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CONTENTS.

Some Notes ox the Biology of the Larger
British Fungi.

By Somerville Hastings, M.S.. F.R.C.S. 129

Science in the Daily Press 137

Chapters in Spectrum Analysis. I {continued*.

By W. Marshall Watts. D.Sc. 138

Khaki Dye 141

German Science.

By Professor J. Arthur Thomson, M. A., LL.D. 142

Solar Disturbances during March. 1915.

By Frank C. Dennett. 144

The Cause of Albinism and Dominant Whiteness.

By H. Onslow. 145
Notes. —

Astronomy.

By A. C. D. Crommelin, B.A.. D.Sc. F.R.A.S. 146

Botany. By Professor F. Cavers, D.Sc, F.L.S. 149

Notes [continued): —
Chemistry.

By C. Ainsworth Mitchell. B.A.. F.I.C. 150

Geography By A. Scott. M. A.. B.Sc. 150

Geology. By G. W. Tyrrell, A.R.C.Sc. F.G.S. 151

Meteorology. By William Marriott. F.R. Met. Soc. 152

Microscopy By F.R.M.S. 152

Photography. ... ... ... By Edgar Senior. 154

Physics. By J. H. Vincent. M.A.. D.Sc. A.R.C.Sc 154

Radio-Activity. By Alexander Fleck. B.Sc. 155

Zoology.

By Professor J. Arthur Thomson. M. A., LL.D. 155

The Face of the Sky for June.

By A. C. D. Crommelin. B.A.. D.Sc. F.R.A.S. 157

Reviews 15&

Notices 160

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Index of Spectra

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SOME NOTES ON THE BIOLOGY OF THE LARGER

BRITISH FUNGI.

By SOMERVILLE HASTINGS, M.S., F.R.C.S.

In the following pages an attempt will be made to
describe simply some of the more interesting
points regarding the life - history of the larger
British Fungi. As is the case with most living
things, a large proportion of the energy of nearly
all the members of the mushroom tribe is given up
to the perpetuation of their kind. Therefore, in
the description of the life-history of mushrooms and
toadstools, the structure of the organs bearing the
spores and the dispersal of the spores themselves
take a very large share ; indeed, the only part
of the fungus plant known to most people, namely,
the mushroom or toadstool, has solely to do with
the formation and dispersal of the spores. In a
previous article on this subject (see " Knowledge,"
Volume XXXVII, pages 98, 124, 168) the question
of spore-formation and dispersal has already been
gone into, and it will not be further mentioned
in the present paper.

In the common mushroom the plant itself is
formed of fine threads, called mycelium (see
Figures 100 and 102), which live in the soil and
obtain their nourishment from the organic
matter contained therein. The mushroom plant
is entirely free from chlorophyll, and is therefore
incapable of obtaining any of its organic
constituents from the air. It feeds exclusively

on formed organic matter. When the mushroom
plant has obtained a sufficient store of nourishment
spore-production begins, and what we call mush-
rooms then appear. These organs are wonderfully
adapted for the production of myriads of tiny spores,
which are carried broadcast by the wind, and
when they fall on suitable material they rapidly
germinate and produce fresh mycelium. Fungus
plants have again and again been grown on various
sterilised materials from their spores, and have
been induced to go through their complete life-
cycles. Fischer was able to grow the Beechtuft
(Annillaria mucida) (see Figures 118 and 122)
from its spores on sterilised bread kept moist, and
to obtain from it typical toadstools, which ripened
a second crop of spores in fifty-eight days from the
time the first spores germinated. When the spore
germinates it puts out a thread-like process, which
gradually elongates, and, later on, begins to branch.
The process tends to grow in the direction of any
nutritive substance on which the fungus feeds.
The attraction is simply chemiotaxis, and does not
imply any vital function. The Japanese, Miyoshi,
sowed fungus spores on a plate of mica, which was
pierced by numerous tiny holes, and rested on a mass
of jelly containing sugar and other nutritive sub-
stances. He found that the fine threads growing

129

130

KNOWLEDGE.

May, 1915.

from the spores travelled along the surface of the
mica until they came to one of the tiny holes,
down which they passed into the nutritive substance
below it. The spores of most fungi germinate
best directly they are shed, as they are in most
cases frail bodies, easily destroyed by adverse
conditions. Fischer showed that the spores of the
Beechtuft germinated slowly and with difficulty
after a month, and after six weeks failed to ger-
minate at all. Unlike most plants, the fungus plant,
or mycelium, is capable of withstanding adverse
conditions much better than are its spores. The
mycelium is really the resting stage.

Toadstools often come up in nearly the same spot
year after year. In a garden near the centre of
London the Horse Mushroom (Psalliota arvensis)
(see Figure 103) has appeared every year for the
last fourteen years to my certain knowledge.
There is an oak tree in Epping Forest on which
the Beefsteak Fungus (Fistulina hepaiica) has
been seen by me almost every year for
the last ten years. Fries mentions that he
had found a somewhat rare toadstool growing from
a beech tree in 1815, and that he again found the
same fungus appearing from the same crack in
the same tree in 1833, but had seen nothing of it in
the intervening years. The vulnerability of the
spores is so great that some fungi have given up
the production of spores completely, and are
reproduced entirely by the separation of pieces of
their mycelium. A good example of this in the
case of ryegrass will be described later. Smut
is a disease which affects many of the cereal plants.
Its minute spores are sown with the seeds, and
directly the seeds germinate the fungus infects the
tiny plants. By washing the oats with a disinfectant
before they are sown the fungus is killed and smut
is prevented. But in the case of barley the treat-
ment is found to be of no value, because the smut
fungus enters the ovary of the barley while it is in
the flower stage, and thus passes into the seed.
In this condition it remains dormant until the seed
is sown, when it again awakens into activity.
It is probable that the mycelium of most fungi
can go on existing for man}' years in the soil without
producing fruit bodies or toadstools. Thus we find
that some years mushrooms are very plentiful and in
others very scarce. After a warm, wet summer,
fields and meadows abound with toadstools which
are hardly to be seen at all under more normal
circumstances. It is probable in these cases that
the mycelium has existed for many years in the
soil, but that only after the warm, moist weather
has it obtained sufficient vitality to determine on
the production of spores by means of toadstools.
There is also a certain amount of evidence to show
that some kinds of toadstools are found in abund-
ance in some localities every third year. It is clear,
then, that the mycelium, and not the spore, is the
true resting stage in the case of many fungi.

In some forms of fungus the mycelium forms

itself into a firm, dense mass before passing into the
resting stage : these masses are called " sclerotia."
Hard black bodies are not infrequently seen in the
interior of the dead stems of the potato, cucumber,
and man}' other plants. These remain dormant
for a time, and later on the fructification of the
fungus, shaped like a cup in many cases and con-
nected to the sclerotium by fine threads, appears.
The pretty little toadstool shown in Figure 99 is
usually found growing on the dead " fruit " of another
of its kind. From the mycelium small sclerotia are
produced, and from these the tiny toadstools
spring up. Ergot is another example of a sclero-
tium. Large elongated bodies are seen, which form
the resting stage of the fungus. They fall to the
ground in autumn, and remain there dormant all
the winter. From these black bodies short stalks
with purple heads arise in spring, and from these
the spores are given off. In some fungi the resting
mycelium takes the form, not of sclerotia, but of
strands and threads : these are spoken of as
" rhizomorphs." Dark, hair-like threads are often
found among dead leaves : they are rhizomorphs
of a species of Marasmiiis. Underneath the bark
of many a dying tree dark interlacing cords may
be observed which are the rhizomorphs of the Stump-
tuft (Armillaria mcllca) (see Figures 101 and 1 04),
one of the most destructive of parasitic fungi,
and the cause of one of the most serious forms of
timber disease. The fruits of the Stumptuft are
generally found near the bases of trees. A
large mass of them appears in Figure 101. The
fungus reaches the trees in many cases through
a wound, and the mycelium from the germinating
spore spreads in the cambium, that is, the growing
tissue between the bark and the wood, and forms
its rhizomorphs in this region. As it extends inward
the wood is destroyed and the tree is slowly killed,
and from the root of the infected tree rhizomorphs
extend through the soil to infect other trees.
From these rhizomorphs the fruit or toadstool
may be formed, so that Stumptufts may be found
some little distance from the tree on which their
mycelium is growing (see Figure 101). It is an
interesting fact that rhizomorphs which carry in-
fection from tree to tree are hardly ever found more
than six or eight inches from the surface of the soil.
A trench at least a foot deep round an infected tree
will prevent the spread of the disease by the means
of rhizomorphs to other trees around.

That many toadstools tend to come up in rings
has been noticed for a very long time, and many
fantastic suggestions have been invented to explain
the fact, several examples of which may be seen in
Figures 105, 106, 108, and 110. The best known
of these is perhaps the Fairy-ring Toadstool
{Marasmius oreades), but gigantic rings of the Giant
Puffball (Lycoperdon gigantciini) arc also often seen
on limestone downs, and it is curious that in most
cases when no toadstools are to be found the rings
are still recognisable through the darker colour

May. lois.

KNOWLEDGE.

131

Figure 99. Collybia tuberosa growing on a dead
toadstool.

FIGURE 102. The mycelium of a fungus which has spread

to the under surface of a decaying log of wood, from the

dead leaves on which it was lying.

Figure 100. Flamtnuta sapinca growing on dead leaves.

The fine white threads of the mycelium or true fungus

plant are seen in the soil, and also attached to the stalk of

one of the toadstools which has been pulled up.

Figure 103. The Horse Mushroom {Psalliota arvensis).

Specimens found growing in a garden in the middle of

London.

Figure 101. I'he Stumptuft (Armillaria mellea).

I 'i \m. Voting, imperfectlj expanded specimens of
the Stumptufl (Armillaria mellea).

I

KNOWLF DG1 .

May. 1015.

i i;i 105. riie Champignon, oi Fairy-ring roadstool
Warastnius orectdes).

FIGURE 10S. Fairy ring "1 Citllybia niiicidata growin
mi dead leaves in a wood.

"OtwSI

FIGURE 106. Toadstools from a fairy ring of
Marasmius arcades.

FIGURE 109. A fairy ring of St. George's Mushroom
(Tricholoma gambosum) with a ring of thistles growing

just inside it.

FlGl Lactarius rufus, a toadstoolecontaining a

inch exudes when the fungus is injured.

Figure llo. l'art of a very large ring iii St. George s
Mushroom (Tricholoma gambosum).

May, 1915.

KNOWLEDGE.

133

and richer growth of the grass in their neighbour-
hood. The explanation of the phenomenon is very
simple. The fungus plant gets a foothold in the
soil in many cases, it is thought, owing to the
local manuring of the ground by the droppings of
some animal. In due course in the autumn, or in
the case of the St. George's Mushroom (Triclioloma
gambosum) (see Figure 110) in the spring, a crop
of toadstools is produced, and the nourishment of
the soil in this area being largely exhausted, the
mycelium spreads out in all directions in search of
fresh supplies. The result is that next autumn
a small ring of toadstools is produced, and, provided
that the character of the soil is uniform, every year
a larger ring will be found. It is probable that the
richer growth and darker colour of the grass are
due to the manuring of the soil hy the decayed
toadstools of the previous autumn. A friend has
told me that he has noticed that a ring of Cham-
pignons, or Fairy-ring Toadstools [Marasmius
oreades) (see Figure 105) which is growing on his
lawn gets a little larger every yea r . When the rings
become very large they sometimes cease to extend,
and are even said occasionally to get smaller again.
Any change in the character of the soil will, of
course, tend to break up a ring by producing
unequal growth in different regions, and for this
reason fairy-rings are but rarely seen excepting
where the soil is very uniform ; where the soil
changes, or where two rings intersect, they often
become broken up. Figure 109 is interesting :
it shows a ring of thistles growing just inside a
ring of the St. George's Mushroom. I have seen
many such rings on the downs, near Lulworth. It
may be that there is some symbiotic relationship
between the thistle and the fungus by which the
growth of the one helps that of the other, or it may
be simply that the seeds of each year's crop of
thistles are able to germinate more freely in the soil
broken up and manured by the toadstools.

Most wonderful stories are told of the lifting
power of growing mushrooms and toadstools.
There is an asphalt path in a London garden some
part of which is raised every year by a crop of Horse
Mushrooms (Psalliota arvensis) (see Figure 103).
It is indeed curious that such evanescent and fragile
structures as mushrooms and toadstools should
be capable of exerting such force. The growth
of a mushroom depends on the rapid transference
of material from the mushroom plant or mycelium
to its growing "fruit." The rapidly growing cells of
this attract to themselves large quantities of food
matter and fluid which exude into them by osmosis,
and by the pressure thus exerted the work is done.

In cellular structure the fungi differ essentially
from most ordinary plants : instead of being
formed by polygonal cells pressed together in the
form of a mosaic, the tissues of the fungi are com-
posed of elongated tubes, divided in some cases
by septa, which ramify in different directions,
and are_!_more or less easily separated from one

another. The spaces between these tubes axe
filled in with a certain amount of connecting
material and by air. Sometimes cross-connections
are seen between parallel tubes, so that a figure
resembling a capital " H " is formed. When
divisions occur in the tubes dividing them into cells,
little projections are sometimes seen which connect
the two adjoining cells : these are spoken of as
clamp-connections. Some fungi also possess much
larger branched cells, which contain a milky fluid.
The fluid is in some cases clear, but usually white
and milk-like, and is sometimes coloured. In
Lactariits deliciosus the milk is orange-red. The
i-enera Lactariits, Mycsna, and Fislulina all possess
this latex, or milky fluid. In some species of
Lactarius (see Figure 107) it is acrid and un-
pleasant to the taste, and contains a resinous sub-
stance. The fluid is probably protective in function,
and exudes freely when the fungus is injured.
The fact that the cells containing it are most
abundant on the surface of the stalk and in the
neighbourhood of the gills, regions where any injury
would be especiallv harmful, makes this supposition
the more probable.

Fungi have occasionally been observed to give
forth a phosphorescent light of a pale yellow or
greenish colour. It has been observed especially in
connection with Australian species ; and although
in some cases it may be due to bacterial action
from commencing putrefaction, in most cases it
is the fungus itself which gives forth the light.
The light is usually most intense where rapid
growth is taking place, as, for instance, at the edge
of the cap, and has been noticed in the toadstools
and mycelia of white spored varieties more than in
any other forms. But it has also been seen in rhizo-
morphs, and especially in Corticiion cocriilcum,
which forms blue films on decaying wood.

Fungi are very widely distributed in nature,
and turn up sometimes in most unexpected places.
Even at the rocky summit of the highest moun-
tains they are to be found as one of the partners
of the joint-stock firms of plants which we call
" lichens." M. C. Cooke tells us that about sixty-
four per cent, of the larger fungi are terrestrial,
about seven per cent, grow on dead leaves, and
about twenty-nine per cent, are found on wood ;
and, of course, each special locality has its individual
fungus flora. Because a fungus is found growing
on the ground it is by no means certain that it
is obtaining its nourishment from the ground, for
it may be attached by visible or invisible threads of
mycelium to a dead stump or the root of a tree
on which the fungus plant is growing. A few of the
habitats of various types oi fungus arc seen in the
accompanying photographs (sec Figures 1 1 1 to 1 13).
Some varieties arc very exclusive. Claudopus
variabilis (sec Figure 114) is generally found
growing on dead grass. Collybia conigena (see
Figured 15) grows almost exclusively on the cones
of firs, and not a few parasitic fungi are confined to

134

KNOWLEDGE.

May, 1915.

one species of plant. Indeed, in some of the smaller
parasites, specialisation has gone so far that a given
fungus will only grow on a single variety of host
plant.

The ecology ot fungi, or their relationship to
the environment in which they grow, is a subject
about which little is known. Toadstools >eem less
influenced by the mineral character of the soil
than by the other plants which are growing with
them. The Morel {Morchella esculenta) (see
Figure I Id) is, however, to some extent confined to
limestone districts. Every variety of wood has its
definite fungus flora, which is fairly constant from
year to year. The toadstools met with in a pinewood
are very different from those found in an ordinary
mixed wood, but in both wc find the same species
coming up at approximately the same spot year
after year. Should, however, any change in the
character of the wood take place, such as the cutting
down of a number of the trees or extensive removal
of the undergrowth, a great change in the fungus
flora is at once to be noticed. Generally it may be
said that the presence of thick brushwood seems to
interfere with the development and growth of
fungi. The constant association of certain toad-
stools and certain trees, as, for instance, the Fly
Agaric {Amanita uiuscaria) (see Figure 119), which
is almost exclusively found near birch trees, sug-
gests that there may be some symbiotic relation-
ship between the two plants by which one is of
some assistance to the other. Massee is of opinion
that the mycelium of black -spored toadstools is
destroyed by that of toadstools with lighter-coloured
spores, or that, at any rate, its growth is much
interfered with. But I have seen a variety of
Coprinus with black spores growing apparently
happily on the same log with white-spored species.
Sometimes four or five different varieties of toad-
stool are seen on the same decaying tree, and one
would very much like to know how the mycelium
of each is behaving with regard to that of the
others. Two species of Poly poms (P. ignatarius and
P. dryadcus) both grow on the oak parasitically.
When growing alone, each absorbs the starch
contained in the medullary rays, as well as the
lignin of the wood ; but when the oak is infected
by both together, the starch of the medullary rays
remains intact, although the lignin is absorbed.
Why this is nobody knows.

Fungi are not infrequently to be found in most
unexpected places, and some seem almost invari-
ably associated with human habitations. When
a waterpipe bursts inside a house, or the rain comes
in through the roof, a wet place is seen on the wall
or ceiling. If the leak is not attended to, and the
area remains damp for several days, a pink or
pale brown discoloration soon becomes visible,
especially if the affected area is whitewashed or
plastered. If the discoloration is examined care-
fully, and especially if a pocket lens is used, it will
be noticed that the colour is due to a number of

minute raised spots, all of about the same size.
These spots are the fructifications of a tiny fungus
(Pcziza domestica) which appears to grow exclu-
sively on a moist whitewashed surface. Another
fungus, which we sometimes meet with to our cost,
is the Dry-rot Fungus [Merulius lacrymans) (see
Figure 1 17). The " lacrymans " part of the name
refers, not to the tears of the householder — appro-
priate as they may be — but rather to the large clear
drops of moisture which are exuded from the fruit
of the fungus. Often the first indication that we
have of the presence of the dry-rot fungus is the
repeated appearance of a fine brown dust which
comes into the room through a crack in the floor
or wainscot, and is in reality some of the spores
given off from the fructification. A little later on
the woodwork may appear moist, or, if covered by
paint, a certain amount of warping may be noticed,
or even at times the first thing that may be observed
is that the floor gives way, and somebody's foot
nearly goes through. The fungus grows best in
dark, moist, unventilated places ; but even where
such areas are dry the plant, spreading from
moist soil or brickwork, may carry sufficient
moisture with it to destroy the timber or woodwork
which it invades. Wood that is infected by the
fungus is either moist, soft, and reddish brown in
colour, or else dry, brown, and powdery, and much
lighter in weight than ordinary wood ; and in any
case, whether wet or dry, it is much more brittle
than healthy timber. The mycelium of the fungus
is white and silky : it may sometimes be seen
spreading over the surface of boxes or woodwork
in dark cellars. Apart from the dwellings of man
the fungus is rarely seen, but I have once met with
its fruit growing on a forest tree. For a long time
all attempts to induce the spores of the dry-rot
fungus to germinate experimentally proved un-
successful, but when the nutritive medium was
made faintly alkaline by the addition of ammonia,
the spores grew readily ; and it is probable that
ammonia is very often present in minute quantities
in the atmosphere of the dark, unventilated spots
where the fungus has its home.

A group of fungi which I found growing from a
roof of a London cellar is seen in Figure 121.
These were hanging downwards, and the attempt
made by the plant to get its gills into the vertical
plane, so that its spores may be satisfactorily
shed, is clearly seen in the photograph. Clitocybe
tabescens is not exclusively found in connection with
mankind. It grows also in the forest on decaying
wood.

There would seem to be no very hard-and-fast
line of division between fungi which live exclusively
on dead material and those which are capable of
attacking living animals and plants. Not a few
seem to be able to grow equally successfully as
saprophytes and parasites. A good many parasitic
fungi are in nature confined to a single species of
plant, but it has been found possible in some cases

M . 1115

KNOWLEDGE .

135

Figure 111. Psilocybe caiiobrunnca, a toadstool that
is found in open fields.

Figure 114. Claudopus variabilis, a small fungus
usually found growing on dead grass.

Figure 112. "Blewits" (Trickoloma n udum), a toadstool
which grows on dead le ives.

Figure 115. Collybia conigcna, found exclusively on
pine cones and pine needles.

Figure 113. ["he Sulphur-tufl (Hypholoma fasciculare),
toadstool that grows on dead wood and buried stump

FlGURl 116. 1 In

more abundant, as

morel (Morchella esculent a), much
a rule, on limestone than on other soil.

KNOWLEDGE

M \v. 1915.

p^ -3fe*

gfc.

HP^L, v

»■"■■*

■3?F ;; ■''

siP^Jk Vj

1

1*£

G#w

Hi

I

*Jb

.

T -*f

ffl*.*?^ ••> Ti

"

JffV-j

■ J

~igukb 117. Fructification ol a Dry-rot Fungus (Merulius
lacrymans).

FIGURE lit), homes annosus, a parasitic fungus which
causes a good deal of disease in timber-producing trees.

Figure 118. The Beechtuft (Armillaria
mucida) growing on a beech trunk.

FIGURE 121. Clitocybc tabcsccns. Specimens
found growing in a dark cellar.

FIGURE 11 t. The Fly Agaric (Amanita muscaria) is
almost exclusively found near birch trees.

Figure 122, The Beechtuft (Armillaria mucida).

May, 1915.

KNOWLEDGE.

137

to produce experimentally a variety or strain of
some of them which is capable of attacking a second
plant, by injecting the juices of the first into the
tissues of the second. After several generations of
this treatment the fungus has been rendered capable
of attacking the second host directly. Massee
has also experimentally induced a saprophytic
fungus to become parasitic. Trichothecium cand.id.um
is only found in nature growing on dead substances.
But by injecting sugar into the leaves of a Begonia
this fungus has been induced to attack the plant,
grow on it, and produce normal spores. Spores of
the second generation were sown on another Begonia
plant in exactly the same manner, except that less
sugar was injected into its leaves, and the experi-
ment was continued until, after twelve generations,
a strain of Trichothecium was produced capable of
infecting a Begonia leaf directly without the pre-
vious injection of any sugar at all. It has also been
shown that plants normally immune to infection by
certain fungi may become susceptible if they are
first injured. It is probable that a good many fungi
which are found growing on living trees usually
obtain a footing in the tissues of the tree by attack-
ing a branch injured by wind or storm. The beech-
tuft (Armillaria mucida) (see Figures 118 and 122)
— a beautiful ivory-white toadstool found growing
on living beech trees, often in great abundance —
is an instance of this. All appearances indicate
that it is definitely parasitic in nature ; but, though

Fischer was able to cultivate it from its spores,
and get it to produce fructifications while growing
on sterilised bread and beech wood, all attempts
which he made to infect living beech trees failed
entirely. Probably in nature the fungus only grows
on beech trees which have been prepared for it by
the growth of some other fungus, or it may be that
it starts growth as a saprophyte on some dead
branch, and then obtains sufficient vigour to attack
the living parts of the tree.

There appears to be no doubt at all that Fomcs
annosus (see Figure 120) is a true parasite on living
trees. The mycelium is found between the wood
and the bark of the roots and lower part of the
stem in fir trees as a layer of fine, silky threads,
which can be seen through a crack in the bark
bulging outward. The mycelium secretes a fer-
ment which dissolves out the lignin from the wood
of the lower part of the trunk of the tree, and in
time makes it hollow ; indeed, foresters are able
to recognise the presence of the parasite before
any great change takes place in the general nutrition
of the tree by the hollow sound produced when the
tree is struck. The fructifications of the fungus,
which take the form of somewhat irregularly
shaped projections composed of masses of fine,
vertical tubes open below, are generally borne
on the exposed roots of the infected trees, and are
often seen where the roots have been laid bare by
the burrows of foxes and rabbits.

(To be continued.)

SCIENCE IN THE DAILY PRESS.

Recently Professor R. A. Gregory, the Assistant Editor
of Nature, read a paper before the Circle of Scientific,
Technical, and Commercial Journalists, in which he con-
sidered the accuracy of statements which appear in the
newspapers and weekly periodicals, and discussed literary
and scientific writers, as well as some public beliefs which
have been shown to be erroneous. He said : " It is scarcely
too much to say that, omitting signed articles written by
experts, few newspapers make any announcement relating
to a scientific subject without committing a mistake. Either
terms are wrongly used, or a matter of common knowledge
among men of science is regarded as a remarkable discovery,
or observations of a sensational kind are presented to the
public as if they were established truths, though they
await confirmation from the scientific world, and are mostly
unworthy of serious consideration.

" It seems to be too much to expect literary people to
possess an elementary knowledge of science, or to have any
sympathy with scientific precision, but it is not unreasonable
to ask for accuracy of description when they are dealing
with natural facts and phenomena.

" We are often told that men of science should cultivate
the art of literary expression, but the stronger necessity for
literary men to have at least a nodding acquaintance with
the outstanding facts of natural knowledge is overlooked.
The first business of the man of science is to create new
knowledge, and not necessarily to clothe his discoveries
in a pleasing dress, though he may do so."

Two examples were given by Professor Gregory where
scientific enquiry had failed to support popular opinion.
One was alleged change of climate, and the other the con-

nection between the Moon and the weather. When meteor-
ological records are examined they show that the temper-
ature, rain, frost, and so on, are much the same at the
present time as they were in the early days of the declining
generation. Moreover, " from an examination of old records,
and of the long series of observations made at Greenwich.
Sir John Moore was able to show to the British Association,
in 1908, that no appreciable change has taken place in
the climate of the British Isles during the past six
cent unes.

"The only definite association that can be regarded as
established between changes ol the Moon and weather
is that thunderstorms are slightly more frequent near New
Moon and the First Quarter than near Full Moon and the
Last Quarter ; and it is noteworthy that this is overlooked
completely in proverbial philosophy."

Other fallacies touched upon were that the noise of guns
causes ram, that there is ll.une from a volcano, and living
toads and ln>gs are found in blocks oi coal and other rock,
or that there is such a thing as a thunderbolt.

With regard to the last part of his subject, Professor
Gregory said that " the public likes to believe that men of
science predicted from theory that this or that thing was
impossible whit h \v. is afterwards achieved ; and its literary
guides usually associate a great discovery, not with the man
whose work in the laboratory oi study led to it. but to the
man who made a commercial success of it. It was the
mathematical work of Clerk Maxwell and the scientific
experiments of lleitz which produced wireless telegraphy.
but to the popular press the only man responsible for this
wonderful discovery is Mr. Marconi."

CHAPTERS IN SPECTRUM ANALYSIS.

By W. MARSHALL WATTS, D.Sc.

I. — Law and Order in Spectra.

A. Line Spectra.

(Continued from page 101.)

In the spectrum of lithium, besides the principal
series, three other series have been observed.
Two of these — the " diffuse " (or first subordinate)
and the " sharp " (or second subordinate) series
have the same convergence-frequency at 28579-35.
The formula for the diffuse series is : —

O.F. = 28579-35 -

109675

w+ i.ooii7-: 005}{8 ) 2

m I

and that for the sharp series is
O.F. = 28579-35

109675

m + -602191 -

•013039\ 2

in

The Diffuse Series in Lithium.

t)l.

Observed.

Calculated.

O— C.

1

6103-83

6103-81

+ -02

3

4602-37

4602 -38

- -ill

4

4132-44

4132-49

- -05

5

3915-39

3915-45

- -06

6

3795-18

3795-13

+ -05

'

3719-0

372117

-217

8

3670-6

3672-01

— 141

The Sharp Series in Lithium.

m.

Observed.

Calculated.

O— C.

2
3
4
5
6

8127-17
4972-11
4273-44
3985-86
3838-3

8127-17
4972-12
4273-46

3985-89
3836-01

- -01

- -02

- -03
+ 2-3

Certain remarkable relationships between the
different series have been observed, which show
that they are not independent of each other.
If, for brevity, we denote the three series by
P, D, and S, and their convergence-frequencies
by Poo, Deo, and Soo, the first relationship is
that Doo = Soo.

In the next place Poo - Soo gives the oscillation-
frequency (P 2 ) of the principal series. Thus in
lithium Poo =43482-52
Soo =28579-35

P 2 =14903-17

The following are the observed values of this line :—

6708-0 Ramage, in flame.

6708-2 Kayser and Runge, in arc.

6708-10 Exner and Haschek, in arc.

6708-2 Edcr and Valenta, in spark.

6708-09 Exner and Haschek, in spark.

This relationship was discovered independently by
Rydberg and by Schuster, and is generally called
the " Rydberg-Schuster Law." This law probably
holds good for all elements. It is interesting to
note that in 1896 Schuster predicted that a pair of
caesium lines, at about 8908 and 8518, would be
found in the infra-red — a prediction verified by

the discovery of the pair j 0=97.70 by Lehmann in

1901. A " diffuse " series and a "sharp" series exist
in the spectra of sodium, potassium, rubidium, and
caesium, each series consisting of pairs of lines,
as in the corresponding principal series. These
subordinate series have the pairs of lines always
at the same distance apart, as measured in
oscillation-frequency, whereas in the principal
series they get closer and closer together as they
approach the convergence-frequency. Further,
the constant difference in the two subordinate
series is exactly that of the first pair in the principal
series. This difference is 17-19 for sodium, 57-87
for potassium, 237-98 for rubidium, and 553-96
for caesium, these numbers being approximately
as the squares of the atomic weights of the corre-
sponding elements.

In sodium the common convergence-frequency of
the diffuse and sharp series is 24475-89 for the less
refrangible lines, and 24475-89+17-19=24493-08
for the more refrangible lines. If we subtract
these numbers from 41448-67, the convergence-
frequency of the principal series, we get 16972 - 78
and 16955-59 as the oscillation-frequencies of the
two P„ lines, and these correspond to the wave-
lengths" 5890-19 and 5896-16 respectively. The
observed values of these lines are :

5806-16 K avser an d Runge, in the arc.

58Q6-T4 Rowland, in the sun.

which corresponds to the wave-length 6708-16.

5890-18)
5896- 15J

5896 -?7 1 E xner an< ^ Haschek, in the arc.

5890-21

5896

Eder and Valenta, in the arc.

.91 -\
To} Exner and Haschek, in the spark.

U8

May. 191 f

KNOWLEDGE.

139

.

Sodium and Lithium. Flame Spectrum.

i

Lithium Spark. Spectrum.

a ;■ S
Zinc Spark. Spectrum.

/.><• 14 . ■ iSlf

Cadmium Spark. Spectrum.

Ol* III! •

U,i !(••>

ililiiiiljiiilnnliiftliii]liii i liii

tt, y s

a, (,u

Coppe] ( Monde, hii.ii i. S] i eti urn,

!-••>

3 5

* Y

Coppei I iii' 'i ide. Fla me Spectrum.
1 i .i i i 123.
(After Lecoq de Boisbaudi

140

KNOWLEDGE.

May, 1915.

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May, 1915.

KNOWLEDGE.

141

In potassium the common convergence-frequency
of the two subordinate series is 21967-5 for the
less refrangible lines, and 22025-37 for the more
refrangible lines of the pairs. Subtracting these
numbers from 35005-56, the convergence-frequency
of the principal series, we get 1 3038-06, and 1 2980-1 9
for the two P 2 red lines ; and these numbers
correspond to the wave-lengths 7667-77 and 7701 -96
respectively. The observed values of these lines
are :

7668-54) T .

7701 •9'> Lehmann, in the arc.

7665-61 ,, , „

7699-3/ Jva y ser an " Runge, in the arc.

7699 ! ^er an d Valenta, in the flame.

For rubidium the mean convergence-frequencies
of the subordinate series are 20872-7 and 21 1 10-68
and Poo = 33688-20. These numbers give

P2=jnnip.5 )> the observed values being:
1 7947-7 ( ^er an< ^ Valenta," in the arc.
7nf7 a" Saunders, in the arc.

I 7947-6J

For caesium the corresponding numbers are
19672-9 and 20226-86 and Poo =31404-6. These

numbers give P 2 =i omT.-v;, > the observed values

\ 8943-96 J

Lehmann, in the arc.

, . | 8527-50 |
«*ing l8949 .G7l

Here the correspondence is not quite so good :
a result to be expected perhaps from the difficulty
of determining accurately the wave-lengths of
lines lying far in the infra-red.

The observation that the pairs of lines in the
subordinate series have the same difference in
oscillation-frequency is important. In the case
of sodium the interval 17-2 occurs twenty-three
times; in potassium the interval 57-9 occurs
thirteen times, and the interval 238- occurs sixteen
times in rubidium. These are instances of what is
known as the " law of constant differences,"
discovered by Hartley, who observed (in 1883)
that three triplets in the spectrum of zinc corre-
sponded with three triplets in the spectrum of

cadmium, and that in each of these spectra the
triplets have their lines equally spaced if mapped
on the scales of oscillation-frequency. The photo-
graphic reproduction of Lecoq de Boisbaudran's
drawings of the spectra of zinc and cadmium shows
these triplets plainly (see Figure 123). Such triplets
characterise the spectra of magnesium, calcium,
strontium, zinc, cadmium, and mercury, the " scale "
on which the triplets are spaced being proportional,
more or less nearly, to the squares of the atomic
weights.

In the reproduction of Lecoq dc Boisbaudran's
spectra of zinc and cadmium the first triplets of
the sharp series are marked «, y, 8 and a, /3, 6
respectively. The wave-lengths and oscillation-
frequencies [in vacuo) of these lines are :

In Zinc.

Wave-
length.
4810-75
4722-36
4680-35

Oscillation-

frequencv.

20781-081

21170-06 Difference 579-00

21360-08'

In Cadmium.

5086-08
4800-11
4678-37

... 19656-52,

,.. 20827-17} Difference 1712-60

... 21369-121

If these differences are proportional to the squares
of the atomic weights, we can calculate that of
zinc from that of cadmium, namely. 112-40;
making the calculation we obtain for zinc the number
65-358, whereas the atomic weight of zinc deter-
mined by chemical methods is given in the Inter-
national Table for 1915 as 65-37.

The diagram which accompanies this article
(see Figure 124) is a reproduction of the diagram
given by Kayser and Rungc in their paper of 1890,
and shows the spectra of the alkalies as known
at that time. The spectra are mapped upon the
scale of oscillation-frequencies, and the scale of
wave-lengths is also shown under each element.
The complete spectrum i- shown in the top line.
the next line shows the principal series, the third
line shows the diffuse series, and the fourth line
the -harp series. The scale of the drawing is too
small to allow of the pairs of lines being properly
represented : they are shown too far apart.

[To be continued.)

KHAKI DYH.

The present shortage in this country oi synthetic yellow
dyes has put considerable difficulties in the way of manu-
facturers of khaki cloth. A temporary way out of the
trouble was found, however, by the increased u
fustic, a natural yellow dyestufl, consisting of the wood o)
a tree {Chlorophora inutoria) which grows freely in Jamaica
and also in British Honduras. At the outbreak of the
war there was only a small supply available in Europe,
though fortunately one of the prizes captured from ( lermanv
had a considerable consignment on board. A certain
amount, too, has been obtained from France, which country
and the United States have hitherto taken the bulk of the

fustic exported from Jamaica, When the shortage of
yellow dyestuffs in tins country lirst became apparent the
imperial institute took steps to place British dye tinns in
touch with exporters oi fustic in Jamaii a Only a moderate

amount ol CUl fustic wood was, as it happened, then avail-
able in the island, but as a result "t the Institute's action
the Government >>t Jamaica has offered to purchase from
the growers further supplies, and carry these, at Govern-
ment cost, to Kingston, the pert .>t shipment. The Govern-
ment of British Honduras is also taking action in this
matter, and a further supply of the wood may possibly be
forthcoming from that colony.

GERMAN SCIENCE.

By Prof. J. ARTHUR THOMSON. M.A., LL.D.

A comparative survey oi the scientific pro-
ductivity of different nationalities, such as we have
attempted in some detail in a contribution to the
symposium entitled " German Culture " (Jacks,
1015), is obviously beset with great difficulties.
One of these is involved in tin- fa< I that a nationality
i> made up oi various racial strains, differing widely
in their scientific and other qualities. To take
a familiar illustration, how is the historian of
biological science to be sure how many oi the
famous physiologists and pathologists of Germany
must be ranked racially a- Jews ? There have also
been potent immigrations, well represented by
such men as the physiologist Haller, the botanist
Nageli, the zoologist Kolliker, the mathematician
Euler, who were identified with Germany in their
life and labours, but belonged by birth to Switzer-
land. Another difficulty in comparison is that,
after we have taken account of the few giants
whom all the world acknowledges, we encounter
extraordinary differences of opinion as to the merits
of even famous investigators. Thus in the history
of science some will attach considerable importance —
rightly, we think — to Goethe, and others none at all.
Some will compare Haeckel with Huxley, while
others regard him as quite second class. Some
will compare Ehrlich and Almroth Wright, Koch
and Pasteur, while others regard the collocations
as far from felicitous. Some will compare Helm-
holtz and Kelvin. Kirchhoff and J. J. Thomson,
Hertz and Fitzgerald, while others regard this as
betraying a loss of perspective. The reasons for
this divergence of opinion are several. " Every
man for his own country " is one ; another is that
there are several distinct species of scientific dis-
coverer ; and a third is that while one valuator
is thinking of the investigator's mental ability.
another is considering the influence that his teaching
or his published work has had on the development
of science. There is a further difficulty in a com-
parative valuation, conducted in public, that not a
few of the very greatest names are quite unfamiliar
even to the omniscient general reader. Thus,
to take a diagrammatic illustration from the
essay already mentioned, we believe it to be true
that the names of Green (1793-1841), Galois
(1811-1830), and Gauss (1777-1855) stand for
mathematical achievements of the very highest
order, but how few outside of the ranks of mathe-
maticians know anything about these three geniuses,
or any one of them ! We doubt if Green has even
the honour of an article in the " Encyclopaedia
Britannica " ! Marconi is much better known than
Galvani, and Edison than Willard Gibbs ; and it
is quite natural that it should be so. The work
of those who lay foundations is rarely known to

spectators ; it is not rightly appreciated save by
the greater builders.

One of the impressions that we get from a geo-
graphical survey of scientific productivity is
that of the widespread distribution of discoverers.
Wherever two or three are gathered together in
the name of Pallas, there the revealing spirit is at
work. Nor is the solitary devotee left unrewarded.
To think of Italy is to remember Galileo and
Galvani, Volta and Veronese, Avogadro and
Borelli, Cannizzaro and Spallanzani, to take the
names as they tumble out. Russia recalls von
Baer, one of the few very great minds who have
given their life to Biology ; Kowalevsky, who
discovered the affinities of Ascidians ; Metschnikoff,
with his far-reaching theory of phagocytes and
inflammation ; Mendeleeff, with his Periodic Law ;
the mathematical genius Lobachevski ; the physio-
logist Pavloff, and many other investigators of
extraordinary brilliance. We cannot pass to
Poland without thinking of the scientific chain
linking Madame Curie (Marie Sklodowska) to Coper-
nicus, or of the wonderful family of the Bolyai.
Austria makes one think of Mendel, whose work has
changed all our thinking in regard to heredity,
and of the Viennese school of medicine which
began with Rokitansky. Sweden was the home
of Linnaeus and of a succession of great chemists
from Berzelius to Arrhemus. Speaking of chemists
reminds us of the great part Holland has recently 7
played through Van 't Hoff and Van der Waals,
and Belgium through Le Bel. The Dutch con-
tributions to physical science have been of high
importance from Huygens — more or less con-
temporary with Newton — to Lorentz of to-day.
One other reference must suffice, and that not to
Britain, France, or Germany 7 , which have each
their galaxy of great investigators, but to the small
country of Switzerland, with Haller as physiologist,
Louis Agassiz as palaeontologist, Kolliker as
zoologist, Euler and the Bernoullis as mathe-
maticians, Nageli as botanist, and so on. In fact,
every civilised country has its scientific roll of
honour, though in some cases it is no longer than
it should be.

A second impression that we get from an im-
partial comparative study is that Britain, France,
and Germany run neck and neck. If we take a
series of more or less analogous names, without
attaching too much importance to this rough-and-
ready method, we see that the balance dips now
to one side and now to another. If we could, as we
cannot, represent the merits of three counterparts —
British, French, and German — by the three sides
of a triangle, the lengths would now be in favour
of Britain, again in favour of France, and again in

142

May, 1915.

KNOWLEDGE.

143

favour of Germany ; yet a superposition of a
number of triangles sufficiently large to get rid
of conspicuous inequalities would yield a not very
irregular figure. This, at least, is one of the con-
clusions arrived at in the detailed essay we have
cited. Let us take a few examples, the British
representatives being alphabetically arranged.

British.

French.

German.

Balfour, F M.

Lacaze-Duthiers

Roux

Dalton

Lavoisier

Bunsen

Darwin

Lamarck

Kepler

Davy

Legendre

Weber

Faraday

Fourier

Clausius

Fitzgerald

Becquerel

Hertz

Foster

Claude Bernard

Ludwig

Galton

Delage

Weismann

Graham

Berthelot

Liebig

Green

Galois

Gauss

Hunter

Cuvier

Gegenbaur

Harvey

Bichat

Humboldt

Hooker

A. de Jussieu

Sachs

Huxley

Buff on

Haeckel

Joule

Carnot

Mayer

Jenner

Bordet

Behring

Kelvin

Laplace

Helmholtz

Lankestcr

Giard

Johannes Miiller

Lister

Pasteur

Virchow

Lodge

Ampdre

Ohm

Maxwell, Clerk

Poincard

Boltzmann

Ross

Laveran

Koch

Burdon- Sanderson

Brown-S6quard

Bois-Reymond

Spencer

Bergson

Lotze

Smith, Wm.

Gaudry

Suess

Stokes

Lagrange

Cantor

Thomson, J. J.

Cauchy

Kirchhoff

Weldon

Quetelet

Zittel

Wright, Almroth

Richet

Ehrlich

Another impression produced by a detailed survey
is that there are distinctive features in the scientific
output of the different nationalities. There are a
few French-like Englishmen and a larger number
who are German-like, and so forth, but on the whole
there are definable characteristics. British work
seems, not unnaturally, to be marked by its sanity,
its true perspective, its self-criticism, and its
evidence of having been done for its own sake.
French science is distinguished by clearness both of
style and vision, by individuality, originality, and
defiance of traditions. German investigators are
characterised by thoroughness, learning, orderliness,
careful technique, and a convinced belief in the
value of science as a whole, and of their own
contributions in particular. The persistence with
which one investigator will give almost the whole
of his life to the study of the dogfish head, or another
to the nerve cell, or a third to centipedes, with
occasional holidays among millepedes, is colossal.
There have been changes within recent years,
but many German investigators have held firmly
to the old tradition of devotedness to the task
undertaken, of plain living and high thinking, and
of industrious productivity. But besides the

tradition there is the temperament, accentuated
by habit, of strenuous persistence. They have in
high development that quality to which Darwin
referred in himself when he said, " It's dogged that
does it." No doubt the German investigators,
like others, have the defects of their qualities.
The demand for output has often led to hasty and
purely quantitative work, or the extreme specialism
to a loss of perspective, or the standard of thorough-
ness to tedious prolixity. In other nationalities
there is a wholesome prejudice against longwinded-
ness in science, against pushing detailed description
beyond the limit of probable utility ; but it is
characteristic of descriptive science in Germany to
recognise no limit but that of the available analytic
methods of the day. There is, to be sure, something
fine in this, and if it be sometimes a rather ridiculous
little mouse that the mountain brings forth, it is
usually an irrefutable mouse that has come to
stay.

It has been repeatedly asserted during recent
months that German science is largely derivative,
and that German investigators get hold of the ideas
of others, and work them out. This is probably true
in regard to certain lines of investigation, just as
for others it is true of Britain, Russia, America,
and the rest. It is least true of France ; but the fact
is, that there has been continual cross-fertilisation in
the evolution of science. Even if it be admitted that
Germany has seen the birth of fewer big scientific
ideas than France or Britain — which is doubtful —
credit is due to investigators who have detected the
promise of dormant seeds, and have brought
them to development. To those who remind us
that Hertz, for instance, stood on the shoulders
of Fitzgerald, it may be answered that Bateson
stands on the shoulders of Mendel ; and both state-
ments would be ridiculously farjji off adequate
accuracy. If it be maintained that the foundation-
stones of the theory of electricity have been
mainly laid in Britain, is it not equally legitimate
and futile to point to Germany as the cradle and
home of cellular biology ? And if we are asked how
we can for a moment venture to compare German
geologists with those of England and Scotland.
we wait till the triumphant questioner discovers
that, although Suess was born in London, and spent
most of his life in Austria, he claimed Saxony as his
fatherland. This sort of historical retort might
be repeated twenty times over without being far-
fetched. When we think of men like Suess. or Helm-
holtz, or Goethe, or Johannes Miiller (to take a few
outstanding names), we see the inaccuracy and
arrogance of maintaining that the supreme title of
genius is inapplicable to German investigators.
What appears to be the truth is this, that each of
the leading civilised nations has its fair share of
scientific discoveries of first-rate importance, but
that there is no sufficient evidence for correlating
special fertility in scientific discovery with any
nationality. Speaking now, not of men of

1 It

KNOWLEDGE.

May, 1015.

intellectual eminence, but of the real giants, we
believe that the great discoverers represent indi-
vidual mutations. In its finest expression the dis-
covering spirit means a particular alertness, fresh-
ness, eagerness, insight, and cerebral potential —
born, not made. The spot of light which marks its
emergence shifts from place to place, from nation-
ality to nationalitv. from race to race, from

university to university, shining forth now in Pisa
and again in Paris, now in London and again at
Leyden, now in Brussels and again at Berlin,
now in Edinburgh and again in Petrograd, now
in Amsterdam and again in New York. It is a
rare spirit, sacred and inestimable, and moveth
where it listeth, no one being able to tell whence
it cometh, or whither it goeth.

SOLAR DISTURBANCES DURING MARCH, 1Q15

Bv FRANK C. DENNETT.

With the exception of the 3rd, the Sun was under observ-
ation every day in March, and was never free from spots ;
whilst on the 2nd as many as seven distinct spot disturbances
were visible at one time. The longitude of the central
meridian at noon on March 1st was 34° 8'.

Nos. 18, 20, 21, 23, 24, and 25 of the February list con-
tinued on the disc until March 2nd, 5th, 6th, 10th, 2nd,
and 10th respectively, and therefore reappear upon the
present chart.

N<> 26 appeared as pores a little south-west of No. 23
on the 2nd. The leader increased to seven thousand miles
in diameter, but the others died out. Last seen on the 9th.

No. 27. — A double group of spotlets and pores, constantly
changing their appearance ; seen from the 6th until the
11th. Its greatest length was sixty-four thousand miles.

No. 28. — A line of four or five pores, fifty-seven thousand
miles in length, in a faculic bed ; seen from the 7th until
the 13th.

No. 29.— A fine spot, twenty-one thousand miles in
diameter ; close to the north-eastern limb on the 7th. On
the 9th it appeared triangular ; next day its umbra was
bridged, and two pores followed it. The pores constantly
changed position, and on the 14th a bridge of the photo-
spheric matter entirely crossed the spot from north to
south. Last seen amid faculae, close to the north-western
limb on the 19th.

No. 30. — Broke out on the 14th, close to the central
meridian, the northern spotlet being the largest. Next
day a line of spots and pores. The length was thirty-two
thousand miles, and one of the rear spots became ten
thousand miles in diameter. Last seen close to the limb
on the 20th.

No. 31. — A group of spots and pores very protean in
character, thirty-five thousand miles in length ; seen from
the 17th until the 22nd. It attained its maximum size
on the 20th.

No. 32. — A solitary pore only seen on the 20th.

No. 33. — A curved line of pores in a faculic bed, some
thirty-five thousand miles in length; seen from the 21st
to the 23rd.

No. 34. — A spot some twelve thousand miles in diameter,
first seen on the 23rd. Pores were following it on the 27th,
29th, 30th, and 31st. Last seen on April 2nd. The length
was thirty-four thousand miles.

No. 35.- — A faculic area had been coming round the south-
eastern limb since March 19th, and on the 29th two pores
were seen ; the leader increased to a spotlet by the 30th,
and other spores had developed. The pores not seen after
April 1st, or the spot after the 4th. Its greatest length was
twenty-nine thousand miles.

No. 36. — Two pores, each situated in a facula, fifty-two
thousand miles apart ; only seen on the 29th and 30th.

No. 37. — Altogether the finest group seen for several
years. First seen as a line within the north-eastern limb
on March 29th. Next day it was evident that a considerable
group was formed. At first there was a great leader, over
forty thousand miles in diameter, followed by a group of
spots, which by April 4th had developed into a fine oval
spot, thirty thousand by eighteen thousand miles in
diameter, containing two umbrae. Behind this were some
pores, and a smaller spot bringing up the rear. On April
7th a small spot and pores preceded the great spot, making
the total length of the group one hundred and eighty thou-
sand miles. It was closing up to the limb on April 10th,
the date of the last record to hand. It extended back into
the area of No. 27, and covered that of No. 16.

No. 38. — A group thirty-one thousand miles in length,
consisting of five pores, broke out on March 30th, two of
which remained visible until the next morning, but were not
seen subsequently.

Faculae were recorded within the north-western limb
on March 7th to 10th, 14th, 25th to 27th, and 29th to 31st ;
north-east, 1st, 2nd, 9th, 10th, 16th, 19th to 22nd, 27th,
28th, and 31st; south-west, 6th, 7th, 9th, 11th to 14th,
27th, 30th, and 31st; and south-east, 2nd, 19th to 22nd,
and 26th to 31st.

Our chart is constructed from the combined observa-
tions of Messrs. John McHarg, \Y. J. Waters, and F. C.
Dennett.

DAY OF MARCH, 1915.

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THE CAUSE OF ALBINISM AND DOMINANT

WHITENESS.

Bv H. ONSLOW

For some time biologists have been aware that
white animals may be divided into two distinct
classes : albinos, or recessive whites, and dominant
whites. These two types are visibly, and were
hitherto chemically indistinguishable, being capable
of differentiation only by means of the offspring
which the}' produce. The recessive whites, or
common albinos, are widely distributed among
domesticated animals (e.g., albino mice, rabbits,
guinea- pigs, and so on) : they have pure white fur
and pink eyes, which appear totally devoid of
pigment, but which, on microscopical examination,
are found to contain minute pigment granules.

Let us suppose an albino rabbit is mated to a
self-black rabbit ; all their offspring will be the
same colour as the coloured parent — that is to say,
they will all be black. If these black offspring of
the first, or F lf generation are mated together, they
will have black offspring and white offspring in
the ratio of three black to one white, in accordance
with the simple Mendelian law. The white offspring
will, of course, be pure recessives, like their albino
grandparent, and will produce nothing but albinos
when mated with each other, whereas two thirds of
the black offspring will be heterozygous for albinism
like their parents, and the other third pure black like
their self-black grandparent.

The second type of white animal — dominant
white — is superficially indistinguishable from an
albino, except that the eyes are usually more
heavily pigmented, and occasionally there are
flecks of pigment upon the body. Both types of
white have a correlated piebald form, in which the
white portions of the pattern are respectively
recessive and dominant to self-colour. Now, if
a dominant white rabbit is crossed with a self-
black, all the offspring will be white, instead of
black as in the case of the albino ; and, if the
dominant white is only heterozygous for white-
ness, half the young will be heterozygous dominant
whites like one parent, and the other half will be
self-blacks like the other parent. It will thus be
seen that albinos are recessive to colour, and
dominant whites dominant to colour, as the name
signifies.

The problem, therefore, was to discover what
physical difference underlay this variation in
genetic behaviour.

It has been shown that dark animal pigments,

* During the process of extraction the organic peroxide component of the peroxidase was usually, but not invariably,
destroyed in these experiments. It can, however, be easily replaced by a very small quantity of hydrogen peroxide.

f For this purpose so-called " English " rabbits were used. They are a black-eyed white rabbit with a few coloured
spots on the back and flanks.

I This reaction was not as strong as the previous ones, owing to the fact that the ferment fluid was diluted by as
much as an equal volume of the recessive white extract.

or melanins, are in many cases the result of the
interaction of an oxydase and a chromogen. The
oxydase is generally a tyrosinase, and the chromogen
either tyrosine or a closely allied substance. By
the union of an organic peroxide and a peroxidase
an extremely unstable third substance is formed,
which on decomposition gives its oxygen to the
colourless chromogen, and thereby converts it into
a melanin.

It was found possible to obtain a colourless fluid,
rich in tyrosinase,* by making an extract from the
skins of very young black rabbits. By adding to this
extract a few drops of a saturated aqueous solution
of tyrosine as a substitute for the natural chromogen
(which appears to be destroyed, together with the
organic peroxide, during the process of extraction),
and incubating at blood-temperature for twelve
hours, the mixture becomes oxidised. A deep
black ring forms at the surface of the fluid, where
it is in contact with the atmosphere, indicating
the formation of melanin. Now, if a fluid is
extracted in an exactly similar manner from reces-
sive and from dominant white rabbits, f and if
it is incubated with tyrosine in the same way,
no darkening occurs. This shows that either the
tyrosinase is absent, or, if it is present, its action is
inhibited by some other substance. In order to
test this, varying quantities of the two white
extracts were incubated with an equal quantity
(two cubic centimetres) of an active tyrosinase
solution, tyrosine, and hydrogen peroxide. The
results were as follows : —

+ + Indicates strong reaction.
+ Indicates positive reaction.
— Indicates no change.

Dominant white

Recessive white

Appca ranee

extract.

extract.

after 12 hours.

1

2

0-05 c.c.

—

• +

3

0-25 c.c.

—

+

4

0-5 c.c.

—

—

5

1-0 c.c.

—

—

6

—

0-25 c.c.

+ +

7

—

0-5 c.c.

-f +

8

—

10 c.c.

+ +

9

—

20 c.c.

+:

145

146

KNOWLEDGE

May, 1915

Since no reaction takes place in any of the tubes
which contain as much as twenty per cent, of the
dominant white extract, and since the tubes con-
taining the recessive white extract are all oxidised,

it is clear that the dominant whites are white.
because they contain an inhibitor or anti-tyrosinase,
which prevents the formation of pigment ; and
that the recessive whites are white, because at least
one factor necessary for the formation of the
pigment is absent, namely, tyrosinase. It was
also found possible to isolate this inhibitor by
fully saturating the fluid extract with ammonium
sulphate, when the inhibitor is completely pre-
cipitated.

This account of the chemical cause of the differ-
ence between dominant and recessive whiteness
agrees also with the genetic data ; for, as has
already been said, $ dominant white (with inhibitor)
X ? self-colour (with colour-producing factors) gives
nothing but white offspring; but <? recessive white
(without colour - producing factors) x ? self-colour
(with colour-producing factors) gives nothing but
self-coloured offspring, as would be expected.

The fact that dominant white animals sometimes
have coloured spots or patterns must be explained
by the supposition that in these places the inhibitor,
for some specific reason, has not been deposited
in the skin. No doubt recessive whites are some-
times piebald, for analogous reasons.

The hypothesis that dominant whiteness is
caused by the presence of a chemical inhibitor
in the cells of the skin, which can be transmitted to
the offspring, and which prevents the formation of
pigment, is by no means a new one. It was first
discovered that certain dihydroxyphenols, such as

orcin, had the property of inhibiting the action
of tyrosinase upon tyrosine in vitro. The dominant
white flowers of Primula sinensis also contain an
inhibitor, which can be destroyed by hydrogen
cyanide, after which they will show certain oxydase
reactions with suitable reagents. Certain pale
shades of flowers which are dominant over the
deeper shades have also been thought to be due to
the presence in the petals of deoxidising substances,
such as tannin or sugar ; and, lastly, the colour of
the larvae of Spelerpes bilineatus has been modified
by subjecting the eggs to a dilute solution of orcin.

Figure 125. — A series of tubes containing the skin
extracts, and so on, after twelve hours' in-
cubation.

A. — Extract from black rabbits -f- tyrosine -f-H 2 2 .

B. — Extract from black rabbits -4- tyrosine -4- H 2 2
at room temperature.

C. — Extract from black rabbits -+- tyrosine -4-H a 2
+ extract from dominant white rabbits.

D. — Extract from chocolate rabbits + tyrosine
+ H. 2 2 .

E. — Extract from black rabbits+/>-cresol.

F. — Extract from recessive white rabbits -(-tyro-
sine -|-H 2 0.,.

C shows no sign of oxidation, because it is in-
hibited by the anti-tyrosinase in the dominant
white rabbits, and F shows no oxidation, because
recessive white rabbits contain no tyrosinase.
E is coloured deep pink.

Note the layer of unoxidised fluid at the bottom of
D, where it has not been in contact with the atmo-
sphere. This layer is not so clearly defined in the
other tubes, as they were slightly shaken.

NOTES.

ASTRONOMY.

By A. C. D. Crommelin, B.A., D.Sc.

F.R.A.S.

MELLISH'S COMET has been observed several times.
It has a sharp nucleus, resembling a star, and a considerable
coma surrounding it, the diameter being about 10'. Mr.
W. H. Steavenson traced the tail for half a degree on April
7th. The orbit given last month needs sensible correction.
Perihelion passage will be about July 17-63 G.M.T., and
the logarithm of the perihelion distance is 0-0068.

The following outline ephemeris gives an idea of its
motion from June to October :■ —

Date. R.A. S.Dec. Log. r. Log.A.

1915. h. m. s. o ,

June 17-63 ... 4 5 16 ... 67 28 ... 00552 ... 9-6655
July 17-63 ... 6 6 56 ... 39 37 ... 0-0068 ... 9-9326
Aug. 16-63 ... 6 26 16 ... 28 21 ... 00552 ... 0-0568
Sept. 15-63 ... 6 25 40 ... 21 50 ... 0-1518 ... 00860
Oct. 15-63 ... 5 52 52 ... 16 9 ... 0-2466 ... 0-0706

The path is more favourable for northern observers than
that given last month. Southerners will enjoy the best of
the display, but the comet returns to our zone of visibility
in September, when it may still be a naked-eye object.

Winnecke's Periodic Comet returns to perihelion at the
end of August, and was detected early in April at the Berge-
dorf Observatory, its magnitude being 16.

STELLAR SPECTRA AND TEMPERATURES.—
Messrs. W. S. Adams and A. Kohlschiitter write on this
subject in No. 89 of the Mount Wilson Contributions. It
is taken for granted that the stars of large Proper Motion
are on the average nearer than those of small Proper
Motion. The latter have the violet end of the spectrum
weaker than the former (for the same spectral type) ; also
the hydrogen and a few other lines are relatively stronger
in the small Proper Motion stars. The conclusion is that
these spectral differences do not arise from absorption
in space, but arise from greater atmospheric absorption in
stars of large mass. The small Proper Motion stars, being
more distant than the others, are presumably of greater
mass. Hence there is hope of deducing the absolute mass
and luminosity of stars by careful study of the intensity of
certain lines, and also the relative strength of different
parts of the continuous spectrum. The results have to be
considered in combination with the spectral class to which
the star belongs.

LATE SPECTRA OF NOVAE.— No. 87 of the same
Contributions gives reproductions of photographs of the
spectra of 4 Novae taken with the sixty-inch at Mount
Wilson by Messrs. W. S. Adams and F. G. Pease. They are :
Nova Aurigae, twenty-three years after outburst ; Nova
Persei, t irteen years after; Nova Lacertae, four years after ;

May, 1915.

KNOWLEDGE.

147

ti

Figure 125.
Skin extracts from rabbits (see page 146).

n i » * i r

FlGUKl 126.

Radula . > t Zonites nli vet arum of Moqmti I indon, stained; in Canada b

X about 140 >. i page I

'

KNOWLEDGE.

May, UJ15.

Figure 127. Transverse section of the spine o) Cidaris,
taken witb a one-inch objective. X 70. Exposuie 4 mins.

Figure 129. Arachnoidiscus Ehrenbergii, taken with
a half-inch objective. X 280. Exposure 6 mins.

FIGURE 12S. Transverse section of the spine of Echinus,

taken with a two-third inch objective. X 60. Exposure

3£ mins.

Figure 130. Hcliopcita Metii, taken with a half-inch

objective. X400. Exposure 8 mins.

From photomicrographs by A, Wellesley-H arris, M R C S .
And illustrating his papei on "Some Hint-, on Pboto-micrography " in The Journal of the Photo-micrographic Society.

In all cases, projection ocular No. 4 was used; the illuminant «as incandescent gas and the filter, anramine

(see page 153).

May, 1915.

KNOWLEDGE.

149

Nova (2) Geminorum. two years after. The chief point is
that the nebular lines at 4364, 4960, 5007 have completely
disappeared in the two older Novae ; the last two are still
strong in Nova Lacertae, while all three are strong in Nova
Geminorum. Hence the fading of these lines is characteristic
of the late stage of Novae. At the same time, the continuous
spectrum grows stronger. They suggest, in explanation,
that the initial outburst is due to the star entering a nebula,
and that the nebular lines disappear when the star emerges
from it. There is an obvious difficulty in this suggestion.
It would need a fairly dense nebular to account for the very
sudden outburst of light : such a nebula could hardly fail
to be a violent exciting agent during the whole of the star's
passage through it. But the above Novae had become verv
faint before the nebular lines faded out.

The paper points out that the late stages of Nova spectra
are almost the same as those of Wolf-Rayet stars. It is
suggested that at least some of the latter stars may have
once been Novae.

THE COLLISION HYPOTHESIS OF NOVAE.— Mr.
!■'. A. Lindemann has an article on this subject in
Monthly Xotices for January. Examining whether collision
with a nebula would explain the observed phenomena, he
finds that the pressure of the nebula would have to be
about 1 1000 of a millimetre — Mr. Ranyard had shown that
so high a density is improbable. The objection is also made
that the temperature would increase,, or at least remain
constant, all the time that the star was traversing the
nebula ; but in fact the decline generally sets in very soon.
The hypothesis of collision with a meteor swarm is more
hopeful ; but the author thinks that in this case it would
return rapidly to its condition before the outburst, whereas
the effects on the spectrum persist for many years. He
next deals with the assumption that novae arise from the
collision of star with star. Making the best assumptions
in his power for the various constants involved, he deduces
that the number of dark stars in our system must be about
four thousand times the number of bright ones. If this
be correct, stars remain dark for a much longer period than
they are luminous. The period of luminosity of a star is
supposed to be measured by hundreds of millions of years,
and its dark period would be measured bv billions. Such
matters must always remain highly speculative ; still,
they have a fascination for manv minds, and the time
spent on them is not wasted.

THE SOLAR ECLIPSE OF LAST AUGUST. -
Monthly Notices for January contains the reports of the
observers, with two photographs and a careful drawing,
which shows that the corona was of slightly modified mini-
mum form, differing in the fact that the equatorial streamers
were more spread out than at minimum. Father Cortie
obtained a successful photograph of the coronal spectrum.
Five series of flutings were shown, three in the red and two
in the green ; also several lines, including the characteristic
line in the green at 5303. The sources of the other lines
have not yet been identified. The photographs at Minsk
failed to show the 5303 line, and indicated that the violet
end of the coronal spectrum was unusually faint. The
spectrum of the chromosphere was photographed down
to wave-length 3118 in the ultra-violet. Hoth the
Minsk observers and Father Cortie took an iron comparison
spectrum on their plates, so that accurate measures of wave-
length can be made. On the whole, considering the dis-
turbance due to the war, the observation of the eclipse was
successful ; some of the Russian, French, and Swedish
observers also obtained good results. In particular they
discovered a new bright line in the red part of the coronal
spectrum at wave-length 6374 : this is included in one oi
Father Cortie's bands.

THE ANNUAL REPORT OF THE ROYAL ASTRO-
NOMICAL SOCIETY contains several interesting notes on
the progress of astronomy. Controversy over the solar
constant of radiation continues. Messrs. Abbot, Fowle.

A. K. Angstrom, and E. H. Kennard support the low value
of 1 -93 calories per cm. 2 sec. , while F. W. Very maintains
that it cannot be less than 3, and may reach 4. He
considers that much heat is reflected from the upper air
without reaching the Earth.

F. Schlesinger gives the formula 14 = -17 — 3 3 -4 sin 2 ^> for
the daily solar rotation, being the latitude. This is
deduced from spectroscopic measures in the regions of the
spectrum 4059 to 4126, and 4220 to 4277.

The solar activity is now definitely on the up grade, and
equatorial spots have died out, showing the demise of the
old cycle.

Mr. D'Esterre has continued his photographic and visual
patrol on selected regions of the Milky Way, and has dis-
covered many new faint variables. He had previously
stated that no known variable had a fainter minimum than
the eighteenth magnitude. He has now found four whose
minima lie between the eighteenth and the nineteenth
magnitude, and one that goes down to the twenty-first

The Transit Circle at Greenwich has been fitted with a
travelling-wire micrometer for observing transits. This
will make a minute alteration in Greenwich time, as the
" personal equation " of the old method will disappear.
It is found that all observers practically agree in their
observations on the travelling method. During a transit
the observer continually turns two handles, so as to keep
the star bisected by the travelling wire. Contacts are made
automatically- when the wire passes certain points in the
field.

BOTANY.

By Professor F. Cavers, D.Sc, F.L.S.

SEEDS OF W^TER PLANTS.— It has been stated by
different observers that the seeds oi some aquatic plants
do not germinate without first being dried ; others have
found that the passage of such seeds through the alimentary
canal of birds greatlv impn ives their power of germinating .
while it has been found that acids and alkalies arouse many
water-plant seeds from their dormancy. A closer investi-
gation of the peculiarities of the seeds of aquatic plants
has recently been made by (rocker and Davis Hot. Gazette,
Volume LVIII), who have dealt with the water plantain
{Alisrna plan/ago), but consider that their results probably
apply to water plants generally. They have studied in
this plant the structure and mien 'chemistry ol th<
coat, the water relations of seed and embryo, the eit
acids on the rate of intake of water by the embryo,
imbibition and growth elongation of the embryo, elasticity
of the seed-coat, and oxygen pressure in relation to the
germination of the seed and the formation of chlorophyll
in the seedling. They point out that delayed germination
(longevity) of seeds is secured in different way- in different
cases : by almost complete exclusion of water in the hard-
seeded Leguminosae and other seeds capable of remaining
dormant for very long periods: by limiting the degree of
swelling ol the embryo by surrounding structure.
Alisma, and probably other water plants; by reduction ol
oxygen supply below the minimum meessary (or germination,
as in various Compositae, some grasses, and soon, and perhaps
by deficiency of salt-. To these must be added delays due to
embryo characters, as slowness ol acid development in the
embryo of hawthorn, apple, and othei Rosaceae. All these
possibilities should be considered in Studying the mechanics
of delayed germination, instead of assuming, as some writers
have done, that injury to the seed-coat or the action of light
must act as a stimulus, and that dormancy i- therefore
determined bv the characters ot the embryo alone. In the
case of Alisma the authors conclude that dormancy i- due
to the mechanical restraint ol the seed-COEt, which enables
the seed to lie m water tor years without germination V
the intact achene in- m water m tin' saturated -tate the
embryo itself does not consummate more than one-fourth
of its possible iinbibition.il and osmotic -welling and in the

150

KNOWLEDGE.

May, 1915.

partially swollen state remains (or years in water restrained in
its swelling by the seed coat against which it exerts a pressure
of about one hundred atmospheres. When the seed-coat is
removed the embryo continues its swelling, which gradually
passes into growth enlargement. The pectic substances of
which the coat almost entirely consists are readily hydrolysed
by weak acids and bases, w Inch also change the water relations
oi these substances, as in the case of water-absorbing
colloids generally. Acids increase slightly the imbibitional
force of the embryo, while bases increase greatly the rate
ol elongation of the embryo. The effect of acids and bases
on the germination oi Alisma seeds is largely due to weaken-
ing of the seed-coat, so that the swelling embryo can break
away the coat-cap at the larger end of the seed. The
points of most obvious ecological importance are that the
seeds of Alisma, and probably those of water plants gener-
ally, are capable of lying in water for years in the imbibed
condition without losing their vitality, whereas those of
land plants can only withstand such storage for a short
time ; and that the embryo is capable, at the expense of
its stored food alone, of considerable growth in total absence
of oxygen, though it requires oxygen for development of
chlorophyll and a larger supply for branching and the
development of the primary root.

THE FLOWER OF PARNASSIA.— The flower of
Parnassia (Grass of Parnassus) shows, as is well known.
a remarkable peculiarity in the form of a series of five
candelabra-like structures, one within each of the five
petals, alternating with the five stamens. These structures
are regarded as sterile stamens (staminodes) : each has
a solid honey-secreting base, and each of the branches
into which it divides above this ends in a yellow knob,
glistening in the light and looking like a drop of honey,
though it is a solid body. Flies, deceived by this appearance,
have been seen licking the knobs. The genus Parnassia
has hitherto been placed in the Saxifrage family, though
the resemblance between its staminodes and the stamen-
bundles in the flower of St. John's Wort (Hypericum)
has led some writers to regard Parnassia as related rather
to the Hypericum family. For instance, in some species
of Hypericum each anther contains a gland, and, if the
pollen-sacs of these anthers were to become abortive, we
should be left with a bundle of filaments, each ending in
a gland, exactly like the staminodes of Parnassia. Mrs.
Arber (Annals of Botany, Volume XXVII) has investigated
the structure of the Parnassia flower in detail and has,
found that each stamen contains, in addition to the usual
single vascular bundle present in stamen filaments, distinct
traces of a number of other bundles in a reduced or vestigial
condition ; hence the fertile stamens agree with the
staminodes in showing several bundles, though in a vestigial
condition. She also finds that the bundles destined for the
stamens arise at a lower level in the receptacle than those
which go into the staminodes, confirming the view that
the staminodes represent the inner whorl of the androecium.
It is suggested that the peculiarities in the anatomy of the
stamens of Parnassia indicate that each individual stamen
is reduced from an ancestral stamen-bundle like that of
Hypericum, and that the two genera are closely related ;
also that Parnassia should be placed in a separate family
instead of being classed in the Saxifragaceae.

CHEMISTRY.

By C. Ainsworth Mitchell, B.A. (Oxon), F.I.C.

COLOURS OF FLOWERS AS INDICATORS.— An
interesting study of the behaviour of the colouring matters
of flowers towards acids and alkalies is published by Mr.
H. W. Brubaker in the Journal American Chemical Society
(1914, XXXVI, 1925). The petals of most flowers, especially
those of blue, red, pink, and purple tints, are changed in
colour by alkalies, while acids restore the original colour
or produce some shade of red. The yellow pigments, how-

ever, are unaffected by cither acids or alkalies, whereas
white flowers (white rose, pansy, clover, geranium) are
changed to yellow by alkalies, and back to white again
by acids. The reds and purples are turned to green or
greenish-blue by alkalies, while the original colour is
restored or intensified by acids.

As a rule, these colouring matters are of an acid character,
and are less frequently neutral. They appear to be closely
related to one another, and it would seem that the different
variations in the colour of a certain flower or species of
flowers are the results of slight chemical changes in the
original pigment.

So sensitive are some of these colouring matters to the
action of alkalies and acids that they can be used as chemical
indicators. For example, the red colouring matter of the
rugosa rose (Rosa rugosa) can be extracted with alcohol,
and the purified solution is turned green by alkalies, while
the red colour is restored by acids, and the liquid becomes
colourless at the point of neutrality. The indicator is
sensitive to carbonic acid, and changes colour in a solution
of sodium hydroxide, containing only one part in twenty-
five thousand. The colouring matters of the perennial
pea (Lathyrus latifolius), iris, and purple vetch behave
in an analogous manner, and appear to be either identical
with, or closely allied to, the pigment of the rugosa rose.

CHARACTER OF CREOSOTE IN PRESERVED
TIMBER. — Most of the preservatives for timber are com-
posed of a basis of creosote, to which is added tar or coloured
pigments to meet the popular taste. These preparations
differ greatly in their preservative action, and considerable
light is thrown on the causes of these differences by an
investigation of Mr. G. Alleman (Proc. Amcr. Wood Pre-
servers' Assoc, 1914, page 88).

The creosote oils extracted from well-preserved timber
that had been in use for several years were found to contain,
on the average, 32-9 per cent, of constituents boiling below
270° C. and 66-8 per cent, of constituents of high boiling-
point, ft is to a deficiency of the latter that the defects
of many modern creosote preservative must be attributed,
for the heavy constituents have much greater penetrative
and water-proofing capacity than the light oils.

As the result of the experiments the conclusion is drawn
that for general purposes at least fifty per cent, of the oil
should distil above 315° C, and for treating pavement
blocks not less than sixty-five per cent. The penetrating
power of tar is small, even when injected at a high temper-
ature, and when a mixture of tar and creosote oil is emploved
separation of the components may be observed towards the
margins of close-grained rings in the wood. In the case of
light creosote oils loss is inevitable owing to volatilisation,
extraction of the oil by rain, and crystallisation within the
wood. The preservative effect of creosote appears to depend
partly upon antiseptic action and partly upon the interior
cell walls of the wood becoming coated with a stable film
of the oil, which excludes moisture. Light oils are rich
in antiseptic substances ; but, as these are soluble in water,
they are soon washed out of the wood by the rain.

GEOGRAPHY.

By A. Scott, M.A., B.Sc.

INTERGLACIAL GORGES.— In those parts of the world
which show evidence of recent glaciation there is generally
considerable doubt as to the number of ice-invasions.
Such tests as the relative erosion of drift-materials of
different ages, or the amount of interglacial cutting by
streams whose profiles have been " de-graded " by ice-
action, are often difficult to apply. In the latter case,
the tributary streams may show several outlet gorges into
the main valley, which has passed through successive
stages of over-deepening. The number of gorges should
give the minimum number of interglacial periods, but not
the maximum, as there is nothing to hinder the re-excavation
of the old gorges. The width of the different gorges, con-

May, 1915.

KNOWLEDGE.

151

sidered in relation to the gradient and discharge of the
streams, should indicate the relative duration of the inter-
glacial periods.

Evidence of this nature has been obtained by Rich and
Filmer [Jour. Geol. January-February, 1915) in the case of
Six-mile Creek in New York State. Numerous moraines, a
typically glaciated cross-section, and a floor hanging 450 feet
above that of the main valley are certain evidence of the
intense glaciation this creek has undergone. In the valley-
bottom are three distinct gorges, two of them being pre-
glacial and the third postglacial. The earliest gorge is
clearly subsequent to the adoption of the U-shape by the
valley, but is apparently antecedent to two later glaciations.
Hence, it may belong to the first interglacial period. The
second gorge, cut in the floor of the first, is later than the
ice which filled the latter with drift, but the presence of
striae on the walls shows it to be earlier than the third
glaciation, so it belongs to the second interglacial period.
The third gorge is cut through the material deposited
during this last ice-invasion, and there is no evidence of
any subsequent ice-action. An alternative explanation is
the possibility of an origin by rejuvenation, but there is
no evidence of such a process in any of the adjacent streams.

TRANSPORTATION OF DEBRIS BY RUNNING
WATER. — An elaborate account, accompanied by diagrams
and tables of data, of numerous experiments on the trans-
portation of debris by running water is given by G. K.
Gilbert in one of the U.S. Geological Survey publications
(Prof. Paper 86). While a considerable amount is known
concerning the material carried in suspension by streams.
very few facts have been ascertained about the " bed-
load " or material swept along the river-bottom. In the
experiments described, specific loads of sand and gravel
are fed into artificial streams of known discharge, and
measurements taken of the effects of the various factors.
It is found that for each set of conditions there is a definite
gradient below which no load is transported, and that this
slope varies with the grain size of material. The variations
in the " capacity," i.e., power of transport, due to discharge
and grain size are of a lower order of magnitude than those
due to slope. The majority of the particles are transported
by a process of " saltation," or leaping, though the larger
ones show a tendency to roll. With small bed loads,
transportation takes place by the down-stream migra-
tion of mounds of material, very much like the advance of
sand-dunes under aeolian conditions. As the load increases,
the surface first becomes smooth, and then " antidunes "
form, with an up-stream migration of the crests. Numerous
formulae are deduced, but the application of these to actual
rivers must be made with extreme care, owing to the great
variation, with different conditions of load, discharge, and
so forth.

COMMERCE AMONG THE ESKIMO.- -In the past,
trade between the various Eskimo tribes has been con-
ditioned by the feasibility of the routes and the resources
and distribution of the tribes. The chief highway is the
sea, not, however, as water, but as ice. The short season
when there is open water is entirely taken up by harvesting
and hunting, so that trading is relegated to winter and
spring. Until recently, sled journeys from Alaska, even
to the Siberian side of the Behring Sea, were common. The
chief trading route between the Mackenzie Delta and Hudson
Bay lies along the coast as far as (ape Parry, turns north-
ward to Nelson Head, and then eastward through Prince
Albert Sound, and across Victoria Island. From there it
runs due south for three hundred miles to the head of
Chesterfield Inlet, and finally down the latter to Hudson
Bay. Another route, now disused, keej the coast

of the mainland, and passes through Coronation Gulf.
The speed of such a journey may be judged from the fact
that the minimum time necessary for an article from
Alaska to reach Hudson Bay is two and a hall years, while
the average time is probably nearer five years. The
Behring communities transport Siberian goods, such as

ivory, blubber, and oil. eastward and receive in return
skins and stoneware. A full account of the articles which
the various tribes deal in is given by Stefansson (Can. Geol.
Survey, Museum Bulletin So. 6), and the dependence of
these on resources, routes, and so on, is discussed at some
length.

GEOLOGY.

By G. W. Tyrrell, A.R.C.Sc, F.G.S.

ORIGIN OF CHINA CLAY.— The origin of this import-
ant economic product is dealt with in considerable detail
in a Handbook to the Collection of Kaolin, China Clay, and
China Stone in the Museum of Practical Geology, written
by Dr. J. A. Howe, and published by the Geological Survey.
The great West of England occurrences are fully described,
along with the methods of obtaining the clay and preparing
it for use. Other occurrences at home and abroad are next
described. This is followed by chapters dealing with china
stone, the uses of china clay and china stone, the mineral
kaolinite and its allies, and the various theories of origin
that have been propounded from time to time. The last
two chapters contain statistics of production and a list of
the china clay works of the West of England. An excellent
appendix by Mr Allan Dick describes the microscopical
characters of kaolin and the delicate methods of investi-
gation used for this and similar substances. The hand-
book runs to 271 pages, and is an excellent and most interest-
ing production

The principal hypotheses put forward to account for the
production of kaolin (mainly from felspars and felspathic
rocks) are based on the action of the following agencies :
(1) Surface weathering ; (2) waters descending from swamps
and bogs ; (3) ascending waters containing carbon dioxide ;
(4) emanations following igneous activity ; (5) sulphuric-
acid solutions and hydrogen sulphide ; (6) hydro]-.

The question of origin is of especial interest in con-
nection with the rich deposits of the West of England. These
arc associated with the great gTanite intrusions of that area
especially those of St Austell, Bodmin Moor, and Dartmoor
The hypothesis that surface weathering is the chief agent
of kaolinisation is the oldest, and still holds pride of place
in the textbooks ; but there are niMiperable objections to it

in the c.ise of the West of England deposits. It is difficult
to explain the extremely local distribution "t the kaolin
on this hypothesis. One would expect it to be a common
and widespread superficial deposit in most granites it it
were due to surface weathering. Moreover, gramt
quently weathers to considerable depths, but with the
formation of materia] very different from china clay The
theory which ascribes the origin of the West of England
i hin. i clay to the heated gases and liquids accompanying
or following igneous intrusion (pneumatolysisi finds much
support from the observed facts The localised occurrence
oi the kaolin and the fact that the kaolin Ixnhcs appear to
become more extensive downwards find ready explanation
on this theory Moreover, the kaolin is frequently
ciated with topaz, fiuorite, and cassiterite — minerals which
are known to have been formed by emanation- containing
boric and hydrofluoric a< ids Dr Howe shows that it does
not necessarily follow that kaolin is due to the acti
these particular ... id- on the lel-pars of the granite, but
he. nevertheless, accepts the view that kaolin is due to some
kind oi pneumatolytic action, and i- inclined to considei
that carbon dioxide, always an important emanation
product, i- tin' chief agent in the process. He points out
that the operation of tin- factor is not excluded in any ot
the described occurrences of kaohn, and is accepted b\
exponents ot all theories alike. It- activity i- recognised
in the later phases oi pneumatolysis, in ordinar) weathering
and the action of peaty water- in the action of hot or
i old spring intaining tin- gas, and also in the process

ot hydrolysis.

is:

KNOWLEDGE.

May, 1915.

METEOROLOGY.

Bj Wmii \m Marriott, l-.R Mi r.Soi

III1-: WEATHER OF MAY.— The month oi May is

gem-rally characterised by a great increase ol warmth and
sunshine, while the still increasing power of the Sim's rays

tnifests itselt by the rapid advance oi vegetation. May
is, however, subject to groat vicissitudes of temperature,
and sometimes sharp frosts occur at night, which seriously
injure the fruit and cereal crops.

•• Till May be out
Leave not off a clout.''

.Ma\ was a vcrj cold month in the years 1845, 1855,
1856, 1877, 1879, 1885, and 1902 ; and it was very warm in
the years 1841, 1848, 1865, 1868, 1893. and 1895

The average mean temperature at Greenwich for May

is 53 -0 ; in 1S4S it was as high as 59° -7, while in 1879 it
was as low as 48° -6. The average maximum temperature
is 63°-9; the highest mean was 73° -3 in 1848, and the
lowest 57 -3 111 1902. The average minimum temperature
i- -13 -7; the highest mean was 48° -3 in 1841, and the
lowest 39 -2 m 1876. The absolute highest temperature
recorded was 87 -5 in 1880 on the 26th, and the absolute
lowest was 28°-l in 1877 on the 4th. The latest date on
which a temperature below 32° was registered was on
the 24th in I8H7.

The average rainfall for the month of May is 1 -95 inches ;
the greatest amount was 4-37 inches in 1865, and the least
0-25 inch in 1833. The heaviest fall in one day was 1-40
inches in 1825 on the 13th. The average number of " rain
■ lays " (i.e., on which 0-01 inch fell) is 12-4 : the greatest
number of days was twenty-two in 1902, and the least
three in 1848. The average amount of bright sunshine at
the Kew Observatory, Richmond, is two hundred hours.

The average barometric pressure in London for May is
29-969 inches ; the highest mean was 30-227 inches in 1896,
and the lowest mean was 29-790 inches in 1891.

CYCLONES AND ANTICYCLONES.— It will be remem-
bered that it was proposed to hold a Meteorological
O inference in Edinburgh in September last, but owing to the
war it had to be postponed. Two or three papers which were
to have been read at the Conference have now been printed
in The Journal of the Scottish Meteorological Society. One
of these, on " Cyclones and Anticyclones." is by Mr. W. H.
Dines, F.R.S., and in this he points out that the old convec-
tional theory of the cyclone, known as " Ferrel's Theory,"
is utterly untenable in view of recent knowledge.
Observations obtained by means of registering balloons
have led to the definite conclusion that the lower strata of
the atmosphere are relatively cold in cyclones and relativelv
warm in anticyclones. The statistical treatment of the
observations has led to certain other conclusions, and shows
that there is a very intimate connection between the
temperature and the pressure of the upper air, but that,
except close to the surface, there is very little connection
between the temperature of the air and its direction or rate
of motion. The importance of the pressure at a height of
about nine kilometres is demonstrated, and an explanation
is given of the way in which the temperature conditions in
cyclones and anticyclones follow naturally from the dis-
tribution of pressure of nine kilometres. Mr. Dines further
points out that the effect of radiation is of secondary import-
ance in altering the temperature of the air.

TORNADO IN WALES, OCTOBER 27th, 1913.

Reference was made in " Knowledge " (Volume XXXVI,
page 465) to the remarkable storm of a tornado type which
occurred in South Wales on October 27th, 1913. The
Meteorological Office has published, in The Geophysical
Memoirs, a report on this tornado by Mr. H. Billett who
spent three days in visiting the greater part of the region
affected by the storm. A system of violent meteorological
phenomena passed along a line running almost due north
from the south of Devon to Cheshire, between 3.45 and

9 p.m. There appear to have been four main regions of
ai lion in its path, namely, (1) South Devon, (2) South
Wales, (3) Shropshire, and (4) Cheshire ; the most violent
was that in the Tall \ alley. One of the most remarkable
features of the storm was the sharpness of its boundaries
on either side of its track. Practically no damage was done
outside the narrow limits of the course, which nowhere
exceeded one thousand feet in width. The tornado was
accompanied by very severe lightning and torrential rain-
fall, and reached its greatest force at Abercynon and
Edwardsville, where five deaths occurred. The storm was
circular in shape ; and, as it progressed with a speed of
thirty-six miles per hour, its duration at any place, assuming
the width of the track within which damage was done to be
three hundred yards, works out at seventeen seconds. The
evidence collected shows that the storm was a genuine
tornado of the type common enough in parts of America,
but fortunately of rare occurrence in this country.

MIRAGE ON THE CORNISH COAST.— Mr. P. H.
Horton in a letter to The Times gave a graphic account of
a curious phenomenon which he saw from the Cornish coast
at Mawnan, a few miles from Falmouth, for about half an
hour on the afternoon of October 24th. In a shallow cloud-
bank, stretching across the horizon from south-east to
south, there gradually appeared what seemed to be a line
of coast, with woods, trees, fields, hedges, and houses in
their natural colours. At first he thought it was merely
a peculiar arrangement of clouds, but soon he recognised
that it was a complete reflected panorama of the coast,
and he gradually identified St. Keverne, with its church
spire, the Helford River, Mawnan Church, Rosemullion,
Falmouth Harbour, and St. Anthony. Shortly before the
whole scene faded away a reflection of Pendennis Head, with
the Castle and the military huts, emerging like some huge
ship from a fog bank, appeared most distinctly, and was
visible for several minutes. Every detail of the whole
scene was reversed as in a looking-glass, and slightly
magnified ; for, although the panorama seemed to be some
twenty miles away, everything appeared as it would to an
observer from the distance of only a mile or so. The colours
were a little less bright than those of the real coast at the
time. Mr. Horton adds that the scene, as a whole, was
visible all the time, but the details of a small portion only
were quite distinct at any one time, commencing in the
south and gradually moving towards the east, the effect
being that of a powerful searchlight being very slowly
turned from right to left on to the opposite shore of a large
lake.

MICROSCOPY.

By F.R.M.S.

NEW METHOD OF STAINING RADULAE.— Figure
126 on page 147 shows the radula of Zonites olivetorum of
Moquin-Tandon.of which I took several specimens in August,
1897, near the top of the Col de 'fillet (Hautes- Pyrenees). We
have no British form with a radula of this type, but it may
be compared to Politti nitidula. The figure is introduced
here in order to show the advantage gained by staining
the radula with a suitable stain and mounting in Canada
balsam, the refractive index of which is nearly the same as
that of the chitin of the radula, while it is also in corre-
spondence with the optical system of the microscope. Thus
the picture seen on the stage is entirely due to the stain,
and contains no fallacious shadows representing difference
of refractive indices. The resolution in depth is the maxi-
mum possible without distortion of the elements of the
picture. The photograph was taken with an objective of
N.A. 0-18, and the structures are large.

The method adopted is as follows : —

(1) Boil out the radula with one or two per cent,
caustic potash, wash, and neutralise with dilute
acetic acid.

May. 1915.

KNOWLEDGE.

153

(2) Arrange the radula on the slide, after clearing away

the adherent membranes, i.e., the lining of the
odontophore sac.

(3) Cover the radula with a drop of acidified perman-

ganate solution. The best formula for use will
vary with circumstances, but that employed
in the making of autochromes serves very well.
The unci- — and, to some extent, the whole
membrane — are now seen to turn vellow, brown,
and, finally, black.

(4) Now wash off the permanganate, which has ful-

filled its oxidising function, with distilled water.

(5) Cover the radula with a drop of oxalic-acid solution,

which will gradually decolorise it, with evo-
lution of C0 2 .

(6) Wash thoroughly with distilled water and again

soak in dilute acetic acid.

(7) The radula can now be stained in a weak solution

of dahlia in one per cent, acetic acid. The
advantage of using a weak solution is that the
progress of staining can be watched ; but over-
staining does not very readily occur, because
the oxidation is limited to the external layers
of the chitin, and thus a transparent effect can
be obtained.

(8) Dehydrate, clear in oil of cloves, and mount in

xylol balsam.
Though this process seems long, it is, in reality, quite
simple and easy, and the effect can be seen at each stage,
so that there need be no doubt about the final result if the
operations are conducted with reasonable care. Such a
preparation may be regarded as permanent : it requires no
ringing. Some other stains can be used in place of dahlia,
but I have not yet found any equally satisfactory. The
object looks bluish-violet by daylight and violet-red bv
lamplight. It is easily photographed on the Ilford chro-
matic plate with a yellow or green screen. Personally I
prefer the latter, as giving a little more contrast. The full
aperture of the objective (if it is of a good make) can be
used.

Hydrolysis of the chitin also may be brought about by
various reagents, and renders the radula permeable to many
stains, such as acid fuchsin, indigo carmine, and brilliant
black. The various methods of inducing hydrolysis which
I have tried have, however, been much more uncertain and
tedious than the superficial oxidation process described
above. E. W. Bowell.

THE PHOTOMICROGRAPHIC SOCIETY.— In the
year 1911 the Photomicrographic Society was started,
and since that time it has been actively at work. The
ordinary meetings are held at King's College Bacteriological
Laboratories, 62, Chandos Street, London, W.C, at 8 p.m.
on the second Wednesday in the month, from October to
May inclusive. At these gatherings visitors are welcomed.
There are, besides, " members' evenings " — usually on the
fourth Wednesdayin the month — for membersonly. Hitherto
the proceedings of the Society have been issued, but they
have not been printed. Now we are able to welcome them in
ty-pe as The Journal of the Photomicrographic Society (price
to non-members, 3s. 9d.). The present instalment contains
an account of several ordinary meetings, and the papers
read at them, including one by Mr. J. E. Barnard, on
" Colour Screens." This should be of particular use to
those who are photographing through the microscope,
as it is most practical. The absorption spectra of some of
the filters are given as plates. There is also a paper, bv Mr.
Martin Duncan, on " Studies in Marine Biology," and one,
by Mr. C. A. Bunnin, on " Colour Sensitive Plates and their
Uses." Beginners in the work will find Mr Wellesley
Harris's " Hints on Photomicrography " most helpful.
The success which Mr. Wellesley- Harris obtains with the
methods which he uses and describes can be gathered from
the illustrations, which we have been kindly permitted to
reproduce on page 148, and as in his paper he gives very
full details as to lighting, lenses, camera extension, and so on,

he makes it all the easier for those who take up photo-
micrography to follow in his footsteps. We might add that
the subscription to the Society is seven shillings and sixpence
for the session, and includes two issues of the Society's
Journal. The Honorary Secretary is Mr. J. E. Bradbury,
1. Hogarth Hill, Hendon, X \Y. W. M W.

HAIRS OF THE LARVA OF AX AXTHREXUS —
On unpacking a small consignment of insects from Xatal
I found amongst them the living larva of a coleopterous
insect, probably that of an Anthrenus. Shortly afterwards
it entered the pupa state, and in due course a small beetle
about one-ninth of an inch long was developed. The

a

a x 50.

310.

d x 310.

c ■ 50.

Figure 131.

thorax and elytra of this were covered with beautiful
scales, white, dark brown, and orange-coloured, arranged
in symmetrical patterns. Having mounted the exuvium
in Canada balsam, I found, on careful examination, a
considerable difference between it and that of the species
only too well known to insect collectors in this country.
The body in each case was covered with delicate pointed
hairs, the majority of which were fringed throughout
their entire length by minute secondary hairs see Figure
131c), but from the margin of each segment, except the
first and last, in the Xatal species there extended a large
number of spear-headed hairs (see Figure 1316), somewhat
similar to those which used to be mounted and sold under
the name of " Hairs of the larva of Dermestes,'' although
it is well known to entomologists that the genus Dermestes
does not possess them. In the English variety these hairs
(see Figure 131 d) were only to be found near the tail A com-
parison between them showed that those of the former were
smaller, and that the whorls with which the shafts were
adorned were closer together and less prominent, whilst
the heads of the spears differed in shape at their bases, and
were proportionately longer, though not quite so broad Two
dense tufts, each consisting of not fewer than two hundred
hairs, proceeded from the lateral margins of the last segment
but one, and extended much beyond the last segment itself
The feet in each case carried a single claw, but those of the
English species (see Figure 131«) were larger and st:
than those from Natal (see Figure 131a) ; the mandibles
in each case were simil.it in size and shape. A still smaller
beetle from China, obviously an Anthienus. is a
with black scales of the fame shape as those of the
species. R- T. L.

THE QUEKETT MICROSCOPR VL CLUB.— At the
five hundred and sixth ordinary meeting of the Club on
Tuesday, March 23rd, Mr r D Soar r.-.id a risumi of a
paper by Mr. Williamson and himself on " British Hydra-
carina, genus Lebertia" Mr J W Cordon showed and

154

KNOWLEDGE.

May, 1915.

described an objective thai bad been made for him by Messrs.
Beck in 1909. It is a half-inch dry lens, fitted with a front
Carrying an oil-immersion lens. It was described in the
catalogue oi the Optical Convention in 1912. Its properties
and advantages were explained. They resembled those
obtained with high-power immersion lenses, and which
had previously been considered to be obtainable Only with
powers of one-eighth inch or one-twelfth inch.

\ paper In Mr. Harris on "Microscopical Methods in
Brvological Work " was read by Mr. F. j. Perks. It dis-
cussed various media suitable for mounting mosses, with
the methods that should be employed in order to display
the structure as well as the whole plant.

For tickets of admission to the meetings, application
should be made to the Honorary Secretary, Mr. James
Burton, S, Somali Road, West Hampstead, N.W., or to any
of the leading London opticians.

J B.

PHOTOGRAPHY.

By Edgar Senior.

MAKING NEGATIVES READY FOR PRINTING—
Apart from retouching, a great deal can be done to improve
the printing qualities of a negative by the expenditure of
a little time upon each one. After drying. — which operation
should be carried out as far as possible in an even tempera-
ture, and should not occupy more than three or four hours —
the negative should be examined carefully for any defects,
such as pinholes, air bells, scratches, and so on, and these
should be carefully touched out by means of a fine sable
brush and water colour. Almost any pigment which will
not allow the chemical rays to be transmitted will answer
the purpose ; thus Indian red or carmine have both been
largely employed, as well as a specially prepared substance
known as " Gihon's opaque." A common mistake with
beginners when spotting is that they use the colour too
thin, when, in the case of a transparent spot, the colour
runs round the hole, and leaves the centre bare, and this has
afterwards to be filled in. The trouble may also arise from
the use of too large a brush. The colour must not only be
used as dry as possible, but should be applied with a very
small sable brush, such as a § of Newman, or a series 15 of
Winsor & Newton — camel-hair is useless. Pinholes can,
as a rule, be spotted out by a single touch, whereas large
spots, such as those due to air-bells, require to be filled in
by means of a succession of small touches, applied in such
a manner as to bring the density up as nearly as possible
to that of the surrounding parts of the image. Scratches
on the film, if only surface-formed, can very often be obli-
terated by means of a finely pointed pencil. When the sky
in the negative of a landscape or architectural subject
is defective, it is often better to block it out completely.
This may be accomplished as follows. Make a rough print
from the negative on P.O. P. paper, and cut out the sky
portion at a distance of about one-sixteenth of an inch
above the outline of the landscape portion. The sky of
print is then exposed to daylight to blacken, and while this
is taking place the outline of the sky on the negative is
blocked out for about a quarter of an in / "h all along. The
sky portion of the print having become blackened is now-
used as a mask by attaching it to the negative — on the film
side — by means of a few touches of gum. The slight amount
of trouble taken in painting out round the outline of the
landscape is more than compensated for in allowing the
sky mask to be more or less roughly cut out ; and, besides,
no matter how accurately this may have been cut, it is not
easy to fit it to the negative when the outline cf the subject
is at all intricate. In the case c f architectural or other
subjects in which there may be a series of straight lines,
it is often found very difficult to outline these with a brush
without producing the appearance of a broken or wavy line.
A better plan would be to use a drawing-pen and a straight-
edge, and charging the pen with Indian ink, to hold it ver-

tical or at right angles to the negative, and without bearing
too heavily upon it, proceed to draw a good thick line along
those parts of the building having straight lines standing
out against the sky, and then, afterwards, with the brush
proceed to fill in any little corners where the drawing pen
could not be used. Having outlined the whole, the entire
surface of the sky may now be gone over with the brush,
bringing it just to touch the lines made by the drawing-pen,
by this means completing the blocking-out of the sky or
background.

EMPLOYING USED FERROUS OXALATE DE-
VELOPER. — It may be of interest to some to know that
ferrous oxalate developer that has been used, instead of
being thrown away, may be employed to provide potassio-
ferric oxalate, this substance being the basis of one of the
best reducers, which is known as " Belitski's reducer."
All that is necessary is to place the used developer in a dish,
so that it is freely exposed to the air, when the emerald-
green crystals that are deposited are collected and rinsed in
cold water, to free them from any oxide of iron which may
adhere to them. This being done, the crystals are dried on
filter paper, and placed in a well-stoppered bottle, and kept
in the dark, as potassio-ferric oxalate is somewhat sensitive
to light. In order to prepare the reducing solution, thirty
grains of the salt are dissolved in half an ounce of water, and
then mixed with half an ounce of the fixing bath containing
four ounces of " hypo " dissolved in twenty ounces of water.
The negative which requires reducing is placed in the
solution contained in a dish, which is kept rocked during the
operation. Reduction soon commences, and proceeds
regularly, and when finished is followed by a thorough
washing under a stream of water, which completes the
operation. When done with, the solution is thrown away,
as the mixed solutions do not keep,

PHYSICS.

By J. H. Vincent, M.A., D.Sc, A.R.C.Sc.

DETERMINATION OF TEMPERATURE BY
MEASURING RADIATION.— The temperature of a
source of radiant heat, such as the interior of a furnace,
may be deduced from observations on the radiations which
it gives out. If one assumes that the interior of the furnace
behaves as an ideal black body, as will be the case if the
observation is carried out through a small break in the
enclosure to the furnace, then by Stefan's law the total
radiation is proportional to the fourth power of the absolute
temperature. The radiation can be concentrated on to
the surface of some form of bolometer, or on to a thermopile,
by means of a mirror or lens ; and the instrument can be
calibrated by the use of sources of known temperature.
The Fery radiation pyrometer is an instrument of this class.
It consists of a reflecting telescope, which is pointed at the
interior of the furnace through a hole in the wall. After
reflection from the face of the concave mirror the radiation
falls on a thermo-couple placed at the conjugate focus
to the hole in the furnace wall, and thus situated between
the face of the mirror and the hole. On the other side of
the mirror is an eyepiece by means of which the observer
looks through an aperture in the centre of the mirror, and
adjusts the image of the opening in the furnace until it
slightly overlaps the disc which forms the absorbing surface
of the thermo-couple. A suitable galvanometer is connected
in series with the thermo-couple, and its deflections are
proportional to the fourth power of the absolute temper-
ature of the source.

OPTICAL PYROMETERS.— These instruments, of which
several forms are in use, all have a photometric basis.
They compare the intensity of the red rays from the source
with the intensity of the red rays given by a standard lamp.
For example, in the Holborn-Kurlbaum pyrometer the
filament of an electric glow-lamp is placed in the focus of
the telescope which views the source. The current through

May, 1915.

KNOWLEDGE.

155

the filament is then adjusted until the filament is of the same
intensity as the source. It is now assumed that the tem-
peratures of the source and filament are the same, and in
order to standardise the instrument it is necessary to find
the connection between the current through the filament
and its temperature. This may be done by using several
standard temperatures in an experimental furnace, the
standards being the known melting-points of various pure
substances. On the other hand, one could calibrate the
instrument from observations on a suitably constructed air-
thermometer, the bulb of which is placed in the experimental
furnace.

It will be noticed that with total radiation pyrometers and
with optical pyrometers the observations are taken on the
interiors of enclosures, the walls of which are at practically
the same temperature throughout. If such instruments
are directed on to the glowing surface of a crucible of molten
metal freely exposed to the laboratory, the reading for the
temperature would be too low, because the radiating surface
is not black, nor does it behave as black, in a radiation sense,
unless it is totally enclosed in opaque walls at the same
temperature.

A NEW PRINCIPLE IN OPTICAL PYROMETRY.—

Paterson and Dudding recently read a paper entitled " The
Estimation of High Temperatures by the Method of Colour
Identity " before the Physical Society of London. In this
paper the authors introduce an entirely new principle into
optical pyrometry. Their method of temperature measure-
ment is based on the physical discovery- that, when a body
is radiating in the open, and not in an enclosure at a uniform
temperature, the colour of the light emitted (in the visible
spectrum) may be identical with the colour emitted by a
black body, even though the total radiation over the visible
spectrum is less than that due to a black body. Such
sources of light may be appropriately termed " grey," and
Paterson and Dudding's method may be summarised by
stating that the temperatures of " grey " bodies are identical
with those of black bodies when the tint of the light is the
same.

The comparison of colour is made similarly to photo-
metric comparisons of intensity. In the practice of the
method the intensity adjustment is also carried out, al-
though no readings of the photometer bench are taken.
The readings actually recorded are the values of the current
in the comparison glow lamp. In order to convert these
readings into temperatures it is necessary to find the
temperatures of the filament by other means, as in the case
of the Holborn-Kurlbaum pyrometer.

THE AEOLIAN HARP.— This instrument offers several
interesting problems, which have not, up to the present,
been completely solved. In general appearance it resembles
the monochord of the instrument-maker, and consists of
a sound box, 3-ft. long, 5-in. wide, and 3-in. deep, made
of pine, with hardwood ends to hold the tuning pins and
hitch pins. A dozen or so of gut strings of different thick-
nesses, stretched rather slackly over the bridges near each end
of the sounding-board, are tuned in unison. The sounding-
board is provided with two rose holes, like those of a violin.
A long funnel is formed of an upper board, which rests an inch
or two over the strings on projections from the hardwood
ends, and of an extension laterally of the sounding-board.
The harp is placed on the window-sill, and the lower sash
drawn down on to the top of the funnel. With moderate
wind the sounds are pleasing, but when the wind i too
violent, shrill discords result.

Rayleigh has already dealt with the subject, and now
returns to it in a paper entitled " Aeolian Tones" m The
Philosophical Magazine for April. 1915. He has shown that
the vibrations of the strings are transverse to the wind, and
has subjected the matter to mathematical analysis Some
of the results have been further tested by experiments on
motion in air and by observations on a pendulum suspended
in moving water.

RADIO-ACTIVITY.

By Alexander Fleck, B.Sc.

ANNUAL REPORT OF THE RADIUM INSTITUTE
— The report of the work accomplished by this institute
during 1914 has just been published. The first few pages
are devoted to a description of the form in which the radium
is used, the screens with which it is covered, and the length
of time during which the active material should be applied.
A short account is also given of the results that should be
looked for by different exposures to the rays, and the various
factors which influence these results are also stated. The
greater part of the report is, however, occupied in enumer-
ating the various diseases which have been treated, and
discussing the results obtained, with a detailed description
of a large number of typical cases. The report concludes
with a short account of the work of the chemico-physical
laboratory of the Institute, which shows that its work is
extending rapidly, and in many instances the requirements
during 1914 have been three or four times as great as those
of 1913.

Although the record of 1914 does not disclose any epoch-
making results in the treatment and cure of malignant
disease, it can at least be said that steady progress is being
made in the better use and control of the energy and pro-
perties of radium.

A NEW METHOD OF RADIUM THERAPY— A
number of papers by Dr. W. C. Stevenson, of Dublin, have
appeared during the past months in various medical
journals describing one method which has been used in that
city for the medical use of radium emanation. The essen-
tially new feature of this method is that the radium
emanation is sealed into capillary tubes of 0-76 millimetre
external diameter. These tubes are then fixed with wax
inside hollow needles of one millimetre external diameter,
which are very similar to the needles of a hypodermic
syringe. The great advantage of them is that they can be
insetted into a tumour with comparatively little pain to the
patient, and without the use of an anaesthetic. As fifty
millecuries of emanation can be placed in one inch of the
capillary tube, and as six needles can be inserted in one
moderately sized tumour, it is evident that the dosage of
radium can be varied at will over a large range. There is
also the additional advantage that the whole of any desired
region can be radiated much more uniformly than is possible
with one supply placed at one point.

THORIUM CONTENT OF THE EARTHS CRUST.

A paper is contributed by J. H. Poole to the April number

of The Philosophical Magazine on this subject. It gives the
results of the analysis (by radio-active methods) of the
thorium content of a large number of acid, intermediate,
and basic igneous rocks. The method employed is a com-
parative one, described by Joly a number of years ago, in
which the activity of the short-lived emanation is measured.
The results of the work are (1) The more acid an igneous
rock is, the more thorium it is likely to contain [2 the
average content of a gramme of granite is 2 ;
grammes of thorium, and of a gramme of
0-56 x 10- 5 grammes of thorium; (3) the mean value of
the thorium content of the earth's crust is probably
mimes per gramme . and ■ is no

constant relation between the amount- oil radium and
thorium in igneous rocks, and consequently there is no
evidence, so far as this work goes, of a genetic com.
between thorium and radium.

ZOOLOGY.

By Professor J. Arthur Thomson. M a , LLP

\N ISHMAELITE IBEX.— Dr. John C Phillips reports
on the Sinai Ibex [Copra >.-:< much per-

secuted species, which is found over all the ragged parts of

15fi

KNOWLEDGE.

May, 1915.

the Sinai Peninsula. " K very hand is against it during the
entire year, and its freshly dropped kids are eagerly hunted
by the natives with dogs." Its numbers are dwindling,
but it still persists. Caves among the rocks are used as
hiding-places. It seems to be independent of water — at
least during winter and spring.

LONG -CONTINUED PARTHENOGENESIS. — Dr.
A. M. Banta, working at the Cold Spring Harbour for
Experimental Evolution, has reared a hundred partheno-
genetic generations of Daphnia pulex, the common water-
flea. There was no occurrence of males, and no evidence
of decreased vigour or loss of vitality in the lines. Hence
it appears that there is no necessary sexual cycle in the
reproduction of this crustacean.

A POWERFUL TOXIN.— A mould growing on bread
does not suggest an extreme of poisonousness, but that is
what R. A. Gortner and A. F. Blakeslee have found to be
true of Rhizopus nigricans, which produces a deadly toxin.
The toxin has no effect when taken into the food canal
by a rabbit, but it is fatal if injected into the veins, even in
so small an amount as 1 to 275,000 parts of body weight.
It is one of the most poisonous organic substances known.

GASTROLITH FROM A MOOSE.— It is not uncommon
to find concretions in the stomach of herbivorous animals,
the " hair-balls " of horses and cows being very well known.
Professor D. Fraser Harris describes an interesting form
from the Moose, which consisted of concentric layers of
calcium phosphate around a flat, smooth piece of slate.
The whole was a hard oval calculus, about two inches in
length. Similar concretions have been reported with a
tooth in the centre.

PREDICTION OF SEX.— It would be difficult to find
a problem in regard to which there has been, and still is,
quainter speculation than that of the determination of
sex. There is a widespread theory in Japan that the dis-
position of the hairs on an infant's neck affords a basis for
predicting the sex of the next child, if there is one. If the
lines of hairs from the neck to the occipital region are
divergent, the next child will be a boy ; if the lines converge,
a girl. Mawe and Perriraz have been recently inquiring
whether this holds for Europe.

A ZOOLOGIST AT THE FRONT.— Corporal Fred Vies, a
zoologist well known for his interest in the problems of animal
locomotion and for his beautiful cinematograph films of
sea-urchin development, made an interesting observation
on a road somewhere near the Aisne. He was bicycling
slowly on a day without wind, and observed a wasp flying
backwards in front of him. That is to say, the tip of the
abdomen was foremost in the progression, and the head faced
the observer. The wasp was attracted by traces of fruit
on M. Yles's cap, and kept up the backward flight for more
than ten yards at a time. As the observer points out, the
case well deserves further investigation.

NUMBER OF BRITISH BIRDS.— The British Ornitho-
logists' Union has brought out a second and revised edition
of their well-known " List of British Birds." It includes
no fewer than 475 names. 99 more than there were in the
first edition (1883). An appendix gives a long list of birds,
whose claims to be called British have been rejected by the
Editorial Committee. Of the authenticated list of 475,
18S are regular breeding birds, 286 are non-breeding, and
one (the Great Auk) is extinct. There are 141 residents,
47 summer visitors, 46 winter visitors, 30 birds of passage,
61 occasional visitors (recorded more than twenty times),
and 149 rare visitors (recorded on fewer than twenty occa-
sions). That the last should be the largest category in the
classification shows how diligent the search for the occurrence
of rare birds has been in the British Islands.

DETERMINATION OF SEX IN PIGEONS.— Very
interesting observations have been made by Dr. Oscar
Riddle, who finds evidence of two different kinds of eggs in

pigeons. Those destined to produce males are smaller,
and have higher water-content and smaller energy-content
than those that will produce females, By means of the
bomb calorimeter he has been able to demonstrate that eggs
destined to become males contain less stored energy than
eggs destined to develop into females. We are referring to
a preliminary notice of Dr. Kiddle's work, and we presume
that the account of his observations will explain how it is
known that an egg is destined to become a male or a female
until it docs. We note however, that the investigator is
quite clear that tin- difference in energy-content may be
an effect of sex-determination, and not the cause.

BLIND TACTICS. — How can one explain the well-
known fact that many an insect-mother is careful to secure
the welfare of her offspring which she never sees ? She
lays her eggs in appropriate places, often very difficult to
get at ; she surrounds them with food-materials ; she often
collects a living larder of paralysed creatures to satisfy
their juvenile appetite. Vet she is dead and gone before
her offspring are hatched ! There is no doubt that we have
here to deal with one of the greater problems of biology,
and one that has not been seriously tackled. How can
a creature work sedulously, intricately, persistently towards
an end which is unknown, which cannot be pictured, because
never experienced ? We would, in the meantime, suggest
that part of the puzzle may disappear if we assume that the
ancestors of the insects in question did survive to see their
offspring. It may be that the routine now instinctive. —
that is to say, hereditarily entailed — was established among
ancestral forms that did survive to see the reward of their
labours. The dim meaningfulness of to-day may be an
echo of a clearer significance in ages long since past.

LONG PEDIGREE OF SLIPPER ANIMALCULES
MULTIPLYING ASEXUALLY.— We have already re-
ferred in these Notes to the continuous generations of
Paramecium aurelia which have been observed in the Yale
Zoological Laboratory by Professor L. L. Woodruff. In
November, 1914, the race had existed for seven years and
four thousand five hundred generations, and remained
quite normal, though there is no conjugation. In a study by
Woodruff and Rhoda Erdmann attention is directed to
a very interesting occurrence which they call "endomixis."
At frequent intervals the old nuclear apparatus breaks down,
as if conjugation were going to occur, and a reorganisation
is effected, which initiates a period of new metabolic activity,
and therefore of reproductive activity. It occurs on an
average about once a month. It may afford a field for the
origin of variations. It is an internal regulatory pheno-
menon which is self-sufficient for the indefinite life of the
race in a favourable environment. This is obviously an
idea of great interest.

MEMORY OF COCKROACH.— Dr. F. Bretschneider
kept Cockroaches in a breeding-cage, and fed them in
an adjoining experimental cage, the communication between
the two being through an aperture which could be closed.
The feeding-cage had a glass floor, which was cleaned every
day, and the cage was divided into two chambers by a
partition with six apertures, which could be closed and
opened. The food was placed in the chambers farthest
from the dwelling-cage. A lateral opening in the partition-
wall was opened to begin with, and the insects got accus-
tomed to use it. After a time it was closed, and one at the
other side was opened. But the insects continued to try
the closed door, which shows a local memory. There could
be no scent, as the glass floor was washed every day.
Szymanski showed in 1912 that Cockroaches could be taught
to prefer the light half of a cage to the dark half, which is
contrary to their nature, by arranging that those who went
into the dark half got a mild electric shock. They soon
learnt and soon forgot again, but they took a shorter time
to learn the second time. The seat of memo r ' is almost
certainly in the mushroom-shaped bodies on i anterior
surface of the protocerebrum.

THE FACE OF THE SKY FOR JUNE.

By A. C. D. CROMMELIN, B.A., D.Sc, F.R.A.S.

Table 25.

Sun.

Moon.

Mercury.

Venus.

Mars.

Jupiter.

L'ranus.

Nept

une.

Date.

R.A. Dec.

R.A. Dec.

R.A. Dec.

R.A.

Dec.

R.A. Dec.

R.A. Dec.

R.A. Dec.

R.A.

Dec

Greenwich

h. m.

h. m. ^

h. m.

o

h. m. e

h. m. o

b. m. c

«

N.30"I

June 5

4 49'4 N.22'5

23 30'6 S. o'6

6 27-S N.24',

3 ■'■

N.IS'S

2 22-4 N'.i3 - 4

• i 45'5 S. 2-8

21 !3'o S.i6"8
2: 12*7 i6"8

8 2 - 3
S 3*9
8 35
8 42
8 4-9
8 so

n 10

5 lo'l 23*0

3 19-1 N.23-5

6 3ST 23 - l

3 25-2

'7'3

2 36-8 140

2; 47-8 26

7 42'! N.23'6

6 40*0 2i'8

3 49-8

iS-8

2 51-2 I5'S

23 49S 2 4

21 12 4 16 9

n 20

551-6 234

11 4V2 S. 1-7

6 34'3 20-5

4 W9

20'I

3 5'7 '6-S

23 51 '6

21 120 16 9

16 25'7 S. 26*5

6 231 194

4 4°'3

*>'3

3 20*2 1 7 "8

23 53'* * '

21 to'9 S.17'0

N.20"O

.• 3°

6 33-1 N.23.2

21 38 7 S. i3'6

6 io'9 N T . l3'8

5 6*2

N.22'2

3 34-8 N.i8-S

23 54-4 S. 2

Table 26.

Date.

Greenwich Noon

Greenwich Midnight-

Sun.
P B

L

Moon.
P

P B

* Jupiter
*',

L 2

T ,

T3

«

- H'2 -O'l
I2'2 +0'5
to't 1*1

7'9 "'7
5 - 7 »'3

- 3> +2-8

206"4

140*2
74*o

7*8
301*7
235*3

6
— 23*3
-13*1

+ IO"7
+ 22'4

+ 6*7
— 18'9

e 6

-25'4 +1*9

25*5 ''9

25 '5 3

-25*5 +2*0

252*9
277'9
303*0
328*3

o
1 23 -9

95 "5

67-2

:-9't

h. m.
5 4'
4 «3 «

3 42'

3 »'

h. m.
S 34'

SI €

10 8 t

IO 54 t

" 10

i« 25

.. 26

P is the position angle of the North end of the body's axis
measured eastward from the North point of the disc. B, L
are the helio-(planeto-)graphical latitude and longitude of the
centre of the disc. In the case of Jupiter System I refers to
the rapidly rotating equatorial zone, System II to the tem-
perate zones, which rotate more slowly. To find intermediate
passages of the zero meridian of either system across the
centre of the disc, apply to Ti T 2 multiples of 9 h 50 m -5,
9 h 55 m *7 respectively.

The data for the Moon and Planets in the Second Table

are now given for Greenwich Midnight, i.e., the Midnight at

the end of the given day.

The letters m, e stand for morning, evening. The day is
taken as beginning at midnight.

The Sun is moving Northwards till the 22nd, when it
reaches the Summer Solstice and commences to move
Southward. Its semi-diameter diminishes from 15' 48" to
15' 45". Sunrise changes from 3 h 51™ to 3 h 49 m ; sunset from
8 h 4 m to 8 h 18 m . The Sun's surface is likely to repay care-
ful scrutiny, owing to the recrudescence of activity.

Mercury is an evening star, till June 27th. East Elonga-
tion, 23° from Sun, on May 31st. Semi-diameter increases
from 4" to 6". Illumination diminishes from I to Zero.

VENUS is a morning star. Illumination over nine tenths.
Semi-diameter diminishes from 6" to 5}".

The Moon.— Last quarter 4° 4 h 32™ e. New 12 a 6 h 57 m e.
First quarter 20 d 2 h 24 m c. Full 27° 4" 27 m m. Apogee

ll' 1 l h tn. Perigee 26° 2" ***.

semi-diameter 14' 43", 16' 40"

respectively. Maximum librations 3 d 8° W., 10° 7° S., 19° 7° F...
24 7° N. The letters indicate the region of the Moon's
limb brought into view by libration. E., \V. are with
reference to our sky, not as they would appear to an
observer on the Moon (see Table 27).

Mars is still badly placed, but may be observed as a
morning star. Semi-diameter 24/'.

Jupiter is a morning star, in Pisces; in quadrature with
the Sun on 19th. Equatorial diameter 39", Polar 37".
Configurations of satellites at 2 h in.

Jupiter's Satellites.

Day.

West

|

East

Day.

West.

East.

June I

24

3

Junel6

42

3

,, 2

2

O

134

.. 17

43'

O 2

>! 3

3'

O

24

„ 18

3

© 12

., 4

3

r>

U

.. '9

321

4

.. 5

3^1

O

4

„ 20

23

'4

„ 6

O

3'4

2%

., 21

1

O 234

.. 7

1

O

234

.. 2--

02134

., 8

2

O

'34

.. 23

21

34

., 9

;

O

.54

'•

.. 24

3

C 24 i*

.. 10

11

O

2

.. 2;

3

124

11 11

34

[2

.. 20

521

4

,, I-

43*1

.. 2-

I

.. 13

42

5

1

$•

.. 2S

4'

^s

.. "4

41

23

.. 2Q

4

213

.. «S

4

13

•• 3°

421

C 3

The following satellite phenomena are visible at
Greenwich, all in the morning hours: — l d l h 52 ln I. Sh. E.,
3" 12 m I.Tr. E; 2 d 3° 24 m 111. Sh. E. ; 6 J l h 2S m 19" II. Ec.
D. 8" l h 22"' II. Tr. 1'.. l h 27"' 1. Sh. I., 2" 50 m I. Tr. I.;
9 d 2" 17™ I. tic. K„ 2° iZ m IV. Sh. I. ; 13 d 2° 52'" III. Oc.
R. ; 15 J 1" 10"' II. Tr. I., l h 13 ra II. Sh. F... 3" .T I. Sh. I ;
16" h 3i m Z5" I. Ec. D. ; 1 7 a l h 30 m I. Tr. E. ; 1S° 2° 45 m
IV. Oc. R. ; 20 a l h 19™ 58* III. Ec. U.; Z2* h 57™ II. Sh. I.;
'3" 2" 27 m 33' I. Kc. D; 24° l" 6 m I. Tr. I., 1° 27 m II. Oc. R..
2 h l m I. Sh. E., 3 h 24 m I. Tr. E. : 25° h 34 ni I. Oc. R. ;

157

158

26 d O h 41™ IV. Sh. E. ; 27 d 2 h 12 m 48' III. Ec. D
34™ II. Sh. I.

KNOWLEDGE
29" 3'

May 1915.

Saturn is invisible, being in conjunction with the Sun on
28th.

U ran us is a morning star, but badly placed.

Neptune is an evening star in Cancer; diameter 2".

Double Stars and Clusters. — The tables of these,
given three years ago, are again available, and readers are
referred to the corresponding month of three years ago.

Variable Stars. — Stars reaching their maxima in or near

June, 1915, are included. The lists in recent months may
also be consulted (see Table 28).

Meteor Showers (from Mr. Denning's List) :—

Date.

kadiant.

R.A. | Dec.

May 30 lo Aug

.
333 + 2S

Swift, streaks.

Mav— |une ...

280 + 32

Swift.

May |ulv ...

252 - 2!

Slow, trains.

(une — Aug. ..

310 + 6l

Swift, streaks.

„ —Sept. ..

335 + 57

Swift.

„ -July ..

245 + 64

Swift.

„ —Aug. ..

303 + 24

Swift.

Table 27. Occultations of Stars by the Moon visible at Greenwich.

Date.

Star's Name.

Magnitude.

Disappearance.

Reappearance.

Time.

Angle from

Angle from

N. to E.

N. to E.

I9I5-

h. m.

h. m.

June 1

BAC6814

63

2 49 in

58

4 I in

259

.. 3

44 Capricorni

6-o

1 23 111

4'

2 29 III

265

, 16

BAC 3029

Var.

9 25 '

"3

10 18 e

294

, 16

BD+ 17 1979

68

10 He

92

—

, 18

WZC696

7'4

9 2I(

61

—

—

, 21

BD- io°357o

60

8 43'

151

9 44 e

271

, 21

BD-ii°-3 39 8

67

10 26 e

'5'

, 24

4 Scorpii

5 6

II 19 e

41

II 56 t

337

„ 25

WZC 109S

67

11 54 e

141

—

, 26 ...

BAC 6127

47

9 34'

152

10 Je

206

, 27

BAC 6562

5 '9

9 26 t

3 2 5

, 29

wzc 1359

6-S

—

—

4 37 '"

299

1 29

BD-l7°-62i6

62

~

1

10 38 e

232

From New to Full disappearances occur at the Dark Limb, from Full to New reappearances.
Table 28. Long-period Variable Stars.

Star.

Right Ascension.

Declination.

Magnitudes.

Period.

Date of Maximum.

h. in. s.

.

d.

R Andromedae

'9 33

+38 6

56 to 14-

411

1915— May 29

RX Cephei ...

43 9

+81 30

7-4 to 7-9

130

„ June 1

X Camelop. ...

4 34 29

+ 74 58

7'3<° '3'«

142

Fuly 1

R Corvi

12 15 13

-18 47

5-9 to 129

3i8

,, June 26

R Camelop. ..

14 23 35

+ 84 13

7-2 to 13-3

270

,, July 11

S Ursae Min.

15 32 47

+78 55

72 to 11 '6

323

,, Tune 20

S Herculis

16 48 2

+ 15 '5

5'9to 13-1

30S

,, July 21

R Ophiuchi

17 2 53

-15 59

6-o to 13-6

302

,, June 20

R Cygni

'9 34 33

+50

5-9 to 13-8

426

,, June 28

Night Minima of Algol 10 d 3 h -8m, 13 d h '6»», 15 d 9 h -4c, 30 d 5 h -5 m. Period 2 d 20 h 48 n -9.
Principal Minima of (3 Lyrae 13 d 3 h m, 26 d l h m. Period 12 d 21 h 47 m -5.

REVIEWS.

CHEMISTRY.

Quantitative Organic Analysis. — By P. C. R. Kingscott,

B.Sc, A.I.C., and R. S. G. Knight, B.Sc, A.I.C.

283 pages. 51 figures. 8£-in. x 5J-in.

(Longmans, Green & Co. Price 6/6 net.)

The analysis of organic compounds does not admit of
that degree of systematisation which has been found possible
in the case of inorganic compounds. Group reagents can
only be used to a limited extent for the separation of carbon

compounds into separate classes ; and, in examining an
unknown compound, it is necessary to determine its
elementary composition, molecular weight, and physical
properties, as well as to ascertain the presence of distinctive
groups of atoms within its molecule. The object of this
book has been to give a concise, workable description of
all the methods commonly employed ; and, since many of
the processes for the estimation of special radicles are not
readily accessible, the authors have done a serviceable
work in bringing them together in a convenient form. The

May, 1915.

KNOWLEDGE.

159

book will therefore be found of great use both to the student
and to the chemist in practice ; and its value is enhanced by
the inclusion of the methods applicable to compounds of
technical importance, such as sugars, dyestuffs, alcohols,
and oils. Diagrams of apparatus are supplied where
necessary, and full references to the original papers are
given in each case. As a rule, the working directions are
quite clear, though occasionally — as in the description of
the bromine absorption method — further detail would be
desirable. The most noticeable error is the omission of the
final " s " from the name " Wijs," which does not appear
to be a misprint, since it is repeated in another place.

C, A. M.

GEOGRAPHY.
The Home of Man. Part III. America. — By W. C. Brown
and P. H. Johnson. 282 pages. 107 illustrations. 7A-in.
by 5-in.
(George G. Harrap & Co. Price 1 /9 net.)
Part IV. Asia.— By L. A. Coles. 192 pages. 91 Illus-
trations. 7|-in. x 5-in.
(George G. Harrap & Co. Price 1/3 net.)
Although a large number of school geographies has been
published in recent years, these volumes, which are in-
cluded in " The New Outlook Geography " series, should
prove very useful to teachers. The various parts of the world
are examined, from the " human " standpoint, in prefer-
ence to the purel}' scientific, and emphasis is laid throughout
on the relations between population and physical conditions,
the methods being statistical rather than descriptive. The
books are well illustrated by a large number of maps and
diagrams, and numerous questions and exercises are inter-
spersed throughout the text. In Part III the geology of
Central America, as shown in Figure 10, differs radically
from that given in Figure 70, while the " annual rainfall "
maps of the same countries (Figures 20 and 69) likewise do
not agree. Each volume has a useful index and also an
appendix containing tables of trade and other data. The
lack of uniformity in the units employed in the latter is
somewhat confusing, while some of the figures are scarcely
the most recent. A. S.

ORNITHOLOGY.
Field Studies of Some Rarer British Birds. — By John
Walpole-Bond. 305 pages. 9-in. 5J-in.
(Witherby & Co. Price 7/6 net.)
A love of birds and the desire to protect the rarer
ones from extinction are now very widely spread, and many
will be glad to have in collected and revised form the
personal observations of Mr. Walpole-Bond upon some of
the British species, which cannot be called common,
although in his preface he gives the pleasing information
that most rare birds are considered rarer than they are in
reality. We might expect that Mr. Walpole-Bond would have
something to say of choughs and ravens, eagles, buzzards,
and kites, not to mention the peregrine falcon ; and this is
the case; but he also gives us an account of Dartford warblers,
crossbills in Sussex, and cirl-buntings in the same county.
Tin' woodlark, we are told, is much more local than would
be gathered from many books on British birds, and Mr
Walpole-Bond says that in very many places it is one: <>t
extremely rare occurrence, at any rate as a breeding species.
The pied-flycatcher, as studied in its Welsh resorts, is another
bird that is dealt with. The nest is sometimes a joint-stock
affair. Eggs of the redstart have been found in it, and
several kinds of tits have helped to rear a mixed brood.
The usurping and eviction on the part of other small hole-
breeders does not, of course, says Mr. Walpole-Bond, take
origin from any love those birds may have towards the pied-
flycatcher. It is simply owing to the fact that in some
districts there are not enough suitable holes to go round.
We know that in one locality in Wales the pied-flycatcher
takes readily to nesting-boxes, and comes back to them
year after year with hardly the difference of a day. There-
fore there is an opportunity for bird-lovers to attract and
protect this species. W M W

THE SEA.
Nature Notes for Ocean Voyagers. — By Captain A. Car-
penter, R.N., D.S.O., and Captain D. Wilson-Barker,
R.N.R. 181 pages. 139 illustrations. 9-inx6|-in.
(Charles Griffin & Co. Price 5/- net.)
There are many who have to travel on the sea who,
although they have no scientific knowledge of the pheno-
mena and creatures with which they may meet, at the same
time are thoroughly interested in them, and are desirous
of knowing something about their unfamiliar surround-
ings. For these, Captains Carpenter and Wilson-Barker
have written the attractive book under consideration.
Physical features of the ocean are not forgotten. Natural
history, as may be expected, comes in for considerable
attention, and this includes surface life and ocean deposits.
Even old sea monsters are dealt with, and there are chapters
on Weather and on Waves. Among the illustrations to
these are some of the photographs of clouds and of ripples,
for which Captain Wilson-Barker is famous. Not the least
interesting is the final chapter on "Some Old Sea Customs
and Chanteys." W. M. W.

ZOOLOGY.
An Introduction to the Study of Fossils. — By Hervey Wood-
burn Shimer, A.M., Ph.D. 450 pages, 175 figures.

7J-in x 5-in.
(Macmillan & Co. Price 10 /6 net.)
Even nowadays there is still a tendency to keep fossil
creatures distinct from living ones, and in writing this
" Introduction to the Study of Fossils," Professor Shimer
has had in view the students who come to him with little
previous training in biology. His idea is to awake an
interest in the fossils — which are too often looked upon
merely as bits of stone — as once living animals and plants,
connected by the wonderful chain of evolution, with
animals and plants now living. Special emphasis has been
laid on the relation of the soft body to the hard skeleton
or shell, so that the student may reconstruct from the hard
parts preserved in the rocks the appearance of the once
living animal. Briefly the various classes and orders of
plants and animals are reviewed, and, after most of the
paragraphs, instructions and questions are printed for the
benefit of students. The descriptions are necessarily short,
but they are quite sufficient to fulfil the objects of the
author, and to give the student a very fair idea of the animal
and vegetable kingdoms. W. M W.

Some Minute Annual Parasites. — By H. B. Fantham, D.Sc,
and Annie Porter, D.Sc. 319 pages. 58 illustrations.
7i-in. x5-in.
(Methuen & Co. Price 5 - net.)
The importance of the work in zoology, or perhaps we
had better say proto- zoology, which is now being done in
connection with the investigation of diseases is possibly
not realised by the general public Articles in magazines
and exhibits at scientific conversaziones have familiarised
people with the blood parasites causing malaria and sleeping-
sickness . but it needs a popular book, such as the one by
Doctors Fantham and Porter, to make generally known
the many " unseen foes in the animal world " which have
been discovered or unmasked during recent years Not
only are the diseases to which we have alluded considered
in detail, but similar ones which attack animals, other
than man. Spirochaetcs. which the authors have
themselves specially investigated, which are found in many
animals, come m for attention Oysters and mussels aie
troubled with them, while those which cause African tick
and other fevers live m the mites know n a- ' ticks," and are
transmitted In- them to man Coccidiosis is a disease which
plays havoc in the poultry yard and on the grouse moor.
The parasites which eau-e it live in the alimentary .anal
and enormous numbers ol them reduce the lining to a
structureless pulp, with a fatal result 1 [armless and harmful
amoebae, the diseases oi yellow fever and red water, bee
aud silkworm diseases, and many others are simply de-
scribed in " Some Minute Animal Parasites " W M W

NOTICES.

MR. RICHARD LYDEKKER, F.R.S.— We are very sorry

to record the death of Mr. Richard Lydekker, a distinguished
contributor to " KNOWLEDGE," and well known for his work
in Geology and Zoology

ECONOMIC BOTANY.— Messrs. John Wheldon &
Company's catalogue (No. 69) contains the titles of some
hundreds of books and papers dealing with commercial
plants, cotton, dyeing, weaving, brewing, as well as grasses,
sugar, timber, forestry, and tobacco.

MRS. HENRY DRAPER.- We have received a reprint
of an article by Miss Annie |. Cannon, from Science, giving
an interesting account of the life of the late Mrs. Henry
Draper, who. in the same way as Lady Huggins helped
Sir William Huggins, was an enthusiastic and capable co-
worker in astronomy with her husband, the late Dr. Henry
Draper.

RUSSIAN EQUIVALENT TABLES.— In view oi the
increasing importance of trade with Russia, the Central
Translators' Institute, of 265 Strand, has compiled a set of
tables, dealing with the somewhat complicated Russian
weights and measures, which permit of the instant conversion
of British weights, measures, and money into Russian, and
vice versa, and cover all ordinary commercial requirements.
The price is one shilling.

MICROSCOPE MATERIALS.— We have received from
Mr. C. Baker his catalogue of microscope materials. It
contains details of stains and reagents, bacteriological and
other apparatus, mounting sundries, pond-life apparatus,
and mounted specimens. We notice that, in common with
other manufacturers, Mr. Baker has had to advance his
prices somewhat where metal and glass are concerned, and
also in the case of stains.

VILLAGE INDUSTRIES.— Some of the few village
industries which survive are exceedingly interesting. They
could be made most helpful to rural workers, and it should be
possible to revive and introduce others. We hope, therefore,
that the National Council of Toy Industries, which has been
formed, will be able to encourage work which can be done
in cottage homes. The Secretaries may be addressed at
33, Buckingham Mansions, N.W.

PROFESSOR HERDMAN.— Arrangements have been
made for the portrait of Professor Herdman, painted by
Robert Duddingstone Herdman, to be reproduced by
heliogravure process, and issued to subscribers. The cost
will not exceed ten shillings ; and if one hundred applicants
subscribe, it will be but five. Any proceeds, after the
payment for the plate and reprints, will be devoted to
Belgian refugee artists. Particulars may be obtained from
Miss May Allen, Zoological Library, The University,
Liverpool.

THE LATE PROFESSOR TARRIDA DEL MARMOL.
— An appeal is being made for the widow and children of
the late Professor Tarrida del Marmol, who was born in
Santiago, in Cuba, in 1861, of a distinguished Spanish family.
In his boyhood he showed a marked talent for mathematics,
and, later, turned to astronomy. He devoted his pen and
his purse to every forward movement, from constitutional
liberalism to philosophic anarchism. The address of the
Secretary of the Marmol Committee is 92, Selwyn Avenue,
Highams Park, London, N.E.

MR. MURRAY'S QUARTERLY LIST.— Among Mr.
Murray's new and forthcoming works are several dealing
with the war. Dr. Chalmers Mitchell is responsible for one
on " Evolution and the War "; Mr. Theodore Andrea Cook
contributes a series of essays on " Kaiser, Krupp, and
Kultur"; while Professor Muirhead discusses "German
Philosophy and Its Relation to the War." Volumes III
and IV of " The Arts in Early England," by Professor
Baldwin Brown, which will deal with Anglo-Saxon art and
industry in the pagan period, are now promised.

ROAD CONSTRUCTION.— In a paper read recently
before the Society of Engineers Mr. Frank Grove, the

Assistant Surveyor oi the County of Surrey, summarised
the development ol roads in Kngland from the time of the
Roman occupation, and referred in greater detail to those
ol more recent times. He described the nuisance arising
from dust, the extensive damage done to road surfaces,
and the means taken to minimise these troubles. He then
gave an account of the maintenance of the roads in the
County of Surrey, which were more used by motor-cars
than those of any county around London ; and, finally,
he described the methods of construction of the various
types of roads now used.

BRITISH ANTS.— Messrs. William Brendon & Sons
announce the publication, at one guinea, of a work on
" British Ants," by Mr. Horace Donisthorpe, provided
the number of copies subscribed for be sufficient to make
production possible. Hitherto the study of British ants
has been greatly hindered by the lack of a book giving the
classification and descriptions of all the species known to
occur in these islands. Mr. Donisthorpe has been at work
for many years on a work which is expected to consist of
three hundred and fifty pages, seventy figures, and forty
photographs. From the specimen pages it would appear
that great care has been exercised in the preparation of
the book, and that it will contain interesting details as to
habits and life-history. The book is quite ready to go to
press, but the difficulties occasioned by the War have caused
the author to postpone the printing of it until a fuller list
of subscribers has been obtained. Messrs. Brendon & Sons'
address is Plymouth.

ALCHEMY AND PHALLICISM.— At the last meeting
of the Alchemical Society the acting president, Mr. Stanley
Redgrove, B.Sc, read a paper on " The Phallic Element
in Alchemical Doctrine." The lecturer brought forward
further evidence in support of his theory that the doctrines
of the mediaeval alchemists originated in an attempt to
apply, by means of analogy, the accepted religious dogmas
concerning the soul and its destiny to chemical and physical
phenomena. A further source of a priori reasoning was, the
lecturer said, to be found in the rudimentary physiology
of the period. It was natural for primitive man to attempt
to explain the universe anthropomorphically, and this led
to his attributing sex, not only to the world as a whole, but
to inanimate objects. This gave rise to "phallicism," or the
worship of sex ; and so far as the alchemists were concerned,
what the lecturer called " the phallic element in alchemical
doctrine " manifested itself in a belief that the metals
propagated themselves sexually.

BIOLOGY AND THE WAR.— No. 24 of " Papers for
War-time " is by Professor J. Arthur Thomson, and deals
with " Biology and the War." The author points out that
the struggle for existence does not necessarily make for
evolution, and in many cases thins out without sifting.
From a biological point of view war must be regarded with
anxiety, since it impoverishes the race, through the death
of a disproportionately large number of those whom we
can at least afford to lose, and that, far from being in full
accordance with Nature's message to man, it is a reversion
to the crudest and most primitive form of the struggle
for existence. In conclusion, Professor Thomson asks if
this war brings racial impoverishment, as it seems bound to
do, what counteractives are possible ? He thinks that we
may look for a more marked disapproval of selfish forms
of celibacy and a stronger encouragement of chivalrous
marriages. There may spring up a freshened enthusiasm
for all-round fitness and a high standard of health. With
regard to retrenchments, he goes on to say : "To economise
upon the nobler super-necessaries means crippling such
supermen as painters and musicians. May we not try
pinching ourselves in our comforts before we begin starving
our souls?" What the biologist is most concerned with is
the natural inheritance of the race ; but if this is impoverished
it rests with us, each in his own way, to try to secure that
our social heritage may be enriched.

160

May, 1915.

KNOWLEDGE.

CROSS & COLES Modern Microscopy. A Handbook for
Keginners and Students, with chapters on special subjects
by various writers. Fourth Edition, revised and enlarged.
Demy Svo. Pp. xviii + 426, with 113 plates and other
illustrations. I'rice 6s. net.

MUTER'S Analytical Chemistry. Qualitative and Quanti-
tative. Inorganic and Organic. Edited by J. Thomas. B.Sc.
Tenth Edition. Thoroughly revised in accordance with
the New Pharmacopoeia. 252 pp. 56 illustrations
6s. net.

SMALLWOOD'S Text Book of Biology, for Students in
Medical. Technical, and General Courses. Royal Svo.
Pp. 286. with 13 plates, plain and coloured, and 243
illustrations in the text. 1 'rice 10s. 6d. net.

".4 charmingly written, liberally illustrated, and
singularly suggestive text-hook. ' ' — LA NCE T

BAILLIERE, TINOALL & COX, 8. Henrietta Street. Covent Garden, London.

n

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May, 1915.

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KNOWLEDGE.

vu.

SPRING MICROSCOPY.

WATSONS
"CLUB" MICROSCOPE

is the Ideal Instrument for Field Work.

PORTABLE COMPACT

Is made throughout with the
care and consideration of detail
which has made the name of
"Watson" on a microscope a
guarantee of satisfaction.

A few paints to consider:—

It packs into a leather sling
case 7J X 4J X 3i inches.
Accommodation in case for
2 eyepieces — 4 objectives —
condenser — forceps — dipping
tubes — nosepiece.

A 3" objective can be focussed
with ease.

Every fitting is standard size.

A Mechanical Stage can be
fitted.

The instrument is adapted for
high or low power work.

Price: Club Microscope as figured eycz g\ fk

and described, in stiff leather case ... *»0 \J %J

Send alpostcard for Section I of Catalogue No. 2, Full
details of this Stand will be found on page 94. Also
details of 32 other instruments at varying prices.

ALL. ARE BRITISH MADE.

The "Club" Microscope.

All bearings slotted and sprung.

Collecting Apparatus.

mfammmmimmmmmi* TiT" (hi n n tiiim

Complete Outfits:

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Also Complete Outfits at 15/-, 17/6.

Full specification of the above, also ColIectingTubes,

Troughs, Botanical Presses, Geological Apparatus,

Ac, in CATALOGUE No. 2, Section 2, gratis on

request.

WATSONS MICROSCOPIC OBJECTS.

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all specially selected, and guaranteed typical. Catalogue

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Optical Works— HIGH BARNET, HERTS. ESTABLISHED 1837.

THE FOCOSTAT LENS.

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THIS Lens fits the handle of a Dissecting Instrument, Mapping
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It fixes on to the handle of the Instrument itself, and never
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For the Botanist, Entomologist, or Zoologist, and for
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Those who have hitherto used a watchmaker's eyeglass or
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The lens is very powerful and can be set by means of the
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after which it does not require to be altered.

p*~ See Editorial Notice in Knowledge, May, 1912, page 193.

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NEW MODEL

FS and FFS

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Oil Immersion.

Deal l.ngth. N.A. Price.

Focal length. N.A. Price.

1-in. .. 030 .. £4 lO

O

1 in. .. 1'35 .. £8 10

O

{ „ 030 . . 3 O

o

J „ .. 140 .. 10 O

O

$ „ .. 0-63 .. 4 O

o

,»,„ 1"35 .. 8 10

O

J „ 0-95 ..SO

o

&„ .. 140 .. 10 10

O

NATURE says: "Compare very favourably in all respects with
similar lenses of other makers at double the price."

Catalogue gratis on application.
UNIVERSITY OPTICAL WORKS,

81, TOTTENHAM COURT ROAD, LONDON.

BOTANIGAL COLLECTING CASES

3/-
3/9
4/9
5/9
10/6

'nland Postage.
... Ad.

5d.

bd.

bd.
... Sd.

Pocket

sizes, 1/9
2/3.
(Postage 3d.)

and

Shoulder Straps, 1/2.

For the above and other

Collecting Apparatus,

see Catalogue C 13

post free.

GARNETT, Ltd.,

Opposite the
"versity

MANCHESTER.

FORMS A MOST INTERESTING AND LASTING GIFT.

THE "SIMPLEX" BAROGRAPH.

(REGISTERED No. 468791.)

In Oak Case, glazed top and sides. Records on a Weekly Chart. OQ -i ft C

Price, with a year's supply of Charts, Ink and Instructions, complete dbll 10 D

W Special Illustrated List of Barographs and Thermographs

(covering various patterns, from £3 15s,), post free.

SOZ.fi MAKERS:

PASTORELLI & RAPKIN, Ltd.

(ESTABLISHED 1730),

ACTUAL MAKERS OF ALL KINDS OF METEOROLOGICAL INSTRUMENTS,

Contractors to H.M. Government,

46, Hatton Garden, London, E.C.

STANDARD INSTRUMENTS OF ALL KINDS.

Illustrated Price Lists Post Free.

*»* We pay carriage and guarantee safe delivery within U.K. on all our Instruments.

Printed for the Proprietors (Knowledge Publishing Company, Limited), by John King, Ealing and Uxbridge.— May, 1915.