PBOCEE DINGS

OP TEE

MANCHESTER

LITERARY AND PHILOSOPHICAL SOCIETY.

YOL. XVIII.

Session 1878-79.

MANCHESTER:

PRINTED BY THOS. SOWLER AND CO., 24, CANNON STREET.
LONDON : BALLIERE, 219, REGENT STREET.

1879.

NOTE.

The object which, the Society have in view in publishing their
Proceedings is to give an immediate and succinct account of the
scientific and other business transacted at their meetings to the
members and the general public. The various communications
are supplied by the authors themselves, who are alone responsible
for the facts and reasonings contained therein.

INDEX.

Axon William E. A., M.E.S.L., F.S.S — The Poisonous Qualities of the
Yew, p. 67.

Baxendell Joseph, F.E.A.S.— Observations of Dr. Klein’s new Lunar
Crater near Hyginus, made at the Observatory, Birkdale, p. 96.
On the Meteorological Effects of the position of the Moon with
respect to the Sun, p. 99.

Bell Alfred, F.G.S The Area of the Middle Drifts as determined by

their Contents, p. 51.

Bevan E, J. — Note on Certain Thionates, p. 7.

Binney E. W., F.E.S., F.G.S. — On a Eucalyptus Globulous, p. 2. Ee-
marks on a Fossil Plant found at Laxey, in the Isle of Man, p. 19.
On Boulders of Clay from the Drift, p. 40. On an Old Letter of
Sir Walter Scott, p. 43. On a Gigantic Tooth of a Fossil Shark,

p. 118.

Bottomley James, B.A., D.Sc. — On a copy of the Principia of Newton,
p. 63. Colorimetric Experiments, Part II., p. 137.

Burghardt Charles A., Ph.D. — Mineralogical Notes, p. 111.

Dale E. S., B.A., and C. Schorlemmer, F.E S. — On the Combinations of
Aurin with Mineral Acids, p. 29. On Aurin, Part II., p. 88.

Grimshaw Harry, F.C.S. — On the Water of Thirlmere, p. 4. Note on
the Intensity of Moonlight, p. 39 On a further Analysis of the
Water of the Mineral Spring at Humphrey Head, p. 45.

Hannay J. B., F.E.S.E., F.C.S. — On Silicious Fossilization, Part II., p. 75.

Hartog Marcus M., F.L.S.— A Preliminary Abstract of an Investigation
of the Nervous System of Cyclops, p. 48.

VI

Heelis James. — Two Deductions from Mr. G. H. Darwin’s Letter in
Nature, Feb. 6, 1879, upon Sir W. Thomson’s Equation of Cooling,

v — Vo +

p X

'J 7T

4

kt

e

0

dz

p. 83.

Hurst H. A. — List of the Leguminosse of the Riviera collected by
Joseph Sidebotham, Esq., in the Winter of 1877-78, p, 133.

Ishimatsu Saduma. — On a Chemical Investigation of Japanese Lacquer,
or TJrushi, p. 52.

Mackereth Rev. Thomas, F.R.A.S., F.M.S. — On the Mean Temperatures
of the Winters of the last 29 years, p. 78,

Melvill J. Cosmo, F.L.S. — An Account of Three Visits to the Breidden
Hills, Montgomeryshire, North Wales, in May, June, and July,

1877, p. 26.

Nasmyth James, C.E., F.R.A.S. — Relative Brightness of the Planets
Venus and Mercury, p. 2,

Plant John, F.G.S. — The Great Sheatfish, Silums glanis, in Loch Bad-
a-Luacrudli, Ross, p. 107.

Planta Pv. — On the Grasses of Egypt, p. 134,

Poynting J. H., B.A., B.Sc. — On the Estimation of Small Excesses of
Weight by the Balance from the time of Vibration and the angu-
lar Deflection of the Beam, p. 33. Arrangement of a Tangent
Galvanometer for lecture-room purposes to illustrate the laws of
the action of currents on Magnets, and of the resistance of wires,
p. 85.

Rawson Robert, Assoc. I.N.A. — Screw Propulsion, p. 90.

Reynolds Professor Osborne, M.A., F.R.S. — On the Bursting of the Gun
on Board the Thunderer, p. 58

Rogers Thomas. — On Specimens of Ballast Plants collected at Cardiff in
September, 187 8, p, 71.

Stewart Professor Balfour, LL.D., F.R.S. — On a Modification of Bun-
sen’s Calorimeter, p. 66.

Waters Arthur Wm., F.G.S, — The use of the Opercula in the Determi-
nation of the Cheilostomatous Bryozoa, p. 8. On the Naples
Zoological Station, p. 128,

Wilde Henry.— -On some Improved Methods of Producing and Regula-
ting Electric Light, p. 12. On some Improved Methods of
Producing and Regulating Electric Light, Part II., p. 22.

Williamson Professor W. C., F.R.S.— On a Section of the Eucalyptus
G-lobulous, p. 94. On the Oval Scars on the Stems of the Carboni-
ferous genus Ulodendron, p. 94.

Meetings of the Physical and Mathematical Section.— Annual, p.
96. Ordinary, pp. 63, 78, 137.

Meetings of the Microscopical and Natural History Section.—
Annual, p. 130. Ordinary, pp. 25, 26, 48, 71, 106, 107.

Report of the Council.— April, 1879, p. 119.

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PROCEEDINGS

OF THE

LITEEAEY AND PHILOSOPHICAL SOCIETY.

General Meeting, October 1st, 1878.

J. P. Joule, D.C.L., LL.D., F.B.S., &c., President, in the

Chair.

Mr. James Ballantyne Hannay, F.RS.E., Assistant Lec-
turer on Chemistry in the Owens College; and Mr. John
Priestley, Demonstrator and Assistant Lecturer in Physio-
logy and Histology in the Owens College, were elected
Ordinary Members of the Society.

Ordinary Meeting, October 1st, 1878.

J. P. Joule, D.C.L., LL.D., F.RS., &c., President, in the

Chair.

Among the Donations announced was a portrait of Dr.
Percival, presented by Mr. Francis Nicholson, F.Z.S., Hono-
rary Librarian of the Society.

On the motion of Mr. C. Bailey, seconded by the Kev.
Wm. Gas kell, it was resolved That the cordial thanks of
the Society be given to Mr. Nicholson for his valuable
donation of a portrait of Dr. Percival, the first President of
the Society.

Proceedings — Lit. & Phid. Soo.— Vol. XVIII.— No. 1.— Session 1878-79.

2

Ordinary Meeting, October 15th, 1878.

J. P. Joule, D.C.L., LL.D., F.R.S., &c., President, in the

Chair.

Mr. Binney, F.R.S., F.G.S., said that at a meeting of
the Society held on the 1 4th day of November, 1876, he
gave an account of a Eucalyptus globulus growing in
his garden at Douglas in the Isle of Man. In that year
(1876) it had grown 7ft. Sin. in height. In the following
year 6ft. 8in., when it unfortunately lost its leading shoot
by accident. Up to the 7th of this month it had grown 6ft.
Thus in the three years it had reached 20ft. 4in. in height.
The tree was planted in a sheltered situation close to the
sea, and its foliage at the present time, notwithstanding the
recent severe gales, presents a most luxuriant appearance
and yields a pleasant odour. No manure has been supplied
to the roots, which have grown in a soil formed of the
debris of Manx schist.

“ Relative Brightness of the Planets Venus and Mercury,”
by James Nasmyth, C.E., F.R.A.S., Corresponding Member
of the Society.

On many occasions when observing Mercury and Venus
separately in full daylight, I have always been impressed
with the strikingly inferior brightness of Mercury as com-
pared with Venus; and as such a condition is the very
reverse of what might be expected by reason of Mercury
being so much nearer to the sun than Venus, I awaited
the rare event of a very close conjunction of these two
planets that occurred on the 26th and 27th of September
last. With the advantage of a perfectly clear sky I had

3

the two planets before me for several hours, so to speak, side
by side in the field of the telescope at the same time, thus
affording me a most perfect opportunity for making a com-
parison of their relative brightness. It is difficult to convey
in words an exact impression of the difference in the bright-
ness of such objects, but I may attempt to do so by stating
that Venus looked like clean silver while Mercury looked
like lead or zinc. Were I to indicate my impressions by
way of number I would say that Venus was fully twice as
bright as Mercury. So remarkable an inferiority in the
brightness of Mercury, notwithstanding his much greater
nearness to the sun, appears to me to indicate the existence
of some very special and peculiar condition of his surface
in respect to his capability of reflecting light, a condition
that may be due to the nature of his envelope, if such
exist, or of that of his surface, by which the fervid light of
the sun’s rays falling on him are in a great measure quenched
or absorbed so as to leave but a small residue to be reflected
from his surface. If this be so, it appears to me to be
reasonable to suppose that the absorption of so much light
must result in a vast increase in the heat of the surface of
Mercury beyond what would have been the case had Mer-
cury possessed the same surface conditions as Venus.
Whether in the progress of spectroscopic investigation we
shall ever be enabled to detect some evidence of metallic or
other vapours or gases clinging to or closely enveloping the
surface of Mercury that might in some respect account for
so remarkable an absorption of the sun’s light, we must be
content to await the acquirement of such evidence if it ever
be forthcoming. It appears to me, however, to be well to
raise such a question, so that our astronomical spectroscopists
may be on the outlook for some evidence of the cause of so
very remarkable a defective condition in the light-reflecting
power of Mercury to which I have thus endeavoured to
direct attention.

4

“On the Water of Thirlmere,” by Harry Grimshaw,
F.C.S., and Clifford Grimshaw.

The samples of water of which the following details are
given were taken by us on August 23rd, 1878, from what
may be termed the “ upper and lower lakes,” meaning, above
and below the narrow waist of the lake, where crossed by
the small bridge. The first taken was the “lower” sample,
which was obtained on the west side of the lake about
twenty yards below the bridge. The “ upper” sample was
taken about three quarters of a mile below the head of the
lake on the east side. The results of the two samples so
far as position affects them should therefore be sufficient to
show any possible divergency which could occur in the
quality of the water on that account. These two positions
are shown upon the sketch map accompanying the paper.

The two samples were analysed separately except as re-
gards the amounts of ammonia (determined August 28th),
for which equal parts of each sample were taken, as there
was not a sufficient quantity for separate analyses.

The following are the numbers obtained :

Free ammonia — half a litre of water distilled took T5 cc.
standard NH4C1.

Albumenoid ammonia — half a litre of water distilled took
3*0 cc. standard NH4C1.

Total hardness — 70 cc. water took 1 cc. standard soap solu-
tion.

Permanent hardness — 70 cc. water boiled 1 hour and made
up took 1 cc. soap. — (The ammonia analysis common to
both samples, hardness same in each).

Solid matter — 100 cc. lower sample gave 0*0045 grams resi-
due, which blackened on ignition and lost 0‘0025 gram.

Solid matter — 70 cc. upper sample gave 0*0022 grams resi-
due, which blackened a little on heating, not so much
as lower sample, and lost on ignition 0*0007 gram.

Chlorine — 25 cc. lower sample took (1st) 0*25 cc. (2nd) 0.25
cc. standard AgN03 ; 25 cc. upper sample took (1st)
0*15 cc. (2nd) 0*15 cc. standard AgNO .

5

The foregoing figures give the following tabulated
results : —

Grains per Gallon.

Lr. Sample. Up. Sample. Dr. Roscoe’s.

Total solid matter 315 ... 2 20 ... T45

Mineral matter 1 '40 ... 1 '50 ... —

Loss on ignition 1*75 ... 0*70 ... —

Total hardness 1*00 ... 1*00 ... 0'50

Permanent hardness 1*00 ... 1*00 ... 0'50

Chlorine 0*70 ... 0'42 ... 0’42

Nitrogen as nitrates and nitrites.. — ... — ... 0'0247

Free ammonia 0'0021 0'00

Albumenoid ammonia 0'0042 04)049

The “ ammonias” expressed in parts per million are 0'03 and
0'06 respectively; the chlorine equals 0*7 and 1*16 grains per
gallon of salt.

The water was very clear and sparkling, practically free
from sediment, and its reaction perfectly neutral to litmus.
There was no reaction for heavy metals, copper, lead, iron,
&c., although we observed that there ran in close to the top
of the lake a small stream of a very turbid milky appearance,
upon which is situated on the side of the hill towards Hel-
vellyn, a lead mine; which stream could be traced by its
colour for at least 20 yards into the clear water of the mere.
These mining operations we understand will of course be
completely done away with on proceeding with the water
scheme.

We may offer the following brief remarks upon the above
analysis of the water of Thirlmere. In the first place it is
evident that the water is one of the very purest description
found in nature, not being surpassed by that of any locality
in Great Britain of which analyses have been published.

As regards its use for manufacturing purposes it practi-
cally could not be improved. For drinking purposes
also it is perfectly free from anything which could be con-
sidered objectionable, of either an organic or mineral
nature, though we are not prepared to assert that a water
considered “solely” as to its suitability for this purpose

6

attains any particular advantage from having its amount
of lime salts lower than some 10 or so grains per gallon,
though doubtless it is better that this should be very small,
than that it should be excessive. To give a fuller indica-
tion of the quality of the water of Thirlmere, we have taken
the liberty of appending to our results, those obtained by
Dr. Roscoe from a sample of the same taken in February
of this year. Now it will be seen that there is a certain
difference between the results of these samples, more espe-
cially with regard to our “lower” one. On examination,
however, the difference will be seen to be one of “ degree”
only, and not of “kind,” and entirely confined to the
mineral, and in this case the least important items. It is
explained by the fact that the rain-fall some little while
before the taking of the respective samples had been very
different, the longest period of dryness perhaps which we
have had this year having occurred just before the taking
of those of the present paper. We should therefore expect
that the solid matters would be higher, and find them to be
so by about one and a half grains per gallon, the total in
either case being insignificant. It would perhaps not be
wide of the mark if we said that the analyses of Dr. Roscoe
and ourselves show the water at its best and its worst as
regards ordinary variation. This variation it will be seen
is not greater than may occur at the same time in different
parts of the lake, as shown by our upper and lower samples,
these analyses also indicating a slight gradual increase of
dissolved material as we approach the foot of the lake,
where the solvent action of the water upon its bed will
have accumulated and the fresh water received from the
tributaries is lowest in amount. This gradation of quality
will, of course, only be true of the lake under its present
natural conditions.

The variation of the organic constituents of the water at
the different dates is not so marked. From the behaviour
of the solid matter during ignition we should say that the
carbonaceous matter, of which there is a perceptible amount,
is almost entirely of a vegetable nature.

7

Ordinary Meeting, October 29th, 1878.

J. P. Joule, D.C.L., LL.D., F.R.S., &c., President, in the Chair.

“Note on certain Thionates,” by E. J. Bevan, Student in
the Owens College. Communicated by Professor H. E.
Roscoe, F.R.S., &c.

Thallium Triothionate. When thallium carbonate is
treated with an equivalent quantity of trithionic acid, pre-
pared by precipitating potassium tritbionate with tartaric
acid, and the aqueous solution so obtained evaporated over
strong sulphuric acid, thallium trithionate separates out in
long colourless needle-shaped crystals isomorphous with
those of the corresponding potassium salt. Thallium tri-
thionate decomposes slowly at the ordinary temperature,
quickly on heating, and is with difficulty prepared free from
sulphate. Analysis showed it to contain 08% of thallium,
whereas the formula K2S306 requires 67'95%.

Hypovanadic Dithionate. — If an aqueous solution of
barium dithionate be precipitated with the requisite quantity
of hypovanadic sulphate, and the blue filtrate from the
barium sulphate concentrated in a vacuum over strong
sulphuric acid, crystals of hypovanadic dithionate separate
out. If concentration be continued after the first appearance
of these crystals, decomposition takes place, sulphur dioxide
is set free, and hypovanadic sulphate remains. This easy
decomposition prevents hypovanadic dithionate being pre-
pared in the pure state.

Aniline Dithionate — This salt is obtained in beautiful
long needles, by the double decomposition of barium
dithionate with aniline sulphate. Aniline dithionate is
comparatively stable, its aqueous solution may be boiled
without decomposition, when the dry salt is cautiously
heated in a vacuous tube it sublimes, a portion, however,
undergoing decomposition. It is freely soluble in water
and alcohol; 100 c.c. of water at 16° dissolve 7’89 grms. of
the salt. Its alcoholic solution, treated with sodium
amalgam, yields aniline sulphite. Analysis showed this

Proceedings— Lit, & Phil. Soc,— Yol. XYIIL— No. 2.— Session 1878-9.

8

body to contain 18*60% of sulpliur, whilst (C6H3NH2)2
requires 18*40% S.

“The Use of the Opercula in the Determination of the
Cheilostomatous Bryozoa,” by Arthur Wm. Waters,
F.G.S.

In the determination of the Bryozoa various authors have
attached very different importance to the characters used,
but the form of the aperture has been recognised by all to
be of use. D’Orbigny rightly used this very largely, and
Hassall pointed out that it was much less varying than
many points. Busk of course mentions the form in most
cases, but Professor F. A. Smitt, the first authority on the
Bryozoa, has used it much more largely, and has based his
classification of the Lepralia and allied genera principally
upon the form of the aperture. Dr. Hincks also has re-
cently proposed a new classification in many points similar
to Smitt’s, in which the form of the aperture is largely made
the basis.

It seemed to me that as the shape ot the oral-aperture
can only indicate the form of the operculum, which closes
it, the opercula themselves might furnish more reliable in-
formation, and I therefore prepared a series from the
material I had available, and I find it may be even more
useful than I at all expected. Besides indicating the form
of the aperture, there are also many other characters shown,
so that in the first 35 examined and figured all have an
easily distinguishable operculum.

The operculum is closed by means of two muscles, which
in some cases, as Myriozoum truncatum, fig. 15 ; Lepralia
pertusa var., fig. 4 ; Lepralia arrogata, fig. 6, &c., &c., are
attached at the side, in some quite from the edge, in others,
as Cellepora, fig. 8, from a muscular boss on the rim ; but
in most of the Celleporidse, and some Lepralia, &c., the
muscular attachment is on the interior surface as in Lep-
ralia Cecilii, fig. 1 ; Cellepora, fig. 5, &c.

9

In many it would seem that the opercula move upon a
sort of hinge, as in Myriozoum truncatum, fig. 15 ; Lepralia
arrogata, fig. 6, and a large number figured. In others it
seems that a membrane attached at the proximal end retains
it in its place. The opercula of some are curved into a
saddle-shaped form, as Hetepora Couchii, fig. 22, Eschara
foliacea in stadium Eschara and Hemeschara, fig. 24, 25,
and these have a concave proximal edge.

In some the operculum consists of two separable layers,
and this apparently causes the peculiar light portion of a
part in Lepralia cucullata. In Tub ucell aria cereoides a
light oval patch is seen in the centre, and in section fig. 36
this is shown to be caused by the chitinous operculum being
double elsewhere ; in fact it is like a meniscus with a con-
cave stop in front. I have every reason to think there is no
membrane enclosing this oval space, but cannot speak with
certainty, as I have confined my attention to those points I
deemed useful in determination, though a complete study
of the structure of the opercula, generally, would no doubt
repay the trouble. Tubucellaria hirsuta is not double in
the same way, and has the long muscular bosses further
from the edge.

In a large number of the Bryozoa the old and young
zooecia are known to vary so much as not to be recognisable
as the same species if discovered separately, but the oper-
cula of both arn the same ; also the operculated aperture is
in many surrounded by an elevated peristome, in other
words, is deep down in the throat, so that the shape cannot
be seen on account of the projecting lips. In such a case
the examination of the operculum will reveal the true form.

The determination of the Celleporidse has seemed to be
an almost hopeless task, as the form of the colony varies
greatly, and the avicularia and other characters are difficult
to use, but I believe the opercula may assist very much to
bring this family out of its present confusion. In Cellepora

10

the outside cells are decumbent, while the central ones are
erect, so that often no similarity is apparent, but so far as
my examination goes the opercula of both stages are the
same.

The size seems to vary but little, and in a slide of 6 or 7
in many cases all would exactly correspond with the draw-
ing of the one figured, and in few cases was the variation
over a tenth of the size. I was also much surprised to find
how closely the measurements of these Naples specimens
corresponded with the sizes of the aperture as given by
Smitt in his description of the Northern forms.

Although only groups allied to Lepralia have now been
brought under examination, it is by no means in these
families only that the shape of the oral aperture is of
importance, as in nearly all genera it is specifically charac-
teristic as may be seen in Membranipora, Diachoris, Bugula,
Flustra, &c., and a little more attention to this would have
made the British Museum Catalogue of much more value,
and prevented uniting under one name as Lepralia spinifera
species with different shaped apertures, which it has since
been necessary to separate. There are also other points
which may be of use, as for instance I find in one Eschara
from Australia that the operculum has 7 teeth in front, the
central one the largest, and in Cellepora sardonica, fig. 27,
it is strange to find lines on the edge corresponding with
the minute teeth in the aperture.

I should propose to divide the opercula into (a) those
with a straight proximal edge 27, 28, 29, 30, 31, 34 ; (6)
those with a straight edge and a sinal projection 1, 2, 3, 4 ;
(c) those with a subtriangular proximal end 5, 6, 7, 8, 15 ;
(cl) those with a rounded proximal end 9, 10, 11, 12, 16; (e)
saddle shaped, mostly with a concave end 22, 23, 24, 25, 26;
(/) suboblong 17, 18, 19, 20.

That the opercula may be of the greatest use in specific
determination there is now no doubt, and thus intimate

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11

relationship will be indicated, but how far general classifi-
cation may be assisted must remain open until larger series
have been examined.

EXPLANATION OF PLATE.

Opercula of

1 Lepralia Cecilii, Aud.

2 ■ vulgaris, Moll.

3 pertusa, var.

4 — — , var.

5 Cellepora.

6 Lepralia arrogata, Waters.

7 linearis, Hass, var typica SmitJ.

8 Cellepora.

9 Lepralia errata.

10 Cellepora Hassallii, John.

11 verruculata, Smitt.

12 Cellepora.

13 Lepralia auriculata, Hass.

14 cucullata. Busk.

15 Myriozoum truncatum, Pall.

16 Lepralia.

17 Lepralia Pallasiana, Moll, var projecta, W.

IB coccinea, Abild.

19 Pallasiana, Moll.

20 lata. Busk. This is larger than most opercula of lata.

21 Eschara contorta, Busk.

22 Retepora Couchii, Hincks.

23 cellulosa, Jam.

24 Lepralia foliacea, stadium Hemeschara.

25 Eschara foliacea, Ell & Sol.

26 Lepralia reticulata, Macg. var ophidiana, W.

27 Cellepora sardonica. Waters.

28 Eschara verrucosa, Peach.

29 Lepralia ciliata, Pall.

30 Malusii, Aud.

31 bimucronata, Moll.

32 Brongniartii, Aud.

33 rectieulata, Macg. var inequalis, Waters.

34 G-attyae, Lands.

35 Tubucellaria hirsuta, Busk.

36 cereoides, Ell & Sol. (in section).

37 Ditto do.

All magnified 85 times.

12

“ On some Improved Methods of Producing and Regula-
ting Electric Light,” by Henry Wilde, Esq.

Among the manifold functions which the elementary
substance carbon performs in organic nature, not the least
important is that by which it becomes the great source of
artificial illumination, whether derived from oils, coal gas, or
from coke rendered incandescent by the action of powerful
electric currents. Since the time when Davy first produced
the voltaic arc, between two points of wood charcoal, through
which was transmitted the current from the great battery
of 2000 plates belonging to the Royal Institution, many ex-
periments have been made to determine the best kinds of
carbon for developing the electric light. The carbon which,
until recently, was most commonly employed for this pur-
pose, is obtained from the sides of gas retorts, where it ac-
cumulates in the form of coke during the destructive dis-
tillation of coal. The shells of coke from the retort are sawn
up into pencils from one quarter, to half an inch square,
and from six to nine inches in length. Although very good
results are obtained from carbon of this kind, it is a difficult
material to work on account of its hardness, and it some-
times contains impurities which interfere with its conduct-
ivity. It is also liable to fracture when suddenly heated by
the transmission of powerful electric currents. These defects
have led to the introduction in electric lighting of artificial
carbon, composed of powdered coke and lamp black, formed
into a paste with molasses and gum. This material is pressed
into cylindrical forms, and subjected for a given time to a
high temperature in a special furnace. The manufacture of
these carbon pencils has attained great perfection in the
hands of Carre of Paris, and they can be made into perfectly
straight and cylindrical forms of from two to sixteen milli-
metres in diameter, and half a metre in length

When the electric light is to be used for illumination, it
is necessary that it should be as continuous as other modes

13

of lighting. For this purpose nbt only should the current
be regular in its action, but the distance between the carbon
points must not alter, which necessitates the use of some
arrangement for bringing them nearer together in propor-
tion as they are consumed. Much ingenuity has been
displayed by electricians in solving this problem, and the
automatic contrivances invented by Staite,Duboscq, Foucault,
Serrin, and others, leave little to be desired in regard to the
steadiness of the light, when the regulators are in good
order, and in the hands of intelligent operators. All auto-
matic instruments, however, from the delicacy of their
mechanism, are liable to derangement, and their action is
not easily understood by persons not having a special
knowledge of their construction. To obviate the objection
to the use of such instruments by unskilled attendants, I
devised, a few years since, a regulator for use on H.M/s ships
of war, to be actuated by hand. In this arrangement the
carbons are made to approach and separate from each
other by means of a right and left handed screw connected
with the carbon holders. Each of the screws, with its car-
bon holder, can be actuated independently of the other, for
the purpose of adjusting the points of the carbons to the
proper focus of the optical apparatus used in connection
with it. The regulator, with its carbon points, is placed in
the focus of a dioptric lens, which parallelises the divergent
rays of light into a single beam of great intensity. The
lens with the regulator is pivoted horizontally and verti-
cally on the top of a short iron column, fixed on a
raised platform above the deck ; and the beam of light may
be projected upon any distant object within its range. This
special application of the electric light, however, as will be
seen, requires the frequent adjustment of the carbons by
the operator ; but as he is always required to be in attend-
ance to manipulate the projector, no inconvenience is expe-
rienced through the absence of the automatic arrangement.

14

This method of regulating the electric light has now been
in use in the Royal Navy for more than three years, and
has proved very satisfactory.

Simultaneously with the progress of improvements in the
mechanism for regulating the electric light, experiments
have been made with the object of dispensing with the
regulator altogether. The most recent, as well as the most
successful, of these attempts has been made by M. Jablochkoff,
a Russian inventor. In the specification of his letters
patent of 1877, he proposes to place the carbons side by
side (as had been previously proposed by Werderman in
1874), and to separate them by an insulating substance to
be consumed along with the carbon. The inventor states
that the insulating substance for separating the carbons
may be kaolin, glass of various kinds, alkaline earths, and
silicates, which he prefers to apply in the form of powder
rammed into an asbestos cartridge case containing the
carbons. A powder which the inventor found serviceable,
consists of one part lime, four parts sand, and two parts
talc. These materials are rammed into the cartridge case
surrounding and separating two parallel sticks of carbon
placed in the case, at a little distance apart. One of the
carbons is made thicker than the other to allow for its more
rapid waste. The lower ends of the carbons are inserted
into pieces of copper tube or other good conductor, separated
from one another by asbestos, and the ends of the tubes
are pinched between two limbs of a screw vice, connected
respectively to the conducting wires. This combina/tion of
carbons and insulating materials the inventor terms an
electric candle, which, when mounted on a stand or candle-
stick, has the appearance of the Roman candle of pyro-
technists. The inventor further states that the heat pro-
duced by the electricity fuses the material between the
carbons and dissipates it ; and the freedom of the passage
afforded by the fused material to the electric current per-

15

mits the subdivision of the light by placing several lamps
in the course of one electric circuit. It is also stated that
the construction of the candle may be varied ; and, among
the forms described, is one in which the carbons, instead of
being contained in a cartridge case, are separated by a par-
tition of kaolin or other similar insulating material.

I have thought it well to describe, as nearly as possible
in the words of the inventor, the electric candle, which is
now the subject of so much attention in its application to
electric lighting ; so that its relation to what follows may be
more clearly perceived. A remarkable peculiarity of the
direct current in electric lighting is that of its consuming
the positive carbon at twice the rate of the negative one,
and while the negative carbon is a pointed cone, like that of
a pencil, the positive pole takes the form of a hollow cavity
or crater.

M. Jablochkoff’s early experiments seem to have been
made with the direct current, and hence his carbons are
described as being of unequal thickness in order that the
positive and negative carbons of the candle might be evenly
consumed. When the alternating current is used for pro-
ducing electric light both carbons are of the same thickness,
and are consumed at an equal rate, and both points termi-
nate in regular cones. This property of the alternating
current, besides other advantages, always maintains the
luminous point in the focus of any optical apparatus used
in connection with it, that is, when the carbons are placed
end to end, as I had occasion to point out in a former paper
read before the Society in 1873, on an Electro Magnetic
Induction Machine for producing alternating currents.

M. Jabloclikoff, in the course of his experiments, would
appear to have met with some difficulties in adapting the
direct or continuous current to a system of lighting with
his electric candles, and now uses the alternating current
for this purpose. The candle has also been simplified by

16

substituting a slip of plaster of Paris for the cartridge and
partition of kaolin formerly employed.

To produce the alternating currents, however, to supply a
number of lights, it was found necessary to employ power-
ful electro magnetic induction machines, excited by the
currents from other smaller machines, according to the
principles laid down in my paper read before the Royal
Society, and published in the Philosophical Transactions of
1867. From 16 to 20 lights are produced from one of these
electro magnetic machines, each light absorbing about one
horse power.

The system of electric lighting above described would
now seem to be definitely established in some places as a
substitute for gas, and visitors to the French capital during
the present summer, will have been struck with the fine
effects produced in the avenues and squares where the light
is displayed.

My connection with the history of this system of lighting,
placed me in a position to make some experiments with the
Jablochkoff candle, and led to the discovery of the following
facts. One of the conditions necessary for producing a con-
stant light from the candle, in its most recent form, was
that the quantity and intensity of the alternating current
should be such, that the carbons consume at a rate of from
four to five inches per hour. If the electric current were
too powerful, the carbons became unduly heated, and pre-
sented additional resistance to the passage of the current; the
points at the same time lost their regular conical form. If,
on the other hand, the current were too weak, the electric
arc played about the points of the carbons in an irregular
manner, and the light was easily extinguished by currents
of air.

In the course of these experiments I was struck with the
apparently insignificant part which the insulating material
played in the maintenance of the light between the carbon

17

points ; and it occurred to me to try the effect of covering
each of the carbons with a thin coating of hydrate of lime,
and mounting them parallel to each other in separate hol-
ders, and without any insulating material between them.
The use of the lime covering was intended to prevent the
light from travelling down the contiguous sides of the car-
bons. On completing the electric circuit the light was
maintained between the two points, and the carbons were
consumed in the same regular manner as when the insula-
ting material had been placed between them.

Two plain cylindrical rods of carbon three sixteenths of
an inch in diameter, and eight inches long, were now fixed
in the holders parallel to each other, and one eighth of an
inch apart. The strength of the alternating current was
such that it would fuse an iron wire 0 025 of an inch
in diameter and eight feet in length. On establishing the
electric current through the points of the carbons by means
of a conducting paste composed of carbon and gum, the
light was produced, and the carbons burnt steadily down-
wards as before.

Four pairs of naked carbons mounted in this manner
were next placed in series in the circuit of a four-light
machine, and the light was produced from these carbons
simultaneously, as when the insulating material was used
between them. The light from the naked carbons was also
more regular than that from the insulated ones, as the plaster
of Paris insulation did not always consume at the same
rate as the carbons, and thereby obstructed the passage of
the current. This was evident from the rosy tinge of the
light produced by the volatilisation of the calcium simul-
taneously with the diminution of the brilliancy of the light
from the carbons.

The only function, therefore, which the insulating mate-
rial performs in the electric candle, as shown by these
experiments, is that it conceals the singular and beautiful

18

property of the alternating current to which I have directed
attention.

As I have already said, the strength of the alternating
current must hear a proper proportion to the diameter of
the carbons used, and when a number of such lights are
required to be produced in the same circuit, the quantity
and property of the current will remain constant, while the
tension will require to be increased with the number of
lights.

This simple method of burning the carbons will, I believe,
greatly further the development of the electric light, as the
carbons can be used of much smaller diameter than has
hitherto been possible. They may also be of any desired
length, for as they are consumed they may be pushed
up through the holders without interrupting the light.
One of these developments will be a better method of
lighting coal and other mines. In this application the
alternating currents or waves from a powerful electro-
magnetic induction machine may be used for generating,
simultaneously, alternating secondary currents or waves in
a number of small induction coils, placed in various parts of
the mine. The light may be produced in the secondary
circuits from pairs of small carbons enclosed in a glass
vessel having a small aperture to permit the expansion of
the heated air within. Diaphragms of wire gauze may be
placed over the aperture to prevent the access of explosive
gas. By generating secondary currents or waves without
interrupting the continuity of the primary circuit, the con-
tact breaker is dispensed with, and the subdivision of the
light may be carried to a very great extent.

19

Ordinary Meeting, November 12th, 1878.

J. P. Joule, D.C.L., LL.D., F.R.S., &c., President, in the

Chair.

E. W. Binney, V.P., F.R.S., said that on the 22nd
January last he communicated to the Society a Notice of a
Fossil Plant found at Laxey, in the Isle of Man, which was
published immediately in the Proceedings. Now in Nature
of the 81st of October appears a letter from Dr. Dawson,
F.R.S., dated McGill College, Montreal, October 5, 1878, as
follows: “ A Fossil Plant — Misquotation. In an article on
a fossil plant from the Isle of Man in Nature, Yol. XVIII,
p. 555 (September, 1878), the following sentence is attribu-
ted apparently on the authority of Mr. Leo Lesquereux to
my Report on the Devonian and upper Silurian plants of
Canada ‘ that these fragments are probably originating in
the upper Silurian of Gaspe ; that as they are found in the
lower part of the limestone which underlies the Devonian
Gaspe sandstone and become more abundant in the upper
beds, this suffices to indicate the existence of the neighbour-
ing land probably composed of Silurian rocks and supporting
vegetation.’ On referring to the report in question I find
that the original of this strange statement stands as follows :

‘ These remains of Psilophyton occur in the lower part of the
limestone but are more abundant in the upper beds, and
they suffice to indicate the existence of neighbouring land
probably composed of lower Silurian rocks and supporting
Proceedings— Lit. & Phil. Soc.— Vol. XVIII.— No. 3.— Session 1878-9.

20

vegetation/ I have no doubt that Mr. Lesquereux quoted
from memory, and probably supposed that he was expressing
my meaning, but an English writer should have referred to
the original. I may add that the specimen referred to in Mr.
Binney’s article does not exhibit the characters of my genus
Psilophyton , which does not contain Mucoids’ but land plants
of the rank of acrogens and of which not merely the exter-
nal forms but also the internal structures are described and
figured in the report referred to. The plant in question
much more closely resembles Buthotrephis Harknessii of
Nicholson from the Skiddaw slates/5

With all due deference to Dr. Dawson I fail to see why I
should send to London in order to consult his original re-
port. Professor Lesquereux had sent me a copy of his (the
Professor’s) paper on Psilophytum cornutum published in
the Transactions of the American Philosophical Society.
This I received early in December, and immediately noticed
the great resemblance, if not identity, of his P. cornutum
with my Manx specimen. In noticing the latter I stated
that I should give his description at length, and I accord-
ingly gave it in inverted commas, word for word, including
the part Dr. Dawson complains of. Surely he cannot
seriously charge me with misquotation under such circum-
stances ! However, the Professor’s offence, if any, was pub-
lished in the Transactions of the American Philosopical
Society for November last year, I believe, and it appears the
Doctor does not set the public and himself right by commu-
nicating with that society, but, without a moment’s delay, in
October of this year, sends over to Nature his so-called mis-
quotation and its correction, adding that I “as an English
writer should have referred to the original.” Now as no

21

direct reference was made by me to the Doctor or any speci-
men of his Psilophyton , none of which resemble the fossil
plant described by me, I think he has no right to compel
me to read over all his learned and voluminous works how-
ever much he might think that I should be benefited by so
doing.

As to the Doctor’s opinion that my Manx plant resembles
the Buthotrephis Harknessii of Nicholson, all I can say is
that I have carefully compared the two figures of the speci-
mens— Dr. Nicholson having kindly sent me a copy of his
paper published in the Geological Magazine for November,
18G9 — and I see no reason to change my views. My Manx
plant is without question the most like Professor Lesquer-
eux’s figured specimen of Psilophytum cornutam, whatever
that plant may prove to be, of all the fossil plants that have
ever come under my notice. Any one may judge for him-
self by comparing the published figures of the specimens.

General Meeting, November 26th, 1878.

J. P. Joule, D.C.L., LL.D., F.RS., &c., President, in the

Chair.

Mr. Francis Jones, of the Manchester Grammar School;
Mr. Sidney Trice Martin, No. 1, George Street, Manchester;
Mr. Peter Phillips Bedson, D.Sc., Owens College ; and Mr.
Joseph Davies, Engineer, Manchester, were elected Ordinary
Members of the Society.

22

Ordinary Meeting, November 26th, 1878.

J. P. Joule, D.C.L., LL.D., F.R.S., &c., President, in the

Chair.

“On some Improved Methods of Producing and Regu-
lating Electric Light,” Part II., by Henry Wilde, Esq.

In a former communication to the Society, I directed
attention to the fact, that when the electric light is pro-
duced from the ends of two carbon pencils placed parallel
to each other, if the strength of the electric current, the
thickness of the carbons, and the distance between them
are rightly proportioned, the carbons will burn steadily
downwards until they are wholly consumed, without any
insulating material between them. To initiate the light by
this method, it is necessary to complete the electric circuit
between the carbons by means of some conducting sub-
stance, which volatilises on the passage of the current, and
establishes the electric arc between the points.

When a number of such lights are produced simulta-
neously from the same source of electricity, any interrup-
tion in the continuity of the current extinguishes all the
lights in the same circuit, and each pair of carbons requires
to be reprimed before the lights can again be established.
This defect, as will be obvious, would cause great inconve-
nience when the lights are not easily accessible, or are at
considerable distances apart.

In the course of my experiments it was observed that
when the electric circuit was completed at the bottom of a
pair of carbons close to the holders, the arc immediately

23

ascended to the points, where it remained so long as the
current was transmitted. My first impression of this pecu-
liar action of the arc was, that it was due to the ascending
current of hot air by which it was surrounded. This how-
ever was found not to be the cause, as the arc travelled
towards the points in whatever position the carbons were
placed, whether horizontally or vertically in an inverted
position. Moreover, when a pair of carbons were held in
the middle by the holders, the arc travelled upwards or
downwards towards the points, according as the circuit was
established above or below the holders. The action was in
fact recognised to be the same as that which determines the
propagation of an electric current through two rectilinear
and parallel conductors submerged in contact with the
terrestrial bed, which was described by me in the Philo-
sophical Magazine , August, 1868.

In all the arrangements in general use for regulating the
electric light, the carbon pencils are placed in the same
straight line, and end to end. When the light is required,
the ends are brought into momentary contact, and are then
separated a short distance to enable the arc to form between
them. The peculiar behaviour of the electric arc when the
carbons are placed parallel to each other, suggested to me
the means of lighting the carbons automatically, notwith-
standing the fact that they could only be made to approach
each other by a motion laterally, and to come into contact
at their adjacent sides. To accomplish this object, one of
the carbon holders is articulated or hinged to a small base
plate of cast iron, which is so constructed as to become an
electro-magnet when coiled with a few turns of insulated
wire. The carbon holder is made in the form of a riofit-

O

24

angled lever, to the short horizontal limb of which is fixed
an armature placed over the poles of the electro-magnet.
When the movable and fixed carbon holders are brought
into juxtaposition, and the carbons inserted in them, the
upper parts of the two carbons are always in contact when
no current is transmitted through them, as shown by the
dotted lines in the engraving.

The contact between the carbons is maintained by means
of an antagonistic spring inserted in a recess in one of the
poles of the electro-magnet, and reacting on the under side
of the armature. One extremity of the coil of the electro-
magnet is in metallic connection with the base of the carbon
holder, while the other extremity of the coil is in connec-
tion with the terminal screw at the base of the instrument,

25

from which it is insulated. The coils of the electro-magnet
are thus placed in the same circuit as the carbon pencils.

When the alternating current from an electro-magnetic
induction machine is transmitted through the carbons, the
electro-magnet attracts the armature and separates the
upper ends of the carbons, which brings them into their
normal position, and the light is immediately produced.
When the circuit is interrupted, the armature is released :
the upper ends of the carbons come into contact, and the
light is produced as before. When several pairs of carbons
are placed in the same circuit, they are, by this arrangement,
lighted simultaneously.

MICROSCOPICAL AND NATURAL HISTORY SECTION.
October 7th, 1878.

Charles Bailey, Esq., President of the Section, in the

Chair.

Professor W. C. Williamson, F.RS., made remarks on
a series of Lepidodendroid Macrospores from the Halifax
Coal Measures, as well as a series of reproductive crypto-
gamic conceptacles from the same measures, and also exhi-
bited some of these under the new Oil Immersion Lens of
Zeiss of Yena,

Mr. Plant exhibited a so-called Tree Onion from Canada.

26

November 4th, 1878.

Charles Bailey, Esq., President of the Section, in the

Chair.

Mr. Plant, F.G.S., exhibited as additions to the Fauna of
Cymmeran Bay, Anglesea, fine specimens of the Portuguese
Man of War (Physalia pelagica), which came in with a S.W.
gale, accompanied by many specimens of the Vellella.

Mr. J. Cosmo Melvill, F.L.S., read an account of three
visits paid by him to the Breidden Hills, Montgomeryshire,
North Wales, in May, June, and July, 1877.

The Breidden hills form an isolated range in the extreme
north-east corner of the county, where it joins Salop, about
ten or twelve miles due west of Shrewsbury, and three miles
distant from Welshpool, from which town the best view of
them is obtained, and where they are the most conspicuous
objects to the north-east.

The rocks are Lower Silurian, igneous and crystalline.
Moel-y-Golfa, the southernmost peak, attaining an altitude
of nearly 1500 feet, is formed of felspathic Trap and Ash;
while Craig Breidden, the northernmost summit, and the
intermediate hill, are both of Igneous Greenstone.

The county of Montgomery being one of the nine men-
tioned by Mr. Hewett C. Watson in his latest work —
“Topographical Botany” — as being completely unworked,
so far as Botanical data are concerned, renders any list of
the plants interesting. Among a total of over 800 observed,
the following catalogue represents the rarer species only :

Ranunculus parviflorus (L.)

Meconopsis Camhrica (Vig.)

Corydalis claviculata (D. L.)

Fumaria Borgei (Sm.)

27

Hesperis matronalis (L.)

Cheiranthus cheiri (L.)

Arabis — an hirsute varietas? — a form approaching A. arcuata
of Grenin and Godron, and A. alpestris (Gor.), both of the
flora of France — found sparingly by the waterfall, Craig
Breidden.

Teesdalia nudicaulis (Sm.)

Lychnis Viscaria (L.)

Moenchia erecta (Sm.)

Cerastium semidecandrum (L.)

Stellaria media (L.) var. neglecta.

Hypericum Androssemum (L.)

Geranium sanguineum (L.)

Geranium lucidum (L.)

Trifolium filiforme (L.)

Spiraea salicifolia (L.)

Potentilla rupestris (L.) On damp ledges in almost inaccessible
spots near the waterfall, Craig Breidden. The only British
station.

Sedum Telephium (L.)

Sedum anglicum (Hudson).

Sedum Forsterianum (Sm.)

Cotyledon umbilicus (L.)

Saxifraga granulata ( L. )

Saxifraga hypnoides (L.)

Helosciadium inundatum (Kosh.)

Heracleum sphondylium (L.) B. angustifolium.

Centranthus ruber (D. C.)

Doronicum Pardalianches (L.)

Centaurea montana (L.), naturalised near Welshpool.

Erigeron acris (L.)

Hieracium Pilosella (L.) B. pilosissimum, very hairy form with-
out stolons, confined to Craig Breidden and the Channel
Islands.

Hieracium lasiopl^dlum (Koch.)

Hieracium pallidum (Sm.) and its form maculatum.

Veronica hybrida (L.)

28

Veronica scutellata (L.)

Veronica raontana (L. )

Ajuga rep tans (L.) var. alba.

Euphorbia Lathyris (L.) nr. Criggion.

Ornithogalum umbellatum (L.)

Likewise the Laburnum — Cytisus Laburnum (L.) occurred in a
quasi-naturalized state on Moel-y-Golfa.

Among Ferns and Fern allies the only ones observed were :
Pteris aquilina (L.)

Asplenium Ruta muraria (L.)

Asplenium Trichomanes (L.)

Asplenium adiantum nigrum (L.)

Athyrium Filix. fcemina (Berch).

Lastrea Filix. Mas. (Aich).

Polypodium vulgare (L.)

Polypodium Dryopteris (L.)

Equisetum arvense (L.)

Pilularia globulifera (L. )

Mr. M. M. Haktog (who was present as a visitor) said
that when examining Desmids lately taken from a jar con-
taining Chara, he had discovered a decided nucleus in the
species known as Closterium aggregatum.

29

Ordinary Meeting, December 10th, 1878.

J. P. Joule, D.C.L., LL.D., F.R.S., President, in the Chair.

Among the Donations announced was a portrait of the
late Professor Eaton Hodgkinson, presented by Sir Thomas
Fairbairn, Bart.

On the motion of Mr. Binney, seconded by Dr. Schunck,
it was resolved unanimously : That the thanks of the
Society be given to Sir Thomas Fairbairn, Bart., for his
valuable Donation of a portrait of the late Professor Eaton
Hodgkinson.

“ On the Combinations of Aurin with Mineral Acids,” by
R. S. Dale, B.A., and C, Schorlemmer, F.RS.

In our last communication* we stated, that by the action
of acetyl chloride on aurin, we obtained a colourless crystal-
line compound, which we intended to examine more closely.
We have since found that this body is identical with a
compound, which Grabe and Caro~f° obtained by the direct
union of aurin and acetic anhydride and having the formula
C19Hl403+aH603.

We also mentioned that the purification of this substance
was found to be beset with several difficulties. The cause
of this was found out after some trouble, but at the same
time we were rewarded by the discovery of a series of re-
markable bodies, consisting of combinations of aurin with
mineral ^cids.

* Proc. Lit. and Phil. Soc. — 1878, 141.
t Ber. Deutsch. Chem. Ges. — xi., 1,122.

Proceedings— Lit. & Phil. Soc.— Yol. X YIII.— No. 4.— Session 1878-9.

30

These salts, as we may call them, are "beautiful bodies,
crystallizing exceedingly well, and although some of them
are decomposed by water, they are very stable in dry air.
To their discovery we were led by the following observa-
tions.

On heating aurin with glacial acetic acid and acetyl
chloride, tire crystals lose at once their steel-blue lustre and
assume a pale red colour. To obtain the compound thus
formed in a pure state, acetyl chloride was added to a satu-
rated solution of aurin in acetic acid. The liquid assumed
at once a much lighter colour, and soon pale red needle-
shaped crystals having a diamond lustre separated out. On
recrystallizing these repeatedly from alcohol, we obtained
oblong six-sided plates, which as analysis showed were pure
aurin.

On treating the original crystals with water, they become
dull and brownish red, the solution containing acetic and
hydrochloric acids. It therefore seemed not improbable that
an additive product of aurin and acetyl chloride had been
formed, containing however also acetic acid, as a superficial
examination showed, that the liquid contained, to one mole-
cule of hydrochloric acid, much more than one molecule of
acetic acid. We therefore tried to obtain an analogous
benzoyl -compound and to determine in it, after decompo-
sition with water the relative quantities of hydrochloric
and benzoic acids.

On adding benzoyl chloride to a hot solution of aurin in
acetic acid, similar crystals as before were obtained, which,
after being dried on filter paper in dry air, were decompo-
sed by water, but only hydrochloric and acetic acid went
into solution, and on heating the product with water or
alkalies but a mere trace of benzoic acid could be detected.

These facts, coupled with the observation that the bright
red needles which, as we stated in our former paper, are
formed by crystallising aurin from hot aqueous hydrochlo-

31

ric acid, retain the latter obstinately, led us to the con-
clusion that this acid forms a definite compound with aurin.

Such a body could be formed under the above conditions,
as our glacial acetic acid contained a little water. More-
over, Mr. Charles Lowe had informed us that the splendid
specimen of aurin which he exhibited at Paris was obtained
in the following way. The crude but crystalline aurin,
which is obtained by heating pure phenol with sulphuric
and oxalic acids, was dissolved in alcohol and some strong
hydrochloric acid added, by which a crystalline precipitate
was formed, crystallising from hot acetic acid in beautiful
red, glistening, flat needles. He was kind enough to give
us a sample, and on examining it we found that water
acted upon it in the same way as on our crystals.

In order to prepare a pure compound for analysis, a hot
solution of aurin in acetic acid was saturated with hydro-
chloric acid gas ; the colour of the liquid changed into a
light yellowish red, and soon the compound separated out
in glistening needles, which, even when perfectly dry, smell
strongly of acetic acid. When exposed to the air, they soon
assume a steel-blue lustre and gradually crumble into a
reddish brown crystalline powder. The same properties
are shown by the crystals obtained from acetyl chloride
and those obtained from Mr. Lowe. When heated to
110° in a current of dry air they gradually lose all the acetic
acid, which plays the part of water of crystallisation, and
assumes a dull red colour.

On passing hydrochloric acid gas into an alcoholic solu-
tion of aurin, similar but smaller needles are formed, con-
taining alcohol, which is given off at 100° ; the dull red
residue can, like the preceding one, be heated to 190° in a
current of dry air without losing hydrochloric acid, which
only begins to escape at 200°.

Analysis of these compounds showed that the dried sub-
stance consists of C19Hu03, HC1, while the crystals obtained

32

from an acetic acid solution have the composition C19H1403,
HC1+2C2H402, and those from alcohol 2C10H19O3, HC1
+ 3C2H60.

When sulphuric acid is added to a hot alcoholic solution
of aurin, small red needles are formed on cooling, which
consist of (Ci9H1403)2 S04H2-f Alcohol. Under the same con-
ditions an acetic acid solution yields fine prismatic crystals
or flat, very glistening needles, which are an acid sulphate,
its formula being Ci9Hi408, S04H2-f- Acetic acid.

We have also prepared a nitrate which is readily formed
and crystallizes well but have not analysed it yet.

In our first communication to the Chemical Society, we
described a compound of aurin and sulphur dioxide, which
is easily obtained in bright red crystals by passing sulphur
dioxide into a saturated alcoholic solution of aurin. Our
former observation that this body contains water, but no
alcohol, we found confirmed; on heating it decomposition
easily takes place, pure aurin being left behind, but it ap-
pears to be quite stable when exposed to the air, and even
on heating it with water no sulphur dioxide is given off,
but a drop of sulphuric acid added to the mixture is suffici-
ent to evolve the gas abundantly. Aurin sulphite has the
composition (Ci9H1403)2S03H2+4H20,

As we have already showed, aurin forms very character-
istic compounds with the acid sulphites of the alkali-metals,
which in accordance with the newly established formula of
aurin must now be written as follows :

c19h14o3, so3kh

C19H1403j S03NaH

C19Hl4035 S03(NH4)H

We have also found that rosolic acid, or the next higher
homologue of aurin forms compounds with mineral acids
which crystallize well. Being therefore a base like aurin,
we think its name ought to be altered and, as it has only
been obtained from rosaniline, propose for it the name

rosaurm.

33

“ On the Estimation of Small Excesses of Weight by the
Balance from the time of Vibration and the angular Deflec-
tion of the Beam/’ by J. H. Poynting, B.A.; B.Sc.

While working last year on an experiment to determine
the mean Density of the Earth by the balance, I had to
measure such an exceedingly small difference of weight,
that I could not at that time estimate it by means of a rider
but was obliged to adopt the method described in this paper.
Stated generally it consists in treating the balance as a
pendulum. Knowing the nature of the pendulum (that is
its moment of inertia), and its time of vibration, we can
calculate what force acting at the end of one arm of the
beam will produce a given angular deflection. It is in. fact
an application to the common balance of the method which
has always been used with the torsion balance when it has
been necessary to calculate the forces measured in absolute
measure. I cannot find any record of a previous applica-
tion of the method, and as it might be of use in very delicate
weighings, or in verifying the small weights in a laboratory.
I have thought it worth while to give a full account of it.

When small quantities of the second order are neglected
and the oscillations are of the first order, it will easily be
found that the equation of motion of the beam of the balance
is

(MP + 2 Pa2) Q + (2P& + M glc)Q — ap (1)

9

where MI2 = moment of inertia of beam about central knife edge
M = mass of beam
a — half length of beam.

P = weight of either pan and the mass in it.

h — distance of line joining terminal knife edges below the cen-
tral knife edge.

h - distance of centre of gravity of beam below central knife
edge.

p = small excess in one pan.

34

0 = angular deflection in circular measure produced by p.

9 = gravity.

If 0 = 0 we have the position of equilibrium given by.

e = 2 MW* <2>

The semi-periodic time is

/MI2 + 2Pa2

,=V mV+Mgl ^

From equations (2) and (3) we can eliminate 2P/&-f- Mgh,
obtaining

M^P + 2Pa2 0

p = id— 35 (4)

M ag r w

From this expression it appears that if we know the
moment of inertia of the beam, its length, and the weight
at each end, we can find the excess p from the time of
vibration and deflection.

The results given in this paper were obtained with a
16-inch chemical balance by Oe idling. The exact length of
the half beam (a) measured by a dividing engine is 20*2484
centimetres.

To find the moment of inertia MI 2 of the beam — The
simplest way theoretically would appear to be this. Find
the times of vibration tx t2 and the deflections 0i 02 due to
the same excess p with two different loads Pi P2 in each
pan. Equating the values of p given for each by equation
(4) we have

MyP 4- 2 Pi (I 02h2
MyP + 2P2n2_ 0p22

An equation which will give M(/I2 in terms of known
quantities. But on trial it was found that a very small
proportional error in the observed time made a large error
in the value of Myl2, and the following method, that usually
adopted in magnetic observations was employed in prefer-
ence. A stirrup was suspended by a platinum wire and its

35

time of vibration (ti) against tlie force of torsion Qi) of the
wire was observed. The moment of inertia of the stirrup
being S we have

ti = 7T^S
fX

The time of vibration (ti) was then observed when a cylin-
drical brass bar of known moment of inertia B was inserted
in the stirrup. We now have

ti = 7T2(S + B)

The bar was then removed and the balance beam inserted
in its place, and the time of vibration (tf3) gives

ti = 7T2(S + MI2)

From these three equations eliminating S and fx we obtain

Mp_Bfe2-^)
iVJ~L “ / 2 / 2

Now Bg was calculated from the weight and dimensions
of the bar to be 6332.83 (in centimetres and grammes). The
observed times were tx = 3.6792// ; U = 4.495" ; tz-l.\ 483" ;
From these values we find

My I2 = 35651.6*

To measure 6. The angle of deflection was measured by
the number of divisions of the scale which the pointer
moved over. As the length of the pointer is 32T006 centi-
metres, while 20 divisions of the scale measure 2*5658
centimetres, a tenth of a division, in terms of which the
deflection was measured corresponds to an angle of 0’0003996.
The oscillations were observed from a distance of 6 or 8 feet
by a telescope. The resting point (i.e. the point where the
balance would be in equilibrium) was found in the usual
way by observing the three successive extremities of two
swings and taking the mean of the second and the

* To this a small correction should be added if the adjusting bob is not in
its lowest position. This amounts to 7.6 for each turn of the screw and may
therefore in general be neglected.

36

mean of the first and third. Five determinations of the
resting point were usually made with the excess to he
measured alternately added and removed. From these five,
three values of the deflection (n) due to the excess were
calculated in a manner which will be seen from the example
below.

The time of vibration.. — This was found from several
determinations of the time of ten oscillations. The method
will be seen from the example. No correction was needed
for the resistance of the air as long as the vibrations did
not exceed two divisions of the scale. When however they
were much more than that the time of vibration was found
to increase with the arc. As the time of vibration fre-
quently changes slightly, probably through variations of
temperature, it was usually observed before and after the
determination of the deflection (n) and the mean of the two
taken as the true time.

The following example of the determination of the value
of a centigramme rider by placing it half way along the
beam wifi sufficiently explain the details of the method.

TIME OF VIBRATION AT COMMENCEMENT,

POINTER APPARENTLY MOVING FROM POINTER APPARENTLY MOVING FROM
LEFT TO RIGHT. RIGHT TO LEFT.

No. of
Vibration.

Observed time
of passage of
pointer through
resting point.

No. of
Vibration.

Observed
time of
passage of
pointer
through
resting p’t.

Time of 10
Vibrations.

No. of
Vibration.

Observed time
of passage of
pointer through
resting point.

No. of
Vibration.

Observed
time of
passage of
pointer
through
resting p’t.

Time of 10
Vibrations.

0

llh 15' 36"

10

17' 43"

127

1

llh 15' 49"

11

17' 56"

127

2

16' 1"

12

18' 8"

127

3

16' 14"

13

18' 21"

127

4

16' 25"-5

14

18' 33"k5

127,

5

16'39"-5

15

18' 46"

126-5

6

16' 52"

16

18' 59"

127 j

7

17' 5"

17 1

19' ll"-5

126-5

Mean value of 10 vibrations..

1271

1

Mean value of 10 vibrations..

12675

Mean of means 126-875.
i, = 12-6875"

37

DETERMINATION OF DEFLECTION U.

Excess Weight.

Extremities

of

Oscillation.

RestingPoint.

Mean of prece-
ding and
succeeding
resting points.

Deflection
due to
Excess.

Added

109

96

]09

102.5

i

Removed

93

40

92

66.25

102.25

36

Added

|

152

53

150

102

66.75

35.25

Removed

80

55

79

67.25

102.5

35.25

Added

147

60

145

103

Mean value of n — 35.83.

TIME OF VIBRATION AT END.

POINTER APPARENTLY MOVING PROM , POINTER APPARENTLY MOVING FROM
LEFT TO RIGHT. | RIGHT TO LEFT.

No. of
Vibration.

Observed time
of passing of
pointer through
resting point.

No. of
j Vibration.

Observed
time of
passage of
pointer
through
resting p’t.

Time of 10
Vibrations.

i

No. 'of
Vibration.

Obstrved time
of passing of
pointer through
resting point.

t/5 Observed
§ 1 time of
.43 passage of
o g pointer
^ £ through
resting p’t.

Time of 10
Vibrations.

1

0

llli 26' 19"

10

28' 27"

I

128 1

1

26' 32-5"

11 28' 39"

126.5

2

26' 44"- 5

12

28' 53"

128-5

3

26' 58"

13 29' 5"

127

4

27' 10"

14

29' 18"

128

5

27' 23-5"

15 1 29' 30"-5

127

6

27' 35"-5

16

29' 44"

128-5

7

27' 49"

17 29' 56"-5

127-5

Mean value of 10 vibrations..

128-25

■

Mean value of 10 vibrations..

127

Mean of Means=:127-625.

^=12-7625.

— — — I

Remembering that one tenth of a division of the scale is
an angle of *0003996 in circular measure formula (4), ex-
pressed in milligrammes, becomes

11 i/2

p = -p 0-3996^-(Mc/I2 + 2 Pa2)

38

In our present example
n — 35-83

tz=h±h = 12-725"

Myl2== 35651
2Pa2 = 94704*
p = 5’ 724 milligrams.

The length of time occupied in this determination was
not quite a quarter of an hour.

The following table contains a series of results which I
have obtained of the weight of two centigramme riders, the
first of which was accidentally destroyed after the conclu-
sion of the 4th determination. As the rider was always
placed at division 5 on the beam, the values given in the
table are double those actually obtained.

No. of
Experi-
ment.

M0l2+2Pa2

t

in seconds.

n

Weight
of rider
in milligram-
mes.

Mean Value.

1

145364

8-921

13*458

9*78

\

2

309356

1765

25*49

10-05

3

519769

20-435

19-12

9-55

f

/ 9*96 mgms.

4

130355

13‘10

34-71

10-47

J

5

130355

12-87

36-6

11-44

6

130355

12-72

35-50

11-35

7

130355

12-725

35-83

11-45

/

z1 11*35 mgms.

8

!

130355

12-81

35-5

11-20

9

130355

12-903

36-37

11-31

/

10 ,

454405

19-406 ,

22-08

10-58

* For this as for several other cases I removed the pans and hung the
weights directly by fine wires from the suspending-pieces. By this
means the resistance of the air was very much diminished.

39

Ordinary Meeting, December 24th, 1878.

J„ P. Joule, D.C.L., LL.D., F.RS., President, in the Chair.

“ Note on the Intensity of Moonlight,” by Harry Grim-
SHAW, F.C.S.

At the meeting of this Society held on the 26th of
November of the present year, some remarks were made
upon the relative intensity of moonlight, daylight during a
thick fog, and the diffused light of the electric arc.

The opinion was then expressed by some members that it
was very doubtful whether it was possible to read printed
type of anything like a small size by the brightest moon-
light in this country.

The light of the moon on the 8th of the present month
(December) being of considerable intensity, I took the
opportunity of making the experiment, which I have pre-
viously, at different times, performed more roughly, with
sufficient accuracy to form some standard of comparison.
The result was that I found it possible to read with cer-
tainty a still smaller type than I had previously known it
possible to peruse.

The types on which I experimented were those of a
newspaper, and known technically by the printers as
“ minion,” “bourgeois,” and “nonpareil.” These are all
smaller than the letters of the “Proceedings” of the Society,
which I believe is called “small pica.” The two first are
what are ordinarily used for such printing as that of news-
papers and the cheaper periodicals, whilst the last (“non-
pareil”) is a very small letter indeed. The last paragraph
of this note is printed in the type in question. The printed
matter in the “minion” and “bourgeois” letter was read with
Peoceedings— Lit. & Phil. Soc.— Yol. XYIII — No. 5.— Session 1878-9.

comparative ease ; the “ nonpareil” had to be perused
slowly, but could be made out with certainty.

The time at which the above experiment was performed was 8.15 p.m., and the
evening of course bright and cloudless. The moon was full at 7.49 p.m. the following
evening. The observers were three in number, who ail succeeded in reading the three
types, and it should perhaps be added, as a quantity affecting the results, that the
“ eyes" were all comparatively young, being under the age of thirty.

Ordinary Meeting, January 7th, 1879.

J. P. Joule, D.C.L., LL.D., F.R.S., President, in the Chair.

“ On Boulders of Clay from the Drift,” by E. W. Binney,
F.B.S., F.G.8.

In making the new railway from Manchester through
Cheetham Hill to Kadcliffe, a fine section of the drift depo-
sits has been exposed in the cutting at Moss Bank, south of
the bridge near Crumpsall, at an elevation of 207 feet above
the level of the sea. The beds occur in the descending
order as follows :

ft.

1. Clay containing a few pebbles , . . . . 12

2. Sand with beds of fine gravel 20

3. Clay containing the boulders of clay exposed. 1 2
The first-named bed would be termed by Professor Hull,
F.B.S., upper boulder clay, the second middle sands and
gravel, and the third probably lower boulder clay. — See his
paper on the Drift deposits in the neighbourhood of Man-
chester, published in vol. II. (third series) of the Society’s
Memoirs.

In No. 2, which is composed of fine stratified sand parted
by thin beds of gravel and deposits of drifted coal, are
found some basin-shaped deposits of gravel about 3 feet
long and 1 foot 6 inches deep, which not only contain the
pebbles usually found in the till much rounded, but also

41

rounded pieces of till or boulder clay of lenticular and sphe-
rical shapes, varying in size from one to three inches
through their major axes. The specimens on the table are
three taken out of the cutting by myself, and are a fair
sample of the average boulders.

There is not a section of the whole of the drift deposits
at Moss Bank, but at the Manchester Workhouse, about
quarter of a mile distant, the following deposits occur, the
second being the equivalent of No. 1 in the preceding sec-

tion :

ft. in.

Clay with a few pebbles 21 0

Quicksand 26 0

Loam 0 4

Clay 30 0

Clay in laminae 5 0

Clay with stones 4 0

Hard clay 0 6

Sand 2 0

Gravel 7 6

Clay (till) 25 0

Sand with small stones (thickness not given).

Rock (trias).

To my knowledge no instance of boulders of clay in drift
beds has been published. Many years since, when, obser-
ving the fine cliffs of till at Blackpool, I noticed how the
waves rounded the stones from that deposit which fell down
on the shore, and I also saw a few of the pieces of clay
rounded as well. In the last December number of the
Geological Magazine is a description of some clay boulders
by Mr. T. Melland Reade, F.G $., lately observed by him on
the Crosby shore near the river Alt. After describing a
trench about 50 yards long, 5 feet wide and 2 feet deep, cut
in the blue clay which underlies the peat and forest bed,*
and which formerly had only a deposit of sand at the bot-
* Quart. Jour . Geol. Soc., vol. xxxiv. p. 447.

42

tom, he says “ that at the present moment it is filled up
nearly to the surface with an agglomeration of rounded
lumps of clay more or less compacted together. The clay
boulders, for such they are, vary in size from 18 inches on
the longer axes to the size of a bean, and from a spherical
to an ellipsoid figure/’

“ We have not far to seek for their origin, as a visit to the
lower edge of the peat frayed into a sort of a subtidal cliff
or series of cliffs by the encroachments of the sea, shows a
deposit of similar clay boulders at its base. In the neigh-
bourhood of the beach the river Alt, meandering over the
shore, has made inroads on the post-glacial deposits which
compose the substratum, forming a subtidal river cliff of
blue clay at its western margin. Lumps of this clay under-
mined by the currents fall, break up into pieces, and get
rolled into boulders by the action of the tide. The trench
has formed a sort of trap for catching and retaining them.
The clay boulders are in contact, and become in the trench
compacted together into one solid mass, so that if it were
converted into rock its structure would show in some cases
distinct argillaceous boulders in a sandy argillaceous matrix,
and in others an imperceptible shading of the boulder
nucleus into the matrix.”

The boulders of clay found at Moss Bank have in all
probability been formed in a similar manner to those de-
scribed by Mr Reade, as they are found in a hollow in the
sand of a basin-shape in vertical section, which would be
somewhat like the trench described by him, having fallen
from an old cliff of till and been rolled by water into the
place where they are now found. In the sand are sometimes
found minute fragments of shells, but in such a state that it
is impossible to determine what they are.

48

Ordinary Meeting, January 21st, 1879.

J. P. Joule, D.C.L., LL.D, F.R.S., President, in the Chair.

“On an Old Letter of the late Sir Walter Scott.”

E. W. Blnney, Y.P., F.R.S., F.G.S., said that on March the
16th, 1868, he exhibited at the Society’s meeting an original
letter of the late Sir Walter Scott, dated the 4th June, 1802,
on the subject of an old Scotch Ballad called Jock o’ Milk.
Since that time he had come into possession of another
letter of the baronet’s, as well as one from Mr. Liddesdale.
They are as follow : —

“Sir, — I am honored with your very obliging favour, and
beg leave to express my best thanks for the information
which it so handsomely communicates. In the late Mr.
Riddell of Glenriddle’s MS., which I have frequently re-
ferred to in the late compilation, there is a copy of the
Ballad called Jock of Milk , which I examined very atten-
tively. I was only deterred from publishing it by the
strong doubts I entertained of its authenticity, as it appeared
to me to bear more the character of an imitation than of a
real ancient ballad. It is very possible, however, that I
may be mistaken, or that the copy I have seen may be
interpolated, and I shall be very much gratified indeed by
your furnishing me with the copies which you have so
handsomely offered to send me, with as much of the tra-
ditionary history as you recollect. I should be also much
interested to know whether the verses were taken down
from recitation or from a MS., ancient or modern. I have
been very desirous as far as possible to ascertain the
authenticity of the old poems which I have given to the
world, as literary forgeries have been but too often and too
justly imputed to the Scottish antiquaries. The Galliard
Proceedings — Lit, & Phil. Soc. — Vol. XYIII. — No. 6. — Session 187S-9

44

mentioned in your fragment was, I believe, a castle upon
the Seine belonging to the French monarchs, which gave a
name to the favourite dance there practised, just as a more
modern dance was called the Louvre , and as we call our
Highland dance a Strathspey. I beg you to believe that I
am extremely sensible of your polite attention to the re-
searches of a total stranger, and that I feel myself very
much gratified by the interest you have taken in them.

“I have the honor to be, Sir,

“Your obliged and faithful servant,

“Walter Scott/7

“ Laswade Cottage,

“ near Edinburgh,

“2 April, 1802.”

“ R. Cleator, Esquire,

“ Cropton Lodge, near Pickering, Yorkshire.”

“East Wood, 9th April, 1802.

“ Hear Sir,™ I am this morning favoured with your letter
of 7th, and lose not a moment in complying with your
desire. The old ballad of Jock o’ Milk was given to me by
Mr. Bell Irving, of Whitehill, and the notes thereon were
collected from old tradition, but really not having a copy
by me I cannot bring the whole to recollection. Mr. Bell
Irving’s grandfather, old Whitehill, was many years factor
or steward to the family of Castle Milk, and having access
to the Repository of all the deeds and papers belonging to
that antient place, lie found this ballad amongst them, so the
present Mr. Bell Irving informs me. From many enquiries
amongst veiy old people now no more, I could perceive
there had been such an old ballad, but of which they
had a very imperfect idea, but some time it strikes me that
two verses are added by the present Mr. Bell Irving. This,
however, you can easily detect by writing to him for every

45

particular, and you can then see that if it tallies with what
he told me. His direction is W. Bell Irving, Esquire, of
Whitehill, near Ecclefechen, N.B. If you have leisure,
and could take the trouble to copy the old ballad, with
notes, &c., I should then be able to point out something
more satisfactory than the above imperfect account is. —
Believe me ever

“ Yrs truly,

“ ft, Liddesdale”

“ William Cleator, Esqre,

“ Cropton Cottage, near Pickering.”

From the letter formerly published it does not appear
that Sir Walter Scott had ever his doubts removed as to
the genuineness of the old ballad. The above letters are
published in the hope that some reader may possibly take
up the subject and clear up the doubts, if this has not
already been done.

“On a further Analysis of the Water of the Mineral
Spring at Humphrey Head,” by C. Grimshaw and H.
Grimshaw, F.C.S.

At a meeting of this Society held on November the 28th,
1876, one of us, in conjunction with Mr. J. Barnes, read a
paper on some analyses of this mineral spring, samples
having been taken in the month of August in 1875 and
1876 respectively.

The above quoted paper also referred to an analysis of the
water of this spring by T. E. Thorpe, F.R.S., in the year
1868. It was noted that during this period the composition
of the mineral matter contained in the water had remained
remarkably constant during this period of eight years ; and
it was also proposed to ascertain, after the lapse of another
period, whether this constancy was still maintained.

The results of analyses performed with this view on a
sample taken on August 16th, 1878, we now beg to lay

46

before the Society. The following are the numbers ob-
tained :

(1) Total solid matter— -50 cc.

evaporated

and dried at

100°— 110° C. gave 03735

grms.

(2) Chlorine — (a) 5 cc. took 16-6 cc. standard silver nitrate

(1 cc. = 1 mgrm Cl).

(b) 5 cc. took 16-8

cc. standard

silver nitrate

(1 cc. = 1 mgrm. Cl).

300 cc. of the water gave

(3) Silica

.. 0'004 grms

. Si02,

(4) Iron and alumina — equal

.. 0-009 „

Pe203

(5) CaO—

.. 0-2125 „

CaO

(6) Mg2P207 — 0-1665 containing...

.. 0-06

MgO

(7) PtKaCV- 0-142 „

.. 0-0433 „

KC1

A calculation of these figures gives the following results :

Silica (Si02)

0-90 grains per gal.

Iron and alumina, as (Fe203)

. 2-10

Lime (CaO)

. 49-58

Magnesia (MgO)

. 14-00

5)

Sulphuric acid (S03)

. 76-58

5?

Chlorine (Ci)

.233-80

>>

Alkaline metals and carbonate ..

.145-94

522-90

A recalculation of the above results on the assumptions

as to combination of our previous analyses

gives the fol-

lowing :

Silica

0.90 grains per gal.

Iron and alumina

. 2-10

Calcium carbonate

. 8-40

})

Calcium sulphate

.109-72

}f

Magnesium sulphate

. 18-06

ft

Magnesium chloride

. 19-00

5)

Potassium chloride

. 10-11

Sodium chloride

,354-22

522*51

47

By an oversight in our analysis of November, 1876, the
potassium chloride is made 84 instead of 8‘4, which of course
affects the proportions of the two alkalies, but does not
alter the relations of the other salts. The potash in the
present analysis was determined directly, but in the former
by difference from the total alkali and chlorine.

On comparison, the water of this spring in the different
years alluded to will be found to contain a very constant
amount of mineral matter, which does not vary in compo-
sition to any great extent. The respective amounts of dif-
ferent years are as follows :

1868 — Thorpe 508 '5 grains per gal.

1875 — J. B. and H. G 5 10 ’3 ,,

1876— J. B. and H. G, 514-6 „

1878— C. G. and H. G 522-5 „

The flow of water on August 16th, 1878, was at the
rate of half a gallon per minute. This is just half the
rate found by Thorpe in 1868, who during the previous
two years had found the flow very constant. A long period
of small rainfall occurred just previous to the date of our
sample.

We may add, that in a paper read before this Society
(Second Series, Yol. XII.) by Mr. Binney, F.B.S., will be
found some additional information as to the geological
strata of the locality of Humphrey Head, accompanied by a
section of the Head and the neighbouring point, which
agree with the remarks on this point in our previous paper.

48

MICROSCOPICAL AND NATURAL HISTORY SECTION.

December 2nd, 1878.

Charles Bailey, F.L.S., in the chair.

Mr. Plant, F.G.S., stated that a specimen of the Black-
throated Wheat-ear (Saxicola stapazina, Temminck.) had
been shot at Raw tens tall, near Bury, Lancashire.

Professor W. C. Williamson, F.R.S., remarked that the '
supposed Radiolarium from the coal measures that he had
lately brought before the notice “of the Section, had been
submitted to Professors Haekel and Strassburger, and pro-
nounced by them both to be a spore.

Mr. Marcus M. Hartog, F.L.S., read a paper entitled
“ A Preliminary Abstract of an Investigation of the
Nervous System of Cyclops.5’

Two descriptions exist of the Nervous System of Cyclops ;
one by Zenker, who describes a chain of ganglia ; another
by Claus, completed by Leydig, correct so far as it goes, of
a brain, an aesophageal ring, and a ventral cord, only seen
in the last two thoracic segments, after which it is described
as forking. These last observers also describe the anten-
nary nerves as having each branch thickened in its course
into a ganglionic ring. I am able to confirm this, and to
add the following points : — The ganglionic swellings are
found near the terminations of all sensory nerve fibres. I
have succeeded in seeing the central nerve cord more fully,
i.e., from the 2nd thoracic segment onwards. At the end of
the 3rd segment it gives off a pair of nerves which pass

49

superficially over the ventral surface of the next segment
to the integument. At the end of the 4th segment not only
are there a pair of sensory branches given to the rudimen-
tory appendages, but just before a pair are given off to the
two large ventral muscles (originating from the sternum of
the 5tlr segment), on which each ends in a beautiful
nucleated Doyerian eminence. In the 1 st abdominal seg-
ment is the fork described by the two German observers,
but this takes its origin from the superficial (ventral) aspect
of the cord which is continued onwards under the colleterial
gland. After running obliquely outwards each branch of
the fork subdivides into two, an anterior sensory and a
posterior muscular branch. At the commencement of the
third abdominal segment the ventral cord forks, its branches
diverge slightly in this segment, but more in the next,
rising to the sides of the intestine, and having the ventral
muscles of this segment superficial to them. In the last
segment they have left the intestine and run about the
horizontal median plane straight into the axis of either
branch of the furca. I have only been able to detect two
crystal spheres in the eye of Cyclops; the anterior one in
Cyclopsine is here absent.

What seemed to me to be pits with a small mouth so as
to form a nearly complete sphere occurring in the rudimen-
tary legs of the last thoracic segment are probably sense
organs.

The ventral cord in Cyclopoids contains the elongated
nuclei everywhere found on nerve cords, but no ganglion
cells ; it has lost its significance as a sense organ, and is purely
commissural. No transverse commissures are found any-
where, even after its bifurcation. The cells on the sensory
nerve fibres suggest a functional displacement outward of
the local nerve centres.

Note added January 20th, 1879 ;

In the above abstract I have referred to a vesicle seated at

50

the base of the hfth segment, and apparently opening exter-
nally. Further work has shown to me that this is always
seated on the ganglionic enlargement of the nerve that
supplies the appendage ; that it opens at the ring marking
the insertion of the appendage ; that in the male it contains
one or several irregular brightly refractive bodies, floating
freely in its cavity. Hence I regard this organ as an ear,
less developed in the female than the male.

At p. 180, vol. 15, of the Proceedings of the Literary and
Philosophical Society Mr. Plant described a “Beetle of
good omen from Yucatan,” at which time he was unable to
give the generic and specific name. This can now be sup-
plied, as a similar specimen has been shown at a meeting of
the Entomological Society of London, by Mr. Randolph
Clay, from Mexico, and recognised as Zopherus Bremei.

51

Ordinary Meeting, February 4th, 1879.

E. W. Binney, V.P., F.R.S., F.G.S., in the Chair.

“ The Area of the Middle Drifts as determined by their
Contents,” by Alfred Bell, F.G.S. Communicated by
R. D. Darbishire, F.G.S.

The author, in working out the area of the middle drifts,
commenced by pointing out the confusion produced by the
sands, gravels, and boulder clays of the kingdom being con-
sidered, as has been done by some geologists, of the same
age. In proving this he has quoted the various forms that
characterise the different deposits, showing that in some, as
at Wexford, Bridlington, and in Scotland, the fauna under-
lying the boulder clay contains many arctic forms which are
wanting in the sands immediately above. These sands he
further traces by their contents over the middle east coast
of Ireland, the western and midland counties of England and
Wales, the Isle of Man, and the east and south coasts of
England. Having enumerated some of the derived rocks,
obtained in one pit alone, with numerous crinoids and
corals, a brief reference was made to the number and com
dition of these latter forms, 35 species of which he had found
in one collection alone.

Having pointed out the character of the middle glacial
marine fauna, he proceeds to show that the land fauna has
been subject to the same mutations, the fauna following the
climate.

A list of shells, about 140 species, obtained from the drift
gravels, forms an appendix to the paper.

Proceedings— Lit. & Phil. Soc.—Vol* XYITL- No. 7.— Session 1878-9,

52

Ordinary Meeting, February 18th, 1879.

J. P. Joule, D.C.L., LL.D., F.R.S., &c., President, in the

Chair.

James Bottomley, B.A., D.Sc., and Richard S. Dale,
B.A., were appointed Auditors of the Treasurer’s Accounts.

“On a Chemical Investigation of Japanese Lacquer, or
* Urushi,’ ” by Sad amu Ishimatsu. Communicated by
Professor Roscoe, LL.D., F.RS.

During a few months last year I had the opportunity of
examining roughly into the nature of “Urushi” in the
Laboratory of Tokio University.

The specimen of lacquer which I had under my examina^
tion was obtained from Kuyemon Nakamuraya, in Tokio, a
large lacquer merchant.

It is a milky juice of pale grey colour, and gives out a
certain kind of poisonous volatile gas. Some persons are
terribly attacked by this poison, producing a great swelling
where the acid comes in contact. During my examination
in the laboratory one of the apparatus keepers was terribly
attacked by this gas, producing ugly swellings all over the
face. He told me at the time it was exceedingly itchy.
By using the solution of chloride of sodium, carbonate of
soda, acetate of lead, &c., he was said to have recovered
within a week. This poison acts only on certain persons.
I had to work with it for many days, yet never had any
attack of the kind nor felt any uneasiness from it.

It has a sweetish characteristic smell and has an irritating
taste. It burns with very luminous flame, evolving dense
black smoke like oil of turpentine.

53

It is to a great extent soluble in benzole, ether, absolute
alcohol, &c., leaving behind a blackish grey residue in which
gum was found.

Lacquer on exposure to the atmosphere rapidly loses its
weight and at the same time blackens on its surface ; although
this loss is different in different specimens, yet on the average
of those which I have examined it seems to vary from 25
to 37 per cent.

When the lacquer is exposed to the action of sunlight in
hermetically sealed vessels in the atmosphere or in carbonic
acid, blackening does not take place, but a large quantity of
moisture collects on the sides of the vessel.

The loss of weight in the atmosphere is almost if not en-
tirely due to the escape of water, with a minute quantity of
carbonic acid which may be formed by the oxidation of
some organic compound existing in the lacquer. The attempt
has been made to estimate the relative amounts of carbonic
acid and water, yet it was not successful at the time, being
too difficult, and it must be left open to some future inves-
tigation.

It is by many supposed to be due to the combined action
of light and air that the blackening of lacquer in the air
takes place ; but this seems to be erroneous from the follow-
ing experiments. First, I made a square box which had a
well fitting sliding door and the inside of which was made
perfectly black, so that practically no light is admitted to
enter. In it was placed a small quantity of lacquer at dark
and the door closely shut ; on looking at it the next morn-
ing it was observed that the lacquer had turned perfectly
black, proving that it is not the light that blackens the
lacquer.

Second, the bottle in which I kept my lacquer for more
than three months during my examination was exposed to
the incident light of the laboratory; the surface of the
lacquer was turned perfectly black, forming a wall as it

54

were, while those portions which were in contact with the
sides of the bottle, which receive as much light as if
there were not any glass sides before it, were not at all
blackened. This phenomenon is just complementary to the
first one, proving that the blackening in the atmosphere is
in all probability due to the oxygen of the air, but not the
light alone, nor the combined action of light and air.

The lacquer when distilled with water gives a colourless
distillate which is slightly acid to test paper, and the
attempt has been made to examine the acid, but not
successfully on account of too minute quantity of the sub-
stance evolved. Distillation by itself and in a current
of steam was tried also, but the results in both cases were
the same as the first one. Lastly distilled with a small
quantity of dilute sulphuric acid, to aid the substance to
distil over, into sugar of lead, scarcely any precipitate was
obtained.

Lacquer mixes with any kind of fixed oil in all propor-
tions ; hence oil is often added as adulteration, but some-
times it is purposely added to increase its mobility.

The specimen of lacquer which I examined consisted of
the following three substances :

Part soluble in absolute alcohol

I.

II.

(resin)

58*24

58*23

Gum

6*34

6*30

Residue

2-24

2*30

Moisture and other volatile matter

33*175

33*170

100-00 100*00

As I have already mentioned, the lacquer loses its weight
very rapidly when exposed to the atmosphere. For the
above determination I weighed out each time samples from
well stoppered bottles, and determined the weight by
difference. Then this was treated with absolute alcohol and

55

the filtrate evaporated to small bulk and dried in an air-bath
at 1 00° C. until the weight remained constant. This is put
down as the part soluble in alcohol in the above analysis.
The residue was then treated with hot water and the filtrate
evaporated and dried at 100° and weighed as gum. The
residue after the gum had been removed was then washed
and dried on weighed filter at 100° C. and weighed as
residue. The moisture and other volatile matter were of
course determined by the difference.

The estimation of the amount of part soluble in alcohol
after the lacquer has been exposed to the sunlight in open
vessel for some 20 or 30 days shows that the soluble part
increased up to 72-82 per cent. This number when calcu-
lated for the substance to have lost 28 per cent moisture
and other volatile matter during exposure, then equals to
58*3 per cent, which is nearly equal and practically the
same as the analysis previously given, hence there seems to
have been no material change in the amount of matter
soluble in alcohol. Now the perfectly dried lacquer after
finely powdered was dried at 100°, and analysis gave

Fart soluble in absolute alcohol 18*07

Gum 3*63

Kesidue 78-30

100-00

Altogether from this analysis, the residue being increased,
the lacquer seems to have undergone some change, but pos-
sibly this is owing to the fact, that the alcohol as well as
water seem to have had less complete access to the material.

Thus the “ Urushi” consists of three principal constituents,
(1) a resinous part soluble in alcohol, (2) gum, and (3)
residue. Although there are, in addition to these, water and
volatile matter, as they go away sooner or later before it is
used, they are not properly called the constituents.

(1.) Part soluble in alcohol (resin) seems to be the principal

56

portion, and has a smell like ordinary lacquer, but it never
dries as the original does. It is brownish black, and slightly
sticky to the touch. When treated with potash solution it
forms a bluish black precipitate, but nothing is obtained on
addition of sulphuric acid to the filtrate.

When boiled with hydrochloric acid the resin is transform-
ed into a substance elastic while hot, something like the mass
obtained when heated sulphur is dropped into cold water.
When boiled with nitric acid, nitrous fumes are given out, and
the mass gradually becomes yellow, and finally a beautiful
orange coloured mass was obtained. This mass was washed
with hot water several times and then treated with absolute
alcohol; the mass was to a great extent soluble in the
alcohol, leaving behind a small quantity of a yellowish body
(which I think to be part not sufficiently acted upon by the
acid.) This alcoholic extract forms a beautiful yellow pre-
cipitate with both nitrate of silver and acetate of lead. I took
a quantity of alcoholic extract, precipitated it with acetate of
lead, and the precipitate was thoroughly washed with abso-
lute alcohol and then decomposed by means of dilute
sulphuric acid. (It might be better to decompose this salt
with sulphuretted hydrogen, but we cannot do so on account
of reducing action of this gas.) The mass was dissolved
again in absolute alcohol, then separated from sulphate
of lead.

Now then this separated alcoholic extract was again pre-
cipitated by sugar of lead, and after filtering and washing,
the precipitate was dried partially in an air-bath and carried
under the receiver of an air-pump and dried over sulphuric
acid.

This lead salt exploded when heated. The amount of
lead was estimated as oxide by igniting it with nitric acid.

57

And the salt was subjected to organic combustion. Nitro-
gen was determined by Dumas’ method.

The following numbers were obtained as the mean

results : —

Carbon 2 6 ’9 3

Hydrogen 4T1

N02 18-44

PbO 47 42

Oxygen 3*10

100-00

Now I prepared the silver salt of the same and obtained
18*5 per cent of silver as the result. It seems to give no
help as to the formula of this body.

As such was the case, I took alcoholic extract of the original
lacquer and precipitated it with acetate of lead, and after

requisite purification and drying the precipitate was

analysed. Lead determined as before. The following is the
mean of the results of two experiments which I was only
able to try :

Carbon 50 ‘450

Hydrogen , 5*705

PbO 3-775

Oxygen 40-070

100-000

(2.) The gum is soluble in cold as well as in warm water.
It has no smell, almost no taste, it has a yellowish or rather
brownish colour, and is of a non-crystalline body. It is
quite insoluble in alcohol. On subjecting this substance to
organic analysis I got the following percentage of hydrogen,

carbon, and oxygen :

I.

II.

Carbon

41-20

41-45

Hydrogen

6-51

6-58

Oxygen

52-29

51-97

1C0-00

100-00

58

These analyses yield a formula approximating to the
composition of common gum.

(3) The residue is, I think, nothing more than the mixture
of cellusose, bark, dust, &c.

In concluding my paper I must say that I am not at all
satisfied with my present analyses, but I thought it might be
of some interest to some of you from the point that, although
the varnished articles from this juice are so celebrated, yet as
far as I am aware, this is the first analyses of the kind that
has been heretofore attempted, and might be of some use to
those who are interested upon this subject.

Mr. William E. A. Axon called attention to the interest-
ing brochure on the arbre-d-lctque, by M. Paul Ory, pub-
lished in Paris in 1875, a copy of which he exhibited. M.
Ory was the first to give in a European language (French)
an accurate account of the method by which the tree was
cultivated and the sap extracted, and his description was
illustrated by many woodcuts from Japanese drawings.

“ On the Bursting of the Gun on Board the Thunderer,”
by Professor Osborne Reynolds, F.RS., Professor of En-
gineering, Owens College, Manchester.

In the interval which elapsed between the bursting of
the gun and the report of the Committee much thought and
some trouble has been expended in divining the possible
causes which might, under one set of circumstances or
another, have led to such a result. It now appears however
that different as have been the various suggestions they
all resembled each other in one particular, namely, that they
were all wrong.

59

It is to be hoped, however, that all the ingenuity that
has been expended will not have been thrown away and
that some improvement may result from the pointing out of
such numerous defects. That in some respects, such as the
increasing twist and the sudden steps or shoulders on the
outside of the gun, the present system is defective is shown
quite apart from the recent accident; and although it now
appears that the moving forward of the shot as the rammer
was withdrawn had probably nothing to do with this acci-
dent, it cannot be considered satisfactory that this moving
forward should be so much the rule as it is shown to have
been in the experiments recently undertaken.

Although at first sight it may appear that the fact of the
gun having been loaded with two charges of powder and
two shot is amply sufficient to explain the bursting, it
may not be useless to examine somewhat closely into what
would result under such circumstances. The bursting of a
38-ton wrought-iron gun is an experiment of which we
should make the most, as we cannot expect to have it often
repeated.

From the first accounts of the accident it appeared as
though the gun had simply broken in two, like a carrot, at
the first step, and that the front half had gone into the sea.
Such a failure would not have implied an excess of pressure.
It might have been caused by a great end strain, such as
would have resulted had the shot jammed when in full
career and carried away the fore part of the gun, or it might
have resulted from the gradual weakening of the section of
the gun at the shoulder owing to the different degrees of
expansion immediately before and immediately behind.
One or other of these causes appeared to afford the most
probable explanation of the phenomena as described in the

6 0

early accounts. In various subsequent reports, however, it
was stated that fragments of the fore part of the gun were
blown about in all directions. So that the gun, instead of
having simply broken in two, must have burst like a shell
in front of the first shoulder. This fact placed the pheno-
mena in an altogether different light. The explosive burst-
ing of the zone of the gun into fragments implied an
enormous excess of pressure at this point of the gun.

In order to cause the tube of the gun to burst longitudi-
nally at all would require several times the normal pressure,
and the breaking up of the wrought-iron tube into fragments
would show that the force was largely in excess of what
was necessary to burst it.

After seeing these reports it appeared certain that the gun
had been subjected, at the point of rupture, to a pressure
enormously excessive, and the question became, whence
could such a pressure have arisen ? To me it appeared that
nothing short of such an action as might, with a detonating
fuse, result from the explosion of gun cotton or dynamite
would explain the breaking of the gun into fragments.
Had the shot become jammed the pressure might have been
raised sufficiently to burst the gun, but with pebble powder
even this seemed doubtful, and such an action seemed alto-
gether inadequate to explain the breaking of the gun into
fragments. It appeared, therefore, that there was but one
conclusion to be drawn — there had been something abnor-
mal in the loading. Had the gun been loaded with small
grained powder, gun cotton, or dynamite, instead of pebble
powder, such a result might have been produced; but then,
the gun would, if it had burst, have burst at the breach
unless the shot had slipped forward, and that there should
have been two accidents appeared highly improbable. Be-
sides, it was necessary to consider what sort of a mistake
was most likely to have occurred; and the only possible
mistake that could have been made on the spot appeared to
be that of double loading.

61

Tlie fact that if two complete charges were put into the
gun, the powder of the second charge would he directly
beneath the point of rupture appeared in favour of this, the
easiest mistake. But would, supposing the powder to have
been pebble powder, the pressure from the two charges have
been sufficient to cause the result ? At first it seemed to me
that even supposing that the second charge had been ignited
by the first, which was doubtful, this would not explain the
suddenness or magnitude of the pressure. But on further
consideration it appeared certain that the second charge
would not be ignited by the fire from the first ; and it then
became clear that in this very fact we should have an amply
sufficient explanation of the excessive pressure.

My object in writing this paper is to point out the proba-
bility of this explanation, and so, if possible, to induce the
authorities to test it. It occurred to me several days before
the report of the Committee appeared, and in spite of the
improbability of such a mistake as double loading, I could
not shake off the conviction that it afforded the true expla-
nation. As I have pointed out, the blowing into fragments
of a wrought-iron tube implied an explosive action such as
might result from gun cotton or dynamite but which could
not be produced by the slow burning of pebble powder.
The point to be explained then is how the second charge
could be brought into such a condition that it would explode
like gun cotton. To understand this it must be remem-
bered that in the usual way the grains of gunpowder burn
from their outside only, so that the thicker the grains the
longer will be the time occupied in burning, and for the
same weight of powder the slower will the gas be given off.
The reason why gun cotton is so much more destructive than
gunpowder is not that it gives off more gas weight for
weight, but that when ignited by a flash it burns so much
quicker. If, therefore, by any means the whole mass of gun-
powder could be heated up to the firing point at the same

62

instant, so that the grains fired simultaneously inside as well
as out, the action of the powder would be as quick or
quicker than the gun cotton. And still further, if besides
being heated the powder was compressed into a fraction of
the space it usually occupies, the gases so confined would be
capable of a still greater pressure.

Now if the after cartridge were fired and the forward
cartridge were not ignited by the flash, and considering the
length and fit of the shot it could hardly have been so ignited,
then the after shot would be driven forward closing on to
the forward shot and compressing the powder between until
the pressure on the forward shot was at least half as great
as the pressure of the gases behind the after shot, which
would be between 10 and 20 tons on the square inch. Thus
the powder would be subjected to a squeeze between the
two shot such as would result from a blow. It would be
compressed to a fraction of its former volume. The cubes
would be crushed into a cake and the work of compression
would be sufficient to heat the powder far beyond its point
of ignition. Thus the entire mass of powder would be simul-
taneously ignited in a highly compressed and heated state.
The force of such an explosion would be practically unlimi-
ted and would be located at the very point at which the
gun burst. Hence in such an action we have ample cause
for the effect produced.

But it will be asked why does not the same thing happen
when a rifle is doubly loaded ? It is said that in that case
the second cartridge is generally blown out before it ignites,
and this may be so, for in the rifle the pressure of the gas
on the shot can never exceed above a twentieth part of what
it is in the 12-inch gun, and hence in the case of the rifle
its pressure may well be insufficient to ignite the powder
between the shot.

This view of the action resulting from the firing of powder
by percussion appears to me to be one which it would be

63

well worth while to test, for if proved it would completely
re-establish confidence in the strength of the guns, which has
been somewhat rudely shaken.

Let a 12-inch gun be loaded with a double charge of pow-
der and a double charge of shot, or a shot of double weight,
and fired. If, as is probable, the gun does not burst, confi-
dence in the gun will be re-established. Then let it be
loaded twice over with the powder between the shot so as
to ascertain whether the action of the powder when fired by
percussion would not produce an effect similar to that which
we are here considering. The destruction of one gun for
the purpose of establishing confidence in all the rest would
not seem to be an unworthy sacrifice.

PHYSICAL AND MATHEMATICAL SECTION.

January 28th, 1879.

E. W. Binney, F.R.S., F.G.S., in the Chair.

Dr. Bottomley called the attention of the Section to an
interesting copy of the Principia of Newton. In addition
to being an impression of the first edition it contains the
autograph of Edmund Halley. It was a present from Halley
to the Abbot Nazari.

Nazari was the editor of a scientific journal at Rome from

64

166Stol681. The following is the entry in Halley’s hand-
writing : —

Illustrissimo Duo
Dro Abbati Nazario
Romse humillime offert
Edm. Halley.

Subsequently the book was in the possession of Hr. Dalton,
and its value is enhanced by his autograph. It was con-
sidered desirable by the Section that some notice should
appear of this interesting book.

65

Ordinary Meeting, March 4th, 1879.

J. P. Joule, D.C.L., LL.D,, F.R.S., President, in the Chair.

Professor Reynolds, F.R.S., exhibited on behalf of Dr.
Roscoe, F.R.S., two samples of steel, one a piece of tungsten
steel, the other a piece of crystalline steel presented to Dr.
Roscoe with the following letter : —

44, Chorlton St., City,

February 28th, 1879.

Dr. Roscoe, B.A. F.R.S.

Dear Sir,

I send by bearer a piece of crystalline steel ingot
made here, melted in the usual way and poured into a metallic
mould. I consider it a good specimen of its class, in fact the best
I ever remember seeing.

When in this crystalline state it is technically called “ struck”
metal, and requires great care in re-heating and hammering, or else
it comes to grief. I have seen the interesting and varied collec-
tion you have for the use of students and send this as an addition
to the same, the acceptance of which will oblige,

Yours very respectfully,

WM. ANN ABLE.

Professor Reynolds also reported that Mr. W. Watts had
brought him some stalagmites of ice, of a mushroom shape,
quite clear, and about an inch in diameter. They were
found at the bottom of the puddle trench at Denshaw,
60 feet deep, and 7 feet broad. These stalagmites showed
that the mushroom shape is the result of being formed from
spray, and their transparency shows that water spray de-
posited on ice freezes into solid clear ice and hence confirms
the view that hailstones are an aggregation of ice particles.

Proceedings — Lit. &Phil. Soc. — Vol. XVIII. — No. 8. — Session 1878-9;

66

“ On a Modification of Bunsen’s Calorimeter/’ by Professor
Balfour Stewart, LL.D., F.R.S.

One object of the calorimeter devised by Professor Bunsen
is to measure the amount of heat given out by a small body
when cooled from the ordinary temperature of the air to 0°C.
For this purpose the body is dropped into ice-cold water
contained in a small tube which is then closed with a cork
to prevent change of air. Now the weight of the body being
small compared with that of the ice-cold water into which
it is plunged, the temperature of the latter never reaches 4°C.
or the point of maximum density of water. The heated
water will therefore be specifically heavier than that above
it and will remain at the bottom. Nothing can be better
than this arrangement for preventing the dissipation of the
communicated heat by convection or otherwise, but the
method employed by Bunsen of utilizing this heat has
proved difficult in practice. It is well known that he makes
use of this heat to melt ice contained in a vessel surrounding
the bottom of his tube and measures the change of volume
produced by the melting of the ice.

I should propose to surround this tube with mercury
instead of ice. In the above diagram t represents the tube
and M a vessel full of mercury into which the tube is tightly
inserted, the mouth of the tube extending above this vessel

67

and remaining open at t or being closed with a cork. The
vessel M is in fact a large thermometer of which the stem
and scale are at T. There is an air space which envelopes
the vessel M, and finally, around this, we have an outer space
filled with melting ice. W e may therefore suppose that at
the beginning of the experiment the water in the tube t as
well as the mercury in M will be at the temperature of
melting ice. Now let the small body whose specific heat we
wish to determine be dropped into the tube t. The heat
which it carries with it will remain at the bottom of this
tube and will be spent in very slightly heating the large
mass of mercury in M. This mercury being surrounded
with melting ice will receive no heat from any other quarter.
Its expansion will therefore be a measure of the heat com-
municated to the tube t , and although the whole rise of
temperature of the mercury will not be great yet the mass
being large it will act as a very open thermometer and the
heating effect will be indicated by a rise of mercury in the
stem T.

“The Poisonous Qualities of the Yew,” by William E.
A. Axon, M.R.S.L., F.S.S.

At our meeting, on the 9th Jan., 1877, Dr. Bottomley
made an interesting communication to the Society on the
real or supposed toxic qualities of yew leaves. The subject
recurred to my mind when on a recent visit to Stonyhurst,
for the failure of the main line of the Sherburnes, the ancient
owners of that mansion, is attributed to a similar cause.
Richard Francis, son of Sir Nicholas Sherburne of Stonyhurst,
died in 1702, at the age of nine, through eating some yew
tree berries, in the fine avenue at the eastern end of that hall.*
This tradition led me to make further inquiries. I was in-
formed by Mr. Thomas Kirk, farmer, of Whittingham, near
Preston, that he has known cases of the poisoning of cows
* Hewitson’s Stonyhurst College, 1878, p. 9.

68

and other cattle by yew leaves. In the spring of last year a
young horse came to an untimely end from the same cause.
The poisonous qualities of the yew tree has in that district
at least passed into a commonplace of agricultural belief.
It then occurred to me that I had read something on the
subject in our older botanical writers, and on turning up
the fine old folio of Gerarde’s Herbal, enlarged by Johnson,
and published 1636, I found this passage The yew tree,
as Galen reporteth, is of a venomous quality, and against
man’s nature. Dioscorides writeth, and generally all that
heretofore have dealt in the faculty of herbes, that the yew
tree is very venomous to be taken inwardly, and that if any
doe sleepe under the shadow thereof it causeth sicknesse,
and oftentimes death. Moreover, they say that the fruit
thereof being eaten is not only dangerous and deadly unto
man, but if birds doe eat thereof, it causeth them to cast
their feathers, and many times to die. All of which I dare
boldly affirme is altogether untrue ; for, when I was young,
and went to schoole, divers of my schoole-fellows, and like-
wise myself did eat our fills of the berries of this tree, and
have not only slept under the shadow thereof, but among the
branches also, without any hurt at all, and that not at one
time, but many times.” He adds on the authority of
Theophrastus that “ labouring beasts die, if they do eate of
the leaves ; but, such cattell as chew their cud receive no
hurt at all thereby. * * Pena and Lobel also observed

that which our author here affirmes, and dayly experience
shewes it to be true, that the yew tree in England is not
poysonous, yet divers affirme, that in Province in France,
and in most hot countries, it hath such a maligne quality,
that it is not safe to sleepe or long to rest under the shadow
thereof.”*

A writer in Hardwicke’s Science Gossip, May, 1865, states
that thirty or forty deer in the park of the Duke of Beaufort,

* Gerarde’s Herbal, enlarged by Johnson, 1636, p. 1370.

at Badminton, were poisoned by nibbling the leaves of a
yew tree, the branches of it having borne down within their
reach by the weight of heavy snow. A lady (Helen Watney)
writing in July, points out that this is contrary to the idea
that the leaves are not poisonous to deer, sheep, or goats.
She mentions as a well-known fact, that leaves, whether
fresh or withered, are toxic in their influence upon horses.
Its juice, she adds, was considered a remedy for the bite of
a viper, and that in Germany, it is still a popular remedy
for hydrophobia. Dr. Taylor cites a case of a child having
been poisoned by eating yew berries. Death appears to
have ensued in a few hours. He names also a case of a
lunatic who died from eating yew leaves. “There is no
doubt,” he says, “ that the yew is a cerebro-spinal poison.
The symptoms produced by the leaves and berries are
pretty uniform in character : convulsions, insensibility,
coma, dilated pupils, pale countenance, small pulse, and
cold extremities are the most prominent. In two cases, the
subject of one — a girl about five years of age — died in a
comatose state in four hours after she had eaten the berries,
and the other a boy, aet. four years, died nineteen days
after taking the berries, obviously from severe inflammation
of the bowels.”*

Dr. Taylor adds that “ the nature of the poisonous princi-
ple is unknown, and it is not certain whether, with respect
to the berry, the poison is lodged in the pulp or the seed,
although it is most probable in the latter.”

It may be exhibited in another form, for Caesar, in the
Commentaries on the Gallic War, tells us that Cativolcus,
King of the Eburnones, unable to endure the fatigue either
of flight or of war, poisoned himself with the juice of the
yew tree, of which there is great abundance in Gaul and
Germany. (B. G. vi., c. xxxi.)

# Taylor on Poisons, 2nd edition, 1859, p. 843.

70

The poets share the popular belief. Father Newman in a
recently published poem, speaks of

some dark, lonely, evil-natured yew,

Whose poisonous fruit — so fabling poets speak—

Beneath the moon’s pale gleam the midnight hag doth seek.*

M. Mavine has found a poisonous alkaloid in the leaves
and seed of the common yew (Taxus baccata ), which is
named Taxine. It is nitrogenous, and evolves ammonia
when ignited with freshly-ignited soda-lime. Taxine is
present in greater quantities in the leaves than in the
seeds. — (Science Gossip, 1877, p. 141.)

It will be seen that there is considerable diversity in the
evidence as to the reality of the poisonous qualities of the
yew, both as to its leaves and berries. It seemed worth
while to bring this fact out in the hope of inducing some
chemist to turn his attention to a matter which still appears
to invite definite and decisive investigation. We all know
Pascal’s famous saying, that if Cleopatra’s nose had been an
inch longer or shorter, the entire course of subsequent history
might have been different. As a smaller example may be
mentioned, that popular belief at least regards a childish feast
on fatal yew leaves, as one of the main links in that chain of
events which has given Lancashire the famous Jesuit College
of Stonyhurst.

# Lyrics of Light and Life, edited by F. G. Lee, second edition, 1878, p. 8.

71

MICROSCOPICAL AND NATURAL HISTORY SECTION.
January 8th, 1879.

Charles Bailey, F.L.S., President of the Section, in the

Chair.

Mr. Hastings Charles Dent, of the City Surveyor’s Office,
Town Hall, and 112, Bury New Road, Manchester, was
elected a member of the Section.

Mr. Thomas Rogers read a paper on, and exhibited many
specimens of, ballast plants collected at Cardiff in Septem-
ber, 1878.

The following list shows that the majority of the plants
collected are of South European origin, interspersed with a
few North American and Eastern Indian species.

Foreign Plants— Cardiff Ballast.

Natural Order. Native Country.

London Encyc,

RanunculaceEe ...Nigella damascena South Europe

Cruciferse Berteroa incana „ „

Camelina foetida ,, „

Bunias orientale Levant

Sisymbrium pannonicum . . . Hungary

Iberis umbellata probably an escape

from gardens

Erysimum orientale Levant

Resedacese Reseda Durisei Algiers

Malvaceae Lavatera punctata Italy

Malva nicoeensis „

Limnanthaceee . . . Limnanthes sulphurea California

Zygophyllacese ...Tribulus terrestris South Europe

Leguminosse Anthrolobium scorpioides . . . „ ,,

Cicer arietinum ,, ,,

Coronilla varia Europe

72

Scorpiurus sub villosus Europe

Medicago littoralis Italy

Melilotus coerulea Switzerland

Astragalus hamosus Spain

Trifolium nigrescens Italy

Melilotus alba... „

Hedysarum coronarium... ... „

Caryophyllaceee ...Saponaria vaccaria Germany

Onagracese Clarkia pulchella North America

CEnothera biennis „ „

„ odorata South America

Composite© Scolymus hispanicus ..Spain

Nardosmia fragrans Italy

Inula viscosa South Europe

Centaurea melitensis Malta

Xanthium spinosum South Europe

Erigeron Canadense North America

Actinomeris squarrosa 1 „ „

Solidago lanceolata „ „

Scrophulariaceee . . . Scrophularia canina var South Europe

„ green flowers ?...

Linaria elatine var. Sieberi. . .Gandia

Labiatae Sideritis montana Austria

Salvia verticellata Germany

Stachys Italica Italy

Boraginacese Heliotropium europeum ...Europe

Echinospermum Lappula ... „

Plantaginacese ...Plautago arenaria Hungary

Amaranthacese . . . Amaranthus chlorostachys. . . South Europe

,, retroflexus North America

Chenopodacese . . . Chenopodium ambrosiodes . . . South Europe

„ Botrys „ „

Euphorbiacse Euphorbia segetalis „ „

Urticacese Cannabis sativa India

Narcissus Tazetta Spain

Gramine&e Crypsis schoenoides South Europe

Zca mays India

73

Panicum miliaceum East Indies

Lep turns incurvatus

iEgilops ovata South Europe

Alopecurus utriculatus „ „

Phalaris paradoxa Levant

, , cserulescens Spain

The following British plants occurred on the Cardiff
Ballast Heaps.

British Plants.

Papaver somniferum and P. argemone.

Lepidium Draba and L. ruderale.

Sinapis nigra.

Senebiera didyma and S. coronopus.

Nasturtium terrestre.

Erysimum Cheiranthoides.

Sisymbrium Sophia.

Arenaria serpyllifolia, var. leptoclados.

Cerastium arvense.

Herniaria glabra and H. ciliata.

Polycarpon tetraphyllum.

Reseda alba.

Lavatera arborea.

Lavatera sylvestris.

Linum usitatissimum.

Geranium rot undifolium.

Melilotus vulgaris.

Trifolium fragiferum, and T. resupinatum.

Trifolium suffocatum, and T. stellatum.

Trifolium incarnatum, and T. Ochroleucum.

Trifolium maritimum,

Medicago falcata and M. denticulata.

Yicia lutea.

Lathyrus aphaca.

Lythrum hyssopifolium.

Epilobium.

Coriandrum sativum.

74

Eryngium campestre.

Bupleurum rotundifolium.
Centranthus ruber.

Cnicus marianus.

Gnaphalium luteo-album.

Artemisia campestris.

Solanum nigrum, in large bushes.
Datura stramonium.

Hyoscyamus niger.

Senecio squalidus.

Lactuca virosa.

Anthemis arvensis.

Veronica Buxbaumii.

Linaria spuria.

Linaria elatine and var. Sieberi.
Scrophularia Scorodonia.

Salvia clandestina.

Chenopodium rubrum.

Cynodon Dactylon.

Digitaria humifusa and D. sanguinalis.
Panicum crus-galli.

Setaria viridis and S. glauca.
Gastridium lendigerum.

Polypogon Monspeliensis.

Agrostis spica-venti.

Agrostis alba, var. stolonifera.

Lolium temulentum.

Poa loliacea.

75

General Meeting, March 18th, 1879.

J. P. Joule, D.C.L., LL.D., F.R.S., &c., President, in the

Chair,

Mr. Hastings Charles Dent, 112, Bury New Road, Man-
chester, was elected an Ordinary Member of the Society;
and Monsieur A. Letourneux, Conseiller a la Cour d’Appel
d’Alexandrie, Egypte, was elected a Corresponding Member,

Ordinary Meeting, March 18th, 1879.

J. P, Joule, D.C.L., LL.D., F.R.S,, &c., President, in the

Chair.

“ On Siliceous Fossilization, Part II.,” by J. B. Hannay,
F.R.S.E., F.C.S., Assistant Lecturer on Chemistry in the
Owens College.

In a former paper it was shown by chemical and optical
means that the fossil siliceous rods Hyalonema Smithii were
identical in constitution with those from modern sponges, and
that the curious nodulised appearance of some of the rods was
due not to the original form of the rods, but to certain physical
and chemical changes which have passed over them since they
were deposited where they were found. It was also shown
that of the three forms of silica, transparent, gelatinous, and
opaque, the first and second were easily acted upon, and
retained the original structure of the organic silica, whereas
the last was in the truly mineral form and had lost every
trace of organic structure, and was not easily acted upon by
chemical means. Mr. John Young, F.G.S., having kindly
Proceedings— Lit. & Phil. Soc.— Yol. XYIII.— No, 9.— Session 1878-9.

76

supplied me with several specimens of the fossils from the
limestone quarry at Kilwinning, which are very different
from those I previously examined, and which throw more
light on the changes which siliceous fossils may undergo, I
beg to give an account of them to the Society, One piece
of limestone simply contained (instead of rods) a number of
cylindrical holes where the rods had lain. In Fig. I, which

is a woodcut from a photograph, are seen these cylindrical
holes which plainly show that the rods have been dissolved
away. The solvent must have been a strong calcareous or
other alkaline solution, as the calcareous fossils are not in
the least disfigured. In. Fig. 2 we see a beautifully pre-
served sample ofFenestella, and we know that a very slight

solvent action would have destroyed the structure of these
delicate organisms. From other internal evidence, such as
little shells and diatomaceae, it is clear that the calcareous
portion of this limestone has not been at any time dissolved
to any extent, and yet such an obdurate substance as silica
has been completely removed. Then as to the cause of its
removal. The solution was no doubt highly calcareous, but
we know that highly calcareous water may run over quartz
crystals for a very long period without having the slightest
effect upon the faces. I think that Fig. 3 will explain
how the rods came to be so easily dissolved. This is a
photograph of a hollow where a rod has lain which still
contains some rounded nodules of silica. It will be seen
from my former paper that these nodules are anhydrous
inorganic silica, crystallizing out of the hydrated silica after
the rod has undergone a little dehydration since it was
alive. Now here we see the whole rod dissolved except
such portions as were entirely mineralised, if I may use
such a term, so that we see that the reason these silica rods
were so easily dissolved by the calcareous solution was
because the silica of which they were composed was in a
hydrated easily soluble form. Thus the existence of those
nodules which had before puzzled naturalists now gives us
the clue to the state of the rods at the time of solution.
Fig. 4 will still further elucidate this subject. Here it
will be seen we have a large number of rods partially dis-
solved. I have examined by the means given in my former
paper above twenty samples of these partially dissolved
rods, and I have not found one sample containing water, so
that again we see the whole of the thoroughly mineralised
silica is left behind, and those portions which were very
probably hydrated dissolved. I say very probably, for we
see that the solvent action has gone on in a very irregular
manner and in a manner which could not be accounted for
on any circulation hypothesis, but just in such a manner as

78

would be caused by the irregular manner in which the rods
get mineralised.

It might be expected that since the rods were so neatly
and perfectly dissolved out, the spaces might get filled up
with carbonate of lime and reproduce the silica rod as a cal-
careous fossil ; but although 1 have examined some hun-
dreds of those fossils, I have not found one case of this
nature. The only cases I have found even approaching to
this is when the centre of the rod is dissolved it is some-
times, as in Fig. 5, filled in with carbonate of lime. I have
noticed that when carbonate of lime is deposited in the
cavity where the rod lay it is highly crystalline, and could
never be mistaken for anything organic. Fig. 6 is from
a photograph, showing the carbonate of lime in the silica
centre.

As the above remarks border on a subject which has
been discussed very extensively, I may be allowed to point
out that they settle one half of the discussion, namely, that
silica may be dissolved in presence of calcareous fossils; but
the other half, namely, whether or not the spaces so left
may be filled up with carbonate of lime so as to look like
fossils, is still an open question.

PHYSICAL AN I) MATHEMATICAL SECTION.
February 25th, 1879.

E. W. Binney, F.RS., F.G.S., in the Chair.

“ On the Mean Temperatures of the Winters of the last
29 Years,” by the Kev. Thomas Mackereth, F.R.A.S., &c.

It may be considered somewhat premature to institute a
comparison of the mean temperatures of the last 29 years

79

when the colder of the extreme of the winter months has
not yet been entered upon, viz., the month of March. In a
meteorological sense winter may be considered as including
five months of the year, viz., November, December, Janu-
ary, February, and March. But January, so far as low
temperature is concerned, is the pivotal month of the
winter, and March has a mean temperature slightly below
that of November. The difference is so small, only about
0-7 deg. Fahr., that in comparing the mean temperature of
winters the mean temperature of these two months may be
practically neglected. The mean temperatures deduced
from my own observations extend over only 17 or 18 years;
but the late G. V. Yernon, Escp, F.B.A.S., was kind enough
to furnish me with the weekly temperatures he had deduced
from the year 1850 onwards till 1861, when I began to
make my own observations and deductions. That the mean
temperatures here presented may have a common basis I have
calculated them upon the weekly mean temperatures of the
last 29 years, which of course include those of the late Mr,
Yernon.

The results are as follows for the winters extending from
the first week of December in one year to the last com-
pleted week in February of the year following.

Winter of

.Mean

Temp.

Winter of

Mean

Temp.

1850-1

... 40-3°

1865-6

... 41-9°

1851-2

... 39 ’8°

1866-7

... 39-9°

1852-3

... 39*9°

1867-8

... 400°

1853-4

... 37-3°

1868-9

... 43*6°

1854-5

... 35-1°

1869-70

... 37-1°

1855-6

.. 37-3°

1870-1

... 35-6°

1856-7

... 37*9°

1871-2

... 40’3°

1857-8

... 39-4°

1872-3

... 39-2°

1858-9

... 41-0°

1873-4

... 40*6°

1859-60

... 35-4°

1874-5

... 38-6°

1860-1

... 36-4°

1875-6

... 38-8°

1861-2

... 39-3°

1876-7

... 42-3°

1862-3

... 41-9°

1877-8

... 39-6°

1863-4

... 37*9°

1878-9

... 31*4°

1864-5

.. 36-6°

80

From the above table of winter mean temperatures it will
be seen that the coldest winters of the last 29 years were in
1854-55, 1859-60, 1870-71, and in 1868-69; and that the

present winter is colder than the coldest of these, viz.
1854-55 by 3’7 deg. or 12 per cent. The mean temperature
of the winter months for 29 years is 3 8 *7 deg. And whilst

the winter of 1854-55 was 3'6 deg. or a little over 9 per
cent below the average temperature, the present winter is
7*3 deg. or 19 per cent below the average winter tempera-
ture.

The accompanying diagram sets forth the ratio of all the
winters from 1850-51.

w

(

!

C0

|

«

CD

I

m

i

IfJ

1

Q

Ifi

1

Q

1

in

I

m

VJ

03

to

!«>

«*■>

03

CO

00

CO

GO

03

WINTER

0

38-7

MEAN

BBaHHinHIHBIBHBBHHHIIBBHIiH

flflflBflfl«BflBBBflflBBB»HBBBflBBBBH|

flBBBflBHBBBBBBBflBBU«BHBBBBBHflfl

BBBBBBBBBBBKliBBBWBMMBBmBBBMKlBB

SflBBBBBB«BBrJBBBIHB!flNBV!BRBBFJKBB

KBBBIIKflLlirailHIiSHBiil^ViKBlLWBBiBB

BflHBflRBBllBrJBBBrBBRHBBflflBRflBBlflfl

■■■NRaHBBBfJBB^BBBHBBriflflBBBB&VB

BflBUrJBBMHJSflBBBflBflBMKBBBflBBflllB

BflfllflBBBBBBBflUnHHIBflBBBBlg

HWWBMWIIHWWHI

YEARLY

480

MEAN

BBBIIflBBBBflBBHMKMHBIBHBHflBBi

■■■■■■■■MBaBamamaiMMiian

niiiiiunBiinimmnni

■■■■■■■■■■■■■■■■■■■■■■■■■■■■a

SUMMER

0

58-1

MEAN

BBBBBBHflBBBBBBBBKBflBBflBBBRBBfl

BIBflBBBBBBBBBBBflMklRBiBflBBBBflB

mmmrnmummmwimmmmmmmmrA^rd^mmwMWAmu

BBBBBBBIBBBklBflKIBiSflHBBflBBBBKBBI

iiiiiiiiiiiaiiiiiniiiiiiiiii

■■■-■■■■aWMBMMi—MaM

tn

u

s

m

h'

CQ

03

ea

09

•»*

81

Here it will be seen that five years elapsed between the cold
winters of 1854-55, and 1859-60; but that six years elapsed
between the cold winters of 1864-65, and 1870-71, and that
eight years elapsed between the present cold winter and the
previous one of 1870-71. It is now known that the
sun spot period is irregular and not so nearly an interval
of 10, 11, or 12 years as was imagined. The minimum of
the sun spot period happened about two years ago, but it
is still at a minimum, and very seldom have spots been seen
on his disc during the past year. Whether these cold
winters are traceable to this solar inactivity or not, the pre-
sent coincidence is very striking.

In the same diagram I have presented the ratios of the
mean summer temperatures of the last 18 years. These
ranges are included in the weekly mean temperatures of
June, July, and August, and will be seen to be far less than
the ranges of the winter mean temperatures. This perhaps
may be accounted for by the relative difference of the
amount of atmospheric vapour existing in the air in the two
opposite seasons of the year. In the winter season the ratio
of atmospheric vapour reaches 87 per cent, whilst in the
summer season it reaches only about 75 per cent. But
whether this is so or not, there is the fact. Here it will be
seen that between the hot summer of 1861 and the still
hotter one of 1868 there is an interval of seven years ;
since then the coming summer will make an interval of 11
years. In the interval of 7 years there was only one sum-
mer with a temperature slightly above the average, 1865;
all the other summers of this interval were mostly far below
the average ; but in the 11 years’ interval all the summers,
with only two exceptions, have either been above or equal
to the average summer temperature. The ratios of the
summer and winter temperatures have not the slightest
relationship to each other. Hence it is impossible to form

82

any idea from the temperature of a winter what kind of
summer temperature may follow.

I have shown on the same diagram the mean tempera-
ture of each year from 1861 to 1878. The mean of all is
48‘0 deg. The ratios of their differences are extremely
small, so small indeed as to be of no practical value ; for
between the coldest year and the warmest of the last 17
years there is a difference of only 2*9 deg., and the mean
difference of temperature of all these years amounts to only
0 3 deg. These differences do not, from the data I have,
seem to observe any definite rule.

83

Ordinary Meeting, April 1st, 1879.

Edward Schunck, Ph.D., F.R.S., &c., Vice-President, in

the Chair.

Among the Donations announced was a Portrait of Mr.

E. W. Binney, F.R.S., &c., painted by Mr. William Herbert,
Johnston, and presented by the President, Dr. J. P. Joule,

F. RS., &c.

On the motion of Dr. R. Angus Smith, F.RS., seconded
by Professor W. C. Williamson, F.R.S., it was resolved That
the cordial thanks of the Society be given to Dr. J oule for his
valuable donation.

Mr. J. H. Poynting, B.A., exhibited an autograph dedica-
tion to M. Humbolt, of “Extrait d’un mdmoire sur la
Thdorie des tubes capillaires,” by M. Laplace, of which the
following is a copy :

Pour Monsieur Humbolt. De la part de l’auteur.

Je prie Monsieur Humbolt d’agre'er ce petit mdmoire
comme un hommage de tons mes sentimens d’estime et
d’attachement bien sinceres. M. Berthollet, qui est avec
moi dans ce moment, me prie d’y joindre les siens.

Nous nous rappellons l’un et l’autre au souvenir de M.
Gay Lussac.

“Two Deductions from Mr. G. H. Darwin’s Letter in
Nature , Feb. 6, 1879, upon Sir W. Thomson’s Equation of
Cooling,

* = V0 +

2V

X

— -Z

2 Jkt

dz

by Mr. James Heelis.

Proceedings — Lit. &Phil. Soc. — Yol. XVIII. — No. 10. — Session 1878-9.

84

If the expression

be integrated we get

r<-i

2 V

v = Y0+—ze

V

1 +

2

?} +

22

24 +

23

7 r

1-3 1-3 1*3. 5 *7

-z 6 + <fec.

X

where z — — — == * Taking Mr. Darwin's value for v in order

that it may give the point of maximum cooling of the mass
at any given time reckoned from the commencement of
cooling (f = \ or x1 = 2 Jet) the above becomes

2V / 1 1 1

v = Vo

s/2

7,(

1 + l-3 +

1'3’5 1-3-5-7

+ &c.

)

2-8213722V

" V° + v'Tx 2-7182818 x 3:H"l5926

V, + V, V, - V,

= V„ + -6826894V or putting V0 = V— a- V = * 2

z z

= -8413447V! +T586553V2.

where VDhj are the initial temperatures at commencement
of cooling, a very surprising result, showing that the tem-
perature of the point of maximum cooling of the mass is
constant and that if Mr. Darwin’s assumption as to time is
to be admitted, at about 100 miles below the earth’s sur-
face there is a temperature -f-ths of what pervaded the mass
when cooling commenced.

Mr. Darwin’s deduced relation x* = 2 id must be taken
with a qualification. It will give the plane on which the
maximum cooling of the mass is taking place at any time,
but it will not give the time at which the maximum cooling
takes place in any plane.

To show this take the equation which he deduces for the
rate of cooling, viz.

x 2

civ _ V xc~i Jt
dt 2 y/ 7r/d'l

log( - sf ) - logC + loga; - ~ m

85

Differentiate with respect to x, supposing t an arbitrary
constant,

1 tov dtj _l_x

_ dv dz x 2/ct

dt

which equated to 0 gives Mr. Darwin’s relation x 2 = 2ht.

But if you assume x to be an arbitrary constant and diffe-
rentiate with respect to t, you get

_l_.cflog(~§)_ 3 *

civ dt 2(5 4 /ct2

dt

• OC^1

which equated to 0 gives t = •

These two relations between x and t show that in any plane
the maximum rate of cooling takes place in one third of the
time (measured from the commencement of the cooling) that
the maximum rate of cooling of the mass takes place in that
plane.

The conclusion from this appears to be that if it be ad-
mitted that the contraction is proportionate to the cooling,
the principal contraction in any plane will take place long
before that place is the seat of the maximum cooling of the
mass.

I ought to have stated above that both x2 = 2 kt and x 2 = QJct
give negative values for the second differential coefficient.
That is, of course they do give maxima and not minima.

“ Arrangement of a Tangent Galvanometer for lecture-room
purposes to illustrate the laws of the action of currents on
magnets, and of the resistance of wires,” by J. H. Poynting,
B.A., Demonstrator in the Physical Laboratory of the Owens
College.

Three coils of similar wire are arranged round the circum-
ference of a circle with a compass needle at the centre, each
wire going only once round the circle. The six ends of the

86

three wires are connected by thick copper wires with the six
binding screws AB,CD,EF.

On a concentric circle of twice the radius is arranged a
coil of the same wire going twice round the circle and having
its ends connected by thick wires with the binding screws
GH. On the same circle is a single wire of twice the
diameter, making only one turn round the circle, and having
its ends connected with the binding screws KL.

The coils are denoted respectively by the numbers 1 — 5.

The null method is adopted in each case. That is two
forces acting on the needle and arising from different

87

arrangements of the circuit are shown to balance each other,
and from the arrangements necessary to produce this equi-
librium the desired laws are deduced.

I. If the current be reversed the force is reversed. Intro-
duce the current at A. J oin BD and lead away at C. Then
the same current goes in opposite directions round the coils

(1) and (2), and since the needle is not deflected the reversal
of the force when the current is reversed is proved.

II. The force is proportioned to the length of current
acting. This is proved by the last, for the two coils (1) and

(2) exert equal forces on the needle. If the current went
round them in the same direction we should have twice the
force which each exerted singly, with twice the length of
current. This assumes that the current in different parts
of the circuit is the same, which might be shown by slightly
modifying I, thus, introduce between B and D various re-
sistances and the equilibrium is not disturbed.

III. The force is proportional to the strength of the cur-
rent. Introduce at A and connect A with C and B with
D, and connect D with F and lead off from E. There will
be two equal currents in the same directions in coils (1) and
(2), for they are exactly similar to each other and similarly
situated. These two currents unite to give a double current
in the opposite direction in coil (3), and the double current
in a single wire exerts twice the force exerted by each single
current, since there is no deflection.

IY. The force is inversely proportional to the square of
the distance. Introduce at A, connect B with H, and lead
off at G. Then since we have two turns to the coil (4) we
have a current of four times the length at twice the distance
acting in opposition to the same current through (I). Since
there is no deflection, the two exert equal forces, and there-
fore the force is inversely proportional to the square of the
distance.

88

Resistance.

I. The resistance is proportional to the length. Connect
B with 0, 1) with E, A with F. Introduce at A and lead
off at E. We have then a divided circuit joining A and E,
one consisting of the two coils (1) and (2), and the other
the coil (3) only one half the length and going in the oppo-
site direction. But as there is no deflection the current
through the first circuit of twice the length must be only
one half that through the other to exert an equal force, i.e.}
the resistance is doubled when the length is doubled.

II. The resistance is inversely proportional to the cross
section. Introduce at A, connect A with L, connect B with
C and D with K, and lead off at K. Then we have two
circuits connecting A with K, the first consisting of the two
coils (1) and (2), the second of the coil (5) of the same length
but of four times the cross section and going round in the
opposite direction. Since the needle is not deflected the
two currents exert equal forces. But the coil (5) is at twice
the distance and must therefore15 have four times as great a

o

current through it as that through (1) and (2). That is,
with equal lengths of wire of the same material connecting
two points the currents conveyed are proportional to the
cross sections.

“ On Aurin, Part II.,” by R. S. Dale, B. A., and C. Schor-
lemmer, F.R.S.

Some time ago we read a paper before this Society, in
which we stated that, on heating aurin Ci9Hi403 with an ex-
cess of aqueous ammonia, it is converted into pararosaniline
C19H17N3* There ought to exist two compounds, standing
intermediate between aurin and rosaniline, viz., C19H15N02
and C19H16N20, as the action of ammonia probably proceeds
in three stages :

c19h14o3 + nh3 = c19h16no2 + h2o

C19H15N02 + RH3 = C19H16R2Q + h20

C19H1gN20 + NH3 = OigH^Nij + H20

* Mem, Lit. Phil, Soc. (3) vi., 248.

89

We have made a very large number of experiments for the
purpose to get hold of one of these intermediate products,
and have at last succeeded in obtaining one, probably the
first, in beautiful crystals ; it dyes on silk and wool a rich
red, and as the commercial red aurin, which is obtained by
the action of ammonia on common or yellow aurin, has also
been called peonin, we will retain this name for our com-
pound. It is formed by heating aurin with dilute ammonia
to 100°C for some weeks ; a body dyeing exactly the
same shade, and therefore undoubtedly the same compound,
is obtained by passing for a few hours ammonia gas into a
solution of aurin in boiling amyl alcohol.

As we encountered many difficulties in the preparation of
peonin, we thought more definite results might be obtained
by using a compound ammonia, and therefore tried the
action of methylamine on aurin. Methylamine is now a com-
mercial article, being obtained from beetroot-molasses by M.
Vincent’s method, which Dr. Roscoe described to this society
some weeks ago ; he was kind enough to present it with the
methylamine required for our experiments.

On heating the two bodies together for a few hours, the
deep red colour of the liquid became much paler and a brown
deposit was formed in the tubes, which on examination was
found to be trimethyl-pararosaniline , which is formed ac-
cording to the equation :

C19H14O3 + 3(CH3)NH2 = C19H14(CH3)3N3 + 3H20.

We have dyed with it, as well as with the other bodies men-
tioned in this paper, silk, wool, and mordanted cotton, and
beg to submit these samples to your inspection.

We have already proved that by acting on aurin with
aniline, the final product consists of triphenyl-pararosaniline
and thus shown, that the whole host of bodies, known as the
aniline colours, can be obtained from phenol.

90

“ Screw Propulsion/’ by Robert Rawson, Assoc. I.N.A,
Hon. Member of the Manchester Literary and Philosophical
Society, Member of the Mathematical Society.

Preliminary Proposition .

1. Suppose AB in the annexed diagram to be the axis of
the screw propeller ; draw CP perpendicular and DPE
parallel to AB. Consider now an element of the screw pro-
peller blade having an indefinitely small area (n) to be

placed at P, whose distance from the axis AB is denoted by
(r). The element (a) thus placed at P has, therefore, a normal
line, that is, there is a line perpendicular to it which is
called a normal to the element (a). Let GF be the projec-
tion of this normal line upon the plane A BP ; and, further,
suppose the position of this normal through P to be deter-
mined by the angles a, (3, y, which it makes with AB, CP,
and a line perpendicular to the plane ABP respectively.
These angles are not, however, independent ; they are con-
nected by the well known equation

Cos2a -f COS 2/3 + COS2y =1 1

2. As CP revolves about the axis AB with an angular
velocity (u), the element (a) of the screw propeller blade
strikes the water in the direction of its normal line in
accordance with the usual theory of fluids. And, therefore,

91

for any assumed angular velocity (u) the greater the velo-
city of the element is in its normal direction the greater is
the force with which the element of the screw propeller
blade will strike the water.

In consequence of this it is absolutely necessary to com-
pute geometrically the normal velocity of the element (a)
by means of the data supplied by the dimensions of the
propeller, its angular velocity (u) and its velocity (y) in the
direction of the axis AB, in order to determine the amount
of resistance to angular motion and motion parallel to AB.
This is the preliminary proposition the solution of which
can be found without any reference to the theory of the
resistance of fluids.

3. Suppose, then, that the element ( a ) placed at P is sub-
ject to the influences of two causes, viz. the velocity (rw)
perpendicular to the plane ABP. and the velocity (v) paral-
lel to the axis AB. The object now is to find an expression
for the normal velocity arising from these two causes.

To do this it is only necessary to resolve (ru) the angular
velocity and the velocity (y) parallel to AB into two direc-
tions, viz. : perpendicular and parallel to the normal line.
Thus is obtained,

rwcosv — velocity parallel to normal,
rwsinv = velocity perpendicular to normal.

The latter velocity produces no effect upon the water, as
friction in this case is entirely disregarded.

The former, however, is the velocity with which the
element (a) of the propeller blade strikes the water in the
case when there is no motion parallel to AB.

The effect of (v) the velocity parallel to AB, in the direc-
tion of the normal to the element ( a ) must be deducted
from ('mcosy) in order to obtain the full normal velocity
with which the element ( a ) strikes the water. The resolu-
tion of (y) in the direction of the normal will be vcosa,

92

hence, denoting the absolute normal velocity by N, the
following equation obtains, viz. —

N — rucosy - VCOSa 2

4. The normal velocity then as expressed by equation (2)
can be made to assume different values by assuming different
values of the available angles a, v which determine the posi-
tion of the normal line to the element (a) of the propeller
blade.

The normal velocity of the element ( a ) will be zero, when
the following relation between the angular velocity (u) and
the velocity of translation (V) obtains, viz.

rucos.y o

* Hill •e©ooo*oooooooo£aoo»oo«eo O

COS. a

This equation is derived directly from equation 2.

It appears, therefore, that when the element (a) moves
in accordance with the relation (3) it produces no resistance
whatever either to rotation or translation along the axis of
the propeller. In this case the element (a) moves upon
a surface which may be not inappropriately denominated
the surface of vanishing pressure.

5. With reference to equation (1) Art. I., it will be readily
seen that the condition a,v being complimentary (that is,

a + v = ^ will give (3 = zero. Hence, in this case, the normal

line of the element {a) placed at P is situated in a plane at
right angles to the radius (r). Further, if each of the two
angles a,r remains constant for the same value of (r) as well
as satisfy the above condition, then the curve of the pro-
peller at (r) distance from the axis will be the common
helix of the Archimedean screw as used in Her Majesty’s
Navy.

6. In the determination of the formula 2 Art. 3 it was
assumed that the element (a), with a normal velocity N,
struck the water when perfectly at rest. The position,
however, of the propeller practically placed at the stern of

93

the vessel which it propels, leads to the conclusion that this
assumption is by no means a correct one. A slight correc-
tion in the formula 2 will therefore be necessary to meet
the case when the element (a) strikes the water which has
a velocity (V) in the direction of the axis A.B. By resol-
ving Y in the direction of the normal line the result will be
Ycosa. This resolved velocity must be added to N in
equation (2), then it follows that the element (a) striking
the water at rest with a normal velocity N1 where

N1 = rucosy - (v - V)cosa (4)

will be exactly the same as the element (a) striking the
water, having a velocity Y in the direction of the axis, with
a velocity N — rucosy — vcosa.

In this case the surface of vanishing pressure is deduced
from (4) by the relation
rwcosy

v= — - + V 5

COSa

Equation (5) will do good service in explaining the perplex-
ing phenomenon of negative slip which has been one of the
experiences of screw propulsion by means of the common
Archimedean screw.

It will be observed that the element (a) of the screw pro-
peller blade can be made to assume any position in space by
assigning suitable values to the angles a, (3 , y which fix
absolutely the direction of the radius of curvature of the
propeller blade at the given point P. Now the question
naturally arises, from what has been said in the foregoing
articles, viz., what values must be given to the angles a, j3 ,
y at the point P, and how must they vary from point to
point on the propeller blade, so that the resistance in the
direction of the axis shall be a maximum when the resist-
ance to angular motion is a given quantity ?

It is hardly necessary to add that the solution of the
above problem is not easily accomplished. It is to be hoped,
however, that practical experience in union with mechanics

94

and geometry of the propeller blade will, ere long, give an
answer sufficiently accurate for all practical purposes. The
Council of the Society of Naval Architects have promised a
Gold Medal to the best solution during the year 1879.

Dr. R. Angus Smith, F.RS., exhibited a section of a
large Eucalyptus globulus, and drew attention to the pecu-
liar arrangement of the fibres in the different rings of the
wood.

Professor W. C. Williamson, F.RS., pointed out that the
peculiarities in the section of the Eucalyptus exhibited by
Dr. Smith arose from differences between the inner and
outer portions of each annual ring of the wood. In most
plants the fibro -vascular structures of the inner portion
and the sclerencliymatous wood-cells of the outer one had
their axes parallel to each other as well as to the long axis
of the stem. In the section of Eucalyptus exhibited this
is not the case. The axes of the aggregated wood cells
incline in one lateral direction and those of the vascular
layer in an opposite one ; hence when a section of the stem
of the tree is split vertically these two tissues are seen to
dovetail obliquely into each other in a very singular manner.

Professor Williamson also called attention to some recent
discoveries throwing light upon the two rows of round or
oval scars seen on the stems of the carboniferous genus Ulo-
dendron. Mr. Carruthers long ago expressed his conviction
that these scars marked positions from which serial roots
had been given off. On the other hand Professor W. had
pointed out (Phil. Trans. 1872, pp. 210 — 225) the extreme
probability that these scars had supported cones or strobili
— that conclusion having been based upon the peculiar
manner in which the vascular bundles supplying the scars
were given off from the central vascular cylinder of the
branch or stem. Dr. Dawson of Montreal had arrived at a

95

similar conclusion from a study of the external forms of
these scars. The question has been set at rest through the
discovery, by Mr. D’Arcy Thompson of Edinburgh, of two
specimens in which the cones are preserved in connection
with the scars. Each cone was obviously developed from a
leaf-covered bark, but as it grew in diameter its truncated
base pressed down the neighbouring leaves and thus pro-
duced the well-known large circular areola. The actual
organic connection of the cone and its parent branch was
obviously limited to a small circular areola in the centre of
each scar. After these deciduous strobili fell, the scars
remained permanently impressed upon the bark of the tree.
At first each scar was small and circular, but as the stem
enlarged both in length and diameter the scars underwent
a similar enlargement ; but since the longitudinal growth
of the stem was obviously more rapid than the transverse
one, it necessarily resulted that these originally circular
scars became converted into vertically elongated oval ones.
This change in the shape of leaf-scars resulting from the
direction of growth is well shown in the arborescent stems
of living species of Alsophila. Ulodendron therefore was a
branching Lepidodendroid plant whose branches supported
distichously arranged strobili, the individuals of the two
series being disposed alternately.

96

PHYSICAL AND MATHEMATICAL SECTION.

March 25th, 1879.

E. W. Binney, F.R.S., F.G.S., in the chair.

The following gentlemen were elected officers of the
section for the ensuing year : — -

E. W. BINNEY, F.R.S., F.G-.S.

Hice^presitfcnts.

JOSEPH BAXENDELL, F.R.A.S.

ALFRED BROTHERS, F.R.A.S.

treasurer.

JAMES BOTTOMLEY, D.Sc., B.A., F.C.S.

Secretary.

REY. THOMAS MACKERETH, F.R.A.8., F.M.S.

“ Observations of Dr. Klein’s new Lunar Crater near
Hyginus, made at the Observatory, Birkdale,” by Joseph
Baxendell, F.R.A.S.

In consequence of the conflicting statements which had
been made with reference to the object in the moon near
Hyginus discovered by Dr. Klein on the 19 th of May, 1877,
which he believed to be a new crater; and some observers
having doubted its existence, I took advantage of the fine
night of the 2nd of November, 1878, to turn the telescope
on the moon, which was then in a phase favourable for the
observation of the region of Hyginus, and having Dr. Klein’s
drawing to refer to, I at once saw the object which has been
made the subject of so much discussion and dispute. It
appeared at 6h. 15m. G.M.T. as a round and very dark spot,
and was slightly less black than the shadow in Triesnecker.
With powers 180 and 260 its diameter was estimated to be
about two-thirds that of the crater marked by Dr. Klein
Triesnecker d (Beer and Msedler’s Hyginus a); and in
moments of best vision I received the impression of an
extremely delicate line of light on its eastern border. The

97

tongue-shaped depression towards the south mentioned by
Dr. Klein was also seen, and the two minute craters to the
south-west laid down in his sketch were very conspicuous.
At 6h. 45m. the blackness of the new crater had already

November 3rd, at 5h. 15m. The new crater still appeared
as a dark spot, though not nearly so dark as on the previous
evening.

November 4th. The new crater appeared as an irregular
ill-defined spot, slightly brighter than the surrounding
district.

December 4th, at 8h. Klein’s crater presented the same
appearance as on November 4th.

December 5th, at 14h. 15m. I noted down “Klein’s new
crater is now a moderately bright spot.”

Owing to illness I was unable to observe the moon again
near its first quarter till February 28th, 1879, when at 9h-
30m. the new crater was again seen as a very dark though
not absolutely black spot; but at llh. 30m. it had become
decidedly less dark. A line drawn from the middle of
Triesnecker through the middle of Hyginus and carried
about one-fourth of its length further will fall upon the new
crater, the position of which is also well-marked by a line
drawn from the small crater No. 3 in annexed sketch,

become very much less than that of the shadow in Tries-
necker.

Triesnecker

through No. 2, and continued as far again.

98

March 1st, 7Jh. Klein’s crater well seen with 4in.
aperture. With Gin. aperture it appears smaller and much
less dark than last night. At lOh. the crater is sensibly less
dark since 7|h., and has now an irregular oval shape in the
direction of the small crater No. 1.

March 2nd, 6h. 35m. The crater no longer appears either
as a round or oval shaped spot, but on its place and extend-
ing nearly to the first or No. 1 small crater, to the S.W.
there is a dusky marking but little less bright than the
surrounding district. 7h. 15m. Definition has now become
so bad that it is impossible to make out any of the details
satisfactorily, or even to distinguish the dusky marking.

March 3rd, 9h. 30m. Klein’s crater is not now visible as
either a dark or a bright spot.

March 4th, 9h. There is a moderately bright spot on or
very near the place of the crater; it is less bright than either
of the two small craters to the S.W. Images unsteady, and
observation interrupted by clouds.

March 5th, 12h. There is a faintly bright spot on the
place of the new crater. The order of brightness of Nos.
2, 3, 4 and N (the new crater) is 4, 3, 2, N. N appears to
be elongated, or rudely shaped like the figure 8, in the
direction of crater No. 1.

March 6th, 7h. Klein’s crater is still visible, slightly
brighter than the surrounding ground. Order of brightness
—4, 3, 1, 2, N.

March 8th, 12h. Klein’s crater and the other small craters
very distinctly visible, definition being moderately good.
Order of brightness— 4 = 3, 2, 1, N. A moderately bright
streak from H to N with a faint continuation to a point on
the furrow a little to the east of Hyginus.

I have had no opportunity of observing the moon since
the 8th of March, but the observations up to that date, as
given above, seem to me to remove all doubt as to the
existence of the object which Dr. Klein regards as a new

99

crater. On the supposition that it is not of recent formation,
it seems unaccountable how it could have entirely escaped the
notice of such experienced observers as Schroeter, Lohrman,
Beer and Msedler, Schmidt, Nasmyth, Birt, Neison, Klein, and
others who have devoted so much of their time and attention
to the critical examination and mapping of the moon’s
surface; and I think, therefore, we are entitled, in the
absence of positive evidence to the contrary, to conclude
with Dr. Klein that it is a new appearance, though it may
be doubted whether it is a true crater, as supposed by its
discoverer, or merely a slight subsidence of a portion of the
moon’s surface.

aOn the Meteorological Effects of the position of the
Moon with respect to the Sun,” by Joseph Baxendell,
F.R.A.S.

In a paper “On the Variations of the Daily Range of
Atmospheric Temperature as recorded at the Kew Observa-
toryby Professor Balfour Stewart, F.RS., printed in the
Proceedings of the Royal Society, vol. xxv, p. 577, the author
has shown that the daily range of temperature varies with
the phases of the moon, and that the variations are greater
in the winter than in the summer months, and opposite in
character, the range in the winter being greatest at and
shortly after new moon, and least at and a few days after
the full. The novel and remarkable character of this
result of the Kew observations at once suggested the desira-
bility of discussing the observations made at other stations
with reference to the phases of the moon, though it is evi-
dent that as the daily range of temperature is dependent to
a considerable extent on the greater or less prevalence of
cloud, the direction of the wind, the hygrometric state of
the air, &c., its variations could not in general be the same
at all stations in the same phase of the moon, but that while
at a maximum at certain stations during a given phase it

10 ^

100

would be at a minimum at other stations. Moreover, it
seemed very probable that if the daily range of tempera-
ture is sensibly influenced by the position of the moon with
respect to the sun, other elements, as the amount of cloud,
the mean daily temperature, direction of the wind, &c.,
would also be found to be subject to changes in a period
corresponding to that of the moon’s synodical revolution.
I therefore in the first instance selected for examination the
observations which have been regularly and carefully made
at the Southport meteorological observatory since the 1st of
July, 1871. From the open position of the observatory,
removed many miles from hills or high land, the observa-
tions are less likely to be affected by disturbing influences
than at stations less favourably situated,

The following table shows the mean daily range of
temperature on the days of full moon, and two days before,
and two days after, during the winters of the years 1871-8,
and also the mean daily range on the days of new moon,
and two days before, and two days after, during the same
winters : — -

Winters of

Mean daily Range of Temperature
on days of

Full Moon. New Moon,

Difference.
Full— New.

1871-2

9 ‘09

10-28

- 1*19

1872-3

9*41

8-56

+ 0-86

1873-4

8-05

9-21

-IT 6

1874-5

10-35

9-96

+ 0-39

1875-6

9-37

8-39

+ 0-98

1876-7

11-58

9-08

+ 2-50

1877-8

9-66

9-33

+ 0-33

Means

9-64

9-26

+ 0-38

It appears, therefore, that at Southport during the winter
months the daily range of temperature is on the average
greater on the days of full moon than on the days of new
moon, a result the reverse of that derived by Dr. Stewart
from the Kew observations, and confirming the view stated

101

above that the maximum range cannot take place at all
stations in the same phase of the moon.

Estimations of the amount of cloud are made and recorded

at 9 a.m., 1 p.m., and 9

p.m. daily. I have therefore tabu-

lated the amounts of cloud at the times of full and new
moon during the six winter months on the plan adopted
with the daily range of temperature, and have obtained the

following mean results :

1871-2

Mean Amount of Clouds at 9 a.m.
on days of

Full Moon. New Moon,

7-7 7-1

1872-3

6*3 7-4

1873-4

7-2 7-5

1874-5

6-9 7-6

1875-6

7-9 7-5

1876-7

7-7 8-4

1877-8

8-0 7*9

Means

7-38 7-63

Mean Amount of Cloud at 1 p.m,
on days of

1871-2

Full Moon.

7*2

New Moon.
6-0

1872-3

6-5

6-3

1873-4

6-9

7-9

1874-5

... 6 *6

7-0

1875-6

7-7

7-2

1876-7

7*9

8-3

1877-8

7-5

7-3

Means

7-19

7-14

1871-2

Mean Amount of Cloud at 9 p.m.
on days of

Full Moon. New Moon.

6-3 5-9

1872-3

6*2

5-9

1873-4

6-2

5-4

1874-5

7-1

4-8

1875-6

6-6

5*7

1876-7

8-0

6 6

1877-8

7-5

7*1

Means

6-84

5-91

102

It appears, therefore, that at 9 a.m. the mean amount
of cloud is slightly greater on days of new moon than on
days of full moon ; at 1 p.m. the amounts are sensibly equal,
but at 9 p.m. the amount on days of full moon is greater
than on days of new moon. It will also be seen that while
on days of full moon the mean diminution in the amount of
cloud between 9 a.m. and 9 p.m. is (bo 4 ; on days of new
moon it amounts to 1*72.

It has been supposed by Sir John Herschel and other
meteorologists that the full moon had the effect of partially
dispersing the clouds, but the above results show very clearly
that any effect which the moon may have is of an opposite
character, as in every winter the mean amount of cloud was
greater at the time of full than of new moon.

The observations of mean daily temperature at the times
of full and new moon have yielded the following results

Mean Daily Temperature
on days of

Full Moon. New Moon.

1871-2

44-3

43-4

+ 0-9

1872-3

40-3

43-0

-2-7

1843-4

45-4

46-0

-0-6

1874-5

41-6

41-9

-0-3

1875-6

38-2

43-5

-5-3

1876-7

43*7

45-4

-1-7

1877-8

45-9

44*5

+ 1-4

Means . . .

42-77

43-96

-1-19

The days of the full moon were therefore on the average
1T9 colder than the days of new moon. This result led
me to infer that at the times of full moon northerly winds
had been more frequent than at the times of new moon.
Observations of the direction of the wind are made at 9 a.m.,
1 p.m., and 9 p.m. daily ; and as the velocity of the wind is
generally greatest about 1 p.m., its general direction can be
more accurately determined at that time, and therefore a
table was formed, showing its direction at 1 p.m. on the
selected days at the times of full and new moon during the

103

winter months of the seven years, and the following results
were obtained : —

From the

Wind Frequency at the Times of
Full Moon. New Moon.

Difference.
Full— New.

N.E quarter.

35 days.

18 days.

+ 17

S.E. do.

61 do.

84 do.

-23

S.W. do.

62 do.

82 do.

-20

N.W. do.

52 do.

26 do.

+ 26

At the times of full moon the winds were from the N.E.

and N. W. quarters on 87 days, but at the times of new moon
on only 44 days, thus confirming the conclusion to which I
had been led by the results of the temperature observations.

A similar grouping of the direction of the wind at 1 p.m.
on the days of first quarter of the moon and two days before,
and two days after; and also on the days of last quarter,
and two days before and two after, gave the following
results

Difference.

N.E. quarter.

Wind Frequency at Times of
First Quarter. Last Quarter.

18 days. 25 days.

Last Q,r.—
First Qr.

+ 7

S.E.

do.

70 do.

70 do.

0

S.W.

do.

74 do.

66 do.

-8

N.W.

do.

48 do.

46 do.

-2

Calm

0

3

+ 3

From these two tables of wind frequency we find that
the relative frequency of northerly and southerly winds at
1 p.m. during the winter months under the different phases
of the moon is as follows : —

Frequency of Ratio of Southerly to

Northerly Southerly Northerly

Winds . Winds. Winds.

New Moon 44 days.
First Quarter 66 do.
Full Moon 87 do.
Last Quarter 71 do.

166

days.

3-77

144

do.

2-18

123

do.

1*41

136

do.

1*91

These numbers show that northerly winds are least
frequent at and a little after new moon, and most frequent

at and a little after full moon. On the other hand southerly
winds are least frequent under the full moon, and most

frequent under the new moon.

Taking now the observations of the direction of the wind
made at 9 p.m. we obtain the following results : —

104

Frequency of

Northerly Winds Southerly Winds
at 9 p m. at 9 p.m.

New Moon 43 days. 162 days.

First Quarter 65 do. 138 do.

Full Moon 89 do. 116 do.

Last Quarter 75 do. 128 do.

Ratio of Southerly to
Northerly
Winds.

3-76

2-12

1-30

1-70

The differences between the numbers in the last column
of each of these two tables are so great that it seems
impossible to doubt that the position of the moon with

respect to the sun exercises in some way an influence upon
the direction of the wind, and that this is the case is further
supported by the fact that in each winter the frequency of
northerly winds under the full moon and last quarter was
greater than under the new moon and first quarter, as will
be seen from the following numbers

Northerly Winds at 1 p.m. and 9 p.m. under
New Moon and Full Moon and
First Quarter. Last Quarter.

21 49

36 56

30 37

34 52

40 57

26 39

31 32

1871- 2

1872- 3

1873- 4

1874- 5

1875- 6

1876- 7

1877- 8

These numbers also indicate that the frequency of
northerly winds under the full moon and last quarter, as
compared with that under the new moon and first quarter,
has gradually diminished during the seven years. Thus
taking groups of three winters each, we have the following
mean ratios

1871-2 to 1873-4 the mean ratio is ... 1/63

1873-4 to 1875-6 do. do. ... 1*40

1875-6 to 1877-8 do. do. ... 1-32

Assuming that this diminution is due to the gradual
diminution of solar activity which has been going on during
the seven years we may expect that the ratio will be at a

minimum during the present winter.

The widely different character of the action of the moon
upon the direction of the wind during the summer months

of the seven years will be seen from the following results : —

Frequency of

Northerly Winds. Southerly Winds. Ratio of Southerly
lp.m. 1p.m. to Northerly Winds.

New Moon ... 89 ... 123 ... 1-38

Full Moon ... 84 ... 131 ... 1*56

The ratio of southerly to northerly winds is therefore
slightly less under the new than under the full moon in the
summer months, but in the winter months, as we have
already seen, it is much greater.

OXFORD OBSERVATIONS.

As the influence of the moon appeared from the South-
port observations to be shown more clearly by the direction
of the wind than by the daily range of temperature, the
amount of cloud, or the mean daily temperature, the
observations of the wind made at the Badcliffe Observatory,
Oxford, during the ten years 1865-75 were tabulated on the
plan I had adopted with the Southport observations, though
it must be remarked that the directions of the wind given
in the published “ Observations” are not for any particular
hour of the day or night, but are the estimated mean direc-
tions for the 24 hours. It was considered, however, that
this difference would have no material effect upon the
final results. The following table shows the frequency of
northerly winds under full moon and new moon during the
ten winters 1865-6 to 1874-5 : —

1865- 6

1866- 7

1867- 8

1868- 9

1869- 70

1870- 1

1871- 2

1872- 3

1873- 4

1874- 5

Frequency of Northerly Winds under
Full Moon. New Moon.

12

14

14
17
21
11
13
19

8

15

6

12

7

14

13

14

5

5

6

8

144

- Totals . , .

90

106

It will be seen that in every year except one the frequency
under the full moon was greater than that under the new
moon, and that the total frequency of the ten winters was
144 under the full moon and only 90 under the new moon.
These results of the Oxford observations are therefore in
very satisfactory accordance with those of the Southport
observations, and give strong support to the view that the
direction of the wind is in some way influenced by the
position of the moon with respect to the sun. Should this
view be confirmed by the results of observations made at
other stations it will evidently be very desirable to examine
the directions in which the centres of cyclones and anti-
cyclones move across our coasts, during the winter months,
under different phases of the moon.

MICROSCOPICAL AND NATURAL HISTORY SECTION.

February 10 th, 1879.

Thomas Alcock, M.D. in the chair.

Mr. Charles William Kimmins, Mr. Sydney Young, and
Mr. Marcus Manuel Hartog, B.Sc., F.L.S., all of Owens
College, were elected Associates of the Section,

107

Mr. Charles Bailey, F.L.S., gave an account of the
germination of ferns, with diagrams.

Mr. M. M. Hartog, F.L.S., described the anatomy of
the fresh water mussel (Anodonta Cygnea (L).)

March 10th, 1879.

A. Brothers, F.R.A.S., in the chair.

Mr. S. Moore exhibited a curious white growth, probably
attributable to spores of a species of Polyporus, covering
beech trees in Derbyshire.

Mr. Rogers exhibited rings from the scales of cuttle fish
(Loligo), brought up abundantly by two tides only at
Barmouth, in 1874, collected by Mr. R. M. Christy.

Mr, John Plant, F.G.S., read a paper upon “The Great
Sheatfish, Silurus glanis, in Loch Bad-a-Luacradh, Ross.”

The author gave a sketch of the natural history of the
family of the Siluridse, which includes about a dozen known
species, one of which the S. glanis inhabits some of the great
rivers of Europe and a few of the lakes. It is most abundant
in the Danube, Volga, and the Rhine, and is known in the
largest streams which fall into the Baltic, being also at times
caught in the upper regions of the Baltic, where the water
is but slightly brackish. It has been obtained from Lakes

108

Neuchatel, Brienne, and Morat, the species is also found in
North American lakes and some rivers.

The Sheatfish grows to an enormous size in waters favour-
able to its mode of life. Specimens weighing 700 lbs. are
recorded from the Danube, and in America, the average size
of the adult fish is about 300 lbs. The bulk of the fishes
caught in the season are of less weight, The length of ex-
ceptional specimens will reach to 20 or 22 feet ; but 8 or 10
feet are the lengths of large specimens.

The general appearance of the Sheatfish is like that of a
bulky eel, the eyes are large and froglike. The head is
unpleasant to look at, and the mouth wide — the upper lip
is armed with two long wormlike feelers, or barbules, which
are kept in active motion either as sensitive organs of
feeling, or to seize frogs and small fish which come
within their reach. Its habits are to hide in the muddy
bottoms or amongst the roots of aquatic vegetation— only
coming to the surface on hot sunny days, after thunderstorms
or when the water is frozen over— to keep an air hole open
for occasional fresh air breathing.

It has been attempted twice to introduce its spawn or
young fish in English rivers, both trials have failed,
although it is a hardy fish and very tenacious of life. The
flesh of the Sheatfish is largely eaten in the countries where it
abounds, but accounts differ as to its flavour and qualities.
At one time in season it resembles fine fresh salmon in
flavour, at another time white, fat, soft, luscious and not
easy to digest. In the restaurants in the towns along
the Danube, the Sheatfish is cooked in so many ways that a
traveller may dine altogether upon this fish, and fancy he
has been served with a variety of soups and meats.

Whether the Silurus was ever, or is now, native to
British rivers and lakes is as yet an open question, the
peculiar spine which supports the pectoral fin has been dug
from deposits in the London clay, i.e., Eocene , and Mr.

109

Higgins, of Liverpool, found one of these spines in clay
under a bed of peat at Leasowes, on the banks of the river
Dee. So far it may have lived in English rivers at more
remote times.

In 1828 a fish was caught in a river at Florence Court,
Ireland, which was satisfactorily proved a long time after-
wards by the Earl Enniskillen and Professor Louis Agassiz
to be a Silurus glanis — not a fragment of the fish or its
skeleton was preserved, which was unfortunate, as its
identification depended upon memory alone and its re-
semblence to a drawing of Silurus.

Dr. Fleming notices a remark by Sibbald, that the Silurus
may have been seen in the Scotch rivers in his day.

The author then stated : “ Several years ago I received a
letter from a gentleman residing in the highlands of Ross
describing an extraordinary monster which had been
occasionally seen by his servants and tenants floating on
the waters of Loch Bad-a-Luacradh—~Lake of the Rushes—
near the coast about Loch Eu. The people called the monster
a Snail Whale; it seemed about 22 feet in length, and had
two flexible horns on its mouth ; it was fond of basking on
the surface of the water, particularly after great storms, and
looked very much like a herring boat turned keel upwards.
In reply I sent a drawing and description of Silurus
glanis, which was at once recognised by all the people
who had seen the big monster as a capital portrait of it.

Efforts were repeatedly taken to capture the monster by
nets, by baiting, and by shooting, but without success, and for
three winters similar endeavours to capture it equally failed.
It was ascertained by strict inquiry amongst the native
residents, that the fish had been seen as far back as sixty
years ago, when it was much smaller. An old shepherd
had seen it first, a very old dame saw it thirty years ago, a
smuggler or illicit whiskey distiller who had a bothy hard
by the loch often saw the monster in the quiet hours of

110

morn, he did not like the uncanny beast as a neighbour
at all. Many other witnesses who gave similar evidence
were mentioned by the author, who as well described the
methods adopted to capture the monster, but after much
trouble and expense it proved too wary and alert to be
captured or even to be shot, and the enterprise had to be
abandoned. Probably the monster died, or escaped from
the loch.

Ill

Ordinary Meeting, April 15th, 1879.

J. P. Joule, D.C.L., LL.D, F.RS., &c., President, in the

Chair.

“ Mineralogical Notes,” by Charles A. Burghardt,
Ph.D., the Owens College.

Precious Garnet (Almandine) from Ramsbottom ,

Lancashire .

A few days ago I received a small specimen of rock from
a former pupil of mine (Mr. J. F. C. Sieber) accompanied
by a note, in which the writer gave particulars respecting
the locality in which the rock was found, and asked me to
examine certain red granules present in the rock in order
to ascertain whether they were garnets or not. The rock
itself is a conglomerate of milky quartz grains (varying
considerably in size), cemented together with silica and
calcium carbonate ; and disseminated throughout this con-
glomerate are the garnet grains in question, the whole con-
stituting a 14 feet “ fault” in the coal seam known as the
Sand-rock or Featheredge Seam in the “ SKipperbottom
Mine,” near Grant’s Tower at Bamsbottom, The coal from
this mine is accompanied by a shale, which contains a very
considerable amount of sulphate of aluminium, as it efflo-
resces on being exposed to the action of the air ; becoming
eventually perfectly white like a piece of chalk. A micro-
scopical examination of the rock showed the garnets to
Proceedings — Lit. & Phil. Soc. — Yol. XVIII,— No. 11. — Session 1878-9.

112

be very irregular in form and to vary considerably in
size, tlie largest attaining a width of about 2 ’2 5 mm. and
the smallest about 075 mm. They exhibited no distinct
crystalline form, but a peculiar indented appearance was
observed on the surfaces of some individuals, whilst others
were pebblelike, somewhat convex and rounded off as though
they had been mechanically acted upon by water. The quartz
grains did not exhibit the slightest trace of crystalline form
but were rounded off and pebble-like. Both the garnets
and the quartz grains could be extracted from the matrix,
a cast of their forms being left behind. The red grains
fused easily and quietly before the blowpipe to a black
bead, which was not however magnetic ; they were some-
what attacked by hydrochloric acid with a slight separation
of powdery silica : the presence of iron was also detected.
The hardness of the mineral was 7'5, and its specific-
gravity 4’09 at 9°C. I hope shortly to determine the
chemical composition. A microscopical examination of
the garnet grains showed them to be crystalline, exhibiting
certain marked peculiarities, and after a careful examina-
tion of many of them I came to the conclusion that the
form in which they crystallised was the rhombicdodeca-
hedron. I had previously proved them to be crystals
of the regular system by examining the grains in polarised
light and finding them to be isotropic. The crystals were
built up out of myriads of minute laminated abnormal
rhombicdodecahedrons, two faces of which have been enor-
mously developed at the expense of the other faces.
These laminae are arranged parallel with each other in posi-

113

tions corresponding to each face of a rhoinbicdodecahedron,
the indentations observed upon the indistinct crystal faces
of some individuals being caused by this peculiar laminated
growth. The laminae vary from 0-0282 mm. to 0-1880 mm.
in length, from 0-0188 mm. to 0-1504 mm. in width, and
from 0 0031 mm. to 0‘0045 mm. in thickness. I have en-
deavoured to give some idea of the appearance exhibited by
these laminae when examined under the microscope in the
drawing appended.

GARNET LAMINiE FROM RAMSBOTTOM.

The colour of the garnets (for such the crystals undoubt-
edly are) is light rose-red, and coupling this with their
transparency and chemical properties there can be no doubt
that they are alumina-iron garnets, or almandine. On exa-
mining some of the laminae under the microscope I observed
that they contained enclosures, which were mostly fluid cavi-
ties or “ gaspores,” also here and there cracks and rifts, filled
with a white substance which most probably was calcite. On
some of the laminae there was a separation out of a greenish
mossy substance, which I believe to be ferric oxide, and on

114

one individual I observed a few specks of iron-pyrites. It
is somewhat difficult to draw a conclusion as to the origin
of these garnets in such a locality. From the macroscopical
examination of the rock it would appear that the cement
and the garnets were both in a soft and pasty condition,
the latter being probably formed whilst in the pasty matrix
and prevented from attaining a normal development. It is
a well known fact that crystals which have formed in a free
space or in a liquid mass which has not exerted any retard-
ing influence upon the force of crystallisation, always exhi-
bit well defined faces and angles, whilst the opposite condi-
tions result in abnormal growths such as the garnet crystals
just referred to. The quartz grains were probably formed
previously to the garnets, as they appear to be water-
worn pebbles, and were most likely carried along with the
semi-paste-like mass which contained the constituents of
garnet and calcite in its substance. When the paste hard-
ened, the quartz grains and the garnets were enclosed in the
manner exhibited on the specimen of rock from Ramsbottom.
All the constituents of garnet were at hand, namely, alumi-
nous shale, which would furnish the alumina and silica, and
iron-pyrites, which would furnish the iron, whilst water
impregnated with calcium carbonate, acting upon the shale
and iron-pyrites, would bring about the necessary chemical
changes, calcium sulphate being formed and carried away
and the garnet solution (if such a term may be used) could
then crystallise out. From the formation and the locality
in which the garnets were found it is quite certain that
their origin was aqueous. Another explanation of the

115

occurrence of garnet in the conglomerate may be as follows,
viz. : garnet is a very common accessory of crystalline rocks,
occurring mostly in slates of various kinds, such as talc-
slate, mica-slate, chlori tic- slate, and aluminous-slate; it
also occurs in gneiss, granite, porphyry, serpentine, and
granular limestone. One or more of the above-mentioned
rocks containing crystallised garnets already formed, were
disintegrated by the action of water, and the resulting
debris (consisting of grains or pebbles of quartz and garnets)
was carried away and deposited in a semi-fluid mass of silica
and cal cite and thus cemented together. The question
which next arises is, where and what is the original garnet
rock in the neighbourhood of Ramsbottom ; is it perhaps
the aluminous shale ? This problem still remains to be
worked out. It is evident however at once on examining
the conglomerate that there is a large excess of quartz
grains present, with a very fair sprinkling of garnets •
whilst the cement is not present in any great amount. An
examination of thin sections of this rock under the micro-
scope may clear up some doubts, and throw further light
upon its origin.

Fibrous Roch-Scdt (Sodium Chloride).

This anomalous formation has always been an interesting
one, on account of the strong cubical “ habit” of rock-salt,
all other forms than that of a well-defined cube heino* rari-

O

ties. The fibrous formation is not due to a crystallisation
of the sodium chloride in another system than the regular
system, but is explained by an abnormal development of
four cubical faces parallel to one axis, which may with pro-

116

priety be called the prismatic axis. So far as I am aware,
the formation of fibrous rock-salt has not been explained.
Having the well known fact before me, viz., “ the influence
exerted upon the crystal form of a body crystallising out
of its solution by the presence in that solution of a small
quantity of a foreign body,” I thought it probable that a
similar effect might be produced upon the growth of sodium
chloride crystals by the presence of a foreign body or
bodies. In order to ascertain this I made a strong saturated
solution of ordinary table-salt, filtered it, and precipitated
out most of the salt by passing hydrochloric acid gas into
the solution. The liquid was drained off from the preci-
pitated salt and allowed to evaporate very slowly for several
days in a narrow-necked flask and then laid aside to cool'
I then observed amongst the mass of ordinary salt cubes
numerous long, well-developed prisms. Some of these
prisms were an inch or more in length and sometimes ter-
minated by a broad cube; others again were twinned
according to the usual law, viz., “the twin plane a face of
the octoliedron.” I observed that many of the cubical
crystals were somewhat bent and resembled closely the bent
barytes crystals of the prism and basal terminal plane in
combination. Nearly all the crystals (prismatic and cubical)
were opaque or almost so, and of a very white colour. In
addition to free hydrochloric acid, I found in the solution a
quantity of magnesium sulphate and magnesium chloride,
and it is to the peculiar retarding action of these substances,
either together or singly, that I ascribe the general forma-
tion of fibrous rock-salt ; for they could easily occur natu-

117

rally in any rock-salt formation. As sulphate of magnesium
and chloride of magnesium are constituents of sea- water
and generally present in all waters flowing from rocks,
either crystalline or sedimentary, their presence during the
deposition of rock-salt is ensured, whilst the presence of
hydrochloric acid would also he possible if a slight rise of
temperature took place during the deposition, it being a fact
that magnesium chloride gives off hydrochloric acid during
evaporation at comparatively low temperatures.

In the discussion which followed the reading of the above
paper Mr. Binney, F.B.S., read an extract from Trans.
Man. Geol. Soc., Yol. I., p. 87, to the following effect, viz. —

“On the Marine Shells found in the Lancashire Coal
Fields, by E. W. Binney.

“ Immediately above the ‘ Bough rock’ at Birtle Dean,
near Hey wood, is the Featheredge coal, about two feet
thick ; this seam has a roof of one yard in thickness, con-
sisting of black shale which is full of the Pecten, Goniatites,
Povidonia, &c., mixed with various species of Ferns, Lepido-
dendra, and Sigillarise. It is a singular fact that the black
shale has scarcely ever been seen on the roof of this coal,
except at Messrs. Bamsbottom’s colliery, at Birtle Dean. At
Fecit, within two miles of the last named place, and other
localities, the roof of the coal consists of a coarse conglomerate
of quartz pebbles, containing numerous garnets and crystals
of carbonate of barytes, generally presenting a water-worn
appearance. I have also observed small pieces of opal im-
bedded in this rock,”

118

E. W. Binney, F.R.S., V.P., exhibited a gigantic tooth of
a fossil shark found in making the railway between Seville
and Cordova in Spain. The age of the deposit in which it
was found is not clearly ascertained, but it is probably
Older Pleiocene. It is the largest that he ever heard of.
Neither the very large specimen in the Hunterian Museum,
London, from Malta, nor any in the numerous public mu-
seums or private collections in England, equal that shown.
Its dimensions are 6J inches in perpendicur height and 4J
inches in breadth, and 10 inches in girth at its base. It
is in a most beautiful state of preservation, nearly as per-
fect as it was in the living fish, and probably belonged to
Cavckarias vulgaris or some allied species.

119

Annual General Meeting, April 29th, 1879.

J. P. Joule, D.C.L., LL.D, F.R.S., fee., President, in the

Chair.

Report of the Council , April, 1879.

The annual statement of the Treasurer appended to this
report shows that the expenditure of the Society during the
year ending 81st March last, has considerably exceeded the
income, owing principally to an unusually heavy outlay for
books and book-binding. The balance against the General
Fund Account has increased from £10 14s. 4d. to £113 Os.
lid. There is also a balance of £3 9s. Id. against the
Natural History Fund Account ; and deducting these two
sums from the Compounders’ Fund, £125, there is a balance
of £8 10s. in favour of the Society on the 1st of April,
1879.

The number of ordinary members on the roll of the Society
on the 1st of April, 1878, was 157, and eight new members
have since been elected : the losses are- — deaths 2 : resign-

' o

ations 2 ; defaulter 1. The number on the roll on the 1st
instant was 160. The deceased members are Mr. Thomas
Livesey aud Mr. James Me. Connell. Since the above-

mentioned date notice has been received of the death of
Mr. Robert Stuart, the oldest member of the Society, he
having been elected on January 21st, 1814.

It was stated in the last annual report that the N atural
History Fund of £1500, presented by the late Natural His-
tory Society, had been received from the Trustees of the
Owens College by' the Treasurer, and that the Council had
given instructions for its investment in any of the stocks or
Proceedings— Lit. & Phil. Soc.— Yol. XYIIL— No. 12— Session 1878-9,

120

securities authorised by the trust deed. In accordance with
these instructions the Fund has since been invested in
Great Western Railway 5 per cent Preference Stock.

Since the last annual meeting three valuable portraits
have been presented to the Society — the first a portrait of
Dr. Percival, the first President of the Society, painted by
Crozier, and presented by the Hon. Librarian, Mr. Nichol-
son; the second a portrait of the late Professor Eaton
Hodgkinson, painted by Duval, and presented by Sir
Thomas Fairbairn, Bart. ; and the third a portrait of Mr.
Binney, F.R.S., painted by Mr. William Herbert Johnston,
and presented by the President, Dr. Joule, F.R.S. A valu-
able engraving of the late Mr. J. C. Dyer has also been
presented by Mr. Nicholson.

In consequence of an application from the Geological
Society for increased accommodation for their Library, the
following arrangement was agreed to by the Council on the
7th of January last : — “That the Geological Society should
have shelf space given them in the Entrance Hall on both
sides ; that they should remove the inner door, moving the
outer door at their expense, and make good all damages
done by the alterations ; that they should have storing in
the cellar for their Proceedings ; that the members of the
Geological Society shall have the use of the Council Room
at ail times when it was not occupied by the Council or by
Committees, and that they should make an annual donation
to the housekeeper for sending out their circulars.”

At a meeting held on the 15th of October, 1878, the
Council resolved “That Associates of Sections be empowered
to vote for the election of officers of the Sections, such offi-
cers being members of the Society.”

As the centenary of the Society will occur in February,
1881, it will be for the new Council to consider and decide
upon the steps which it may be thought desirable to take
for its formal celebration.

The following papers and communications have been read
at the Ordinary and Sectional Meetings of the Society
during the session : —

October 1 bth, 1878 — “On a Eucalyptus globulous,” by E. W.
Binney, F.R.S., F.G.S.

“ Relative Brightness of the Planets Venus and Mercury,” by
James Nasmyth, C.E., F.R.A.S., Corresponding Member of the
Society.

“ On the Water of Thirlmere,” by Harry Grimshaw, F.C.S., and
Clifford Grimshaw.

October 29 th, 1878. — “Note on certain Thionates,” by E, J.
Be van, Student in the Owens College. Communicated by Professor
H. E. Roscoe, F.R.S., &c.

“The Use of the Opercula in the Determination of the Cheilo-
stomatous Bryozoa,” by Arthur Wm. Waters, F.G.S.

“On some Improved Methods of Producing and Regulating
Electric Light,” by Henry Wilde, Esq.

November 4 th , 1878. — “An Account of three visits to the
Breidden Hills, Montgomeryshire, North Wales, in May, June, and
July, 1877,” by J. Cosmo Melvill, F.L.S.

November 12th , 1878. — “Remarks on a Fossil Plant found at
Laxey, in the Isle of Man,” by E. W. Binney, F.R.S., F.G.S.

November 2 6th, 1878. — “On some Improved Methods of Pro-
ducing and Regulating Electric Light,” Part II, by Henry Wilde,
Esq.

December 2nd , 1878.— “A Preliminary Abstract of an Investi-
gation of the Nervous System of Cyclops,” by Marcus M. Hartog,

F.L.S.

December 10 th, 1878. — “On the Combinations of Aurin with
Mineral Acids,” by R. S. Dale, B.A., and C. Schorlemmer, F.R.S.

“ On the Estimation of Small Excesses of Weight by the Balance
from the Time of Vibration and the Angular Deflection of the
Beam,” by J. H. Poynting, B.A., B.Sc.

December 24 th, 1878. — “Note on the Intensity of Moonlight,” by
Harry Grimshaw, F.C.S.

January *lth, 1879. — “On Boulders of Clay from the Drift,” by
E. W. Binney, F.R.S., F.G.S.

122

January 8th, 1879. — 1 “ On Specimens of Ballast Plants collected
at Cardiff in September, 1878,” by Mr. Thomas Regers.

January 21^, 1879. — On an old Letter of the late Sir Walter
Scott,” by E. W. Binney, V.P., F.R.S., F.G.S.

“ On a further Analysis of the Water of the Mineral Spring at
Humphrey Head,” by C. Grimshaw and H. Grimshaw, F.G.S.

January 2 8th, 1879.— “On a Copy of the Principia of Newton,”
by James Bottomley, B.A., D.Sc.

February 4 th, 1879.—' “ The Area of the Middle Drifts, as deter-
mined by their Contents,” by Alfred Bell, F.G.S. Communicated
by R. D. Darbishire, F.G.S.

February 18^, 1879. — “On a Chemical Investigation of Japanese
Lacquer, or Urushi,” by Sadamu Ishimatsu. Communicated by
Professor Roscoe, F.R.S.

“ On the Bursting of the Gun on board the Thunderer,” by
Professor Osborne Reynolds, F.R.S.

February 25th, 1879. — “On the Mean Temperatures of the
Winters of the last 29 years,” by the Rev. Thomas Mackereth,
F.R.A.S. Ac.

March 4 th, 1879. — “On a Modification of Bunsen’s Calorimeter,”
by Professor Balfour Stewart, LL.D., F.R.S.

“The Poisonous Qualities of the Yew,” by William E. A. Axon,
M.R.S.L., F.S.S.

March 10th, 1879. — On the great Sheatfish, Silurus glanis, in
Loch Bad-a-Luacradh, Ross,” by John Plant, F.G.S.

March 18 th, 1879. — On Siliceous Fossilization,” Part II., by
J. B. Hannay, F.R.S.E., F.C.S.

March 25tli, 1879. — “Observations of Dr. Klein’s new Lunar
Crater near Hyginus, made at the Observatory, Birkdale,” by
Joseph Baxendell, F.R.A.S.

“ On the Meteorological Effects of the Position of the Moon with
respect to the Sun,” by Joseph Baxendell, F.R.A.S.

April 1st, 1879. — Two Deductions from Mr. G. H. Darwin’s
letter in Nature, February 6th, 1879, upon Sir W. Thomson’s
equation of cooling

e clz

by Mr. James Heelis,

o

123

“ Arrangement of a Tangent Galvanometer for lecture-room
purposes, to illustrate the laws of the action of currents on
Magnets, and of the Resistance of Wires,” by J. H. Poynting, B.A.,
Demonstrator in the Physical Laboratory of the Owens College.

“On Aurin, Part II,” by R. S. Dale, B.A., and C. Sehorlemmer,
F.R.S.

“Screw Propulsion,” by Robert Rawson, Assoc. I.N.A., Hon.
Member of the Manchester Literary and Philosophical Society,
Member of the Mathematical Society.

“ On a Section of the Eucalyptus Globulous,” by Professor W.
C. Williamson, F.R.S.

“ On the Oval Scars on the stems of the Carboniferous genus
Ulodendron,” by Professor W. C. Williamson, F.R.S.

The printing of Volume VI., third series, of the Society’s
Memoirs has been completed, and several of the above
papers have been passed by the Council for printing in a
new volume.

The Council still consider it desirable to continue the
system of electing Sectional Associates, and a resolution on
the subject will again be submitted at the annual meet-
ing for the approval of the members.

The Librarian reports that the binding of the books is so
far completed, that not much more money will be required,
except for binding the periodicals as the current volumes
are completed.

The number of Societies we correspond with is the same
as last year, and no books of special interest have been
added to the library.

On the motion of Mr. A. Brothers, seconded by Dr.
James Bottomley, the Report was unanimously adopted,
and ordered to be printed in the Society’s Proceedings.

On the motion of Mr. R. S. Dale, seconded by Mr. H.
Grimshaw, it was resolved unanimously : — That the system
of electing Sectional Associates be continued during the
ensuing Session.

124

On the motion of Mr. E. W. Binney, seconded by Mr.
R D. Darbishire, it was resolved : — That as the Centenary
of the Society will occur in February, 1881, it be referred
to the Council to consider the best means of celebrating it.

On the motion of Mr. R D. Darbishire, seconded by
Mr. E. W. Binney, it was resolved : —

That the Society has heard with great satisfaction that
the Governors of Owens College have requested the Council
to prepare plans for buildings for a Museum of Natural
History.

It would respectfully urge on the College the great
importance of completing such buildings with the least
possible delay, because, as long as the College defers its
performance of the duty which it has undertaken in this
respect, the study of Natural History in this district, where
its various branches are now pursued with great diligence
by many able students, suffers under serious interruption
and disadvantage.

O

It would remind the College that it has long been a
matter of great disappointment and regret, that with such
collections stored up as are now laid by in its rooms, and
with a public so well qualified to appreciate the opportunity,
and while so large an endowment has been accepted by the
College towards the support of a public Museum under
proper scientific and educational conditions, the needful
arrangements should have been so long postponed.

That the President be requested to forward a copy of the
foregoing resolution to the Treasurer of the Owens College
in the name of the Society.

125

The following gentlemen were elected officers of the
Society and members of the Council for the ensuing year: —

■prestocnt,

JAMES PRESCOTT JOULE, D.C.L., LL.D., E.R.S., P.C.S.

Drict='prcstocnts.

EDWARD SCHUNCK, Ph.D., F.R.S., F.C.S.

EDWARD WILLIAM BINNEY, F.R.S., F.G.S.

HENRY ENFIELD ROSCOE, B.A., Ph.D., F.R.S., F.C.S.
ROBERT ANOUS SMITH, Ph.D., P.R.S., P.C.S.

Secretaries.

JOSEPH BAXENDELL, F.R.A.S.
OSBORNE REYNOLDS, M.A,, F.R.S.

treasurer.

CHARLES BAILEY, P.L.S.

Hatiranar.

FRANCIS NICHOLSON, F.Z.S.

©tfjrr Jttemfcers of t!)c ^Council.

REY. WILLIAM GASKELL, M.A.

ROBERT DUKINFIELD DARBISHIRE, B.A., F.G.S.
WILLIAM BOYD DAWKINS, M.A., F.R.S,, F.G.S.
BALFOUR' STEWART, LL.D., F.R.S.

CARL SCHORLEMMER, F.R.S.

JAMES BOTTOMLEY, B.A., D.Sc., F.C.S.

MANCHESTER LITERARY AND

Charles Bailey, Treasurer, in account with the Society

Statement oe the Accounts

1878. — April 1.

To Cash in hand ...

1879. — March 31.

To Members’ Contributions : —

Arrears, 1877-8, 4 at £2 2s

New Member’s Admission, 1877-8, 1 at £2 2s.
j> >, 1878-9, 6 at £2 2s.

,, Half Subscription, 1877-8, 1 at £1 Is.

,, Subscription, 1878-9, 6 at £2 2s

Old Members, 1878-9, 136, at £2 2s

1878-9.

£ s. d. £
1726

8 8 0
2 2 0
12 12 0
110
12 12 0
285 12 0

To One Compounder

To Two. Associates’ Sub. (for Library) 10 0

To Sectional Contributions, 1878-9 : —

Physical and Mathematical Section 2 2 0

Microscopical and Natural History ditto 2 2 0

To Use of Society’s Booms to 31st March,

1878 : —

Manchester Geological Society 30 0 0

Manchester Scientific Students’ Associa-
tion 22 0 0

Manchester Field Naturalists’ Society 9 0 0

To Sale of Society’s Publications

To Natural History Fund : — -

Dividends on £1225 Gt. Western Stock...
To Capital Fund : —

Natural History Society’s Donation..

322

5

61

2

60

To Bank Interest, less Bank Postage, to 31st

December, 1878 10

1877-8.

s. d. £ s. d. £ s. d

4 3 247 19 9

7 0 332 17 0

26 5 0

10 0

2 2 0
2 2 0

4 0 — — 5 4 0

30 0 0

11 10 0

0 0 - 41 10 0

1 10 2 10 0

13 68 16 9

1500 0 0

1568 16 9

17 4 11 10

£2186 19 11

£2229 14

4

Compounders’ Fund : —

Balance in favour of this Account, April 1st, 1879 .. ..
Natural History Fund

Balance, April 1st, 1878

Dividends as above, in 1878-9

£ s. d. £

1611 18 7
. 60 1 3

s. d. . £ s.
125 0

d.

0

:

Expenditure on this Account, 1878-9

Balance against this Account, April 1st, 1879..
General Fund : —

Balance against this Account, April, 1st, 1878

Expenditure, 1878-9, as above

1671 19 10
1675 8 11

9

9 1

o

10 14 4
503 1 0

Keceipts, 1878-9, as above

513 15 4
400 14 5

Balance against this Account, April 1st, 1879 ... 113 0 11 116 10 0

Balance in favour of the Society

£8 10 0

PHILOSOPHICAL SOCIETY.

from 1st April, 1878, to 31st March, 1879, with a Comparative

for the Session 1877-1878. Q£x.

1878-

•9.

1877-8.

1879. — March 31.

£ s.

d.

£ s.

d.

£ s.

d.

£

s.

d.

By Charges on Property : —

Chief Rent

12 13

6

12 15

2

Insurance against Fire

12 17

6

13 7

6

Property Tax

3 10 10

2 2

6

Repairs, Whitewashing, &c

3 14

0

2 0

2

32 15 10 ■

30

5

4

By House Expenditure : —

Coals, Gas, Candles, and Water

17 0 11

18 17

9

Tea and Coffee at Meetings 7

18 18

10

18 14

6

House Duty

6 7

6

6 7

6

Cleaning, Brushes, Sundries

4 17

9

6 2

7

47 5

0 -

50

2

4

By Administrative Charges : —

Wages of Keeper of Rooms

57 4

0

57 4

0

Postages and Carriage of Parcels

20 7

2

26 17

4

Attendance on Sections and Societies

14 11

6

15 14

0

Stationery and Printing Circulars

12 12

6

8 9

3

104 15

2 -

108

4

7

By Publishing : —

Printing Memoirs

50 9

6

74 4

6

Printing Proceedings

57 11

0

63 15

0

Wood Engraving and Lithographing

14 11

0

6 3

3

Editor of Memoirs and Proceedings

50 0

0

50 0

0

172 11

6 ■

194

2

9

By Library : —

Binding Books...

78 10

6

35 2

6

Books and Periodicals

50 4

6

11 2

6

Assistant in Library

12 4

0

11 6

0

Old Memoirs of the Society

1 12

0

Geological Record for 1876

0 10

6

0 11

2

Palseontographical Society for 1879....

1 1

0

1 1

0

Ray Society for 1877, 1878, and 1879

3 3

0

145 13

6 -

60 15

2

By Natural History Fund : —

Investment — £1225 Great Western Railway

Stock '

1489 18

0

Brokerage on ditto

7 9

0

Legal Charges

41 12

0

Works on Natural History

36 9 11

*

Grant to Microscopical and Natural His-

tory Section for Books

100 0

0

1675 8

11

60

0

0

By Balance

8 10

0

1726

4

2

£2186 19 11

£2229 14

4

1879. — April 1. — To Casli in Manchester and Salford Bank

£8 10 0

April 8, 1879, Audited and found correct,

(Signed) JAMES BOTTOMLEY,
R. S. DALE.

128

The following letter, dated April 24th, 1879, from Mr.
Arthur W. Waters, F.G.S., was read : —

On February the 9th, 1876, I wrote you a letter, which
was published in the Proceedings of the Literary and Philo-
sophical Society, giving an account of the Naples Zoological
Station, and as the Mittheilungen aus der Zoologischen
Station zu Neapel shows that it has expanded since then
into a more important establishment, I send a few supple-
mentary particulars gathered from this first volume.

Since the date of my last the Station has received a small
steamer for dredging purposes, partly through the liberality
of the Berlin Academy, which voted 18,000 marks for the
purpose, and the Prussian Government 6,000 marks. Dr.
Dohrn has also made a more satisfactory arrangement with
the Italian Government, who granted him the lease of the
land for thirty years, and have now extended the term to
ninety years.

The accomodation has been increased so that now, tables
for 26 naturalists can be furnished, and the staff is very
materially larger, there being now 25 constantly employed
about the station. The increase has taken place in all
departments, though the most material is in the scientific
staff, which has been doubled. Dr. Berth old has charge
of the botanical section, and Dr. Paul Mayer has the task of
seeing after the zoological collections, and some other
changes and sub divisions have been made, but Dr. H. Eisig
from whom the naturalists who have already visited the
Aquarium have received material assistance, still represents
Dr. Dohrn in the detail control of the entire establishment.

The addition of the steamer has caused changes among
the engineers, and necessitated several more boys about the
place. These boys are much more important than would at
first thought be supposed, for an intelligent lad soon learns
to distinguish the animals which the specialists are investi-
gating, and after a time knows the scientific names of a large
proportion of the animals brought in., and in fact will soon
have a wider superficial grasp than most of the naturalists,
and able to quickly “spot” the animals required. The

eldest boy (Torillo) when I was there had devoted himself
diligently to increasing his knowledge, and was able to give
valuable assistance, and I see he has had more important
duties assigned to him, and Dr. Dohrn speaks of the increas-
ing knowledge of the other boys.

The first volume of Mittheil ungen contains several valu-
able papers. The continuous observations of Mr. Schmidtlein
on the habits of the animals in the Aquarium bring out
much that is interesting, and such observations are much
needed in all aquaria. Dr. Dohrn discusses the zoological
position of the Pycnogonidae. Dr. P. Mayer has in each
part a ps.per on Carcinological studies, and in the second he
follows up Mr. Bullar s investigations on the Isopoda, and
supports most of his conclusions, showing the curious
hermaphroditism of the group, the young being active males,
while as they grow older most of the male organs wholly or
partially disappear, in connection with which the female
organs are then developed. Dr. Falkenberg gives a synopsis
of the fucoids of the bay of Naples.

Most but not all of the papers in these two parts are by
the staff, but the number of papers giving the result of
studies made in the Station by naturalists is now very con-
siderable, and is spread over the periodical literature of all
scientific Europe.

As the institution now lays itself out more and more for
supplying material to naturalists, prepared according to their
instructions, the list with prices which is given at the end
of the second part, will be of service to anyone requiring
such aid.

This is much the largest zoological station, and may be
looked upon as to a great extent the parent of others now
springing up in many directions. Quite recently the Triest
zoological station has also published three parts of a volume,
containing a series of most valuable results attained there.
There is also the station at RoscofF, which supplies the
“Archives de zoologie experimentale” of M. Lacaze-Duthiers
with many important papers. There is a more or less per-
manent station on one of the islands near Denmark, and it

130

is proposed to start one in Sydney, and if the ideas of the
promoter are carried out, this will only he one of a series of
stations confederated together in the southern hemisphere.

The extension of the Naples station has of course materi-
ally added to the expense, and as it is now so generally felt
that biological science is very largely indebted to Dr. Dohrn’s
indefatigable perseverance, it is to be hoped that he will
receive all the support he expects.

MICROSCOPICAL AND NATURAL HISTORY SECTION.

Annual Meeting, April 7th, 1879.

Charles Bailey, Esq., in the Chair.

The Treasurer s Account and Report of the Council were
read and passed.

The Election of Officers for the ensuing year then took
place as follows :

^prcsfrcnt.

C. BAILEY, P.L.S,

Utcc=qj3 residents.

THOMAS ALCOCK, M,D.

H. A. HURST.

A. BROTHERS, F.R.A.S.

treasurer.

T. II. BIRLEY.

Secretary.

J. COSMO MELVILL, M.A., F.L.S.

(Eourtctl.

W. C. WILLIAMSON, F.R.S.

JOSEPH BAXENDELL, F.R.A.S.

JOSEPH SIDEBOTHAM, F.R.A.S.

R. ELLIS CUNLIFFE.

JOHN BOYD.

JOHN BARROW.

E. W. BINNEY, F.R.S. , F.G.S.

W. BOYD DAWKINS, F.R.S., F.G.S.

List of Members and Associates of the Section : — -

J^tcmtms.

Alcock, Thomas, M.D.

Bailey, Charles, F.L.S.
Barratt, Walter Edward.
Barrow, John.

Baxendell, Joseph, F.E.A.S.
Bickham, Spencer H., Jun.
Binney, E. W., F.B.S., F.G.S.
Birley, Thomas Hornby.

Boyd, John.

Brockbank, W., F.G.S.

Brogden, Henry.

Brothers, Alfred, F.E.A.S.
Cottam, Samuel.

Coward, Edward.

Coward, Thomas.

CuNLIFFE, BoBERT ELLIS.

Hale, John, F.C.S.

Dancer, Jno. Benjamin, F.E.A.S.
Dent, Hastings Charles.
Derbyshire, E. D., B.A.

Dawkins, W. Boyd, F.E.S., F.G.S.
Deane, W. K.

Higgin, James, F.C.S.

Hurst, Henry Alexander.
Latham, Arthur George.
Martin, Sidney Trice.

Melvill, J. Cosmo, M.A., F.L.S.
Mooke^ Samuel.

Morgan, J. E., M.D.

Nevill, Thomas Henry.

Nix, E. W„ M.A.

Egberts, William, M.D.
Sidebotham, Joseph, F.E.A.S.,
F.L.S.

Smith, Eobert Angus, Pli.D.,
F.E.S., F.C.S,

Williamson, Wm. Crawford,
F.E.S., Prof. Nat. Hist.,
Owens College.

Wright, William Cort.

Associates.

Becker, Wilfrid, B.A.

Hartog, Marcus M., B.Sc., F.L.S.
Kimmins, C. W.

Labrey, B. B.

Linton, James.

Peace, Thos. S.

Perciyal, James.

Plant, John, F.G.S.
Eogers, Thomas.

Stirrup, Mark, F.G.S.
Tatham, John F. W., M.D.
Young, Sydney.

132

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133

Mr. Hurst gave a list of the Leguminosse of the Riviera
collected by Joseph Sidebotham, Esq., in the winter of

1877-78.

Argyrolobium Linnseanum, Walp.

Genista Germanica. L.

„ sericea. Wnlff 1

Spartium junceum. L.

Cytisus albus. Link, a J.S.

„ Ursulas. L.

Ononis minutissima. L.

Anthyllis tetraphylla. L.

„ vulneraria. y. rubriflora. L.

Medicago littoralis. Rhde.

„ minima. L.

,, orbicularis. All. Very fine.

„ maculata. Will.

Melilotus officinalis. Desr.

Trifolium stellatum. L.

„ montanum. L.

„ patens. Scbreb.

„ scabrum. L.

Dorycnium suffruticosum. Mill.

„ hirsutum. X). C.

Lotus ornithopodioides. L.

,, edulis. L.

Psoralea bituminosa. L. ^

Astragalus monspessulanus. L.

do. Imperfect.

Scorpiurus subvillosa. L.

Coronilla Emerus. L.

„ valentina. L.

„ minima. L.

,, varia. L.

Arthrolobium scorpioides. L,

134

Ornithopus compressus. L.

Hippocrepis unisiliquosa. L.

Onobrychis. Resembles 0. equidentata in foliage.

Yicia bybrida. L.

Ervum nigrescens. L.

Lathy ms sativus. L.

„ setifolius. L.

„ 1 imperfect.

Orobus tuberosus. L.

Mr. Hurst likewise read a communication from Pv
Planta on the Grasses of Egypt, enumerating as follows
those found : — ■

Graminees cVEgypte.

Andropogonece.

Imperata cilindrica (Hoat) M. Tell, Sembaleven. Piraymides.
Saccharnm iEgyptiacum (Wild). Sicile. Rosette.

Sorghum halepense (Pers). M. Ramie.

Andropogon annulatum(Del). (deM. Letourneaux). M. Damenhour.

Panicece.

Panicum turgidum (Del). M. Mokatham.

Panicum crus galli (L). G. Rosette.

Panicum numidianum (Lam.) (muticum Forsk.) M. Rosette.
Panicum cruciforme Sibth. M. Rosetta.

Setaria verticillata (Pers). M. Ramie.

Pennisetum dichotomum (Dei). M. Mokattam.

Phalaridece.

Phalaris paradoxa (L). M, Piramides Sembaleven.

Phalaris aquatica (L). M. Gabari.

Phleicce.

Crypsis Schoenoides (Lam). M. Ghizah, Mandara.

A grostideae.

Polypogon monspeliense (Deof). M. Gabari.

Agrostis pungens (Zehreb). M. Ramie.

(Sporobolus pungens) (Kunth).

135

Agrostis verticillata (Vill). M. Ramie.

Agrostis spicata (Del). M. Ramie.

Stipcicece.

Stipa tortilis (Desf). M. Ramie.

Aristida plumosa (L). M. Mokattam.

Milium vernale (Rehb). M. Alexandria.

Arundinacece.

Arundo isiaca. (Del). M. Rosette.

Phragmites communis (L). G. Rosette.

Amophila arenaria (LR). (de M. Letourneaux). G. Mandara.

Chloridece

Cynodon Dactylon (Pers). G. Ramie.

Dactyloctenium iEgyptiacum. Sicile. Ramie.

Agrostidece.

Aira minuta. M. Ramie.

Avena neglecta (Savi). (Trisetum neglectum, RS) M. Ramie.
Avena hirsuta (Wood). Sicile. Ramie.

(Avena sterilis L. var. hirsuta)

Avena arundinacea (Del), de M. Letourneaux. M. Mandara.

Festucacece.

Kocleria phleoides (Pers). M. Alexandria.

(Lophocloa phleoides (Will).

Schismus calycinus (Wood). Schismus marginatus (Beau).

Festuca calycine (L). M. Ramie.

Poa annua (L). G. Alexandria.

Poa cynosuroides (Vahl). M. Piramides.

Eragrostis megastachya (LK). M. Ghizeh.

(Briza eragrostis) (L).

Chrysurus aureus (Pers).) (Lamarkia aurea) (Melh). M. Ramie.
Dactylis repens (Desf). (Dactylis littoralis) (Wilde).

Festuca fusca (Del). M. Sembeleven.

Festuca divaricata (Desf). M. Ramie.

Bromus confertus (M.B) M. Mex.

Bromus rubens (Del). M. Ramie.

Bromus madriteusis (L). Ramie.

Bromus polystachyos (DC). M. Ramie.

/3

136

Hordeacece.

Trachynia distachyos (LK). (Bromus distachyos (L). Ramie.
Lolium figidum (Goud) M. Ramie.

Lolium siculum (Wood). Sicile. Ramie.

Lolium arvense (With). G. Ramie.

Triticum bicorue (Forsk). AE. Ramie.

Catapodium loliseceum (LR). M. Ramie.

(Triticum loliseceum (Smith).

Aegilops triaristata (Wild). M. Ramie, Mex.

Hordeum murinum (L). G. Sembeleven.

Hordeum maritimum (Vahl). G. Ramie.

Rottboelacece.

Lepturus incurvatus (Tr.) (Rottbolha incurvatee (L). G. Ramie.
Lepturus filiformis (Tr.) Rottbollia filiformiee (Rottb). G. Ramie.

Cyperacce.

Cyperus glaber (L). (de M’Letoumeux) M.

Cyperus articulatus (L). (de M’Letourneux). M.

Cyperus conglomeratus (Rattb). (de M’Letourneux)

Cyperus mucronatus (Rottb). M. Rosette^

Cyperus panonicus (Rottb). (?) Alexandria.

Cyperus longus (L). M. Alexandria.

Cyperus fuscus (L). M. Alexandria.

Cyperus Dives (Del) M. Rosette.

Scirpus macrostachyus (Wild). M. Rosette.

Scirpus Michelianus (L). G. Alexandria.

Scirpus littoralis (Schrad). fimbrisetus (Del). M. Alexandria.
Scirpus maritimus (L). corymbosus (Forsk). G. Alexandria.
Schoenus mucronatus (L). Scirpus Kalis (Forsk) M. Ramie.

N. B. — G signifie que la plante se trouve dans differentes parties
et zones de l’Europe.

M. — Fiore dite de la Mediterranee. Quand I’M est sum d’un
point, la plante appartient a cotte categorie de la flore qui a sa
limite Nord a Trieste a Faenza, en Ligurie, en Provence.

A E. — Plantes trouvees en Egypte seulement ou dans la zone
^Egypto-Arabique, et Indienne.

137

PHYSICAL AND MATHEMATICAL SECTION.

April 22nd, 1879.

E. W. Binney, F.R.S., F.G.S., President of the Section, in

the Chair.

“ Colorimetric Experiments, Part II.,” by James Bottom-
ley, B.A., D.Sc., F.C.S.

In a short note which I read before this Society (Vol. XV.,
p. 63) I proposed to measure quantities of colouring matter
in solution, using the formula qt=qt' in the calculation,
^ and g denoting quantities of colouring matter, and t} t'
lengths of columns of coloured fluid \ the colouring matters
being dissolved in equal volumes of water. Last session I
gave the results of some experiments which I had obtained
two years previously. Lately I have made some further
experiments, which I give in this paper, along with some
additional remarks on colorimetry. In my last paper I took
0001 grams as the unit of measurement. For comparison
I have retained it in this, although the quantities used can
can no longer be considered as traces. The colouring mat-
tei used was ammonio-sulphate of copper. A solution was
made by dissolving 10 grams of crystallized sulphate of cop-
per in a mixture of 200 cubic c. of water and 50 cubic c. of
ammonia. Mixtures of various degrees of intensity were
made by taking portions of this solution and mixing with
water so as to make up 500 cubic c. As in my last paper,
A denotes the amount of the colouring salt present, B the
length of the column of fluid, and C the amount of the
colouring salt thence derived by calculation.

Standard solution 4000 in 500 cub. g. of water (depth of
disc 8’3)

ABC
6000 4*3 7721

138

a result considerably remote from tlie correct value. Also
when the disc was placed inside the solution at the depth
given by theory, it seemed too dark. Next, a comparison
was made by looking through the cylinders at external
white surfaces. Standard solution 4000 in 500 cub. c. of
water, length of column 8'4.

ABC
6000 5-1 6588

Thus the result is considerably different from the real value.
Also both experiments concur in giving too high a value.
The theoretical depths moreover were tried with external
surfaces, and seemed slightly too great. My next experi-
ments were made with solutions containing 2400 and 1600
of sulphate of copper. The discs being inside the results
were as follows : standard solution 1600 in 500 cub. c., depth
of disc 8*3.

ABC
2400 5-6 2371

The number under B was the result of seven trials. The
value under C is a fair approximation to the real value. I
also tried external surfaces with these solutions. Standard
solution 1600 in 500 cub. c., length of column 8*4.

ABC
2400 6*2 2161

somewhat further from the correct value than we might
expect. I also tried the theoretical length of column ; with
external discs it appeared a little too light. The results
obtained with the last standard solution are inconsistent
with the results obtained with the first. In the latter case
the results are too low, while previously they were too
high. Errors of observation arising from imperfect percep-
tion of colour, from imperfection of instruments and
unfavourable conditions of light (for many of the experi-
ments were made during the winter months, sometimes on
gloomy unfavourable days) would no doubt contribute to

139

this result, yet allowing for all these, there seemed to be
some other cause. In my last paper I mentioned that an
ammonaical solution of copper, when largely diluted, became
turbid, and that to carry out the experiment an additional
quantity of ammonia was necessary. This small quantity
was added at hazard, as I did not think it would have any
influence on the result. It seemed to me afterwards to be
a point worth examining in connection with the above
experiments. Two solutions were made, each containing
5 cub. c. of the previously mentioned copper solution with
245 cub. c. of water. The solutions were placed in similar
cylinders — to one of the cylinders more ammonia was
added : it appeared perceptibly darker than the other.
Hence it appears that the excess of ammonia has some
influence on the result. I presume that ammonio-sulphate
of copper has a tendency to be decomposed by water, and
that some change is effected even before it becomes
obviously marked by the formation of a turbidity; moreover
it seems likely that the excess of ammonia has the power
to counteract this property of water, and to restore the
original compound. Two solutions were made, the bulk of
each being 545 cub. c., one containing 4000 of copper
sulphate, along with an additional 20 cub. c. of ammonia,
the other containing 6000 of copper sulphate with 30 cub. c.
of additional ammonia. The comparisons were made in new
cylinders graduated to millimetres. An experiment with
white surfaces, external, gave the following results :
Standard solution 4000 in 545 cub. c. of water, length of
column 23 cm.

ABC
6000 15-5 5955

thus the result is very near the real quantity. I also took
shorter lengths of the standard solution, namely 18 cm., 13
cm., and 8 cm., the corresponding lengths of the other
solution were 12-4 cm., 8*5 cm., and 5*3 cm. Reduced to 23 cm.

140

of the standard, the lengths would be 15 '8, 15, 15*2, numbers
not far removed from 15 ‘5, which was got by observation.

I repeated the experiment with fresh solutions, the bulk of
the liquid being 500 cc. Standard solution 4000 in 500 cub,
a, length of column 2T2.

ABC
6000 14-1 6000

The number under B is the theoretical quantity, and was

the mean result of four trials. Also with shorter columns

of the standard liquid, namely 15*2 cm., 10'2 cm., 5*2 cm.,

the corresponding lengths of the stronger liquid gave similar

tints. At the same time lengths differing a little from the

theoretical would also satisfy. With these solutions I also

tried an experiment with discs inside. Standard solution

same as last :

ABC
6000 12*3 6894

The number under B was the mean of 15 trials, thus the
result with discs inside was not so good as with discs out-
side. Also 14*1 cm. the theoretical depth when tried
seemed slightly too dark with discs inside. I repeated the
experiment with a solution containing 2400, using one
containing 1600 as a standard. In preparing these solu-
tions to the stronger I added 12 additional cub. c. of
ammonia, and to the weaker 8. With external white sur-
faces the results were as follows : — standard solution 1600
in 500 cub. c. of water, length of column 21*2 cm.

ABC
2400 13-8 2458

The number under B was the result of fifteen trials. Thus
we get a good approximation to the real quantity. With
discs inside the results were as follows. Standard solution
same as last :

ABC
2400 12 2824

The number under B was the mean of twelve trials. The

141

value got with discs inside is not so good as with discs
outside. Also the theoretical depth 14*1 cm. when tried
seemed to be slightly too great. From the foregoing experi-
ments it would appear that with considerable additions of
ammonia the results with discs outside were much improved.
Why the results were not equally good with discs inside
may, I think, be accounted for, and will be considered
further on. I also compared the solution containing 4000
with the one containing 1600. Standard solution 1600 in
500 cub. c., length of column 21 2.

ABC
4000 8 4240

The number under B was the mean of eight trials. The
theoretical length was 8 ’5 ; with the standard solution on
the left hand this length seemed to give a similar tint, but
with standard solution on right it seemed a little darker ;
and now I remarked for the first time, or, if I had previously
remarked it, had not thought it worthy of notice, that even
an apparently so trivial circumstance as altering the posi-
tions of the cylinders from right to left had a perceptible
influence in the determination of colour. I afterwards
made some experiments to test this. Next I compared
solutions containing 1600 and 6000. Standard solution
1600 in 500 cub. c., length of column 21*2.

ABC
6000 5T 6682

The number under B was the mean of eight trials. The
result is not so satisfactory as the others. I also tried these
solutions with white surfaces inside. Standard solution
same as last :

A B C

6000 3-9 8697

A widely remote result, and much further from the rea]
value than with discs outside, also a disc placed in the solu-
tion at the depth assigned by calculation seemed too dark.
It seemed possible to me that a more satisfactory result

142

than this experiment had yielded might be obtained. The
excesses of ammonia used in the experiments were nearly
proportional to the quantities of sulphate of copper in solu-
tion ; but if we regard water as an agent whose tendency is
to diminish the intensity of the colour, and ammonia as an
agent whose tendency is to restore the colour, it would
seem reasonable that the ammonia should be proportional
to the water. The difference of the excesses of ammonia
in the last two solutions was large, being 22 cub. c. I pre-
pared fresh solutions, one containing 4 cubic c. of the copper
solution with 30 cub. c. of additional ammonia and suffi-
cient water to make 500 cub. c. The other solution con-
tained 15 cub. c. of the copper solution with 30 cub. c. of
additional ammonia, and sufficient water to make 500 cub.
c. The quantities of the copper solution taken should cor-
respond to 1600 and 6000 of copper sulphate ; to guard
against imperfect measurements from the burette; I also
weighed the solutions. The 4 cubic centimetres weighed
3‘9854 grams, and the 15 cubic centimetres weighed 14-99
grams. The ratio of the volumes is 375, and the ratio of
the weights is 3-761, so that the error of measurement
would be but small.

With discs outside the results of experiments were as
follows. Standard solution 1600 in 500 cub. c. of water,
length of column 21*2.

A B C

6000 6 5653

The number under B was the result of eight trials ; also the
standard solution was on the left hand. With the standard
solution on the right the results were

ABC
6000 5-4 6283

The number under B was the mean result of eight trials.
In one case the value got by experiment is too high, and
in the other too low. The theoretical length is 5-65, and

1 43

5*4 is not very far from it. When I actually tried a column
of the theoretical length it seemed to give the required tint
when the standard solution was on the left; when the
standard solution was on the right it seemed a little darker.
The mean of the two values previously obtained is 5968,
which is near to the real value. From the above experi-
ments it seems that when excesses of ammonia are added,
very fair approximations may be obtained by colorimetry
to the quantity of copper sulphate in solution, the white
surfaces being external. Also that with white surfaces
internal the results are more remote. In my last paper I
stated that when there was much difference between the
standard solution and the one to be compared with it, the
discrepancies when internal discs were used were consi-
derable. Then I was using very small quantities of colour-
ing matter. From these experiments where the colours
were intense and the quantities of colouring matter used
considerable, a similar conclusion follows. The reason for
this is not far to seek, and it also suggests a correction that
must be applied to the formula when the white surfaces are
inside. A white disc inside a column of coloured liquid
looks darker in colour than a white disc outside, placed a
few inches below a column of the same length. This may
be tried by looking through different columns, or through
the same column, and having inside a white disc of smaller
diameter than the cylinder ; the inside disc will then appear
surrounded by a rim of lighter colour. When the disc is
internal, it is evident that the light which illuminates it has
previously passed through the solution, so that we are look-
ing not at a white disc, but at a coloured disc through a
coloured solution. Some allowance must be made in the
calculation for this coloration of the disc. The formula
qt = qt' is applicable to the case in which the surfaces are
outside ; to adapt this formula to the case when the discs
are inside, suppose x to be the length of the column of fluid

144

which would cause the difference in colour between an
external and an internal surface, then the formula would he
q(t + x) = q(t' + x). To find the value of x experimentally, I
took a solution containing 2400 and sunk a small disc in it
until the inside and outside colour seemed the same ; for
the outside the length of column was 22f5 ; for the inside
17 7, this being the mean of eight trials. The difference is
4-8. With a solution containing 1600, a white surface out-
side, with length of column 21 % seemed to give the same
colour as white surface inside with length of column 16*2.
The difference is 5. 1 also tried to get the value by the

following combination. A solution was taken, containing
2400 with disc inside, and compared with a solution contain-
ing 1600 with a disc outside ; length of column in latter case
was 21*2, in the former case a column 17*5 seemed to give
a similar colour. From the formula q(t+x) = q't' the result-
ing value of x would be 5 2. I also tried the following com-
bination. Solution containing 2400 and disc outside was
compared with solution containing 1600 with disc inside —
the mean of eight trials gave length of column 17 in the
latter case, equivalent to 21 2 in the former; from the for-
mula 1600 (17 + $)=2400 X 21*2, the resulting value of x
is 4’3 — finally we get for the approximate value of x, taking
the mean of the four determinations, x=4r8 The experi-
mental determination is not easy, but the value obtained
gives better results when we use it in the formula ; for in-
stance, on a former occasion with discs inside, when a
solution containing 1600 and length of column 21 ‘2 was
used as a standard, and there was compared with it a solu-
tion containing 2400, the length of column was 12; from
the uncorrected formula the result is 2824 ; from the for-
mula

^(12 + 4-8) = 1600(21-2 + 4*8)

the resulting value of q is 2476, which is not far from the
proper value. When the fluids compared differ much in

145

strength, the value of the correction will probably vary. It
will be better not to have the difference large, whether the
discs be external or internal, for when the differences are
large any errors in the determination of the lengths of the
columns have a greater effect on the calculated result. I
also tried to make a rough estimate of the length of the
cylinder, which might be covered without any perceptible
darkening of the disc. I found that a black cloth cover
investing the cylinder might be drawn down until it was
about 3 5 or 32 cm. from the disc; this would vary with
the dimensions of the window and the relations of the cylin-
der to it. Also the length given is less than the value of
x previously deduced ; but it ought to be so, for the light
from a vertical window to illuminate a horizontal disc must
pass obliquely through the solution. It would a]so follow
that parts of the disc more remote from the window are
darker than parts nearer, hence if the cylinders are of
moderate radius, either the discs should be small and should
be kept with their centres moving along the axes of the
cylinders, or in the case of larger discs the determination of
colour should be made by a comparison of similar parts of
the discs. In the estimation of colour it is also not a matter
of indifference, when we are given any tint as a limit, how
we approach that limit. Suppose we have two cylinders, a
and j3, full of coloured liquid, that in a being the darker.
Now pour out from a until the colour seems the same as in
(3 ; before reaching the theoretical division sight will fail to
discern any difference of colour. Now if we proceed
cautiously, as we approach the limit there will be a natural
hesitation and tendency to stop, and it seems likely that in
most cases in obedience to that feeling we shall stop with a
column a little too long. Now suppose we start with the
cylinder a empty, and pour fluid into it; as we again
approach the limit cautiously we shall again have a tendency
to stop, and inasmuch as before reaching the limit we pass

146

through tints which we cannot distinguish from it, we are
likely to take a column of fluid too short. In my own
case I have noticed this on several occasions ; for example,
in trying to estimates particular colour the mean of seven
trials made by pouring out from the cylinder gave 141 as
the length of the column, the mean of seven trials made by
pouring into the cylinder gave 13*7 as the length, and with
discs inside the mean of six trials made by moving the disc
from below upwards gave 12 5 as the length of column,
while moving from above downwards the mean of six ex-
periments gave 11*7. In trying to estimate a colour it
seems to me that it would be well to approach the limit by
both ways, and then take the mean of the results.

In a previous part of this paper I stated that altering
the position of the cylinders made a little difference in my
perception of colour. I made some experiments to try this.
I took a solution containing 2400 and poured from the
cylinder on the right hand into the cylinder on the left hand-
the columns ought to be equal. The mean of nine trials
o-ave length of column on right hand 112 ; length of column
on left hand 10-61. In these experiments, the judgment was
made using both eyes. I next tried using one eye only —
with the right eye the results were, length of column on
right hand 1 0*86, length of column on left hand 1109; these
numbers were the mean of nine trials. With the left eye
alone, the results were, right hand cylinder 10-78, left hand
1101, being the mean of nine trials; thus using one eye
only, the results are nearly the same in both cases ; they
also tend to make the right hand a little less, thus reversing
the case of two eyes. These experiments were made in a
room with a small window facing the south. I afterwards
repeated the experiments, using two eyes, in another room
having a window of larger dimensions and facing the north.
A solution was used containing 1600, the mean of nine
trials gave right hand cylinder 11*16, left hand 1055, nearly

147

the same results as I got before. Why I should have
this tendency to make one column a little larger than the
other I do not know; possibly it may be some peculiarity of
vision confined to myself. In the course of my experiments
I have also noticed the following curious phenomenon, and
this repeatedly, when working with solutions coloured with
bichromate of potash, and with ammonio-sulphate of copper ;
look steadily with one eye, say the right, through the solu-
tion at a white surface, after the lapse of abour a minute
suddenly turn the head so as to bring the left eye close over
the cylinder, then the colour will seem more intense than it
did with the right ; having looked with the left eye for about
a minute, bring again the right eye suddenly close over the
cylinder, and the colour will seem more intense than it did
with the left, and so on alternately. It would seem as if
the first impressions of colour on the eye were the stronger,
and as if there were a gradual and imperceptible decrease in
intensity — perhaps alterations in the aperture of the pupil
may contribute to this. Another matter for consideration
in colorimetry is the nature of the incident light. On some
occasions we have the light from a blue sky; on other oc-
casions the sky is invested with clouds of various depths of
grey, or sometimes tinged by the sun with a variety of tints,
from yellow to red ; while the light of the sun itself is fre-
quently yellow or orange. All these variations of light are
likely to have some influence in our judgment of colour,
especially when the tints to be compared are light. Of the
disturbing influence of colour in the incident light, anyone
may convince himself by comparing yellows on a morning
when the sky is enveloped in a yellow fog. In some experi-
ments which I made with bichromate of potash during such
fogs, I found it much more difficult to decide at what depth
equality of colour was effected ; the disc in the stronger so-
lution could be moved through a very considerable range
without any change of colour being perceived. A similar

148

result happened when I hung up yellow screens and tried
to make determinations of colour behind them ; also when
looking at light yellow external surfaces, differences in the
lengths of the columns failed to give any difference in tint,
although when looking at white external surfaces they did
so. But in quantitative determinations of matter by colo-
rimetry, the excellence of the results require sensible varia-
tions in colour when we alter slightly the length of the
column ; hence when the incident light is tinged with the
colour we wish to determine the advantage of the method is
diminished. Such a consequence may also be deduced from
the formula which I obtained in my last paper. For sup-
pose white light to consist of yellow, blue, aud red (as far
as the reasoning is concerned we might have considered it
also composed of green, red, and violet, as some physicists
do). Let I denote the incident white light, and B, Y, It the
intensities of blue, yellow, and red necessary to produce
white light, so that we may write :

I = B + Y + E.

Let there be two solutions containing q and q' of yellow
colouring matter, and t and t' the corresponding lengths of
columns; then the intensity of the light transmitted through
one cylinder will be

(1 - mqt) Y + (1 - mxqt)R + (1 - mxqt) B,
m denoting the amount of yellow light absorbed by a unit
layer, and mx the amounts of red and blue absorbed by a
unit layer. Also the light transmitted by the other cylinder
will be

(1 - mqt1) Y + (1 - miqt'JR + (1 - mqt') B.

Since both cylinders are of the same colour these expres-
sions will be equal, m will be less than mx because the
transmitted light is yellow ; let m = mx - fi. Then we shall
have

1(1 - mxqt) + fiqtY - 1(1 - mxqi) + fiqt! Y) (A)

The expression on the right hand denoting the light trans-
mitted through one cylinder, and the expression on the left

149

hand denoting the light transmitted through the other
cylinder. Each expression consists of two terms, the terms
of the form 1(1 — m-yqt) denotes the white light transmitted,
the term of the form pqtY denotes the excess of yellow ;
this term we may call the effective yellow, for it is the only
portion which produces the sensation of colour. Now sup-
pose the light before passing through the cylinders to pass
through a yellow screen, suppose the composition of the
incident light after transmission through the screen to be

pY + piB + pih,

p being greater than p1} say p = p1+r, so that the composi-
tion of the light may be written

Pil + rY,

rY being the effective yellow after passing through screen.
After using the screen the left hand expression of A would
become

I/o1(l - mxqt) + Yr - Yrmxqt + pxqtYfi.

Since qt = q't', if we substitute eft' for qt in the last expres-
sion, we shall get the light transmitted by the other cylinder
after using a screen; hence if the columns be adjusted so as
to produce equality of colour with white light, they will
still be in adjustment if the light should become tinged
with yellow.

Let yx and y 2 denote the effective yellows in one of the

cylinders with white incident light and with yellow light ;

then we shall have

y1 = fiqYt

y2 = Yr - Yrniiqt + Y pXfiqt

Now suppose the length of the column of coloured liquid to
be altered a little so as to become £ + §£, let Syx and Sy2 de-
note the alterations in the effective yellow in each case, then
hy% = (Ypi \xq - Yrmxq)U
tyi = Y pqU

Hence

<^2 ~ tyi= “ { Yrvthq + /JLqY(l - pi)}&5

Therefore Sy is less than Sy1} that is to say, we shall not see

150

so much difference of colour for a given alteration of depth
when the light is tinged with yellow as when it is white ;
therefore the sensibility of the method is diminished. This
may he put in another way. When the incident light is
tinged yellow, the expression for the effective yellow after
transmission through the cylinder is

Y r - Yqt(rm1 - px/i)

Suppose the term in brackets to vanish, then the expression
for the effective yellow becomes Y r, which is independent
of the quantity of colouring matter and of the length of the
column.

I