary oscillations of the
waters on Lake Ontario and on
the sea-shores of Peru, Australia,
Devonshire, &c., 156

Reception and physiology of the brain
by Gall, 56

“Record of Science and Industry”
(review), 398

Refracted and diffracted spedtra, rela-
tion between, 27

Remarks on iron, 408

Report on boilers, 267

— — the coal-fields of Victoria,
262

Researches on alloys, especially those
of copper and tin, 121

Results of analysis, 410

REYNOLDS, O., electricity, 278

Rhagite, a hydrous arsenate of bis-
muth, 410

Rheims, improvement of the sewage,

chemistry of

124
Rhine Valley, history of, 415

Rizot, T., ‘‘Contemporafy English
Psychology ” (review), ay

1874.)

Ricue, A., researches on_ alloys,
especially those of copper and tin,
I2I

RicHTER, Prof. Tu., ‘* PLATTNER’S
Manual of Qualitative and Quan-
titative Analysis with the Blow-
pipe ” (review), 531

RICHTHOFEN, Baron von, coal-fields
in China, 120

— description of ‘‘ loess,”’ 126

Rivotite, mineral, 540

Rock drilling, 414

RopwELt, G. F., ‘* Birth of Chemis-
try’ (review). 251

Rouric, Dr.. and Mr. HaAas,
ores in Bidasoa, 120

Roux and Payen, natro-metallurgy,

iron

a process for refining impure
lead, 408
RUTHERFORD, W., freezing microtome,
128
RuTLEY, F., ‘“‘ Mineralogy ”’ (review),
533
AELTZER, A., “ Treatise on
Acoustics in Connection with

Ventilation, and an Account
of the Modern and Ancient
Methods of Heating and Ven-
tilation ” (review), 118
Sand blast, 273
“Sanitary Engineering”
IIo
Satpura, or Narbada coal basin, 262
SCHEELE’S green, unhealthiness of
rooms prepared with, 281
ScuHraurF, Dr., monograph of minerals,
205
— observations about Brookite, 123
SCHUNGEL, Dr., on sound, 280
“Science and Art, Year-Book of
Facts in” (review), 403
“Science and Industry, Annual Re-
cord of” (review), III, 398
‘‘Science, Light, for Leisure Hours ”
(review), 105
Scott, R. H., method of recording
barometric and thermometric ob-
servations, I1g
Sea, loss of life at, 465
Sections, naphthalin for cutting, 130
SEELEY, murzousaurus, discovery of,
AI5
Sewage, improvement at Rheims, 124
SHELLEY, C. P. B., ‘Workshop Ap-
pliances ”’ (review), tog
Ships, 412
— designs for, 412
Siberia, Steppes of, 545
Signals, 412
Silicon in pig-iron, 407
VOL. IV. (N.S.)

(review),

INDEX.

boy

Siliceous stones and agates, phos-
phorescent glow shown by, 266

Simpson, J. B., coal-fields and mining
industries of Russia, 538

SINGERLY, B., ‘Fourth Annual Re-
port of the Board of Com-
missioners of Public Charities
of the State of Pennsylvania”
(review), 532

Slag for blast-furnace, utilising, 264

Slide, new syphon, 567

SmiTH, C., distribution of spathic
iron ores, 406

— J., ‘‘ Fruits and Farinacea Proper
Food of Man” (review), 239

Smytu, R. B., mineral resources in
Victoria, 406

— J., Upper Bann, 541

SNELUS, G. J., spiegeleisen, 407

SOKOLNICKI, Count, counterfeit wines,
280

Sound, source and velocity of, 280

Spathic iron ores, distribution of, 406

Specimen of glass trom the American
sand-blast, 130

Spectra, refracted and diffracted, re-
lation between, 27

“ Spectroscope and its Applications”
(review), 102

Spectrum of the opal, 266

SPENCE, P., steam economy, 268

Spiegeleisen, 407

Spiritualism,notes ofan inquiry into,77

St. Criarr, G., “Darwinism and De-
sign; or Creation by Evolu-
tion” (review), 22

Statistics in connection with the coal
produce of England, 119

— mineral, 263

Steam economy, 268

— navigation, 541

“Steam, Elementary Treatise on”
(review), 395

“Steel, Enquiry into the Mechanical
Properties of” (review), 398

STELYNER, A., mineralogy, 409

STEVENS, A. J., application of com-
pressed air to underground
haulage, 120

STEWART, B., “ Conservation of
Energy ”’ (review), 232

Stoticzka, F., death of, 546

Street pavements, 268

Strength of boilers, 125

— of iron ships, 412

StTrovER, G. A., metals and minerals
of Upper Burmah, 139

** Students’ Animal Physiology” (re-
view), 257

Study of asmanite, 265

— of corundum, 265

558

Sub-Wealden exploration, 127, 272,

415,545
Sulzbach, epidote of optical characters
of the, 266
Summary of quantity and value of
minerals of the United Kingdom
during 1872, 261
Survey, Geological,
Kingdom, 52
Syngenite, description of, 266
System, Saturnian, 1

of the United

ANTALUM and niobium, the
composition of the natural com-
pounds of, 266
Tapers, coloured, 280
«* Telegraphy, Handbook of” (review),
255
cpr ature, variations in molecular
changes produced in iron, 264
Tempering steel, new mode of, 122
Tests of metals, 264
Thanet sand on the northern outcrop
of the London basin, 128
“The Ocean” (review), 246
‘““ Theory of Arches” (review), 531
Thermometric and barometric obser-

vations, method of recording,
11g

THOMPSON, JAMES, Prof., steam navi-
gation, 541

THoMsOoN, WM., Sir, deep-sea sound-
ing, 541

THORPE, Ab dae Quantitative Che-
mical Analysis” (review), 107
Tuurston, R. H., molecular changes
produced in iron by variations of
temperature, 264

Tietze coal and nickel ore in Persia,
406

Tin trade and tin produétion, 539

TopLtey, Mr., Geology and parish
boundaries, 271

Torbenite, 123

Trains, intervals between, 413

“« Transactions of the American Insti-

tute of Mining Engineers” (re-
view), 407

“Treasury of Natural History” (re-
view), 404

“Treatise on Watch-Work” (re-

view), 259

Trimerellida, 415

Tropical Zoology, modern researches
in, 320

Tube-boilers, note on, 267

TyNpDALL, J., ‘‘ Lectures on Light”
(review), 98

NHEALTHINESS of rooms
papered with Scheele’s green, 281

INDEX.

‘October,

United Kingdom, Geological Survey
of, 52

** Unitéd States Commission on Fish
and Fisheries’ (review), 405

‘* Universe and the Coming Transits”
(review), 528

Uranic acetate (normal), 135

Useful displacement as limited by
weight of structure and of pro-
pulsive power, 412

Utilising blast-furnace slag, 264

bY ape t vadae n= A., metallurgy
of bismuth, 408

Value and quantity of minerals, sum-
mary of, 261

Valves suitable for working hydraulic
machinery, 542

Veszelite, mineral, 540

Victoria coal-fields, 538

— — report on, 262

— gold-fields of, 539

Volcanic eruption and earthquake at
Nissiros, 127

Voltameters, result of experiments
with, 132

ieee drop, new form of, for
blast-furnaces, 543

Warp. J. C., origin of lake basins,
271

“ Watch-work ”’ (review), 259

Water-basin of Lough Derg, 127

Water supply, improvement of Paris,
124

— — of Deptford, 267

— — of Dublin, 269

Wax, Japan, 248

Wess, W., dispute about fine lines
on Nobert’s test-plate, 131

Wessky, M., Grochauite,new species
of clinochlore, 410

Weight of structure and of propulsive
power, useful displacement as
limited by, 412

West, Cuas., ‘* The Harveian Oration
for 1874’ (review), 522

Whistle for locomotives wrought by
electro-magnet, 419

Wuiraker, W., discovery of Thanet
sand on the northern outcrop of
the London basin, 128

— — geological block model of Lon-
don, 127

— —lists of papers on Geology,
Mineralogy, and Palzontology,
271

Se counterfeit, 280

— process for testing the colour of, 280

1874.]

Winstow, L. S., ‘“ Manual of Lu-
nacy ” (review), 250

Woop, Mr., utilising blast-furnace
slag, 264

Woopward, C. J., improved forms of
gas generator, 139

— H., Paleontology, 371

Working coal-cutting machinery in

mines, 11g
‘*Workshop Appliances” (review),
10g

INDEX.

559

WricGuHTson, T., new form of wagon
drop for blast-furnaces, 543

WirzBurRGER, P., Geology of West
Coast iron districts, 537

EAR-BOOK of Faéts in Science
and Art” (review), 403

Y fasaaurion sn M., description
of syngenite, 266

LIST OF PLATES AND WOODCUTS IN VOLUME IV. (N.S.)

Optical Phenomena of the Atmosphere .

New Freezing Microtome (2 figures)

Spectrum of Feathers of the ‘‘ Plantain Eaters 2
Fluorescent and Absorption Spectra of the Uranium Salts (9 figures)

Vessel for Extraction of Sulphur

Improved Forms of Gas Generator (2 figures) .

The Native Copper of Lake Superior
Deep Sea Thermometer .

The Pole Star and the Pointers (6 figures)

Peat Bogs

The Iowa and Illinois Tornado (24 figures)

Loss of Life at Sea (3 figures).
Curved Appearance of Comets’ Tails

PAGE
: : - c C 3 37

: : ; EZO
132
135
139
140
I4t
277
287
2098
339
5 : : ‘ 7 465
‘ : “ ~ |) 508

ERRATA.

Page 378, line 1, read ‘motions of the upper currents and of the heavy

masses.”’

Page 383, line 17 from bottom, read “It was at this point within 1} miles
of Iowa River, the course of which is here nearly parallel with that of the

tornado. The crookedness,” &c.

Page 394, line 13, for ‘Smithsonian Institute of Weseaw and Illinois,” read
‘* Smithsonian Institute, Warsaw, Illinois.”

CONTENTS: OF No. XLIV.

I; An Examination of the Theories that have been Proposed
to Account for the Climate of the Glacial Period.

II. Loss of Life at Sea.

III. The Lunar Atmosphere and its Influence on Lunar —
Questions.

IV. Beryls and Emeralds.
V. On the Curved Appearance of Comets’ Tails.

*
NOTICES OF SCIENTIFIC WORKS.

Chappell’s ‘* History of Music.”

West’s ‘The Harveian Oration for 1874.”

Brown’s *‘ Divine Revelation, or Pseudo-Science ?”

Grove’s “‘ The Correlation of Physical Forces.”

Proétor’s ‘The Universe and the Coming Transits.”

Lardner’s “*‘ Handbook of Natural Philosophy.” ;

Richter’s “‘ Plattner’s Manual of Qualitative and Quantitative Analysis”
with the Blowpipe.”

Allan’s ‘*‘ Theory of Arches.”

Bonney’s “‘ Geology.”

‘Fourth Annual Report of the Board of Commissioners of Public
Charities of the State of Pennsylvania.”

Rutley’s ‘* Mineralogy.” 2

Goodeve’s ‘‘ Principles of Mechanics.”

Phillips’s ‘‘ Elements of Metallurgy.”

Girard’s ** Le Monde Microscopique des Eaux.”

PROGRESS IN SCIENCE,

(Including the Proceedings of Learned Societies at Home and Abroad, and =F
Notices of Recent Scientific Literature), mee’

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