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VOLUME XXXVIII. NUMBER 559.
New Series. Volume XII. Part 2.
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CONTEXTS.
Chapters ik Spectrim Analysis. I.
By \V. Marshall Watts. D.Sc. iS
Correspondence 37
Flora Selborniensis ... 38
Solar Disturbances during December. 1914.
By Frank C. Dennett. 43
The .Amateur in Astronomy (continued).
By \V. F. Dcnniit^. F.R..A.S. 44
The Zoological Society. 44
The Teeth of the Wo.mbat and the Beaver. ... 47 The Face of the Sky for March.
By A. C. D. Crommelin. B.A.. D.Sc. F.R.A.S. 47
Regeneration ... ... 48
Notes. —
Astronoinv.
By A. C. D. Crommelin. B.A.. D.Sc. F.R.A.S
Notes 'continued) : —
Botany. By Professor F. Cavers. D.Sc. F.L.S. 51 Chemistry.
.B.v C. Ainsworth Mitchell. B.A.. F.I.C. 52
Geography By A. Scott. M.A., B.Sc 53
Geology. By G. W. Tyrrell. A.R.C.Sc. F.G.S. 53
Meteorology. By William Marriott, F.R. Met. Sac. 53
Microscopy. ... By J. E. Barnard. F.R.M.S. 54
Photography. ... ... ... By Edgar Senior. 55
Physics. By J. H. Vincent.. M. A., D.Sc. A.R.C.Sc. 56
Radio-.\ctivity. By .Alexander Fleck. B.Sc. 57
Zoology.
By Professor J. .Arthur Thomson. M.. A. . LL.D. 58
Reviews 59
Notices 64
51
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Index of Spectra
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Appendix V contains .\ir, .\ldebaranium. Aluminium, .\lumina, Ammonia, Antimony, Argon, Arsenic, Barium, BervUium, Bismuth, Boron, Bromine, Cadmium, Caesium, Calcium, Carbon. Cassiopeium, Cerium, Chlorine, 12s. 6d.
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CF ^TERS IN SPECTRUM ANALYSIS.
By W. MARSHALL WATTS, D.Sc.
L— Law and Order ix Spectra. A. Line Spectra.
Sprang vi\-id fc: And next delici Fell the kind Iv Then the pure c Ethereal played Emerged the de The heavy-skirte \Miile the last c Died in the faiai.
" First the flaming red . the tawny orange next ;
How, by whose side - )f all-refreshing green ;
hat swells autumnal skies, then, of sadder hue,
d indigo, as when
jning droops with frost ; ■ ngs of refracted Ught
iolet away."
Science moves but siwly, slowly, creeping on from point to poiu
The scientific in- quisitive mind, temperament wh: extent the beaut\- but he is never - and explain the ■ vestigates; and h he has succeeded i* Others may be beauty, and ma; the phenomena b; of profanation. I of all attempts t discord, and ther the rainbow with
Can there be spectrum (or, at tiit sight, more uninterestin than a catalogue of he wave-lengths of the lines which make up the pectrum) ? Yet I venture to
,'ator is a man with an in- . may possess the aesthetic ■an appreciate to its fvdlest any phenomena he observes, : led until he can understand :i of the phenomenon he in- only completely happy when .ucing the matter to formulae, lied with the perception of ard the attempt to express thematical formulae as a sort e known musicians impatient Dlain harmony or concord or a artists capable of painting ; colours in the wrong order! a;.\hing more beautiful than a
think that there is, so to speak, more beauty in the law and order revealed by a patient study of a dry catalogue of wave-lengths than that perceived by the mere contemplation of the harmoniously grouped colours of the spectrum visible to the eye.
" The harmonious spheres Make music, though unheard their pealing By mortal ears."
Even in the early days of spectrum analysis it was felt that there must be some connection between the \-ibrations to which the bright lines of a glowing gas are due, and the earlier attempts at tracing this connection were based upon analogy with music. In following up such an analogy we must employ numbers of \'ibrations instead of wave- lengths. The number of vibrations per second of the red Hght of incandescent hydrogen is obtained by di\-iding the velocity of light, 300,000 kilo- metres per second, by the wave-length, which is 6563 ten millionths of a millimetre for the red Hu line. This gives 457-108 million million vibra- tions per second. To avoid these unwieldy numbers it is preferred to divide the wave-length into one centimetre, or 10* ten milUonths of a millimetre,* so that we obtain the number of oscillations made while light is travelling one centimetre. This is called the " oscillation-frequency." In the visible portion of the spectrum, \, the wave-length in tenth-metres, is represented by four figures before the decimal point, and 10-/\, or 10-\-^ is
* One-ten milliontlx of a millimetre is called one " tenth-metre.'
33
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FEBRUARY, 1915.
CHAPTERS IN SPECTRUM ANALYSIS.
By W. MARSHALL WATTS, D.Sc.
L — Law and Order in Spectra. A. Line Spectra.
" First the flaming red Sprang vivid forth ; the tawny orange next ; And next delicious yellow, by whose side Fell the kind beams of all-refreshing green ; Then the pure blue, that swells autumnal skies. Ethereal played ; and then, of sadder hue. Emerged the deepened indigo, as when The heavy-skirted evening droops with frost ; While the last gleamings of refracted light Died in the fainting violet away."
" Science moves but slowly, slowly, creeping on from point to point."
The scientific investigator is a man with an in- quisitive mind. He may possess the aesthetic temperament which can appreciate to its fullest extent the beauty of any phenomena he observes, but he is never satisfied until he can understand and explain the cause of the phenomenon he in- vestigates ; and he is only completely happy when he has succeeded in reducing the matter to formulae. Others may be satisfied with the perception of beauty, and may regard the attempt to express the phenomena by mathematical formulae as a sort of profanation. I have known musicians impatient of all attempts to explain harmony or concord or discord, and there are artists capable of painting the rainbow with the colours in the wrong order! Can there be anything more beautiful than a spectrum (or, at first sight, more uninteresting than a catalogue of the wave-lengths of the lines which make up the spectrum) ? Yet I venture to
think that there is, so to speak, more beauty in the law and order revealed by a patient study of a dry catalogue of wave-lengths than that perceived by the mere contemplation of the harmoniously grouped colours of the spectrum visible to the eye.
" The harmonious spheres Make music, though unheard their pealing By mortal ears."
Even in the early days of spectrum analysis it was felt that there must be some connection between the vibrations to which the bright lines of a glowing gas are due, and the earlier attempts at tracing this connection were based upon analogy with music. In following up such an analogy we must employ numbers of vibrations instead of wave- lengths. The number of vibrations per second of the red light of incandescent hydrogen is obtained by dividing the velocity of hght, 300,000 kilo- metres per second, by the wave-length, which is 6563 ten millionths of a millimetre for the red Hu line. This gives 457-108 million milHon vibra- tions per second. To avoid these unwieldy numbers it is preferred to divide the wave-length into one centimetre, or 10^ ten millionths of a millimetre,* so that we obtain the number of oscillations made while light is travelling one centimetre. This is called the " oscillation-frequency." In the visible portion of the spectrum, X, the wave-length in tenth-metres, is represented by four figures before the decimal point, and lO'/X, or lO^X"' is
* One-ten millionth of a millimetre is called one " tenth-metre."
33
34
KNOWLEDGE.
February, 1915.
represented by five point. For example, the hydrogen-vacuum tube are Wave- lens;th.
Ha 6563-042
H/i 4861-49
H-y 4340-66
Hd 4101-89
figures before
the decimal
four lines seen in a given thus : — Oscillation- frequencv.
15236-84
20569-82
23038-0
24379-0
Professor Johnstone Stoney, guided by musical Table 7.
|
Observ'ed. |
Calculated from the formula |
|
|
(I.A.) |
O.F. -27419-805- 109679-22 |
|
|
Ha |
6562 -793 |
6562-793 |
|
H^ |
4861-326 |
4861-327 |
|
Hy |
4340-467 |
4340-466 |
|
H5 |
4101-738 |
4101-738 |
|
He |
3970-075 |
3970-075 |
|
Hi- |
3889-051 |
3889-052 |
analogy, endeavoured to explain the rhythmical arrangement of lines on the theory that they were overtones of a very low fundamental vibration, since Ha, H^, and Ho might be the twentieth, twenty-seventh, and thirty-second harmonics of a fundamental vibration of oscillation-frequency 761 -845. But there was no place for H-y in this arrangement, and no reason why these harmonics only should be observed ; nor does the theory account for the extensive series of lines observed in stellar spectra by Sir William Huggins and others. It is now generally admitted that such theories will not account for the facts.
The first striking success in the attempt to explain these regularities was obtained in 1885 by Pro- fessor Balmer, who found that the hydrogen lines were connected in a simple manner with the suc- cession of natural numbers from 3 onwards, the wave-lengths of Ha, H^, Hy, Ho, and so on, being f' i' If' S' ^^"^ so on, of the wave-length 3646-1 of a " head " in the violet, to which the lines crowd continually closer and closer. Otherwise expressed,
X = 3646-14
m'
where m
is put equal to or, if we use
w — 4 ' 3, 4, 5, and so on, in succession oscillation-frequencies, O.F. = 27418-75 (1 - Altn^). We may obtain an interesting representation of the law which holds in this spectrum by measuring the distance of the lines from the " convergence- frequency " at 27418-75, which we may write C.F.
4C.F.
We have C.F. — O.F. =
V = — . then y^ = .^ .^ ■^ m -^ 4C.F.
m'
or, if we put
(C.F. - O.F.) , which is the
equation of a parabola.
Figure 27 illustrates this, in which the upper part shows the series of hydrogen lines which have been
observed, and the lower shows the parabolic curve which connects the stars, plotted with a scale of 1 jm along the left margin, and a scale of oscillation- frequencies along the bottom of the diagram. Along the right-hand margin is shown a scale of 1 jni^ ; and, when the lines are plotted with this and the bottom scale, it is seen that all the points lie accurately along a straight line. The formula given above, namely, 1
r
may be written
.,2 ■
4C.F.
1
m^ 109675
(C.F. -O.F.)
(C.F.-O.F.),
or
O.F. =27418-75 -
109675
nr
The researches of Kayser and Runge, of Rydberg and others, have shown that in most spectra, though the lines may appear to be distributed at random, yet in very many cases series of lines.
|
Table |
8. |
|||
|
Observed. |
Calculated. |
|||
|
Vacuum- |
Chromosphere. |
O.F. =27418-75 |
||
|
109675 |
||||
|
Ames.* |
Dyson, t |
Evershed \ |
Mitchell.§ |
m- |
|
6563-042 |
6563-045 |
6563-07 |
||
|
4861-49 |
4861 -527 |
4861-90 |
4861-52 |
|
|
4340-66 |
4340-634 |
4341-17 |
4340-64 |
|
|
; 4101-85 |
4101-92 |
4101-900 |
4102-00 |
4101-90 |
|
3970-25 |
3970-21 |
3970-212 |
3970-48 |
3970-24 |
|
; 3889-15 |
3889-15 |
3889-15 |
3889-47 |
3889-21 |
|
1 3835-6 |
3835-53 |
3835-53 |
3835-69 |
3835-54 |
|
' 3798-0 |
3798-06 |
3798-00 |
3798-15 |
3798-05 |
|
3770-7 |
3770-79 |
3770-73 |
3770-90 |
3770-79 |
|
3750-25 |
3750-32 |
3750-27 |
3750-41 |
3750-30 |
|
: 3734-15 |
3734-52 |
3734-53 |
3734-63 |
3734-52 |
|
3721-8 |
3722-05 |
3721-98 |
3722-20 |
3722-12 |
|
3711-9 |
371212 |
3712-13 |
3712-20 |
3712-12 |
|
3704-00 |
3704-01 |
3704-03 |
3704-00 |
|
|
3697-29 |
3697-28 |
3697-35 |
3697-30 |
|
|
3691-70 |
3691-70 |
3691-78 |
3691-71 |
|
|
3687-00 |
3686-96 |
3686-97 |
3686-98 |
|
|
3682-92 |
3682-94 |
3682-96 |
3682-96 |
|
|
3679-50 |
3679-52 |
3679-48 |
3679-51 |
|
|
3676-54 |
3676-51 |
3676-48 |
3676-51 |
|
|
3673-90 |
3673-87 |
3673-96 |
3673-91 |
|
|
3671-46 |
3671-53 |
3671-45 |
3671-63 |
|
|
3669-58 |
3669-55 |
3669-60 |
3669-60 |
|
|
3667-89 |
3667-83 |
3667-91 |
3667-82 |
|
|
3666-21 |
3666-25 |
3666-23 |
3666-24 |
|
|
3664-78 |
3664-74 |
3664-80 |
3664-82 |
|
|
3663-58 |
3663-55 |
3663-56 |
3663-55 |
|
|
3662-35 |
3662-36 |
3662-37 |
3662-36 |
|
|
3661-35 |
3661-31 |
3661-42 3660-47 3659-88 3658-80 3658-19 3657-40 3656-80 |
3661-36 3660-42 3659-86 3658-80 3658-07 3657-41 3656-83 |
* Ames, Phil. Mag., 1890, XXX. 33. t Dyson, Phil. Trans., 1906, CCVI, 403.
+ Evershed, Phil. Trans., 1903, CCI, 457.
§ Mitchell, Astrophys. Joiirn., 1913, XXXVHI, 407.
February, 1915.
KNOWLEDGE.
35
.\ li! ONIS
I 77 0 I V ^ \ K
IT I r
1 ' E. M4<
a. Lyr/E
HHffT^iW I
6 n
Figure 25.
Heliu-tn ■ Rl&EL
bMiciwTn. -Titanii/
a. Cy&nt
hrom Spectrograms
Figure 26. The Spectrum of Hydrogen as observed in the Stars.
36
KNOWLEDGE.
February. 1915.
^m/^ JO 9]V3^
February, 1915.
KNOWLEDGE.
37
similar to the hydrogen series, can be traced. In each series the Hnes succeed each other with great regularity, becoming closer together and diminish- ing in intensity as we pass from red to violet, thus approaching a " head " or limit. Several series may coexist in the same spectrum. These series may be represented by formulae. It appears probable that the number 1 09675 is the same for all spectra and all elements, so that it is a " universal constant " of Nature. Rydberg's general formula is
O.F. = C.F. - 1^5^,, which differs from the simpler
formula for hydrogen only by having another term, fi.
The complexity of a spectrum is found to depend in some way upon the position of the element furnishing it in the Periodic Table of Mendelejeff, or, in other words, the lower the atomic weight of an element, the simpler its spectrum. Thus hydrogen, with atomic weight 1, has the simplest of all spectra. Probably fi is not really zero, but * Curtis, Proc. Roy. Soc, 1914, XC, 605.
has some very small value. Curtis* has recently shown that the wave-lengths of the first six hydro- gen lines are given with extreme accuracy by giving to /J. the value 0-0000069, as shown by the following comparison (see Table 7), in which the wave- lengths are given in terms of the International Unit.
The series of hydrogen lines now known consists of thirty-five Unes : of these only the first thirteen have been observed as bright lines in the vacuum tube ; the rest occur as dark lines in the spectra of stars, as seen in the reproduction of Sir William Huggins's photographs (see Figures 25 and 26), or as bright lines in the spectrum of the Sun's chromosphere. The latest determinations are brought together in Table 8.
The series of stellar lines observed by Pickering in f Puppis (see " Knowledge," 1914, Volume XXXVII, page 59) is given approximately by the
formula O.F. = 27418-75 -1^^^^„. But it is
more probable that these lines are due to helium, f t Fowler, Phi!. Trans.. 1914, CCXIV, 256.
CORRESPONDENCE.
HIGH TIDES AT FREMANTLE. To the Editors of " Knowledge."
Sirs, — The following information about the Fremantle tides. Western Australia, may be of value to your corre- spondents on this subject. I have been engaged upon an analysis of these tides, and am therefore in a position to give (H) the semi-range in feet and (K) the phase-constant for the various tides.
In Table 9 appear the H and K of those com- ponents that evidently are the chief controlling factors of the Fremantle tide. It shows very clearly that the Luni-solar and Lunar declinational are the two main ones to be considered.
portion of the Swan River extends past Perth, about fifteen miles from Fremantle, and beyond that the river is of \-ery small extent, and there is no current to speak of ; in fact, ten miles farther on it dwindles to quite a small stream. The Darling Range, where it takes its source, is only a comparatively low elevation, and consequently there is no head of water. As to ocean currents, there is certainly one passing along the coast from south to north, but its rate is only of small account. The chief cause of irregularity in the Fremantle tides is, I think, to be looked for in the prevailing winds.
This peculiarity can very probably be accounted for by the disturbing influences of the wind and weather on the comparatively small range of tide prevailing at Fremantle,
Table 9.
|
Title. |
Name. |
Period. |
Jlean of Years 1911-12.* |
|
|
H. |
K. |
|||
|
O P Q :m., S, |
Luni-Solar Declinational ... Lunar Declinational Solar Declinational {mp"c^"n°-^-^--' Mean Lunar „ Solar |
Diurnal ... Semi-diurnal |
Ft. 0-431 0-320 0-130 0-079 0-112 0-109 |
0 310 319 284 325 319 318 |
* Figures for 1908, 1909, 1910 analysed by Mr.
H K
Ft.
Ki 0-445 319
O -322 324
P -144 313
Of the long-period tides the Solar Annual is probably of most importance, but the values for different years for these tides do not agree very well, and therefore I have not included them.
One of your correspondents suggests, as causes of irregu- larity, strong river flows or strong ocean currents. In this connection I would point out that the estuary or salt-water which, except at certain short periods during each month, when it exceeds two feet six inches, rarely averages more than eighteen inches ; thus, should a strong easterly or
Cooke are as follows (the agreement is good) : —
H K
Ft.
Q 0-083 333
M, -116 325
S/ -109 318
nor'-easterly wind be blowing, the theoretical time of high water is almost certain to be delayed, and the height also diminished. On the other hand, the sou'-wester or sea breeze banks up the water to a greater or less degree, dependent upon its intensity, accelerating the time of high water, augmenting its height and prolonging its duration. This would be especially noticeable during a westerly blow, and the exceptional height often reached by the tides during the winter months is almost solely due to the banking up of the water against our western coast Une ; although
38
KNOWLEDGE.
February, 1915.
in this connection it must be remembered that the great tide-wave which travels along the south coast ol the continent from east to west is retarded by a westerly wind, and its height necessarily increased, and consequently there occurs an additional banking up of the water of the ocean off Cape Leeuwin, which makes its effect felt to a greater or less extent northwards.
" Thus, when the Moon is in Perigee, the tides are invariably higher and the range greater than in Apogee. This is onlv to be expected, for its attractive force is then at a maximum. So in this respect, at all events, the Fre- mantle tides conform to the generally recognised law. On the other hand, we might expect to find some regular sequence of change existing between the tides and the phases of the Moon, but a comparison between the times and heights of high and low water with the age of the Moon fails to dis- close any existing connection ; in fact, it only still further serves to emphasise the complications present in the tide- governing forces, and to demonstrate the difficulties likely to be met with in an attempt to accurately explain them. For the greatest and least ranges occur both at the change and full of the Moon alike.
" It should be noted in this comparison that at about the time of first quarter, and again at last quarter, the diurnal tide, namely, one high and one low during the day, is almost invariably in evidence. It also may be taken as a general rule that the highest tides and greatest range occur about the time of Moon's first quarter, although this sometimes breaks down. At the time of full or new Moon the semi-diurnal tides often make their appearance, marked by small range and great irregularity. But it sometimes happens, as mentioned above, that the highest tides and the greatest range take place at these times, with the almost certain prevalence of a diurnal tide.
" A comparison, however, with the Moon's position in
declination shows that, when the Moon is on the Equator, the least range occurs, the variation in water-level being about one foot, and also great irregularity in the times of high and low water is apparent. Very little reliance can be placed upon the tidal predictions at this period. Often, for quite a considerable length of time, the water remains unchanged in level. The semi-diurnal tides, namely, two highs and two lows during the twenty-four hours, are also in evidence, but the secondaries are sometimes barely perceptible, the difference between the heights of this inferior high and low water being only a few inches.
" As the Moon moves north or south of the Equator, the range gradually increases, and the tidal curve becomes regularly diurnal in character. More dependence also may be placed upon the predicted times as the Moon's distance from the Equator increases.
" Contrary to what might be expected, the highest tide and greatest range happen when the Moon is at its farthest north point, and not at its greatest south declination, when the Moon would be almost directly over Fremantle, and would thus be in a position to exercise the maximum attractive force on the water.
" It may be stated, therefore, with some degree of cer- tainty, that the Fremantle tides depend to a large extent upon the Moon's declination, and from its position the range of tide may be gauged fairly accurately ; but the irregularity in the occurrence of successive highs and lows, although most marked when the Moon is on the Equator, is still to be expected when the Moon attains her greatest north or south dechnation."
H.
The Observatory, Perth, W.A.
B. CURLEWIS,
Acting Government Astronomer, Western Australia.
FLORA SELBORNIENSIS.
February, Second Month [Continued). 22nd. — For the Primrose the Linnean name is used, which still stands at the present day. In a similar way Gilbert White first wrote the name of the Thrush, by which we now know it, but afterwards replaced the specific name by a phrase. He likewise takes out the specific name of the Chaffinch, and corrects the name of the Titmouse from ater to major. The Skylark is now Alauda arvensis.
March, Third Month. As the Spring is now beginning to come on, the number of entries naturally very much increases.
3rd. — Torquilla is now the specific name of the Wryneck. The Wood Laurel is Daphne laiireola. The Black Hellebore is Hellehorus foetidns. The Long-tailed Titmouse is now Acredula. Lady-cows are presumably Lady-birds.
4th. — Chickweed Speedwell is Veronica agrestis.
5th. — The Common Chickweed [Stellaria media). This plant, with the Common Groundsel and the Veronica just mentioned, are among the plants which may be found in flower during every month in the year. The Missel Thrush is Turdus viscivorus. The Peziza is possibly P. aurantia.
6th. — The Red Dead Nettle is Laniium purpnreuni. The Common Wren is Anorthuria parvitla. The Clothes Moth is Tinea pellionclla. The Yellow Hammer is now Emheriza citronella. Gctim nrhaniim is the Common Avens ; Wild Cicely, Anihriscus sylvestris ; Herb Gerard, Aegopodium podagraria ; Fool's Parsley, ActJnisa cynapium ; and Goose Grass, Galium aparine.
7th. — We now call the Wood Lark Lullttla, the Rook Trypanocorax frugilegus, and the Jackdaw Coloeus monedula.
8th. — The first-mentioned Butterfly is the Brimstone [Gonepterix rhamni), and the others are pre- sumably small Tortoise-shells [Vanessa urtica). We know the Blackbird now as Merula merula).
9th. — The Hedge Sparrow is Accentor modularis. Dog's Mercury we call Mercurialis percnnis. The Wood Strawberry is Fragaria vesca. The Ringdove is Columba palumbus. There is an interesting observation with regard to the Field Cricket [Grylliis campestris) .
10th. — Wormwood is now Artemisia absinthium.
February, 1915.
KNOWLEDGE.
39
Si.
/£t^^^^ /t^^i^ ALAx^'it^-e^ /Mj cJaJ^6A£j.^/^-6yi
•^zioL^ aaMti Ic^^ <rJUt.^ ^^^^» ^cluj>Ll thic^£ui^_
J^fij//- ^^ i^e^Ju^^ S^/&^ a^^^T^uO g^/^l^j^ ^-t^e^t-.
:/jufW^, ._-
%) '^O^^.
^^AZ-A-JtJ
'° KNOWLEDGE. P,3,„,,,_ ,,,,_
xf^r^ A->»-^. /•>■■> ^ }^^^f^,n ^fffffffff^ f^A^^/^^_ J/'^^,./j^^
(/tc /<?^^?* ^e^-t^ -/-^€L>, a^fi/^iUA^^Jt,, ^rLr&Af, <uHit,/>t/r/L a^ /^^fct ^UcLf ^LJi!^^^ £^^ejy i^^^:
^. JW j£j£^/L£Mt^^ £z,M.i//.AL t)~il^^JL^^ ^-IL&ttdJL , /£f^^>^^f^:
February, 1915. KNOWLEDGE.
(fit ^-iteU /r/y&^ /h^jCLcA , kJtuc^ ^^s^^LC£L^ ^/i>€eL.
J/e^ ^B^^xS^^ '^^hJ-mQ^ &-tit^X&}€Q, eLA^e&tOL^yf, i^^i/^ cLa^'A^m^^ SumIiLal (HtAjL^K. AOfiLM,, MJttA^^^t^chi .
^2^A/a£^ &^ a^titxfjL'A^-^ ^ ^tJLJ^UU^ IHUMJU^^ ^/ifiO^
yfa^iHj] yya£^, /&t-e,>€yhf.
'' KNOWLEDGE. Februarv. 1915.
/^UttAS>. ^fa^ ft/^^A^.^.^/A ^^Jf!^^' ^'
SOLAR DISTURBANCES DURING DECEMBER, 1Q14
By FRANK C. DENNETT.
NoT\%aTHSTANDixG the poor meteorological conditions which prevailed during the month, only three days (December 6th, 11th, and 28th) passed on which no telescopic examination was made, and the Sun appears never to have been free from spot disturbance. The longitude of the central meridian was 139' 28' at noon on December 1st.
Nos. 43 and 44 of the No^^embe^ list were visible until December 9th and 10th respectively, and therefore reappear upon the present chart.
No. 43a. — A group of pores, which broke out on December 2nd in front of No. 43, and continued until the
on the 21st and 22nd, and one was situated a little to its south-west on the 23rd. The spot was last seen on the 24th.
A pore, not measured, but estimated to be in the position shown by a tiny cross, near longitude 134°, S. latitude 22°, was only visible on the 24th.
No. 4S.-^-A faculic disturbance was seen coming round the south-eastern limb on December 24th, and on the 25th was found to be connected with a spot nine thousand miles in diameter, which was last seen by the writer on January- 2nd.
No. 49. — Two pores, only observed on December 31st, separated by some fiftv thousand miles.
DAY OF DECEMBER, 1914.
|
"f |
? |
» |
a |
?. |
& |
? |
^ |
r |
»i5" |
2- |
a 1 |
2S |
7! |
a |
as |
^t- |
a |
f |
21 |
2a |
19 |
ffi |
17 |
16. |
'? |
t |
? |
•I |
||||||||||
|
J |
9 |
♦* |
4j |
i, |
3a |
1 |
«6 |
s |
||||||||||||||||||||||||||||||
|
) |
■•; |
•"- |
•.»,. |
20 |
||||||||||||||||||||||||||||||||||
|
'■ |
3 |
|||||||||||||||||||||||||||||||||||||
|
rfl |
n\ |
|||||||||||||||||||||||||||||||||||||
|
to |
"v |
|||||||||||||||||||||||||||||||||||||
|
(/ |
1 |
^ |
•^ |
• |
||||||||||||||||||||||||||||||||||
|
so |
0 |
'J |
f. |
|||||||||||||||||||||||||||||||||||
|
ts |
\ |
i |
47 |
pen |
N. |
OnjDi04050607D
% lOO 110 IM 130 »0 ISO 160 170
190 iOO 30 SO IX no 250 »0 270 JU 2X1 >» m »0 no 340 iSO M
5th. Its greatest length, on the 3rd, was seventy-two thousand miles.
No. 45. — A group first seen as two considerable spots just round the limb on the 3rd. The eastern spot was the largest, with three or four umbrae. Some pores helped to make up the group on the 8th. The length of the group was sixty-four thousand miles, and the greatest diameter of the spot eleven thousand miles. It was last seen on the 14th, when it appeared as a group of five pores in a facuUc disturbance.
No. 46. — A fine group, which was found to have broken out on the 12th, consisted of two considerable spots about ten thousand miles in diameter, with some pores between them, fifty-six thousand miles in length. It was last seen near the hmb on the 19th.
No. 47. — A spot ten thousand miles in diameter, first seen on the 18th a little within the limb. Two pores followed it
Faculic disturbances were near the north-western limb on December 1st (215°, 19° N.), 5th (160°, 16° N.), 14th, 24th (274°, 19° N.), 26th, 27th (216°, 20° N., and 204°, 18° N.), and 29th ; north-east on December 1st (75°, 24° N.), 16th, 27th (86°, 13° N.), and 31st; south-west on December 5th, 16th (21°, 25° S.), 20th (320°, 15° S.), and 29th ; south-east on December 8th (in which No. 46 afterwards developed), 23rd, 27th (south of No. 48, and 96°, 27° S.), and 29th (52°, 14° S.).
Our chart is constructed from the joint observations of Messrs. John McHarg, A. A. Buss, and the writer.
A second chart is also appended, showng the distribution of the whole of the spot disturbances of the past year. As compared with pre\-ious year-charts, it will be noticed that the spots, as a whole, are much farther from the Equator, are more numerous than in the three previous years, and are more evenly distributed.
DISTRIBUTION OF SPOT DISTURBANCES DURING 1914.
|
^ |
" |
S 40 |
|||||||||||||||||||||||||||||||||||
|
. |
|||||||||||||||||||||||||||||||||||||
|
-. |
' |
■ |
■» |
• « |
& |
1 1 |
®^ |
«*-. |
••>- |
20 |
|||||||||||||||||||||||||||
|
iu |
in |
||||||||||||||||||||||||||||||||||||
|
■R |
iO |
||||||||||||||||||||||||||||||||||||
|
\ |
• |
?f> |
|||||||||||||||||||||||||||||||||||
|
' |
• |
.',' ' |
v« |
■* |
iO |
||||||||||||||||||||||||||||||||
|
r\ |
|||||||||||||||||||||||||||||||||||||
|
N |
tcsx |
N |
0 10 20 30 «l 50 60 TO 80 90 wo 110 120 1» HO 150 160 m m 190 MO 110 UO tX ViO 250 !60 270 280 »0 300 3(0 J20 SW M 350 560,
B 43
KMOWLBOGE.
Fuic,
*«V, Uis,
^/^u/j (''i*/j.J^€^ ^f%f^
/&/ /f/fM^
^„/. r^/^jJ f^f^ /^/vv/^. ^^*^#^ MA* A V /
/
^f^ A
,/^# /</• /^*^-'
V
•^^^.z -V-''^ ^''//^
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DLAR STURBANCES DURING DECEMBER, 1914
By FRANK C. DENNETT.
.VITHSTAXDI>:
liled durinp; i
■md 28th) p:
ii;ide, and x\
spot distill
lian was 139
-. 43 and 4-) liber 9th ani: the present
43a.— A :
Tiber 2nd in
•!■ meteorological conditions which ;., only three daj^s (December 6th,
1 which no telescopic examination
appears never to have been free
The longitude of the central
t noon on December 1st.
November list were visible until spectively, and therefore reappear
of pores. 1 Xo. 43.
which broke out on and continued until the
on the 21st and 22nd, and one was situated a Little to its south-west on the 23rd. The spot was last seen on the 24th.
A pore, not measured, but estimated to be in the position shown bj' a tiny cross, near longitude 134°, S. latitude 22°, was only visible on the 24th.
No. 48. — A faculic disturbance was seen coming round the south-eastern limb on December 24th, and on the 25th was found to be connected with a spot nine thousand miles in diameter, which was last seen by the writer on January- 2nd.
No. 49. — ^Two pores, only observed on December 31st, separated by some fifty thousand miles.
DAY OF DECEMBER, 1914.
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K! JO JO « .» (1 70
90 100 110 129 130 ItO ISO 160 170 180 l90 »0 ZO SO UO W> ISO !W SO 3S0 29D yW JIO 170 130 J«0 iSO ItO
Its greatest nd miles.
45. — A gro>_ und the liml: , with thrc -ip the groi: our tliousai spot eleven il vhen it appe: iance.
46.— A fine the 12th, ^ :)usand miles ifty-six thor- e Umb on -
n. — A spor 18th a littU
:h, on the 3rd, was seventy'- two
t seen as two considerable spots . he 3rd. The eastern spot was the
;r umbrae. Some pores helped to .Sth. The length of the group was
les, and the greatest diameter iixnd miles. It was last seen on the ■ s a group of five pores in a facuUc
which wa^ found to have broken d of two considerable spots about lameter, with some pores between miles in length. It was last seen
h.
jusand miles in diameter, first seen n the limb. Two pores followed it
Faculic disturbances were near the north-western limb on December 1st (215°, 19° N.), Sth (160°, 16° N.), 14th, 24th (274°, 19° N.), 26th, 27th (216°, 20° N., and 204°, 18° N.), and 29th ; north-east on December 1st (75°, 24° N.), 16th, 27th (86°, 13° N.), and 31st; south-west on December 5th, 16th (21°, 25° S.), 20th (320°, 15° S.), and 29th ; south-east on December Sth (in which No. 46 afterwards developed), 23rd, 27th (south of No. 48, and 96°, 27° S.), and 29th (52°, 14° S.).
Our chart is constructed from the joint observations of Messrs. John McHarg, A. A. Buss, and the writer.
A second chart is also appended, showng the distribution of the whole of the spot disturbances of the past year. As compared with pre\'ious year-charts, it will be noticed that the spots, as a whole, are much farther from the Equator, are more numerous than in the three previous years, and are more evenly distributed.
D^ IBUTION OF SPOT DISTURBANCES DURING 1914.
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>«^;:pr .:W
THE AMATEUR IN ASTRONOMY.
By W. F. DENNING, F.R.A.S. {Continued from page 11.)
In cases where affluent amateurs have not per- sonally undertaken researches, they have provided the opportunity for professional men, and America furnishes some prominent examples, among which we may instance the great observatories of Yerkes and Lick.
Of course, there are certain investigations which are far more fittingly conducted at well-equipped observatories. The determination of star positions and a great universal work like that of the astro- graphic catalogue are far beyond the capacities of ordinary amateur effort.
There is an idea that all the objects discoverable by small telescopes are now known, and that the great instruments recently erected must be left to grapple with the miniature orbs remaining unknown. This is only partly true. The brighter minor planets have been found, the more prominent double stars, variable stars, the brighter nebulae, have all been detected and catalogued. But in regard to certain other objects of an inconstant character the case is entirely different. I refer to solar phenomena, to new stars, to meteors and aurorae. There are constantly recurring supplies of these, easily observable, and often awaiting detection by the acute and vigilant observer, be he amateur or professional.
On walking out into my garden a few nights ago, to do a little observing work on a beautifully starlit sky, I hesitated a moment in contemplation of the vast conclave above ; and I could not help thinking what a vast amount of useful observation there remained still to be done by systematic effort. Ordinary amateurs, with good telescopes and prac- tised eyes, might accomplish it. Double stars might be measured or new ones searched for, Mars and Saturn examined and drawings made, sweeps made for new nebulae or new comets, the position of visible comets determined ; without telescopic aid the light of variable stars might be estimated, new variables looked for, the heavens scrutinised for new stars, a watch maintained for meteors, and their paths recorded. These form a few items of the work suggested by the inviting firmament : it has been inadequately performed
in the past ; let it be more thoroughly effected in the future. Let amateurs realise that their role is still a most important one, and that splendid work ever awaits able and well-directed effort.
They should certainly not be discouraged by the supposition that they are now too heavily handi- capped to collect any valuable contributions to the science.
I have often thought that there is not a wide difference between the amateur and the professional. In some cases the distinction is certainly a very trifling one. In one sense assuredly, men like J. F. W. Herschel, R. A. Proctor, W. R. Dawes, and C. Flammarion can hardly be regarded as merely amateur astronomers, but it is obvious that in every case the amateur studies the stars out of pure love for the subject. He admires the wonderful pictures the heavens afford, and marvels at the mysteries involved. There is a sublimity and infinity about astronomy which attract the intellectual mind and induce a feeling of reverence and awe. The peer and the plebeian alike are tempted to " lift up their eyes on high," for there is often found identity of feeling amid wide differences in social status in the great brotherhood of humanity. With regard to the professional, he ostensibly devotes himself to the study, not exactly as a way to wealth, but as a means of earning a livelihood. In very many cases, however, this is not all. Many pro- fessionals work at astronomy con amove. They have selected it because they have a deep regard for it. There must be really very few professional astro- nomers but who feel an intense interest in their subject, and whose labours are prompted by inclination. Abundant evidence of this has been afforded by them in recent years, for they have performed heavy work of honorary character quite outside their official duties. For instance, the British Astronomical Association, which is understood to provide encouragement for and useful cooperation amongst tyros and amateurs, has been assisted in most material degree by professional men who, after their heavy routine work, have freely devoted much time and attention to the assistance of mere beginners in the science.
THE ZOOLOGICAL SOCIETY.
The registered additions to tlie Zoological Society's Menagerie during tlie month of December were fifty-two in number. Of these twenty-seven were acquired by presentation, eighteen were received on deposit, three in exchange, and four were born in the Gardens. The following, which are new to
the Collection, may be specially mentioned : A Peter's Dwarf-Mongoose (Hclogalc undulata), from Wangi, Tana- land, E. Africa, deposited; and a Golden-eared Honey-eater iPtilotis cltrysotis), from New Guinea, presented by Alfred Ezra, F.Z.S.
44
February. 1915.
KNOWLEDGE.
45
From a pho:os*aph hy I <V','
Figure 28. Mr.s. Fiammetta Wilson.
/•■-.;;/ a photngraph hy J K instil Sr Sitiis.
Figure 30. The Rev. T. E. R. Phillips, M..\.. F.R..-\.S.
/■rout a p/uitti^'a/' :
Figure 29. WiUiam Lassell.
Figure 31. G. F. Chambers, J. P., F.R.A.S.
46
KNOWLEDGE.
February, 1915.
^
..-.i*'
Figure 32.
The right half of the lower jaw of a Beaver, showing the molar teeth standing high oat of their sockets, which are above that of the incisor.
#
Figure 3i. The left half of the lower jaw of a Beaver for comparison with Figure 34.
I 1..1 Kt j4.
The left half of the lower jaw ot a Wombat, showing the molar teeth sunk very deeph- in their sockets, which curve, while the first actually runs under that of the incisor.
THE TEETH OF THE WOMBAT AND THE BEAVER.
It is everyday knowledge to naturalists that, among the marsupials of Australia, we have types which correspond wth the various higher orders of old-world mammals, and present features analogous to theirs, owing to their getting their living in the same of several ways. For instance, the Tasmanian wolf is carnivorous, the kangaroos are herbi- vorous, and the wombat gnaws like a rodent. The matter which concerns us here is connected with the teeth of the last-mentioned animal. In Figures 32 to 34 the lower jaw of a wombat is compared with that of a true rodent, the beaver. The lower incisor of the latter is exceptionally large, but the corresponding tooth in the wombat is also very well developed (see Figure 34). It will be seen that it is necessary to find room for the large incisors in both cases. In the beaver, as shown in Figures 32 and 33, the molar teeth, which are the only ones developed in addition to the
incisors, stand high out of the jaw, and their sockets are above that of the great incisor. In the wombat, in the anterior part of the jaw at any rate, there is just the same need for accommodating the incisor socket; but it wll be seen that the surfaces of the molar teeth in this animal project but little above the jaw, and it is by the curving of the molar teeth that the difficulty has been got over, the sockets ending below the level of the incisor, and in the case of the first grinding tooth coming directly underneath it. The interest lies in the fact that the same necessity has been met in two very different ways in a rodent and in a marsupial. The specimens from which Figures 32 and 34 were taken are exhibited at the Eton College Museum, to which Sir Edmund Loder kindly presented the beaver jaw.
W. M. W.
THE FACE OF THE SKY FOR MARCH.
By A. C. D. CROMMELIN, B.A., D.Sc, F.R.A.S.
Table 10.
|
Date. |
Sun. R.A. Dec. |
Moon. R.A. Dec. |
Mercury. R.A. Dec. |
Venus. R.A. Dec. |
Saturn. R.A. Dec. |
Neptune. R.A. Dec. |
|
Greenwich Noon. Mar. 3 |
h. m. 0 2249*3 S. 7*5 23 7-9 5-6 23 26"3 3 6 23 44*7 S. 1*7 0 2 "9 N. 0*3 0 2I"I N. 2*3 |
h. m. 0 II 21*2 N. 1*9 15 56*7 S. 25-8 20 56 '6 S. 18*7 0 491 >J- 9'5 4 51-8 N.27*5 9 18*7 N.i6*5 |
b. m. 0 21 42*7 S. ll'O 21 40'5 12*4 21 48*1 i2"g 22 2'3 12*6 22 22*5 11*6 22 45'5 S. 10*0 |
h. m. 0 19 48-4 S.i9'3 20 11 '9 i8"6 =0 35*5 17*6 20 sS-g i6's 21 22*3 15*1 21 45-4 S.i3*6 |
h. m. 0 5 40*0 N.22-4 5 4o'3 22*4 5 40-8 22*5 5 41 '5 22'5 5 42-3 22;5 5 43 4 N.22 5 |
h. m. 0 8 0-2 N.ao*2 7 59*8 20*2 7 59 '5 20 '2 7 59-2 20'3 7 59*0 20-3 7 58*8 N.20-3 |
|
,, 27 |
||||||
T.\BLE 11.
|
Date. |
Greenwich Noon. |
Midnight Moon. P |
|
Sun. PEL |
||
|
0 00 — 2I'8 —7*1 21*0 23-0 7*3 315-1 240 7-2 2492 24-8 7'i 183*3 25-5 7'0 117*4 — 26"q — 6'8 51*5 |
+22*1 + 9*4 -i6'4 — 21*5 - 4-8 + i7'7 |
|
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 heUo-(planeto-)graphical latitude and longitude of the
centre of the disc. For the future the data for the Moon and Planets in the Second Table will be 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 at its maximum rate, crossing the Equator 21'' 4'^ SI"" e. Its semi - diameter diminishes from 16' 10" to 15' 2". Sunrise changes from 6" 50" to 5" 42" ; sunset from 5" 36" to 6" 28"°.
Penumbral Eclipse of Moon. — There vi-ill be a Penumbral Eclipse of the Moon on March 1st about 7*" e.
A slight smokiness will be discernible on the Northern portion of the disc.
Mercury is a morning star in W. elongation, 27° 43 W. of Sun on 20th. Semi-diameter diminishes from 5" to 3". Illumination increases from I to 5.
Venus is a morning star. Illumination increases from 3 to iV- Semi-diameter diminishes from 10" to 8".
The Moon.— Full l" 6" 33" e. Last quarter 8'' O" 28" e. New 15* 7" 42" e. First quarter 23^ lO" 48" e. Full 31* 5" 38° m. Perigee 5" 3'" m. Apogee ai* l"- m, semi - diameter 16' 19", 14' 46" respectively. Maximum hbrations 7* 7" N., 12* 5° W., 20* 7° S., 27* 7° E. The letters indicate the region of the Moon's limb brought into view by libration. E., W. are with reference to our sky, not as they would appear to an observer on the Moon (see Table 12).
Mars is invisible, having been in conjunction with the Sun on Dec. 24tb.
Jupiter was in conjunction with the Sun on Feb. 24th, and is therefore practically invisible this month.
Saturn is between Taurus and Gemini. In perihelion Feb. 21st. Stationary Feb. 26th. In quadrature Mar. 17th. Polar semi-diameter 9". Major axis of ring 42", minor 19". Angle P-5°-7.
47
48
KNOWLEDGE.
Table 12. Occultations of Stars by the Moon visible at Greenwich.
February, 1915.
|
Star's Name. |
Magnitude. |
Disappearance. |
Reappearance. |
|||
|
Date. |
Time. |
Angle from N. to E. |
Time. |
Angle from N. to E. |
||
|
1915. |
h. m. |
0 |
h. m. |
jj |
||
|
Mar. 4 |
75 Virginis |
57 |
— |
— |
10 17 e |
237 |
|
>' 5 |
WZC 871 |
7-0 |
— |
— |
I 55 « |
345 |
|
,, 8 |
BAG 5603 |
60 |
3 3S '" |
140 |
4 37 '" |
245 |
|
,, 10 |
WZC 1243 |
7-4 |
— |
5 15 '« |
229 |
|
|
„ 24 |
39 Geminorum |
6-1 |
5 Of |
S5 |
6 20 1; |
296 |
|
„ 24 |
40 Geminorum |
6-3 |
5 29 c |
116 |
6 49 « |
267 |
|
., 25 |
52 Geminorum ... |
60 |
I 46 m |
loS |
2 ^8« |
284 |
|
„ 25 |
\VZC49S |
6-9 |
I 56 '« |
162 |
— |
— |
|
„ 26 |
fi^ Cancri |
5-4 |
2 5 m |
■73 |
2 30 m |
230 |
|
„ 26 |
BAG 2991 |
6-1 |
8 Se |
106 |
9 22 « |
312 |
|
,, 27 |
WZC 618 |
71 |
3 0 m |
177 |
— |
— |
|
,, 27 |
II Leonis ... |
6-6 |
5 23 e |
86 |
6 24 e |
327 |
|
,, 29 |
76 Leonis |
60 |
5 36 « |
151 |
6 26 e |
269 |
|
„ 30 |
BAC4119 |
6-6 |
7 39 e |
153 |
8 33 « |
275 |
From New Moon to Full disappearances occur at the Dark Limb, from Full to New reappearances.
Eastern elongations of Tethys (every 4th given) S** y*" -7 m, 10^ S^-g?, ISMO^-a m, 25*' ll''-5 e; of Dione (every 3rd given) S-" 10'^ -1 m, le*" 3"" -3 e, 24"* S''-4 e ; of Rhea (every 2nd given) T^ 11'' -1 iit, le'' Noon, 25^ l^-O e.
For Titan and Japetus E., W. stand for East and West elongations, I. for Inferior (North) conjunction, S. for Superior (South) conjunction. Titan 4'* e'' -8 m S., S"* 9^ -1 m E., 12'' Qi^ -1 m I., le'i 6*' -3 m W., 20<' 6^ -0 m S., 24^ 8'' -5 m E., 28'' 8''-5 m I.; Japetus 1'' 2^ m W., 20'' 1^ m S.
Uranus is invisible. In conjunction with Sun on February 1st.
Neptune was in opposition January 20th, diameter 2".
Double Stars and Clusters. — The tables of these, given three years ago, are again available, and readers are referred to the corresponding tnonth of three years ago.
Variable Stars. — Stars reaching their maxima in or near March, 1915, are included. The lists in recent months may also be consulted.
Meteor Showers (from Mr. Denning's List) : —
|
Date. |
Radiant. |
Remarks. |
|
R.A. 1 Dec. |
||
|
Mar. 1-4 „ 1-14 ... „ 18 ... „ 24 „ 27 Mar.— May ... |
166 + 4 17s + 10 316 + 76 161 + 58 229 + 32 263 + 62 |
Slow, bright. Slow. Slow, bright. Swift. Swift, small. Rather swift. |
Table 13. Long-period Variable Stars.
|
Star. |
Right Ascension. |
Declination. |
Magnitudes. |
Period. |
Date of Maximum. |
|
U Persei W Andromedae T Camelopardi R Aurigae R Ursae Maj. T Ursae Maj |
h. m. s. 1 53 57 2 12 II 4 31 4S 5 10 25 10 38 42 12 32 33 |
+54 24 +43 55 +65 59 +53 30 + 69 13 + 59 57 |
70 to 10- 9 7-0 to 13-8 7-0 10 13-5 6-5 to 13-3 5-9 to 13-1 5-5 to I2'7 |
d. 317 395 370 448 299 257 |
1915 — Feb. 23 ,, Feb. 9 ,, Apr. 19 ,, Apr. 4 „ Feb. 27 Jan. 28 |
Night Minima of Algol I'' 7" -26, 4" 4" -Oc, Id" 3" •4m, 19" O'' -1 m, 21'' 8" ■ Principal Minima of (3 Lyrae March l" b^e, 14" A^e, 27" 3"" c.
9 e, 24" 5" -7 e. Period 2" 20'" 48'° -9. Period 12" 21" 47"-5.
REGENERATION.
The regeneration of " arms " in starfish, claws in lobsters, and tails in lizards exemplifies the replacement of lost parts in animals ; and, although we cannot get a new lizard from an old tail, or a new lobster from a discarded claw, yet it is possible to grow a new starfish from a detached arm. In the vegetable kingdom this kind of regeneration is more common, and is put to practical uses. The making of a cutting may not seem so striking as the growing of a new starfish, for roots only have to be formed (see Figure 40), and this underground ; but many leaves can
produce, not one young plant, but quite a number. This is the case in Bryophvllum, and in Figures 35 and 36 a leaf is shown which has been lying on the moist ground for a little time. The edges of it are bounded by quite a clump of young plants. Figures 36 to 39 show other leaves, which will reproduce the whole plant, and the begonia is commonly propagated by gardeners in this way. Figures 40 to 49 also bear on this question, and it is possible to
obtain a geranium from a leaf-stalk.
W. M. W.
February, 1915.
KNOWLEDGE.
49
Figure 35. Seen from abo\e. Figure 36. Side view.
Two Views of a Leaf of Bryophyllum. showing the young plants which it produces when broken off and laid on the ground.
Figure 37.
A Saintpaulia Leaf with roots springing from the petiole.
Figure 38.
Leaves of Tolnicia Menziesii sending out buds where the stalk joins the blade.
Figure 39. A Begonia Leaf producing new plants.
Figure 40.
Pieces of the thick stem of an Aroid \Dicffcnbachia Batisei) used as cuttings, and sending out roots and shoots.
50
KNOWLEDGE.
February, 1915.
Figure 43.
FiGURK 41. .\ Leaf
of Peperomia which has
sent out roots from its
stalk.
Figure 42. A Pepero- mia Leaf that has rooted and produced a number of shoots.
Figure 44.
Figure 45.
Figure 47.
Figure 46.
Figures 4J to 47 represent the succulent leaves of such plants as Kleimia and Echeveria sending out
roots and actintr as nurses to buds at their bases.
Figure 48. A Pelargonium Cutting. Only a few- leaves are allowed to remain on the shoot, so that it may not lose all its water supply.
Figure 49. A Carnation Layer. It has sent
out roots, and is still connected with the parent
plant.
NOTES.
ASTRONOMY.
By A. C. D. Cro-M.melin, B.A., D.Sc, F.R.A.S.
THE ORBIT OF DELTA ORIONIS— This star, the right-hand member of the belt, lying alxnost exactly on the celestial equator, is an interesting spectroscopic binary. A discussion of its orbit, by Frank C. Jordan, appears in " Publications of Allegheny Observatory'," Volume III, part 15. He uses both his own and earlier photographs of the spectrum, and thus has obser\-ations available extendiirg over ten years. The spectrum is of Type Bl (helium type). No secondary spectrum can be traced ; so evidently there is great disparity' in the light-giving power of the components.
The most probable value of the period is 5 -73257 days ; the eccentricity, 0-09 ; the orbital velocity, 100 kilometres per second ; longitude of periastron, 5° in 1902, 20° in 1910 ; the recessional velocity,' of the centre of gravity, 23 kilo- metres per second in 1902, 15 kilometres in 1910 ; a sin i =7,850,000 Idlometres.
Also, if »«i, in^ denote the masses of primar>' and second- arj' stars (the Sun being unity),
m.? sin^ i
r^—. -,3 = 0-588.
The change in the longitude of periastron is doubtful, as there is considerable uncertaints' in the determination ; it is, however, in accord with what tidal action would lead us to expect. The change in the rate of recession of the e.g. may only arise from the different personality of the obser\'ers ; it may, on the other hand, indicate revolution round a third member of the system, such as is beheved to take place in the case of Algol.
There are many spectroscopic binaries for which our ignorance of the value of i is complete : this is not the case with Delta Orionis, for Mr. Joel Stebbins found some years ago, with the aid of his sensitive selenium photometer, that it is an Algol variable, though the change of Ught is too small to detect by ordinary methods. Hence we see the system nearly edgewise, and a partial eclipse occurs in each revolution.
If we assume for the companion a mass half that of the primary, and conjecture for the radii of the two one and a half and one milUon kilometres, also taking the amount echpsed as one-quarter of the diameter of the primary, i comes out 86°. It is unnecessary to know it very accurately, since the sine of an angle near 90° changes slowlj'. Under these assumptions the masses come out 10|, 5s, that of the Sun being 1.
If we assume equal masses, and take i=83°, the mass of each is two and a half times the Sun's. The total mass of the system probably hes between ten and twenty' times the Sun's. From the minuteness of the star's proper motion it is beheved to be very distant ; hence the luminositv of the primarj' is, presumably, very great in proportion to its mass ; in other words, its density is small, and its radius may not improbably be considerably greater than that assumed above. This would diminish the value of sin ;, but not enough to seriously affect the masses.
This star is one of those in whose spectra the H and K hnes of calcium do not share in the periodic displacement. No ver\' satisfactory explanation of this peculiarity has been arrived at, but it is supposed to indicate an extended calcium cloud enveloping the system. Jlr. Jordan finds 18-5 kilometres per second as the velocity of this calcium cloud away from the Sun. This is 3-5 kilometres greater than the velocity of the e.g., but the difference is not large enough to lay great stress upon. He notes that the Sun's own speed is about eighteen kilometres per second away from the star ; hence the calcium cloud is practically at rest
with reference to the sidereal system — at least as regards the radial component. This is in accord \rith the fact that the stars of early spectral type have in general small velocities. It will be of great interest to follow this star fairly continuously, both with the spectroscope and photo- meter, to ascertain whether the motion of the periascion and change in the speed of the e.g. are verified. It is quite likely that an analysis of the hght-curve during echpse would give further information about the diameters, but I have not at present access to the details.
MOULTON AND CHAMBERLIN'S PLANETESI.MAL HYPOTHESIS. — Mr. T. C. Chamberlin gives an interesting exposition of this hypothesis in Scientia for October. The theory does not deal with the birth of the Sun, which is supposed to have formerly existed as a soUtary orb. Another Sun is supposed to have passed fairlj' near it (according to the authors, a distance of a hundred milhon miles, or even more, would not be too great to produce the effects they postulate : approaches within this distance would be vastly more frequent than actual coUisions). The result is tidal distortion of each star, protuberances being raised on opposite sides of them. These are supposed to have reached such a height that a large quantity of matter on each side broke off from the parent star and commenced to describe orbits round it, the moment of momentum required for this revolution being derived from the attraction of the other star. This acquirement of extraneous moment of momentum is the leading motive of the theory : " The Sun holds about seven hundred and forty-five out of seven hundred and forty-six parts of the total matter of the solar system, wliile it only carries about two per cent, of its moment of momentum. This leads to the conviction that a new agency came in, after the original formation of the Sun, and gave to a very small fraction of the solar matter, after it had been drawn out from the Sun, a special endowment of momentum." The two streams of matter would form a double spiral, of a form that we meet with in numerous nebulae. The argument from analogy is used by the authors to support their theory Another argument, not used by them, seems to me to be the constitution of meteors, which frequently contain a large quantity- of hydrogen. This would be explained if they had once formed part of the crust of the Sun, on the hypothesis that this crust had already solidified before the approach of the other Sun, but was then disrupted by tidal action.
I shall continue this note next month.
BOTANY.
By Professor F. Cavers, D.Sc, F.L.S.
EFFECTS OF ELECTRIC DISCHARGE ON PLANTS. — Many experiments have been made during recent years in which plants, otherwise under normal conditions, have been subjected to an electric discharge from an overhead system of wires during a considerable portion of their growing period, and, as a result, acceleration of growth and increase in yield have been invariably reported. Since this treatment must considerably alter many factors in the plant habitat, and in the plant's reaction to this habitat, it is difficult to ascribe the effect, apparently due to the electric discharge, to any particular physiological cause. Priestley, who has taken a prominent part in this line of investigation, records in a recent paper, in collaboration wth Knight {Annals of Botany, Volume XXVIII), some of the first attempts to analyse the efiect of the discharge upon the plant by investigating under laboratory con- ditions the effect produced by such discharge upon one ph5'siological function, namely, respiration. Experiments were made \\ith small direct currents at a relatively low
51
52
KNOWLEDGE.
February, 1915.
voltage and with electric discharge at liigh tensions. The results show that direct currents have no effect on the respiration of peas other than that due to accompanying changes of temperature ; but the proportion of these cur- rents actually traversing the peas was probably very small, the majority being taken by the water films of the seeds. Overhead discharge of low density has no effect on respir- ation ; but with liigher currents a definite increase of the carbon dioxide output was observed, this increase being wholly attributable to the rise of temperature caused by the discharge. In the field, where the currents are too small to produce any appreciable rise in temperature, electrification will have no effect on respiration, and an explanation of the acceleration of growth must be sought in other functions of the plant. The gaseous products of the discharge in air have no effect on germinating peas, but are injurious to young seedlings. These results do not, of course, mean that the acceleration is inexplicable, for one result of electrification may be increased transpiration, which alone would account for a more rapid attainment of maturity by the plant ; while various observers have found that electrification produces increased activity of con- structive metabolism — the processes of building up food materials in the plants.
STATISTICAL METHODS IN PLANT GEOGRAPHY. — For many years the Swiss botanist Jaccard has been investigating in great detail the distribution of plants in certain definite areas in alpine meadows, and has obtained some interesting results, which appear likely to be of general application. His latest paper (Rev. gin. Bot., Volume XXVI) deals with the vegetation of some alpine gravel areas, but a fuller account of his earlier results is given in an English paper (New Phytologist, Volume XI). Having made a census of the flowering plants growing in the areas to be compared — similarly situated localities of about the same area in different parts of the Alps — he applies to the analysis of his results what he called the " coefficient of community," that is, the percentage ratio between the number of species common to two district and the total number of species in the two districts. For alpine meadows he found that (1) the value of this coefficient does not depend on floral richness, but upon the ecological characters of the areas studied ; (2) the alpine flora is extremely diverse in floristic composition ; (3) the rare species are most numerous and the common species least numerous [This does not apply to individuals, but to species] ; (4) the coefficient is usually higher for contiguous than for distant areas. He also uses what he terms the " generic coefficient," that is, percentage ratio between number of genera and number of species, and finds that this coefficient varies inversely with the variety of ecological conditions in the areas compared. For instance, in alpine areas its value increases with altitude ; while in the Belgian sand-dunes (from data given by Massart) it is greatest (100) under the excessive and narrow ecological limits of the moving dunes, and least (73) under the more varied conditions of the pannes (salt marshes). From his analyses Jaccard draws the following general conclusions. The distribution of plants, at any rate in the alpine zone, is a resultant of the combined action of three kinds of factors : ecological biological (degree of adaptation), and sociological (com- petition between species). The action of these factors has resulted in two kinds of selection : an eliminative selection of species and a distributive selection, determining the number of individuals and the nature of associated species. Readers interested in the subject should consult the New Phytologist paper for details of Jaccard 's interesting investigations.
A DARK-GROUND ILLUMINATION STUDY OF PLANT CELLS. — Until about ten years ago the method of dark-ground illumination with the microscope was regarded simply as a means of exhibiting objects with pretty and striking effect, and even now much less use has been made of the method in the investigation of the plant
cell than might have been anticipated. In a recent paper Price (Annals of Botany, Volume XXVIII) gives the results of his examination of various plant cells, made with the object of seeing whether, by this method, more facts might be obtained concerning the colloid structure of the living and the dead cell and the reactions of the colloid. He gives a brief account of the necessary procedure, suitable objects for study, and so on, and the paper will be found very useful by others wishing to examine plant cells by this method. The objects used were chiefly filamentous algae, spores, and hairs ; and in his summary the author points out that the method often reveals new structural features, and is useful in establishing the presence of minute particles, which are difficult to see or are unresolved in direct illumination, though the method is restricted in application, owing to the difficulty of selecting suitable material for examination. It is generally recognised that protoplasm is a colloidal complex existing both in the hydrosol and the hydrogel state, a hydrosol being a colloidal solution — differing from an ordinary solution essentially in consisting of particles suspended in a continuous medium — while a " gel " is a sponge-like body in which the con- tinuous phase encloses the other phase in a mesh of cavities. To a certain extent, these states are spontaneously reversible. The process of germination of certain fungus spores showed the gradual conversion of the gel - contents of the spore into a hydrosol on absorption of water, while later on a formation of a gel may occur again. The nucleus and chloroplast are evidently specialised parts of the plasma, with a hydrogel structure ; particles and vesicular bodies (" sap particles "), usually present in the cell-sap and showing a continuous Brownian movement, were found to increase in number with decreasing vitality of the cell. The effects of plasmolysis were studied with different reagents, and it was found possible to distinguish an outer layer with much finer structure than the rest of the proto- plasm, this layer being apparently the part concerned in the formation of the fine fibrils, which often connect the plasmolysed protoplast with the wall of the cell. A similar layer was also recognised on the inside of the protoplast against the vacuole. The action of fixing and coagulating agents was studied, and it was found that during fi.xation a change to an opalescent hydrogel takes place, the rate of formation and the structure of the gel differing in different plant material and with different agents.
CHEMISTRY.
By C. AiNSWoRTH MircHELL, B.A. (Oxon), F.I.C.
GERMANY'S MOTOR FUEL —Three recent issues of the Zeitschrift fur angewandte Cliemie which have recently come to hand by way of a neutral country show the straits to which Germany has already arrived from the shortage of petrol.
According to Dr. Hempel (page 521), Germany, in 1913, produced 179,800 tons of petrol and 160,000 tons of benzene (benzol), nearly a third of which was exported to France, while in the year 1912-13 the country's production of alcohol — mainly from potato starch — reached 3,753,265 hectolitres. Alcohol thus appears to be the natural sub- stitute for petrol, and Dr. Hempel states that, by order of the Kaiser, all motor-cars in Berlin have been adapted to use alcohol as well as petrol.
The relative heats of combustion of the various possible fuels are as follows : Petrol, 9500 to 10,500 ; pure benzene, 10,260 ; commercial benzene (benzol), 9550 to 10,000 ; pure alcohol, 7402 ; ninety-five per cent, alcohol, 5875 ; and pure naphthalene, 9628-3 calories per kilogramme.
In practice a mixture of four parts of ninety-five per cent, alcohol with one part of benzene, containing two hundred grammes of naphthalene per htre, gave the same results as ordinary petrol ; whereas the use of alcohol by itself tended to rust the tubes of the carburettor.
February, 1915.
KNOWLEDGE.
53
Dr. Dieterich (page 543) describes various mixtures of alcohol with benzene, commercial acetone, and petroleum oil as being suitable for motor engines, but points out that in each case preliminary' heating of the carburettor and reduction of the supply of air are necessary.
Dr. Mohr (page 558) discusses the suitability of the various mixtures suggested by Dr. Hempel and Dr. Dieterich. In his experience only the simplest mixtures of alcohol with hydrocarbons have given satisfactory results. Thus he has found suitable for the purpose a mixture of alcohol and benzene in equal parts ; or of alcohol, one half ; benzene, a quarter ; and petrol, a quarter. Naphthalene is an unsuitable ingredient owing to its forming crystalline deposits. Attempts have been made to use alcohol con- taining about one half per cent, of ammonium perchlorate, but these were unfavourable owing to the chlorine compounds formed in the explosion attacking the metal. All three chemists express their confidence that Germany will be able to produce sufficient alcohol for their motor engines, and that all mechanical difficulties can be over- come. They mention that about a dozen firms are now manufacturing carburettors specially adapted for burning alcohol and mixtures of alcohol and benzene. The addition of a small amount of motor oil is suggested as a means of preventing rusting of the tubes by the alcohol.
PROPERTIES OF XAPHTHENIC ACIDS.— The waste alkaline lyes from the refining of petroleum oils contain a large proportion of compounds which are known as " naphthenic acids." They can readily be separated by treating the lyes with a mineral acid, and, owing to the in- creasing scarcity of coconut and palm oils, are of grovring importance for the manufacture of soaps, especially for such as -irill give a lather \\ith salt water. Unfortunately, their use in this direction is restricted by their unpleasant odour, and attempts are being made in many directions to obviate this drawback.
In the last issue of Les Mati&res Grasses (1914, VII, 4115), M. E. Schmitz gives an account of his systematic experiments upon the deodorisation of the acids. He found that, by repeatedly treating them \v'ith dilute sodium carbonate solution, an insoluble compound of phenolic character, which showed the characteristic odour in an intensified degree, could be separated, while the final product had only a very faint odour. The dark, insoluble " oil " gave an intense bluish-green colour with copper salts, and could be used as the basis of a lacquer for wood. Attempts to deodorise the naphthenic acids by hj-drogen were unsuccess- ful, but treatment with ozone for about tivo hours reduced the odour to some extent, and could be used as a practical process after removal of the evil-smelling phenolic sub- stances by means of sodium carbonate as described.
GEOGRAPHY.
By A. Scott, M.A., B.Sc.
MAPS AND PHYSICAL GEOGRAPHY.— In the
Geographical Journal for January Mr. Alan Ogilvie discusses the utihty of our available maps from the point of view of the physical geographer, and makes a number of suggestions regarding the ways in which they might be made more useful. As it has not been found possible, so far, to combine the virtues of the different editions of the Ordnance Survey maps, all editions should be kept on sale. Similarly, atlases of land-form types, on one-inch and six-inch scales, would be of great service to teachers. The chief defect of geological maps, from the geographer's point of view, is that it is often impossible for the non-geologist to determine from such maps the hthology of the district, and this can only be remedied by the preparation of lithological maps. Other things which might be indicated on these maps are the porosity and comparative resistance of the various strata. In the investigation of land forms, much useful information could be obtained from maps showing what processes have been most effective, and also the stage of maturity at which
the various features have arrived. In connection with water supply, it is suggested that not only might the different types be cartographically indicated, but also the variation of headwaters and river volumes. Other pheno- mena which might lend themselves to more accurate map- ping than they have hitherto received are meteorological conditions, vegetation, and oceanographical and soil-survey data.
GEOGRAPHY AND STRATEGY.— There are two principal ways in which geographical conditions affect strategy : one with regard to lines of advance and the other with regard to obstacles. The former are determined by the occurrence of level country or of " defiles," such as river valleys. According to Hilaire Belloc [Geographical Journal, January, 1915), obstacles are of five types : rivers, including canals, forests, hill countrj'. deserts, and marshes. Rivers are never permanent obstacles, though they may have a great tactical value temporarily, such as the Ourcq had during von Kluck's retirement. Forests are serious obstacles unless there are numerous defiles, an example in the present war being the Forest of Argonne. HUls vary in importance, and at one period those along the Aisne proved invaluable to the German Army. As campaigns have seldom been carried out in deserts, there are few data from which to deduce the value of such country. IMarshes provide the greatest obstacle of all, as it is practically impossible to entrench in them. This has been well shown by the campaign in the Yser district.
GEOLOGY.
By G. W. Tyrrell, A.R.C.Sc, F.G.S
PERMO-CARBONIFEROUS BRECCIA OF ENGLISH
INIIDLANDS. — The chief exposures of this deposit occur near Birmingham. It consists of sandstones and marls, with occasional sheets of very angular breccia, which is formed of blocks of volcanic rocks, grits, slates, and limestones identical with rocks from the Welsh border. This puzzling deposit has been variously ascribed to volcanic, glacial, or lacustrine agencies ; but H. T. Ferrar, in a paper read before the British Association, Australia, 1914, shows that it closely resembles certain desert formations. He instances especially the material which partially fills the wadis, or steep-sided gorges, of the folded mountain-chain forming the watershed between the Nile and the Red Sea. " The climate is arid, with occasional heavy thunderstorms, causing temporary- currents, which sweep for%vard all rock material loosened during the prevailing dry climate." This material is very angular and fresh, and, in slipping down the hillsides, or in course of violent water transport, the blocks are frequently scratched, grooved, and even shattered by mutual impact. Huge blocks may be carried as much as a hundred miles down the wadi channels by water, and hence it is not necessary to invoke the agency of ice to explain the occurrence of large blocks in similar deposits. The valley-fill of most wadis in the Eastern Desert of Egj'pt is an unconsolidated breccia, so similar to that of the Permo-Carboniferous in the English Midlands that there can be little doubt that the tivo originated under similar climatic conditions.
METEOROLOGY.
By \ViLLL\M Marriott, F.R.Met.Soc.
THE WEATHER OF FEBRUARY.— February is the last month of winter, and extremely variable in character. There is an old proverb :
" February fill dyke, be it black or be it white ; But, if it be white, it 's the better to like,"
but more recent observations tend to set aside the old proverb. In severe winters the frosts of the two previous months continue, or return with great intensity ; while on several occasions the greatest cold of the year has occurred in this month. It was a very cold month in the
54
KNOWLEDGE.
February, 1915.
vears 1S45, 1S55, 1SS6, and coldest of all in 1S95. It was a very mild month in the years 1850, 1867, 1869, 1872, 1S77, 1903, and 1914.
The average mean temperature at Greenwich for Feb- ruaiy is 39° -5 ; in 1869 it was as high as 45° -6, while in 1895 it was as low as 29°-l. The average maximum tem- perature is 45° -2 ; the highest mean was 51°-8, in 1869, and the lowest 35° -2, in 1895. The average minimum temperature is 34° -3 ; the liighest mean was 39° -7, in 1869, and the lowest 22° -8, in 1895. The absolute highest tem- perature recorded w-as 63°-9, in 1899, on the 10th, and the absolute lowest 6° -9, in 1895, on the 8th. The average number of days on which tlie temperature falls to or below the freezing-point is ten. In 1895 the temperature was continuously below the freezing-point for seven days, from the 5th to the 1 1th.
The average rainfall for the month of February is 1 •52-in. ; the greatest amount was 4-03-in., in 1866, and the least 0-04-in., in 1821. The heaviest fall in one day was 2-89-in., in 1831, on the 7th. The average number of " rain days " {i.e., on which 0-01-in. fell) is 12-4 ; the greatest number of days was twenty-two, in 1893. and the least three, in 1857. Snow falls on the average on three days. The average amount of bright sunshine in the City of London is thirty- one hours, but at Kew Observatory, Richmond, the amount is fifty-six hours.
The average barometric pressure for February is 29-972-in. ; the highest mean was 30-473-in., in 1891, and the lowest mean was 29-499-in., in 1776. There is thus, in the neighbourhood of London, a variation of nearly an inch in the monthly nieans. The highest recorded read- ing in the British Isles was 31-007-in. at Gordon Castle, Banff, in 1808, on the 24th.
From a discussion of the results of the observations in England and Wales during the thirty years 1881-1910 it appears that when the barometric pressure is high in February it is usuallv followed by low pressure in March, and vice versa ; and that a wet Februarj' is usually followed by a dry March.
" If Candlemas Day * be fair and bright, Winter will have another flight ; But if Candlemas Day bring clouds and rain, Winter is gone and won't come again."
* February 2nd.
RELATIVE HUMIDITY IN ENGLAND AND WALES. — At the December meeting of the Royal Meteorological Society Mr. W. F. Stacey read a paper on " The Distribution of Relative Humidity in England and Wales." He had prepared mean monthly and annual maps of relative humidity based on the 9 a.m. dry and wet bulb thermometer obser\-ations made at over ninety stations during the ten years 1901-10. An examination of the maps shows that in winter the air over the interior of the country is more moist than that over the coastal regions ; that the minimum relative humidity occurs earlier in the year in the western parts of the country than in the eastern ; that in summer the air over the interior of the country is drier than that over the coastal regions ; and that the smallest range of humidity is found in the west and the greatest in the interior towards the east. The distribution of temperature is the chief determining factor in the distribution of relative humidity ; while sea influence, the direction and character of prevailing winds, the configuration of the country, all have important effects on temperature, and therefore on relative humidity.
MICROSCOPY.
By J. E. Barnard, F.R.M.S.
THE MICROSCOPE AND THE WAR.— That there is any connection between the microscope and the present disastrous European War is not immediately apparent. A little deliberation, however, will show that both the use and the production of microscopes commercially are seriously affected. If we consider the matter from the point of
view of production, it is quite clear that the number of instruments available at the present moment is not so great as formerly. A very large number were previously imported from the Continent — principally from German^' — and these are not now obtainable. On the other hand, the use of the instrument has been restricted, so that the demand in general is not so great. British manufacturers have no doubt, to some extent at least, stepped into the breach, and are producing to the utmost of their capacity. This, however, does not mean very much, as nearly all manu- facturing opticians are fully occupied in making optical instruments of various sorts for Ann}- purposes. In some respects the position of the microscope industry is analogous to the anilme dye trade. The microscope in its earlier days was almost entirely a British production, whereas it has, to a large extent, especially on its optical side, passed into the hands of Continental makers. If we read through the earlier numbers of The Journal of the Royal Microscopical Society, it is evident that about thirtj^ to forty years ago, when the microscope was in course of development, British makers were in the very front rank. The influence of their design and method of construction is still largely felt ; in fact, it is not too much to say that at the present time, if a micro- scope of the very finest construction is wanted, it is still possible, and perhaps even advisable, to get one of British manufacture. One of the features of the Continental instrument has been its simplicity ; and in this respect there is something to be said for it ; but in evol\-ing such a type. Continental makers have striven more for cheapness than to provide an instrument that is thoroughly efficient. If we take the outstanding characteristic, for instance, of the Continental stand, the horseshoe foot, we are at once con- fronted with a design which has nothing much to recom- mend it ; whereas the British type of tripod foot is in every respect more stable, and a better method of support in whatever position the instrument may be used.
The sub-stage, which is now recognised as of primary importance, the Continental makers have reduced to its simplest proportions, and in some respects have made it almost a useless feature of the instrument owing to the lack of centring adjustment. The British manufacturers have never been behindhand in this particular, and their instru- ments of the better class have been such that one might use them for the most exacting work.
That most of the improvements in microscope design have been of British origin is a matter of common know- ledge, and it is only necessary to consult the earlier Uterature of the subject to realise this. It is hoped, therefore, that British makers will not lose the opportunity that has pre- sented itself, of recovering at least a large part of the trade that they have lost, and that they will set themselves to so deal with the matter that when competition arises again there will be real strength behind it to meet every possible contingenc}'. That the Continental makers, particularly those of Germany, have not relied on cheap labour, but on specialisation and systematic methods of production, is beyond question ; and unless the British makers are pre- pared to launch out and do their part in this direction there is perhaps little hope for them in the future. So far as the optical side is concerned. Continental makers have been very much to the fore. It is no uncommon thing for a microscope of best British design and manufacture to be fitted with objectives of Continental make, and that, not because they are cheaper, but rather because they are better in quality, the price in some cases being substantially higlier than those of British origin. In this respect it is somewhat reassuring to know that at least two British firms are making a feature of apochromatic objectives, and there is little doubt that these will be in eveiy respect equal to those from the Continent. When the apochromatic objective was first brought out there was a very definite distinction between it and the achromatic object which had been in general use up to that time. Even now the difference between the true apochromatic objective and the ordinary objective is a fundamental one, although there are many objectives which do to some extent bridge
February. 1915.
KNOWLEDGE.
the gap. A lens may be ver^- well corrected, in the sense that some are described as semi-apocliromatic, but it does not give it those exact quahties which the apo- chromatic objective should possess. That British makers are able to comply with the conditions is beyond question, and it is to be hoped, now that the Continental supply is stopped, users in this countrv will realise that the production of the best optical firms here is Ukely to be equal in every respect to that of Continental origin.
THE CARE OF A MICROSCOPE.— It is no uncommon thing, particularly in laboratories, to see an ordinar\' duster or some other dirtj' cloth used for cleaning lenses or other optical parts of a microscope. This is a most pernicious habit from every point of \'iew. Nowadays the polish on optical surfaces is of a high order, and anything which tends to destroy this polish interferes \\'ith the per- fection of the image, and causes loss of light. If hnen is used for cleaning purposes, it should be old, and must be thoroughly wEished before use, so that it is cleansed from all dirt and grit. A better method, particularly when working ^\•ith oil-immersion objectives, is to use Japanese rice paper, which is now easily procurable, and is very soft and clean. A small piece of this may be torn off, and the lenses carefully wiped with it and the piece thro^vn away. This will be found less expensive, less troublesome, and more efiective than using iinen or cloth of any description. Any optical parts, even if temporarily out of use, should not be left uncovered on the working bench. For this purpose an ordinary glass mav be inverted and placed over the lens, or a small bell jar, purchasable for a few pence, may be used. The brass cases for objectives should always be laid on the bench with both bottom and top inverted, so that no dust can enter.
THE QUEKETT MICROSCOPICAL CLUB.— The five hundred and fourth ordinan,- meeting of tlie Quekett Microscopical Club was held on Tuesday, January- 26th, at 20, Hanover Square, W. ; the President, Professor Arthur Dendy, D.Sc, F.R.S., in the chair. Three gentlemen were elected members, and four others were nominated for election. The names of officers nominated by the Committee for the ensuing year were read, being sub- stantially the same as at present, with Professor Dendy again as President. The members proposed the names of gentlemen to serve on the Committee to fill the vacancies caused by the retirement of senior members. The ballot will take place at the annual meeting.
Vice-President Professor E. A. Minchin, M..\., F.R.S., then gave a paper, " Notes on Flea Anatomy." He said that, although the main purpose of his researches was to trace the development of the Trj-panosomes found in the rat flea, ha\'ing with the help of a friend dissected about one thousand seven hundred fleas, it was ine\-itable that an intimate knowledge of the minuter structure should be acquired. He then described the instruments and the methods employed, and gave a full account of the anatomy and histolog3' of the internal organs, comprised under the following heads : (1) Notes on the abdominal nervous system, sho\ring the curious difference between the male and the female ; (2) on the male reproductive system ; (3) on the female reproductive system ; (4) on the stellate muscle- cells of the oesophagus. The lecture was of a most interesting character, especially to the audience to whom it was addressed, appealing particularly to microscopists. It was illustrated by lantern diagrams thrown on the screen, and by a series of beautiful micro-preparations exlubited under microscopes on the table. These slides Professor Minchin has presented to the Club, and they will be added to the cabinet for the future use of members. Professor Dendy made a few appreciative remarks, and proposed a vote of thanks to the lecturer, which was heartily accorded by acclamation.
The next ordinary meeting will take place on Tuesday,
Februarv 23rd, when, after the usual business of the annual meeting. Professor Dendv will deliver the Presidential address, his subject being " The Biological Conception of Individualitv."
T B.
PHOTOGRAPHY.
By Edgar Senior.
THE ELIMINATION OF THE SOLUBLE SALTS .\ND "HYPO" FROM THE GEL.\TINE FILM.— In these days of huny- and scurry there is a growing tendency to give but little attention to the fixing and washing of negatives and prints. With the idea of saving time, they are often imperfectly fixed, and still more often imperfectly washed. Man^' workers appear to lose sight of the fact that it is false economy to withdraw either negatives or prints too soon from the fi.xing bath, as, when properly fixed, they can be freed from soluble silver salts and " hypo " much more rapidly than otherwise would be the case. .\s already pointed out in these columns, it is a good plan to use tvvo fixing baths, the second one ensuring a complete conversion of the silver salts into the soluble variety', which readily diffuse out in the washing water. Of the various processes through which a negative passes it can be said that there are few of greater importance than thorough washing, for unless this be properly done endless trouble will arise in any after treatment that may be found necessary. Then, again, although there are many excellent washers on the market, the amateur often makes use of some domestic utensil, which is quite unfitted and unsuitable for the pur- pose. In any case, whatever kind of appliance be employed for washing, it should be borne in mind that, as the " hypo " and silver salts leave the film, their weight causes them to sink to the bottom of the vessel, whence they should be rapidly syphoned away.
FUGITIVE SILVER PRINTS.— It is often stated that silver prints made years ago were more permanent than many produced of late, some of which show signs of fading after a few months. As an explanation, the class of negative used has generally been taken into account, as in the early days the negatives employed were much denser, the printing paper (albuminisedl was salted in a strong bath, and the printing carried to a greater depth and more gold deposited in toning. Then, again, the washing was more thorough, and performed more quickly. Long wasliing degrades the brilliancy of the prints. The old method of working was to wash the prints in large dishes alternately in cold and warm water, well draining between each change, the prints by this method being practically freed from " hypo " in about twentj' minutes. Then the prints were made from denser negatives upon paper sensitised with a strong silver bath, and fixed in a stronger fixing bath — in many cases in two fixing baths — and then quickly washed ; and to treatment of this nature has been ascribed the secret of their permanence. It has also been found that prints which are thoroughly fixed, but imperfectly washed, are more permanent than those that have received a thorough wash- ing, but have been imperfectly fixed. There is httle doubt, however, that the mounts employed have, in many cases, been the cause of fading : among prints in the possession of the writer, made upon albuminised paper, some mounted and others unmounted, it is usually the mounted ones that have faded the most, ^^^len gelatino-chloride paper was first introduced we were told that, in a very short time, it would entirely- displace albuminised paper, and that the prints made upon it would be permanent ; the latter claim, however, has not been realised in practice. Prints made upon gelatino-chloride papers when carefully worked do appear to be more permanent than those made upon the older albuminised papers, but it would be incorrect to call them permanent. The degree of permanence appears to depend to a considerable extent upon the method of toning
56
KNOWLEDGE.
February, 1915.
adopted. In our own practice we long ago discarded the combined bath, and always resort to separate toning and fixing, making up the toning bath the moment before it is wanted, being careful not to be too sparing of gold, as it is in the use of this in sufficient quantity that the secret of obtaining good tones lies. If, after toning, the prints are fixed in two separate fixing baths, consisting of three ounces of " hypo " dissolved in twenty ounces of water, and afterwards rapidly washed, good prints should be obtained, possessing a reasonable amount of permanence.
RESTORING FADED SILVER PRINTS.— According to an account by Professor Namias, recently published in the Photographische Korrespondeiiz, faded silver prints may be restored by means of the following treatment. The prints are first bleached in a solution of —
Copper Sulphate ... ... 5 grains
Common Salt ... ... 25 ,,
Water ... ... ... 1 ounce
The bleached image, consisting of silver chloride, is then well washed, and may be darkened by redevelopment with any of the ordinary developers. The greatest vigour is, however, according to Professor Namias, obtained by the use of sodium stannate. For this purpose a one-per-cent. solution of stannous chloride is taken, and a ten-per-cent. solution of caustic soda added until the precipitate first formed is just redissolved. The print is then placed in this until darkened, after which it is well washed.
PHYSICS.
By J. H. Vincent, M.A., D.Sc, A.R.C.Sc.
FABRY AND PEROT'S INTERFEROMETER.— This instrument is of exceedingly simple construction, and consists essentially of a pair of flat pieces of glass. The glass plates are placed with two surfaces separated from each other by a layer of air, the opposed surfaces being partially silvered. The silvering can be best carried out by cathodic deposition. The surfaces of the plates, which are to be silvered and placed facing each other, must be absolutely true planes, and, when mounted, adjustments must allow- them to be brought accurately parallel to each other. In the interferometer the distance of the glass plates from each other is capable of adjustment, while in another form of the apparatus this distance is fixed. When truly mono- chromatic light passes through the plates, the layers of silver, and the air gap, it does so in a number of ways. One portion goes straight through, another is reflected from the second layer of silver, then from the first layer, and then goes on to join the first portion. The second part of the light has thus been reflected twice ; the first has suffered no reflection. A third portion comes through the plates after four reflections, a fourth after six reflections, and so on. The different portions into which the light is divided will conspire together if the increase in length of path for the successive parts is an exact whole number of wave- lengths, so that, if the plates be viewed with a telescope focused on infinity, a system of circular interference bands will be seen. The bands are due to the obliquity of the paths of all the rays except those striking the plates normally. If now the light is nearly, but not quite, mono- chromatic ; if, for instance, it consists of Ught of two different but closely approximating wave-lengths, two systems of fringes will be formed, one for each kind of light. " Thus the apparatus is a true spectrometer, and can be used to separate the components of spectral lines.
APPLICATIONS OF FABRY AND PEROT'S INTER- FEROMETER,— The instrument has been used by Fabry and P6rot in the investigation of the intimate structure of spectrum lines. Thus they showed that the green line of thallium w^as triple, the main line having two weak com- panions towards the red end of the spectrum, and measured the differences between the wave-lengths accurately :
the red cadmium line was proved to be simple. Another application was for the exact comparison of widely differing wave-lengths ; in these experiments the half-silvered plates were separated by as much as 3-2 centimetres.
THE ETALON INTERFEROMETER —In 1902 Fabry and Perot began to use a modified form of their inter- ference apparatus, which they term an " etalon," or standard. This is derived from the more elaborate form by removing the facilities for altering the distance between the plates, which are held at a fixed distance apart by three pieces of invar. This material is practically inex- pansible by heat, so that, when once the distance separating the plates has been measured, it is capable of being treated as sensibly constant. The fine adjustment for parallelism of the silvered plates is made by springs, which can be pressed down by screws on to the plates over the distance pieces, which, by their compression, enable their effective thickness to be varied. One method of calibrating the 6talon is by comparison with the air film of an interfero- meter whose plates can be gradually separated. The measurement of the thickness having been carried out, the 6talon can be used to determine an unknown wave- length. By its means many lines in the spectra of the metals and in the solar spectrum have been accurately measured, these results being now regarded as more reliable than those found by other methods.
DIATHERMY. — An interesting series of articles on the use of high-frequency electric currents for the production of heat in the body of a patient appears in recent numbers of the Archives of the Rontgen Ray. The author (Dr. Cumber- batch) is in charge of the electrical department at St. Bar- tholomew's Hospital, and thus the information may be regarded as authoritative. The electric current provides a unique method of supplying heat to the deep tissues of the body ; other methods of heating the body act on the skin. When high-frequency current is employed no pain is felt, no muscular contraction is produced, and no sensation other than warmth is perceived, even when the current reaches the root mean square value of from two to three amperes. D'Arsonval showed in 1891 that a current of three amperes could be passed through the human body with impunity, provided that the frequency' of alternation was great. Currents of such strength had not been used previously in electro-therapeutics ; and, as they became better known, it was soon evident that the curative effects wliich followed their use were due to heat ; hence the term " diathermy," to distinguish the method from the older ways of applj'ing high-frequency currents in medicine. The apparatus for the production of the currents used in diathermy consists of two transformers, the first to raise the alternating current from the mains to a few thousand volts. The secondai-y current from this first transformer charges a condenser, wliich is discharged through a spark gap and through the primary coil of the second transformer. The oscillations of the current in this condenser circuit have a frequency of the order of a million a second, and produce in the secondary of the second transformer the current (of the same frequency), which is passed through the patient. The design of the apparatus is such that the current which heats the tissues is, as measured on a hot-wire ammeter, adjustable from zero up to two or three amperes. The spark gap is of a very special construction. It has, in one form of the apparatus, a double gap, each a quarter of a millimetre in length, the spark occurring between the opposed faces of polished silver plates. The sparks take the form of blue films that occupy the air space between the discs. The intervals between the successive trains of high- frequency oscillations are very small, so that the blue film appears to be continuous to the eye ; the discharge is accompanied by a hissing sound. The diathermy current is led to the electrodes, which are in contact with the patient by short, well-insulated, flexible leads, the contacts mide with the body by the electrodes being moistened with
February, 1915.
KNOWLEDGE.
57
salt solution. The frequency of the oscillations is not exceedingly high ; and, since the resistance of the tissues is great, the current is not confined to the outer parts of the conducting tissues, as would occur \\-ith better con- ductors and higher frequency. The electrodes and currents can be arranged so as to cause a rise of temperature of a few- degrees only, or the electrical heating may be concentrated on a portion of tissue which it is desired to coagulate and destroy, ^\^len the former method of application is employed the whole body is heated, and the skin becomes bathed in sweat, owing to the convection of the heat by the blood. Some interesting experiments are described, in one of which albumen is coagulated in tlie space between the electrodes connected to the diathermy apparatus, and in another a cube of raw meat is charred. Two disc electrodes, one inch in diameter, are placed on opposite sides of the cube. A central bridge of meat^is soon cooked, and is finally charred.
RADIO-ACTIVITY.
By Alexander Fleck, B.Sc.
MEDICAL USES FOR RADIUM.— Early in the histon.' of radio-acti\'it>' it was disco\ered that the rays produced by atomic disintegration had some effect on the tissue of organisms, and in recent years many in the medical pro- fession have turned their attention to directing such effects to alleviate and cure various diseases. In some forms of disease, such as rodent ulcers, a cure ma^' be confidently expected, provided that sufficient quantities of radium are used. In other and more serious diseases, as, for example, cancer, it is not yet possible to say that a complete cure can be looked for. It seems, however, that the malignancy of the disease is mitigated by the application of radium, and often a cure lasting for a number of years has been obtained. -■Vlthough the disease may recur, it does not necessarily follow that it will do so. The position taken up by the London Radium Institute and most medical men is that, whenever the cancer is at all operable, an excision is made, and the radium treatment reserved for inoperable cases. Considerable hope is entertained that, by judicious com- bination of radium treatment and e.xcision, cancer will soon cease to be the terrible scourge that it is at present.
London, of course, has had for some years now a large quantity of radium available for medical purposes, and several other cities in the United Kingdom have recently purchased quantities to be set aside for use in the treatment of disease.
RADIO-ACTIVITY AT THE BRITISH ASSOCIATION. — In the issue of Nature for November 26th a report is given of the proceedings of Section A (Physical) of the meeting in Australia, and it seems that pure radio-activitj^ occupied a minor position, while the allied subject of radi- ations in general was discussed in a number of important aspects. From the point of view of the radio-active chemist, the most interesting was a joint discussion with the Chemistry Section on the structure of atoms and molecules. Professor H. E. Armstrong seems to have been the chief representative of chemistry, and contributions were made by Sir E. Rutherford, Professor Nicholson, l\Ir. IMoseley, and others. Professor Hicks dealt with the subject from the spectroscopic point of view, and stated that neither by the Thomson nor the Rutherford atom is it easy to explain the spectra of the elements. The real atom seems to be something more complicated than either of these models. The meeting is said to have been more of a s>Tnposium than a discussion ; and, while no new facts or principles of importance have been enunciated, the full report which it is promised will be published in the annual British Association volume will be awaited with interest.
FORMATION OF ACTIVE DEPOSITS.— Very shortly after the discovery of radium emanation it was found that if two metal plates, one positively and the other negatively charged, were placed for a few hours in a space available
to this gas, the negatively charged plate became intensely active, whilst the positive plate had only a very small acti\-it5-. The material that produces the activities so obtained is called the " active deposit."
It is easily proved that the emanation itself is not affected by the electric field, and that therefore it is electrically neutral. The emanation in its disintegration gives oft an a-particle, carrj-ing two positive unit charges, and there- fore we should expect that the remaining part of the ema- nation atom (i.e., after taking away positive electricity from a neutral body) would be negatively charged. If this were a complete explanation of the disintegration of the ema- nation, then the active deposit material would be attracted to the positive plate in place of being, as it actually is, collected on the negative plate. This anomaty is explained by the Uberation of a number of low-speed negatively charged 5-rays by the a-particle in its passage through the atom. There remains, however, the question as to how the small quantity of active deposit is obtained on the positive plate, and tliis problem has been attacked in a number of papers which have recently appeared in the Philosophical Magazine (papers by WelUsch, Walmsley, and Lucian). The main conclusion in aU cases is the same, namely, that when the A member of the active deposit (i.e., the first disintegration product after the emanation) is formed, it always carries a positive charge, but that, just as in the case of an ordinar^^ gas ion, in the course of diffusion it may recombine with another negative ion to become electrically neutral. \Mien this happens this neutral particle will be deposited on the first surface that it meets. The small quantity of active deposit material referred to is therefore obtained from those particles rendered neutral by re- combination which have chanced to come into contact with the positively charged surface.
SEPARATION AND PURIFICATION OF RADIUM. — In a uranium-bearing mineral the greatest possible amount of radium (except in very rare circumstances) that may be present is 3-23 parts of radium for every ten million parts of uranium, and the task of separating this very small amount of material is one that demands a considerable amount of chemical skill. As it is first separated, the radium is contained in a mixture of barium, lead, and other sub- stances, of which the sulphate is comparatively insoluble. The concentration at this stage is usually about 0-2 to 0-5 of a milligramme of radium per kilograrmne of material. This sulphate has then to be converted into some soluble salt, usually the chloride, sulphuretted hydrogen, and then ammonia added to the solution so obtained in order to remove elements of the lead and iron groups respectively. Finally, the radium is obtained in the filtiate from these elements along with the barium. At this stage the pro- cedure is transferred from the works to a chemical laboratory, and the long process of fractionation is commenced. This consists in making a hot concentrated solution of the barium-radium chlorides, which is allowed to cool. It is found that the crj'stals that separate out are richer in radium than the material that remains in solution (usually in the ratio of 5 to 1). This process is repeated a great many times until finally pure radium is obtained. The physical chemistry of the process is verj' interesting, because it IS usually taught that by crj'stalUsing a substance from solution a small quantity of impurity will remain in the liquid, and that the crj'stals will be pure. In the above case the exceptionally small quantities of radium present are concentrated in the crystals. It is found by experience that lead also accumulates in the crystals, and it has to be separated frequently by sulphuretted hydrogen or some other means.
In some Austialian works this process is considerably modified, and an account was given during the course of last year by Radcliff to the Sydney Section of the Society of Chemical Industry', in which pure barium-radium chloride was obtained by saturating the solution obtained from the crude sulphates with hydrochloric-acid gas.
58
KNOWLEDGE.
Februarv, 1915
ZOOLOGY.
By Professor J. Arthur Thomson, M.A., LL.D.
CATERPILLARS' SETAE.— It appears that the de- scription of " aerostatic hairs " on the caterpillars of the Gipsy Moth and Nun Moth was mistaken. The globular swellings at the bases of the hairs were supposed to be air reservoirs, facilitating dispersal by the wind. Riley showed some time ago that the swelling does not contain air, but fluid, and that there is a large glandular cell opening into it. It is probable that the fluid is poisonous, and protective against insectivorous birds.
FORMER CONNECTIONS OF ANTARCTIC CON- TINENT.—In giving an account of the fishes collected by the British Antarctic (" Terra Nova ") Expedition, 1910, Mr. C. Tate Regan, of the British Museum, has taken occasion to examine the evidence in support of the \'ie\v held by many authorities that in the Early Tertiary the Antarctic Continent was connected with Australia and with South America. He comes very definitely to the conclusion that neither the freshwater fishes nor the marine fishes, whether Antarctic or South Temperate, support the theory that Antarctica has connected Australia with South America in Tertiary times. The evidence from other groups of animals seems to Mr. Regan to confirm the con- clusion which he reached from his study of the fishes.
SHORE MITES.— Professor L. A. L. King's recent observations on some littoral mites on the shore near Millport Biological Station show how much interesting material is available to keen eyes. Thus, as to the feeding of Gamasiis [Eugamasus) immanis, it is noted that the mite plunges its chelate chelicerae into the body of living Oligochaetes, tears out a piece, and sucks it dry. As Michael showed, the male inserts his mandibles into the genital opening of the female, and empties the contents of a spermatic capsule into the vagina. Of Gamasiis (Halolaelaps) glabyiusculus it is noted that it survived complete immersion in water for forty-eight hours. The large red Bdellid (Mo/giis Uttoralis) was seen feeding on a small living Dipteron. The smaller, more vivid, more gregarious Bdella longicornis probably feeds on the Collembolan Antirida maritima, common on the shore. This species of Bdella, as Mr. T. J. Evans, of Sheffield, has also noticed, spins a silken tent in autumn.
NUMBERING HAIRS.— Evidence of the definiteness of indi\'idualit5' is always interesting. We know of some simple animals which have always, or almost alwa^'s, the same number of cells in particular parts of their body, and in their body as a whole, and Mr. Phineas W. Wliiting has shown the same sort of specificity in the bristles on the back of the Green-bottle Fly (Lucilia sericata). He studied a group of twelve dorsal bristles, and found that the number is hereditary and the distribution hkewise. There may be a few less or more, but only a few. Reduction rarely goes beyond the loss of two bristles in a single fly. Out of five thousand three hundred and sixty-seven flies bred, there was a reduction of 748'5 in the males and of 455-5 bristles in the almost equal number of females. There were two hundred and ten bristles added in the males, and three hundred and forty-three added in the females.
FREQUENCY OF PARASITES IN FISHES.— The clean and wholesome nature of the flesh of fishes is well known. Its relative freedom from parasites is noteworthy and of practical importance. But the number of parasitic worms found in the intestines, and in other parts of the food- canal, is enormous. Dr. W. Nicoll, one of the foremost helmintliologists, has examined eight hundred and forty-five fishes (one hundred and two different kinds) from around our coasts, and has found eighty-one per cent, with parasites (of over fifty different kinds). Of four hundred and seventy- five fishes from Plymouth, three hundred and eighty (eighty per cent.) were infected : fifty-six per cent, with flukes, forty-four per cent, with tapeworms, forty-eight per cent.
with tlireadworms, and two per cent, wth Echinorhynchs. Millport fishes yielded the same percentage, St. Andrews fishes eighty-three per cent., and Aberdeen fishes ninety-one per cent. This large incidence of parasites is remarkable : it throws some li,ght on the stern character of the struggle for existence. In most cases, probably, the parasites do little harm unless they reach a host unaccustomed to them.
THE MAN-OF-WAR INFUSORIAN— A glimpse into the intricacy of things is afforded by E. Penard's description of a ciliated Infusorian, which he found in a marsh near Genev;i, and names Legendrea bellerophoyt. The genus was established by Faur^-Fremiet, but the species, bellerophon, which we have translated " man-of-war," is new. It is from 120-180^ in length, and about a third as broad : it has a slit-like mouth, a horse-shoe-shaped nucleus, a large contractile vesicle, and many other features with which we are familiar in ciliated Tnfusorians. But the remarkable feature is that on each side of the somewhat man-of-war- shaped creature there project about ten papillae at regular intervals, like the guns from a frigate. Each of these papillae bears at its blunt extremity a group of stinging threads, or trichocysts, from which, again, very delicate, probably poisonous filaments can be protruded. Each papilla is like a mitrailleuse, and a very effective weapon. There are trichocysts on other parts of the Infusorian, but they explode only on the projecting papillae. In a very striking way they move or are moved to the bases of the papillae, and accumulate there, " waiting their turn " to pass up, or to be passed up, to the tips of the papillae. When the delicate filament is protruded from the exploded trichocyst a minute viscous drop of poison appears at its ruptured end. The well-armed Infusorian swims slowly, and is carnivorous. It is wont to attack a minute Rotifer called Diplax lyigona.
ANIMAL HYPNOSIS.— When a Snake becomes a stick, or a Hen lies immobile on the floor with a chalk line in front of its eyes, or a Crayfish stands on its head, or a Ground- beetle (such as Scarites buparius) feigns death on being shaken, we have to deal with animal hypnosis. In a recent investigation Professor Mangold defends the position that animal hypnosis is analogous with human hypnosis, and on the physiological side the resemblance is certainly close. Mangold's definition of animal hypnosis is as follows : A reflex tonic inhibition of locomotion and position-adjust- ment, induced by a sum of afferent stimuli, resulting in a sleep-like state in which there may be great changes in muscular tonus (first increase, and then decrease) and decrease of sensitiveness to many kinds of stimulus, e.g., of a painful sort. One of the many difficulties concerning animal hypnosis is its relative uselessness. It may perhaps be of service when a ground-bird, hotly pursued, squats motionless, or when a mammal " plays 'possum " ; but even this has not been proved to be " hypnosis " in the strict sense, and in most cases among backboned animals the capacity is known only in the laboratory. Among Arthro- pods it is of great service in stick-insects, wliich pass into hypnosis under the stimulus of light, and simulate in their pose the twigs which thev resemble in colour and shape. But in many cases the hypnotic state is readily assumed under various stimuli without any resulting utility being ob\ious. Very interesting is 1he case of the female Galeodes — a fierce and unapproachable creature — wiiich passes into hypnosis when suddenly seized by the smaller and weaker male. It looks as if we had to do with a widespread capacity which persists as a concomitant of an effective nervous constitution, but is only now and again itself brought within the sphere of utility.
ADAPTATIONS OF THE PLANKTON.— Professor J. Graham Kerr discussed in a recent lecture the adaptations of the drifting animals of the sea. Macro- plankton animals, illustrated by jelly-fishes, pelagic anneUds, like Tomopteris, and Salps, often show transparency, or some coloration, which is a garment of invisibility. In the
February, 1915.
KNOWLEDGE.
59
Leptocephalus stage of the Eel the haemoglobin of the blood is actually suppressed. (It is noted, in passing, that red prawns from the deep dark waters are not " red " in their ordinary- habitat, but simply dark. No red rays of light penetrate through the upper fiftj' fathoms, and an object cannot look red unless red raj'S of light are falling upon it.) Jlany of the macroplankton animals are phosphorescent, and the pattern of the Ughts may sometimes help in recog- nition. Sense-organs, e.g., balancing organs, are well developed. Flotation is assisted in many ways, e.g., by the gas in the internal shell of Sepia, or by the s^\^m-bladder of fishes. Part of the lining of the swm-bladder can secrete oxygen, and another part can absorb the gas ; thus increasing or decreasing, as occasion demands, the internal pressure. Thus the fish is able to float at one level without effort.
In the microplankton, such as Radiolarians and Copepods, the problem of flotation may be solved by lessening the specific gravity' of the animal, e.g., by accumulating gela- tinous material in jelly-fishes. Or there may be arrange- ments for gi\"ing increased effect to the \■^scosit^' of the sea- water. This may be brought about merely by diminution in the size of the creature, the ratio of surface to volume increasing with diminution of bulk, or by the development of spinj- or feathery outgrowths. The \'iscosity is lessened with rise of temperature, and thus the arrangements just alluded to are especially well marked in the plankton of the warmer seas.
SEX RECOGXITIOX IX WOOD FROG.— Arthur M. Banta {Biological Bulletin, Volume XXVI) has tried to discover the method of sex recognition in Rana svlvatica, the wood frog. The males distinguish the females (from other males) at a short distance. There may be something in the diSerences of the sexes in swimming and in beha\-iour when approached, and possibly something in the diSerences in colour. But dead females are distinguished from dead males, and it is suggested that a chemical sense in involved. This should be made a subject of experiment. The males test ever^^ frog or mo\-ing object within a radius of severed feet, and their cold-blooded ardour leads to a good deal of fatal " disharmony."
SHORE FAUNAS. — Professor A. S. Pearse distinguishes, at Nahant, ]Massachusetts, the rock beach, the sand beach, and the mud flats. The mud flats are marked by the lack of suitable objects for attachment (therefore no sponges, hydroids, and so on), and bj- the comparative impurity of the water (therefore adaptations for respiration, as in Mya, with its long siphon). The fauna of the sand beach is com- posed largely of burrowing animals and those which are continually being swept in. The rock beach is divided into : (1) the rocks above high-tide mark ; (2) the Bala mis zone ; (3) the Ascophyllum zone, with Serlularia pumila, anemones, Purpura, 'Littorina, and so on ; (4) the Fucus zone, with M\ttlus, Balanus, Acmaea, Purpura, Littorina, Asterias, and so on ; and (5) the Chondrus zone, most thicklj' peopled, with Idothea, Acmaea, Asterias, Cancer, Meiridium, and various Bryozoa.
" Probabl}- no other animal habitat is subject to such a wide range of fluctuations in environmental conditions as the rock beaches along the ocean. The flora and fauna must endure the frigid span of winter and the blistering sun of summer. There is no escape : the tide keeps up its eternal rh}-thm, and the organisms are left exposed to the elements everv time the water recedes. The exposure of the hard substratum to sun, wind, and wave has developed a fauna which consists largely of animals that are : (1) attached permanently or have well-developed clinging organs ; (2) active and hard-shelled or (3) small and ubiquitous ; and (4) mostly very hardy, and able to stand considerable exposure." The animals that have these cha- racteristics most developed have the widest distribution.
" The surface of the rock is a veritable sieve through which the microscopic organic content of the water dis- appears. The barnacles sweep it constantly with their fishing nets : the carpets of clams siphon food into their depths from the turbid water ; Littorinas search ever\- square inch, and sweep it clean ; wherever there is sufficient moisture the Coelenterates and Brj'ozoans spread their deUcate tentacles to seize their share." There is keen com- petition for food and foothold ; it is a crowded battle- ground ; it has been a great school. It is interesting to compare Pearse 's survey at Nahant with that made by Russell and Iving at Millport, on the Clyde.
REVIEWS.
BOTANY.
Practical Field Botany. — By A. R. Horwood, F.L.S. 193 pages. 22 plates. 26 figures. 8-in. x 5-in.
(Charles Griffin & Co. Price 5 /- net.)
Mr. Horwood is doing a great deal to popularise the study of botany and to direct those who take it up into the right way. At the same time, his energies are being devoted to preserving, so far as is possible, our native flora from undue diminution or extermination. The present book will cater for those who are led to study plants through the now far-reaching nature-study movement. It deals with the scope, object, and aims of botany ; it describes the various methods o' raountincr plants ; it touche.s on wild flower tables, on museums which are stationary and peri- patetic. It shows what is being done to encourage the study of botany ; and, after dealing with the Ufe-history of a plant, occupies itself with ecologj-, or the association of plants together into what the author calls " formations ' according to soil and situation. This is the kind of botany which appeals most strongly to the general lover of nature, and broadens the outlook of the systematic botanist. No one who reads Mr. Horwood's book can fail to find some suggestion of use and of interest. We heartily wish the work the success which it deserves, and commend it specially to the notice of nature-study teachers.
\V. M. W.
CHEMISTRY.
Essays and Addresses. — By the late J.\mes Campbell
Brown, D.Sc. 208 pages. 23 illustrations. SJ-in. by
5f-in.
(J. & A. Churchill. Price 5/- net.)
The work of Dr. Campbell Brown included both the aca- demic and the professional side of chemistrj' ; for, in addition to holding the chair of chemistry- in the Liverpool Univer- sity, he was also a public analyst and a consulting chemist. The practical aspect of his work is reflected in the whole of these essa^-s and addresses, which are for the most part of a utihtarian character. They include addresses to the Society of Chemical Industry- on such subjects as " Technical Chemistry- " and the " Ethics of Chemical Manufacture " ; biographical sketches of great chemists ; and historical papers, such as " Chemistry in Liverpool in 1801."
All of these papers are ver\- readable, even by those with- out any knowiedge of chemistry, especially the last two on " .\nalytical Chemistry' as a Profession " and " Science Applied to the Detection of Crime," which are characterised by their sound common sense and keen humour.
Some of the opinions, however, are open to criticism. For example, it seems to us that there is some justification for the pubUc attitude towards mistakes made by an analj-st, against which Dr. Brown protests in several places ; as, for instance, on page 202 : " The public can- not forgive a mistake in an analyst. A doctor makes a mistake, and buries it. A lavvyer makes a mistake, and is
60
KNOWLEDGE.
February, 1915.
paid for it as highly as if he had not. A clergyman makes a mistake, and it is discovered only in the ne.xt world. But if an analyst makes a mistake, he is condemned. He has committed the unpardonable sin."
The difference between the analyst and the other pro- fessional inen cited is that he makes assertions as to matters of fact, whereas the physician, lawyer, and clergymen may express opinions. If the analyst can be shown to be wrong, this mistake is regarded by the public as of the same kind as that of the dentist who pulls out the wrong tooth, or the surgeon who makes a cut in the wrong place. In both of these instances a court would award damages to the victim.
C. A. M.
Tlie Elements of Chemistry. — By H. L. Bassett, B.A., B.Sc. With an introduction by Professor W. J. Pope, M.A., F.R.S. 368 pages. 32 illustrations. 7-in. x 5-in.
(Crosby Lockwood & Son. Price 4/6.)
Professor Pope points out very cogently in his intro- duction that most scientific professions demand some ele- mentary knowledge of chemistry in more than one of its divisions, although a student's work may subsequently have only an indirect connection with the science. It is with the needs of the medical student more especially in view that this book has been written, and it should pro\-e of the greatest ser\dce to those who are preparing for the examinations of the Conjoint Board. It is divided into the four sections : General and Physical Chemistry, Inorganic Chemistry, Organic Chemistry, and Practical Chemistry. Obviously it is impossible within so limited a space to go very tho- roughly into any of these branches, but the book gives a useful summary, and for those who are not working for examinations it could well serve as an inti'oduction to larger treatises. It would be an advantage, from one point of view, if the practical work were distributed throughout the other sections, instead of being put at the end of the book. The theory of chemistry should be supported, not crowned, by experimental work.
C. A. M.
The Chemistry of the Radio-Elements (Part I). — By Frederick SoDDY, F.R.S. 151 pages. 3 figures. 8|-in. x 5|-in.
(Longmans, Green & Co. Price 4 .'- net.)
Part II of this book was issued in 1914, as a result of important advances then made ; to supply the demand consequent on the interest created in the subject by those advances, it has been necessary to publish a new edition of Part I. The new edition has not only been brought up to date, but has been enlarged, and almost completelv rewritten. The fact that this new edition of Part I has been called for is testimony that the scientific public has realised to a great measure the advances that were outlined in Part II.
The book may be roughly divide:! into two halves, the first of which deals with the general principles invol\-ed. In the latter half the chemistry of the radio-elements is described sj'stematically. With regard to the first half, we feel sure that, to any reader who wishes to become acquainted with the broad facts and principles of radio- activity from the physical as well as the chemical stand- point, no better summary could be recommended, provided that he possesses a knowledge of chemical laws and of the elementary facts of general science. The second half of the book will be of greater use to the person engaged practically in radio-active work, and the author's great experience in this direction has enabled him to make this section of the greatest value for use in the laboratory.
The chapter on the " Adsorption, Electro-, and CoUoido- Chemistry of the Radio-Elements " is exceptionally interest- ing, and contains a number of suggestions for further work.
A. F.
EVOLUTION.
Mutual Aid : A Factor of Evolution. — By P. Kropotkin. Popular Edition. 240 pages. 7i-in. x 5-in.
(William Heinemann. Price 1 /- net.)
The issue of a cheap popular edition of Prince Kropotkin's well-known book, " Mutual Aid," is particularly to the point at the present moment. It has been suggested that the wholesale destruction of life among non-combatants and the pillage of their means of subsistence in the present war is part of the ordinary " struggle for the existence." Prince Kropotkin's book, dealing as it does with mutual aid amongst human beings, supports the protest which has been made against such an abuse of Darwin's terminology.
For those who are unfamiliar with " Mutual Aid " we may add that it describes co-operation among animals, among savages and barbarians, and with the craft guilds of the mediaeval city, in addition to more modern instances.
W. M. W.
FARMING.
Impurities of Agricultural Seed, with a Description of com- monly occurring Weed Seeds and a Guide to their Idoitification. — By S. T. Parkinson, B.Sc, and G. Smith, B.Sc. 105 pages. 152 illustrations. 7|-in. x5-in.
(Headley Brothers. Price 3 /- net.)
In few walks of life is the necessity for organised know- ledge at the present time greater than in farming. The agriculturist has learnt, or is beginning to learn, that in the case of many plant diseases there is no cure, and that he must rely entirely upon prevention. Though weeds can be got rid of, the task is often a difficult one, and here it is possible to avoid one common cause of their intro- duction. This is by taking care not to sow seed which is impure. Before, however, a farmer can tell what weed- seeds occur among those which he is buying, he must have some knowledge of the subject. Messrs. Parkinson and Smith are therefore to be congratulated warmly on having produced a veiy useful book. The introduction is very concisely and simply written, while the large number of reproductions of photographs of weed-seeds, of which we are courteously permitted to reproduce a few in Figures 50 to 58, will be a very great help, not only to the farmer, but to the seed specialist. There are one hundred and fifty- two of them in all, and each is accompanied by a brief description giving the size of the seed in fractions of an inch and in millimetres.
W. M. W.
GEOLOGY.
Engineering Geology. — By H. Ries and T. L. Watson. 672 pages. 104 plates. 225 figures. 9-in. x 6-in.
(J. Wilev & Sons, New York ; Chapman & Hall, London. Price 17/- net.)
Geological conditions affect many engineering operations, especially in railway construction, tunnel driving, reservoir building, and works for the prevention of coast erosion, improvement of rivers, and water supply. Geological con- siderations also affect the selection of building stones, road metals, cement materials, and clays, as well as the materials such as coals and ore deposits, the mining of which has long been recognised to have a geological basis. There has long been a need for a work dealing with geology from this practical point of view in its relation to various phases of industrial activity. The book under review suppUes this need very satisfactorily. The authors throughout emphasise the practical application to engineering of all the topics treated. The book is intended primarily for civil engineers, but it will be found of considerable value to others interested in applied geology.
The first three chapters deal compactly but quite effectively with the mineralogy and petrology necessary to complete comprehension of the subject. They are followed by chapters deahng with structural features and meta-
February. 1915.
KNOWLEDGE.
61
tt #
Figure 50. Charlock, {Brassica siiiapis.f X 10.
Figure 51. Hare's Ear.
(Bupleurum rotitiidifoliiiDi.
X 10.
m
Figure 52. Yellow Rattle, (Rhinanthiis Cristagalli.) X 4.
Figure 53. Wild Radish, Runch, (RapJumiis raphaiiistniiii.) X 4.
Figure 54. 0.\-tongue, {Hclminthia echioides.) X 10.
IK
>
Figure 55. Cat-mint, Cat-nip, iNepeta Cataria.) X 10.
»■,
»
*g^-_-^-
i?,V-:
Figure 56. White Campion, {Lychnis alba.) X 10.
99
Figure 57. Ivj'-leaved Speedwell, {Veronica hederaefolia.) X 4.
^ ''•^
Figure 58. Curled Dock, (Rtiinex crispits.) X 10.
THE SEEDS OF COMMO.NLV OCCURRING WEEDS. (From ■' Impurities of Agricultural Seed," by S. T. Parkinson and G. Smith. By the courtesy of Messrs. Headley Brothers.)
62
KNOWLEDGE.
February. 1915.
From a /.hotografh h Alfred E. Tongc, F.E.S.
Figure 59. Six-belted Clearwing 5 on flower of thrift. iSesiii iclnu'iiiiioiii/onnis.)
Natural size.
By the courtesy of Wild Life.
Febri-arv. 1915.
KNOWLEDGE.
63
inorpMsm of rocks, and with rock weathering and soils. Chapters V to X deal more directly with the practical aspects of geology in relation to surface and underground waters, land sUdes, waves and shore currents, lakes and glacial deposits. The remaining chapters demonstrate the importance of geological principles in the winning and selection of building stones, hmes, cements, plasters, clays, coals, petroleum, road metals, and ore deposits.
The book is illustrated with one hundred and four excel- lently selected and well-executed plates and tvvo hundred and twenty-five figures, some of which are open to criticism. Thus Figure 73, which, according to the designation, is intended to show monoclinal attitude of strata, shows simple dip, and is, moreover, not referred to in the text. In Figure 74 the shading does not correspond in the t^vo drawngs. The plan and section do not correspond in Figure 116, whilst in Figure 64 there is an extraordinary lack of deformation in the strata adjacent to a broad fault-breccia zone.
Since the book has been written for the .\merican student, we can hardly be surprised that American examples abound in the text, and that Anierican literature is mainly cited in the concise lists of literature at the end of each chapter. Never- theless, the plan of the book is so good that European engineers will find its methods and principles adapted to all their problems, although it is to be hoped that this book will stimulate some worker wdth the necessary quaUfications of engineer and geologist to summarise the extensive but scattered British Uterature on the same subjects.
G. W. T. MATHEMATICS.
A First Course in Mathematics for Technical Students. —
By P. J. Hales and A. H. Stuart. 125 pages.
7|-in.x5-in.
(University Tutorial Press. Price 1 /6.)
The material in this little book is practical and much condensed. It will probably be found useful to the type of student for which it is intended. The explanations seem to be full in some cases and meagre in others ; but those who have had experience in practical work with artisan students must know that their difficulties are not the same as those of the ordinary schoolbov.
W. D. E.
Elementary Mathematical Analysis. — B}' C. S. Slighter. 490 pages. 7i-in. x 5 J-in.
(Hill Publishing Company. Price 10/6 net.)
A textbook in which efficiency (in Lord Rosebery's sense) appears to be the watchword. Everj'thing is standardised, even to the size of the paper on which the student works in pen and ink It almost comes as a surprise that a type- writer is not insisted on, and that no American standard of pronunciation of the letters of the Greek alphabet is set up. The author lays stress on the possibilities and responsibilities of character-building in a mathematical course, and we find occasional hints, amounting to commands, intended for the instructor. Although the inspiration of Professor Klein of Gottingen is freely acknowledged, the book should prove innocuous, and even beneficial, to English-speaking teachers of mathematics dispersed throughout the world.
W. D E.
Plane Trigonometry. — Bj' C. I. P.\lmer and C. W. Leigh. 288 pages. 9J-in. x 6J-in.
(Hill PubUshing Company. Price 6 /3 net.)
The treatment of the subject in this book is not at all that which has been adopted in many recent textbooks. The authors begin with the measurement of angles, positive and negative, and make use at once of Cartesian coordinates . There is something to be said for this method of procedure ; for most boys are made famUiar with graphs nowadays before beginning trigonometry, and it is just as well to make use of this famiharity. The trigonometrical ratios
are defined at the outset for the general angle, and then specialised for the acute angle. Many teachers have done this in times past, and with success in the case of intelligent boys. The clear diagrams in this book seem to indicate that the authors have themselves found this plan successful. The second part of the book consists of a xery good set of tables, with full explanations, the angles from 0° to 360° being all included. Altogether the book merits the attention of teachers, and can be recommended without hesitation for intelligent students who wish to obtain quickly a practical knowledge of the subject. By way of criticism, it may' be said that the saving of time involved in writing esc e for cosec e must in practice be very small, and may cause confusion.
\V. D. E.
NATURAL HISTORY.
Ktld Life : An Illustrated Monthly, Vol. VI, No. 1. —
Edited by Douglas English. 32 pages. Numerous
illustrations. 12-in. x 10-in.
(The Wild Life Publishing Co. Price 2 /6 net.)
An editorial in Wild Life for January frankly states that its issue was delayed until it had been ascertained to what degree the war had affected its subscription hst. The fact that once more the magazine has made its appear- ance shows that the thanks offered to the readers is not an empty compliment. The number contains, as usual, some excellent photographs, of which we may mention Mr. Oswald Wilkinson's picture of the male willow warbler cleaning its nest. Mr. Alfred E. Tonge concludes his illustrated account of " British Clearwing Moths." The first part of this appeared in the December number, and from it we are here permitted to reproduce Figure 59, which is an exceedingly good representation of the six- belted clearwing [Sesia ichneutnoniformis). Another picture in the current issue, which is very striking, is INIr. D. Seth Smith's photograph of a Guinea baboon, used to illustrate Mr. E. G. Boulenger's monthly " Notes from the Zoological Gardens."
W^ M. W.
PETROLOGY.
Textbook of Petrology : The Igneous Rocks. — By F. H. Hatch. 429 pages. 164 illustrations. 7i-in. x5-in.
(George AUen & Co. Price 7/6.)
According to the preface, the seventh edition of this well- known textbook on Igneous Rocks has been prepared in order that it may constitute the first volume of a general work on petrology, the second volume being the recently issued " Petrology of the Sedimentary Rocks," by Hatch and Rastall. ^^'hile the general arrangement is the same as in the fifth edition, much of the text has been revised, and new chapters on the pyroclastic and the metamorphosed igneous rocks have been added. The book is divided into four parts, the first being concerned with the physical characters of rocks, the second with the rock-forming minerals, the third with the classification and description of the various rock-types, while in the fourth an account of the distribution of these types in the British Isles is given. The first two parts are eminently satisfactory, and the facts are presented in a most lucid and readable form. The intioductory chapters in the third part are not so satisfactorj', chiefly owing to the fact that the classification adopted is that of siUca-percentages, and that the graphical methods of indicating the relation of rock-groups, which are described, are the " oxide " methods of Iddings and Broggcr. No mention is made of quantitative classification, either on the basis of norm or mode, nor of the exceedingly useful graphical methods based on these factors.
It is somewhat strange to find that most of the ultra-basic rocks are relegated to the hypabyssal division, as many of these are commonly plutonic. This also tends to obscure the close relationship which sometimes exists between diorites and hornblendites. The fourth part should prove of great use, as it is very complete, though in places it appears
64
KNOWLEDGE.
February. 1915.
to be not quite up to date. Thus, no mention is made of the great variety of alkaUc rocks described by Tyrrell from Ayrshire, nor of Shand's elaborate investigation of the Loch Borolan complex. The reproduction of the map of the Loch Garabal area has the same inaccuracies as in the fifth edition. The value of the book is enhanced by a large number of excellent microphotographs, illustrative of rock types. The figure of a teschenite on page 233 apparently contains no analcite. As a whole, the book is admirably- got up, and misprints are rare ; one, however, occurs at the foot of page 185 and another on page 107, where " hydronephehnite " is used instead of ' hydronephelite." In a future edition more references to papers containing the original definitions of rock-names might be given. From the point of view of the readers for whom the book is intended, these defects are of small importance, and do not detract from the merits of an edition which should prove as useful to students and teachers now as previous editions have done in the past.
A. S. YEAR BOOK.
Penrose's Annual. — Edited by William Gamble, F.R.P.S. 148 pages. 92 illustrations. 10-in.x7-in.
(Percy Lund, Humphries & Co. Price 5/- net.)
Penrose's Annual, which is the twentieth volume of the " Process Year Book," is one which should be in the hands of all who are interested in modern printing and illustration . The letterpress is a very fine example of printing, though perhaps to some the hues of the heavy old-faced type are a Uttle too close together to do full justice to it. As usual, the illustrations are exceeding^ good, and their subjects
very varied. There is still a tendency, especially among those used for trade purposes, to have heavy borders of various \vidths and tints, which detract much from the effectiveness of the print, in so far as they take the attention of the eye from it. As the plates are not numbered nor paged, it is difficult to refer to any particular one ; but we think the frame round the portrait of Mademoiselle Gina Palerme, with its eye-dazzling corners, is an example of what should be avoided. The frontispiece is a portrait of SirWiUiam Crookes, P.R.S.,in colour. His academic gown, however, appears flat and unnatural ; and even here we cannot get away from ornamental borders. One of the features of the year mentioned by the Editor is the develop- ment of rotary photogravure. The article by " Macbeth," on " Efficiency in Press Advertising," is well worth reading. Among many articles of practical utility is one on " Har- monic Vibrations " by Mr. Douglas Cowley, following up the suggestion that harmonographs should be used in connection with bank-note engra\-ing by proposing that they should be also used for the borders of cheques or name- plates, or as the headings of various kinds of commercial paper. There are still some who think that simplicity is bad taste. We fancy that more is being done in the way of coloured collotypes than Mr. Yerbury seems to imagine. Mr. J. R. Riddell asks the question, "Is a scientific training necessary ? " and says that, when one is in a reminiscent mood, and compares the conditions and require- ments of the crafts to-day with those in vogue some twenty years ago, the answer must be a most emphatic " Yes." We are glad that the Editor did not (owing to the war) break the continuity of twenty years' consecutive publica- tion, and decided " to carry on."
W. M. W.
NOTICES.
THE BRITISH JOURNAL PHOTOGRAPHIC AL- MANAC, 1915 (fifty-fourth issue), has just been published by Messrs. Henry Greenwood & Co., Ltd. (price 1 /- net, paper ; 2/- net, cloth). In addition to the usual guide to processes and the handy tables of value for reference, two long articles appear, one on enlarging and the other on photo-micrography.
ANTI-VIVISECTION.— A"a/uye has a scatliing article on the action of the anti-vivisectionists, who are in\"eighing against protective treatment for tj'phoid fever. The success of the treatment and the help which it must give to this country in the war are very great. We wonder whether it would not be possible to show that the anti-\'i\isectionists are prejudicing enlistment, and should be dealt with under the Defence of the Realm Act.
THE STAR ALMANAC— Messrs. Simpkin, Marshall and Co. have issued the Star Ahnanac for 1915 by Mrs. H. Periam Hawkins (price 6d. net). This contains much in- fonnation, and should appear on the wall of every astro- nomer's stud}-. Two other publications by the same authoress are invaluable for reference : The ABC Guide to Astronomy (price 1 /6 net), now in its third edition; and the Revolving Star Map (price 1 /- net), an excellent plani- sphere with a movable declination scale.
THE ALCHEMICAL SOCIETY.— At the sixteenth meet- ing of the Society- the first of a number of papers forming a symposium on mediae\-al philosophy was read by Lieutenant- Colonel Jaspar Gibson, V.D., LL.B. (Lond.), on " An Inter- pretation of Alchemical Symbolism with reference to the Works of Edward Kelly." In this there were dealt with certain analogies between the speculations of the mediaeval alchemists, the doctrines of ancient Indian philosophy, and the theories of modern science. At the seventeenth meeting on January 8th the subject of " Alchemical Tradition " was discussed by Mr. Gaston de Mengel.
THE ROYAL COLLEGE OF SURGEONS IN IRELAND. — The President, Vice-President, and Council of the Royal College of Surgeons in Ireland have decided to place in the College a pei-manent record of the names of all the Students, Licentiates, and Fellows of the College who are at present serving with His Majesty's Navy and Expeditionary- Forces ; and, further, to erect a suitable memorial to all such as fall in the war. The President, Vice-President, and Council w-ill be glad if the relatives and friends would communicate the names of such Students, Licentiates, and Fellows to the Registrar of the College.
ENGLISH FILTER PAPERS.— We are glad that Messrs. Balston, Ltd., the makers of the celebrated Whatman drawing paper, are making filter paper to replace that wliich previously came from Germany. The specimens which they have sent to us have been tested, and have been found to be rapid in their action, while they effectively retain fine precipitates. For commercial analysis and school work they are all that could be desired. For the most accurate scientific work, however, the amount of ash is too high, but filter papers washed with acids are in course of preparation to meet the demand for " ash-free " paper. We hope that our readers will take advantage of Messrs. Balston's work.
SHIPLEY & MACBRIDE'S ZOOLOGY has been thoroughly revised, and the third edition will be published shortly by the Cambridge University Press. The science of Zoology has made such ad\'ances in the eleven years which have elapsed since the publication of the second edition of this textbook that it has become necessary to rewrite considerable portions. The newer discoveries in the laws of inheritance are dealt with in the Introduction, the chapter on Protozoa has been radically changed, a chapter on Gephyrea has been added, the chapter on Arthropoda has been largely rewritten, and many changes have been made in the section dealing with Vertebrata. There are many new illustrations.
February, 1915.
KNOWLEDGE.
LONDON COONTY&WESTMINSTER BANK
(ESTABLISHED IN 1836.
LIMITED.
HEAD OFFICE
41, LOTHBURY, E.G.
CAPITAL, i;i4,000,000 IN 700,000 SHARES OF £20 EACH. PAID-UP CAPITAL - i;3,500,000 I RESERVE - - i;4,000,000.
The Kt. Hon. The VISCOUNT GOSCHEiN, Chairman.
WALTER LEAF, Esq., Deputy-Chairman.
Joint General Managers: F. J. BARTMORPK. J. \\. BUCKMURST,
Secretary :
A. A, KEMPE.
BALilLlNCK SHEET, 31st December, 1314.
|
Li.\niLrnKs. |
ASSETS. |
||||||||
|
£ |
.s. |
il. |
C.^SH— |
r |
s. |
d. |
£ s- |
d. |
|
|
Capual— Siibscribeil £14.000,000 |
In hand and at Hank of England Money at Call and .Short Notice |
22,524,904 5,634,632 |
6 11 |
3 1 |
|||||
|
700,000 Shares of £20 each. £5 paid |
:!,500.000 |
0 |
0 |
2S,159,.'i36 17 |
4 |
||||
|
Reserve |
4,000,000 |
0 |
0 |
Bills Discounted |
18,369,283 11 |
7 |
|||
|
Investments Depreciation Accoi'nt |
250,000 |
0 |
0 |
'Investments — |
|||||
|
Current and Deposit Accol:nts |
99,312,563 |
0 |
0 |
Consols (of which /1,400,210 is lodged for Public .Accounts), War Loan, and |
|||||
|
Circular Notes, Letters of Credit, Commission Loans, and |
other Securities of, or guaranteed bv, |
||||||||
|
OTHER Accounts, including pmvisiou for Contingencies ... |
2,019,037 |
16 |
1 |
the British (.ovemment |
10.550730 |
12 |
8 |
||
|
Acceptances eor Custo.mebs |
4,182,337 |
1/ |
9 |
Goveniment Guaranteed RaiKvav |
|||||
|
Endorsements on Bills Negotiated |
93.730 |
0 |
0 |
Stocks and Debentures |
l,lo3,4S.3 |
6 |
4 |
||
|
Rebate on BiLLsnot due |
96,782 |
4 |
9 |
Corporation Stocks, and British |
|||||
|
Profit and Loss Balance, as below |
531,987 |
3 |
3 |
Railway Debenture Stocks Othoi Iii\?stnients |
1,221 463 1,736,440 |
b 7 |
11 8 |
14.647,092 12 |
- |
|
This statement does not include the Bank's liability |
LONIH)N COUNTV .AND WeST.MINSTER BaNK |
||||||||
|
under its euarantee to the Yorkshire Pennv Bauk, |
(l'.\Ris) Limited — |
||||||||
|
Limited, for £223,214. |
4,000 £20 Shares fully paid \ 16,000 £20 Shares £7 iOs. paid /- .Advances to Customers and other .Accoun iiioratoriinn Stock ExcJiance Loans) ... |
200,000 0 46,617,340 18 |
0 |
||||||
|
rs (includin |
? pre- |
||||||||
|
* Investments officially quoted have been valued at or under prices current on 27th Julv, the date of the last |
5 |
||||||||
|
official making up before the closing of the Stock |
Liability of Customers for .\ccfptences, |
as per contra |
4.182,337 17 |
9 |
|||||
|
Exchange. Investments made since that date are valued at cost or under. |
Pills Negotiated, as per contra |
93,730 0 |
0 |
||||||
|
Bank and other Premises fat cost, h-Si amounts wntten o9) |
1,717,106 4 |
2 |
|||||||
|
£113,986,428 |
1 10 |
£113,986,428 1 ID |
|||||||
|
2)r. PROFIT AND |
LOSS |
ACCOUNT. |
Cr. |
||
|
To Interest paid to Customers ,, Salaries and all other expenses, including Income Tax and .Auditors' and Directors' Remuneration ,, Rebate on Bills not due carried to New -Account „ Interim Dividend of lOJ per cent, paid in .August last „ Amount written off Investments, for Depreciation , Further Dividend of 10^ per cent., payable 1st February next {making 21 i per cent, for the year) ... £371,875' 0 0 ,, Balance carried forward '. ... 160.112 3 3 |
£ s. 922,586 12 1,299,809 12 96,782 4 371,875 0 336,600 0 531,987 3 |
d. 1 5 9 0 0 3 |
By |
£ s. Balance brought forward from 31st De- cember, 1913 Gross Profit for the year, after making provision for Bad Debts and Contin- gencies, and including Rebate brought forward from 31st December last |
d. £ s. d. 156,644 11 6 ... 3,402,996 1 0 |
|
£3,559,640 12 |
6 |
£3,559,640 12 6 |
|||
GOSCHEN.
WALIER LEAF, ,
MONTAGU C. TURNER, )
I
AUDITORS' REPORT.
F. J. BARTHORPE, \Joml General T. W. BUCKHURST. / Maiiaaer!. t. J. CARPENTER, Chief .icmmlani.
We have examined the above Balance Sheet and compared it with the liooks at Lothbury and Lombard Street, and the Certified Returns received from the Branches.
We have veritied the Cash in hand at Lothbury and Lombard Street and at the Bauk of' England and the Bills Discounted, and examined the Securities held against -Money at Call and Short Notice, and those representing the Investments of the Bank.
We have obtained all the information and explanations we have required, and in our opinion the Balance Sheet is properly drawn up so as to exhibit a true and correct A'iew of the state of the Company's affairs according to the best of our information and the explanations given to us, and as shown by the Books of the Company.
FRED. JOHN YOUNG, F.C.A., I , ,.,
London, \m January, 1915. G. E. SENDELL, F.C.A., | Auauors.
KNOWLEDGE.
February, 1915.
"B.J. ALMANAC 1915," The big book of photo- graphic tormulae ; all methods, hints, etc.; over 1000 pages. Now ready.
" B.J. ALMANAC " contains a comprehensive treatise on " Photo-Micrography," by Dr. Duncan J. Reid. From your flealer,
"BRITISH JOURNAL PHOTOGRAPHIC ALMANAC.
1915." A libran- -n itsell. From all pliotngraphic dealers. Pi-ppr co\'er 1 /- )icl, cloth-bound 2/- net ; or, post free, from the Publishers, HENRY GREENWOOD & CO., LTD.. 2A, Wellington Street, Strand, W C, Paper cover 1 /6 "t■^ cloth-bound 2/6 >u'l. Abrnntl, 2/- and o'-.
CLARKSON'S
SECOND-HAND
OPTICAL MART.
TELESCOPES.
,' -ifi W'ray, mount- ed on massive oak lath stand with stretchers, hori- zontal and vertical movements by Hooke's joint, slow motions.large finder, 4 astro, and I da\- eyepieces - - £40
ll.Negretti & Zambra aha/-,
tuider. I .lav, -.
4-1
a^tros., in case .. .. 25 o o
3i-iii. Baker, on altaz. stand, horizontal
and vertical motions, finder, day and
2 astros. .. .. .. ..17100
3i-in. Dollond, on aliaz. siani.1, finder, da>-
and 2 astros. . .. ... 12 10 O
3-in. Steward, on altaz. with equatorial
(undivided circles), i day, 2 astros. .. I I 10 O j-in. Wood, I ;istro. and r dav eyt;pit;ces . 4 o O
Manyotherj.. AK" !''.\'-pi*-i ■--., i'lu-i-Ts, Diasonals, etc.
MICROSCOPES.
■ S 15 o
Handle Model.
8 8
6 15
Watson '* Edinburg^h
Student's *' llimn.u-
lar, 3 eyepieces. 2-iii.,
i-in., A-in., polari-
scope, and case Watson " Hdinburgh
H," 2/3, 1/6, 1/12 o.i.,
2 eyepieces, triple
riosepiece, and Abbe Baker "D.P.H." Stand,
triple nosepitfce. Abbe,
and case Beck's Lartje '* London"
spiral, Abbe and iris, triple iiosepiece,
2 eyepieces, 2/3 and 1/6, as new , . Watson "Fram," eyepiece, spiral.
Abbe and iris, double nosepiece, 2/3
and 1/6 Beck Small "London," spiral, Abbe
and iris, double nosepiece, 23 and 1/6 6100 Swift "Discovery," eyepiece, 2/3.
1/6, doubl'.- nosepiece .. ' ., ., 5 1 5 o
Baker Student, eyepiece, A and D
Zeiss objectives, double nosepiece .. 5 10 O Bausch & Lomb Student, i eyepiece
double nosepiece, 2/3 and 1/6. - . . S O O
Many others. AKo Objectives (a large stock by all ihe leadnig makers), Eyepieces, Double and Triple Nose- pieces, Condensers, Lamps, Spectrosropes, Microtomes,
PRISM BINOCULARS
BY ROSS, ZEISS. GOERZ, etc.,
FOR SALE
AND WANTED.
338
HIGH HOLBORN
(Opposiic C,i.:\\ Inn Recall,
LONDON.
MICROSCOPY.
SPECIALLY ATTRACTIVE SLIDES FOR POPULAR EXHIBITION tV: STUDY.
Zoology. Marine and Freshwater.—
Unique preparations, i.vithoi(t pyfssityc, in their natural form and beauty for Dark Ground (or transparent). Zoophytes^ Medus(P, Polyzoa, with their glorious array of tentacles; Holothurians with wheel plates, etc. ; a series of the curious Salptp and other Tunicates ; young (j-<'(^/£\v developing in their eggs ; the celebrated Lance- let ; also the Radiolarian Spluprozouin, the " Volvox of the sea," etc., etc.
Insects and Parts. — V.a.r\B.oi Plumed Gnat (also for polariscope). Superb tongues of the rare Sylzian IVasp and Hornet, also piercing organs of the Cacl^y, etc., etc.
Specia
Cements. Forceps, Scissors, etc., Mounlin-ii and Dissecting-
for
SECOND-HAND
INSTRUMENTS,
OBJECTIVES, &c.
NEW LIST
NOW READY.
Post free on request.
To Beginners.— K.xpert advice freely given on selection ■.>f snUaMe equipment; much time and neeilless expense ^:an thereby be saved. Write or call.
UfAMTCn Microscopes, Objectives, etc., or whole ttwn ii-MJt Outfits purchased for Cash.
KXCHANGES MADE.
CLARKE & PAGE,
23, Thavies Inn, Holborn Circus, LONDON.
LIVING SPECIMENS
FOR THE
MICROSCOPE.
Volvox globator, Desnilds, Diatoms, Spirogyra, Aniceba, Actinophrys. Spongilla, Vorticella, Stentor, Hydra, Cordylopohra, Stephanoceros. jMelicerta. Polyzoa. and other forms of Pond Life, Is. per tube, with printed drawing, post free. Thomas Bolton, Naturalist, 25, Halsall Heath Road, Birmingham.
MINERALS
FOR ALL PURPOSES
I N ( r r 1 ) I N . .
Experiment, Wireless, Incandescent Mamies, Radio-Active, Steel Making, &c., &c.
JAMES R. GREGORY & Co.,
Mineralogists, &c.,
139, Fulham Road, South Kensington, S.W.
Telephone : Westerii •J,S41. Telegrams: "Meteorites, Loiulon."
SECOND-HAND DEPARTMENT.
Microscopes, Telescopes, Spectroscopes, Binoculars, Surveying Instruments, &c.,
BY THE BEST MAKERS AT MODERATE PRICES.
Lists sent post *ree on request.
Scienh'/Ic lnst>ui'!i->its Bou^'il. E.i\h.i>i^^t\i and Sold on L onuHisshin.
JOHN BROWNING,
146 STRAND, and 72 New Oxford St.,
LONDON.
1 elegranis ; 'AUK.S," LONDON.
leltiphone 8:i4 GKRRARD.
Established i760
Stevens' Auction Rooms,
38, KING ST,, COVENT GARDEN, LONDON, W.C.
Every Friday at 12.30, Sales are held at the Rooms of MiCKOScopES and Slides, Tblescopes, Surveying Instkuments, Electrical and Scien- tific Apparatus, Cameras and Lenses, Lanterns AND Slides, Cinematographs and Films, in great variety. Lathes and Tools, Etc.
(Joods may be sent for inclusion in early Sales.
Settlements made one week after disposal.
Catalogues and all Particulars Post Free.
Valuations fur Probate or Transfer, and Sales cnn.
dueled in any part of the Ciiuntr>.
Minerals, Rocks, Fossils, Metallic Ores, Rough Precious Stones, &c.
A Large Assortment from all parts of the world always on view, and at all prices. Inspection invited.
Crude Mineral for Chemistry Students
aad TechiiJcai Sctools.
Single Cystals and Teaching Specimens m Great Variety.
RICHARDS' SHOW ROOMS.
48 Sydoey Street Ftilbam Road, South Keasington, London, S.W.
rRicii Lii r^ I Ri I
F. WIGGINS & SONS,
102, t03, 104, Mmories, LONDON. E
Contractors to H.M Government
FOR
LAMPS,
STOVES.
VENTILATORS,
ELECTRICAL WORK
AND ALL PURPOSES.
Largest Stock in the World. Tel. No. 2248 Avenue.
Printer of " Knowledge,"
JOHN KING,
Uxbridge, Southall, and Ealing,
T s favourably equipped for the PRINTING of *■ Scientific Books, Brochures, Catalogues, .S;c., and will be pleased to submit estimates.
Address all Communications to
213, UXBRIDGE ROAD, EALING, LONDON, W.
■Plioce: 1144 EaliOfi-
Binding Cases for Knowledge Volume, 1914.
IN BLUE CLOTH, WITH GILT DESIGN AND LETTERING.
!s. '.lit. net each; by Post, 2s.
KNOWLEDGE OFEICE, ,\veiuie Chainbers. Bloomsbiirv Square, Lnmlcn, W.C.
A most acce/ttable Gift at any time
KNOWLEDGE VOLUME FOR 1914
Containin^i 440 Pa^es "itli 425 Illustrations, many being Full Page Plates.
Boiiini ill Rliip Cj-itii, (hIi [i..--,i-ti .ni.l 1 ,r:i fri in u , 15,- lit.-!, prist free within the United Kin-iloni.
Publishing Office: AVENUE CHAMBERS, BLOOMSBURY SQUARE, LONDON, W.C, or through any Bookseller.
February, 1915.
KNOWLEDGE.
vu.
WATSON'S BRITISH-MADE MICROSCOPES
Special arrangements have been made for prompt supplies of
Watson's Microscopes and Accessories
to replace those of Continental mabe that are unobtainable in consequence of the War.
NO INCREASE IN PRICES
The 24^.'' Edition of Watson's Gataiogue of Microscopes and Accessories,
192 pages, has just been issued, and contains new models, new accessories, and many improvements.
Make Your Monocular into a Binocular
Microscope. It can now be done by the use of a WATSON'S New
"BICOR"
BINOCULAR
ATTACHMENT
(Patent applied for)
It offers many advan- tages, among which are the following : —
It is attached to a Monocular Microscope in the same way as a Revolving Nose-piece.
Tube length can be varied and interocular width adjusted to any extent.
Brilliance of image in both tubes the same.
No sacrifice of defi- nition is observable.
The above, with many other important improve- ments and introductions, including a series of
APOCHROMATIC OBJECTIVES,
are to be found in Wat- son's newly -published Catalogueof Microscopes. \Posi free on application.
"Bicor" Binocular Attachment. "A'" Screw to attach to Monocular Body, "B" Screw to receive Objectives. *C" Screw to adjust for width of eyes.
W. WATSON & SONS, LTD.,
Contractors to Ib./IE). Covernments, 313 HIGH HOLBORN, LONDON, W.C.
Branches : 16 Forrest Road, Edinburgh ; 196 Great Portland Street, London, W.
DEr6T5 :
2 Easy Row, Birniinflham; 78 Swanston Street, .Melbourne, Australia;
212 Notre Dame Street West, .Montreal, Canada.
ptical Works— HIGH BARNET, HERTS. ESTABLISHED 1837.
The BECK BINOCULAR
BECK BINOCULAR MICROSCOPE.
No. 1031 P.S.
(Patent applied for)
Not only an advance on previous Binoculars, but better than a iMonocuiar with all powers.
1. Resolution equal to that
of a Monocular.
2. Equal illumination in
both eyes.
3. Short tube length, mak-
ing Microscope com- pact.
4. No special object-
glasses or eyepieces required.
5. Standard angle of con-
vergence.
6. Stereoscopic vision.
7. Binocular vision, saving
eyestrain and giving better results than Monocular vision.
8. Converted into a Mon-
ocular by a touch.
Full descriptive Booklet and Price List on application.
R.&J.BEGK,L'^.'68Gornhill,London,E.G.
DENT'S CLOCKS
WATCHES AND CHRONOMETERS
FOR SCIENTIFIC USE.
Sidereal op Mean Time Clocks for Observatories, £21 and up>vards<
THREE GRAND PRIZES AND ONE GOLD MEDAL
FRANCO -BRITISH EXHIBITION.
The only Grand Prize awarded to a British Firm for Watches, Clocks and Chronometers.
The only Qrand Prize awarded for Astronomical Regulators, Chronographs, and 5hip's Compasses.
TRADE MARK
61, STRAND, and 4, ROYAL EXCHANGE, LONDON.
Telephone So. 61 City.
ADVERTISEMENT RATES.
Whole Page £6 6 O.
Half Page 3 S O
Quarter Page 1 15 oK,'
One-Eighth Page 0 18 6'kj
One Sixteenth Page O 10 OS;
Pep Inch, Narrow Column O 7 Ol
Half ,. „ „ O 4 0-'
Discounts for Series of Insertions and Rates for Special Positions, when
Vacant, on application to The Advertisement Manager, Knowledge Olfice, Avenue Chambers, Bloomsbury Square, London. W.C.
BEST COCOA I
SCHWEITZER'S
EARTH.;
GUARANTEED ABSOLUTELY PURE^OLUBLECOCOAONLY.
l#M
'^^.
■>v
B'
•#*
iw^:jr^^^ :>-J
KNOWLEDGE.
February, 1915,
NEW MODEL
FS and FFS
{auscli"'|omb
MICROSCOPE
WITH SAFETY SIDE FINE ADJUSTMENT.
|
Objectives. |
Eye- pieces. |
NOSEPIECES. |
Abbs comdbhser. |
|||
|
Catalogue No. |
Dry. |
OU Im- mersion. |
Price. |
|||
|
£ s. d. |
||||||
|
FS 1 |
16 mm 4 mm |
— |
7-5 X |
|
6 5 0 |
|
|
FS 2 |
16 mm 4 mm |
|
7-5 X |
Circular Double |
|
7 1 6 |
|
FS 3 |
16 mm 4 mm |
— |
5x lOx |
|
6 11 0 |
|
|
FS 4 |
16 mm 4 mm |
|
5x lOx |
Circular Double |
|
7 7 6 |
|
FFS 6 |
16 mm 4 mm |
|
5X lOx |
>. >t |
1-20 N.A. |
8 15 0 |
|
FFS 8 |
16 mm 4 mm |
1-9 mm. |
5x lOx |
Circular Triple |
1-20 N.A. |
14 0 0 |
NEW ATTACHABLE MECHANICAL STAGE, No. 2116. £3 5 0
We have sold over 100,000 Microscopes, which are in use all over the world.
Inspection invited at our New Siiowrooms, or List "A. 5. 2'* sent post free.
N.B ALL OUR INSTRUMENTS BEING MADE AT OUR OWN
FACTORY IN ROCHESTER, N.Y., THERE WILL BE NO DELAY IN DELIVERY, AND WE HAVE JUST RECEIVED LARGE STOCKS.
Trade jMakk.
BAU8CH & LOMB OPTICAL CO., 37-38 Hatton Garden London, E.G.
Op through all Dealers.
JAMES SWIFT & SON,
Optical anil Soientific Instrument Makers,
Cotitractors ta all Scientific Departments of H.M. Govt.
Grands Prix, Diplomas of Honour, and Gold Medals at London, Paris, Brussels, &c.
m"oI!l"I.M^TICROSGOPE
SPECIALLY DESIGNED FOR
BACTERIOLOGY AND HEMATOLOGY.
With Improved Fine Adjustment and Special
Mechanical 5tag:e.
Fitted with s-m., \-in., and I's-in. (Oil Immersion)
Objectives, Oculars, Triple Dust-proof Nose-piece,
Abbe Condenser, Ins Diaphragm, Mechanical Stage,
etc., in Cabinet, £23.
N£. — AU oor Microscopes (inclnding the Lenses) are made in our own workshops on the Premises.
Catalogue Post Free.
UNIVERSITY OPTICAL WORKS, 81, Tottenham Court Road, LONDON, W.
Microscope Slides.
BOTANY - ZOOLOGY - GEOLOGY.
LARGE STOCK IN ALL BRANCHES. SELECTIONS SENT ON APPROVAL.
Special Slides mounted to order from Customers' own Material.
— PHOTOMICROGRAPHY. —
CATALOGUE "A" FREE ON APPLICATION.
FLATTERS & GARNETT, Ltd.,
309, OKFORD ROAD ("SS*;;-), MUNCHESTEB.
THE "PEANDAR" ELECTRIC SELF-RECORDING ANEMOMETER
Showing inside Ihe house (from any dis- tance), on the dial, the total miles of wind passed, and on the chart a weehly record of the periodical variations.
Special contacts have been devised which pre- vent the current being left on at any time.
PRICE COMPLETE, witti wire, batteries, ink, and charts for a year, in handsome oak. mahogany, or walnut case, with bevelled plate glasses,
£22
Easily Fixed by
any Mechanic.
--s: PASTORELLI & RAPKIN, LTD.. -"
Contractors to H.M. Government, 46, HATTON GARDEN, LONDON, E.G.
ACTUAL MAKERS OF ALL KINDS OF METEOROLOGICAL INSTRUMENTS.
IW Write ior Illustiated Descriptive Lists of Standard, Self-Registering, and Self-
Recording Instruments, post free. ^fc.' 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. — February, 1915.
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KNOWLEDGE.
February, 1915.
EW MODEL
FS and FFS
(ausdi"'|omD
MICROSCOPE
WITH SAFETY SIDE FINE ADJUSTMENT.
|
Objectives. |
Eye- pieces. |
NosEPmcES. |
Abbe cohdensbb. |
|||
|
Catalogue No. |
Dby. |
Oillm- meisioD. |
||||
|
FS 1 FS 2 FS 3 FS 4 FFS 6 FFS S |
16 mm 4 mm 16 mm 4 mm 16 mm 4 mm 16 mm 4 mm 16 mm 4 mm 16 mm 4 mm |
1-9 mm. |
7-5 X 7-5 X 5X lOx 5X lOx 5x lOx 5x lOx |
Circular Double Circular Double Circular Triple |
1-20 N.A. 1-20 N.A. |
i 5. d. 6 5 0 7 1 6 6 11 0 7 7 6 8 15 0 14 0 0 |
f^EW ATTACHABLE MECHANICAL STAGE. No. 2116. £3 S 0
We have sold over 100,000 Microscopes, which are in use all over the world.
Inspection invited at our New showrooms, or List "A.S. 2" sent post free.
N.B ALL OUR INSTRUMENTS BEING MADE AT OUR OWN
FACTORY IN ROCHESTER, N.Y., THERE WILL BE NO DELAY IN DELIVERY, AND WE HAVE JUST RECEIVED LARGE STOCKS.
Trade .Mask.
BAU8CH & LOMB OPTICAL CO., 37-38 Hatton Garden London, E.G.
Or through all Dealers.
JAMES SWIFT & SON,
Optical and Scientific Instrument Makers,
Cmtractors to all Scientific Departments o/ H.M. Ccri't.
Grands Prix, Diplomas of Honour, and Gold .Medals at London, Paris, Brussels, *c.
NEW MODEL
"IJ.S/'IVIICROSGOPE
SPECIALLY DESIGNED FOR
BACTERIOLOGY AND H.«MATOLOGY.
With Improved Fine Adjustment and Special
Mechanical Stage.
Fitted with s-in., l-in., and 1*3-111. (Oil Immersion)
Objectives, Oculars, Triple Dust-proof Nose-piece,
Abbe Condenser, Ins Diaphragm. Mechanical Stage,
etc., in Cabinet, £23.
I N3. — All our Microscopes (mclodtQg the Lenses; are made in oar own ! workshops on the Premises.
Catalogue Post Free.
UNIVERSITY OPTICAL WORKS, 81, Tottenham Court Road, LONDON, W.
Microscope Slides.
BOTANY - ZOOLOGY - GEOLOGY.
LARGE STOCK IN ALL BRANCHES. SELECTIONS SENT ON APPROVAL.
Special Slides mounted to order from Customers' own Material.
— PHOTOMICROGRAPHY. —
CATALOGUE "A" FREE ON APPLICATION.
FLATTERS & GARNETT, Ltd.,
309, OXFORD ROAD (te'i";;;"). MANCHESTER.
THE "PEANDAR" ELECTRIC SELF-RECORDING ANEMOMETER
Showing inside the house (from any dis- tance), on the dial, the total miles of wind passed, and on the chart a weekly record of the periodical variations.
Special contacts hare been devised which pre- vent the current being left on at any time.
PRICE COMPLETE, witb wire, batteries, ink, and charts lor a year, in baudsome oak, mahogany, or walnut case, with bevelled plate glasses,
£22
Easily Fixed by any Mechanic.
ESTAB. 17S0.
--S PASTORELLI & RAPKIN, LTD.
Contractors to H.M. Qovernment,
46, HATTOM GARDEN, LONDON, E.G.
ACTUAL MAKERS OF ALL KINDS OF METEOROLOGICAL INSTRUMENTS.
IW Wri*e for niustiated Descriptive Lists oJ Standard, Seli-Registering, and Sell- Recording Instrainents, 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 UKbridge.— February, 1915.
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■lors to '•
firanils
Met
NEW ' MODEL
si-
BAOTE With imp
Fitted wi*' Obiective^ ^bbe Cona
WORKS, 81, Totte.
^icroscopt
ZOOLOGY
Special
,,.oK STOCK ;«/^;;
SELECTIONS SENT
S,,.esn,ounteatooraertron.^
PHOTOMICROG
-— '^" ,^ ..ft,. FBee ov
CATA1.0G0E__*__
309. OXIORORO^^U^ '
'ptmud foi Ae
Ym^-^' «»^ »^- «
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KNOWLEDGE.
February, 1915.
NEW MODEL
FS and FFS
pauscK'lomb MICROSCOPE
WITH SAFETY SIDE FINE ADJUSTMENT.
|
Catalogue No. |
Objectives. |
Eve- pieces. |
NOSEPIECBS. |
Abbe condensek. |
||
|
Dry. |
OUIm- mersion. |
Price. |
||||
|
i s. d. |
||||||
|
FS 1 |
16 mm 4 mm |
— |
7-5 X |
|
6 5 0 |
|
|
FS 2 |
16 mm 4 mm |
— |
7-5 X |
Circular Double |
|
7 1 6 |
|
FS 3 |
16 mm 4 mm |
— . |
5X lOx |
|
6 11 0 |
|
|
FS 4 |
16 mm 4 mjn |
— |
5x lOx |
Circular Double |
|
7 7 6 |
|
FFS 6 |
16 mm 4 mm |
— |
5x lOx |
1-20 N.A. |
8 15 0 |
|
|
FFS 8 |
16 mm 4 mm |
1 -9 mm. |
5x lOx |
Circular Triple |
1-20 N.A. |
14 0 0 |
KEW ATTACHABLE MECHANICAL STAGE. No. 2116, £3 S 0
We have sold over 100,000 Microscopes, which are in use all over the world.
Inspection incited at our New Showrooms, or List "A.S. 2" sent post free.
N.B.— ALL OUR INSTRUMENTS BEING MADE AT OUR OWN FACTORY IN ROCHESTER, N.Y., THERE WILL BE NO DELAY IN DELIVERY, AND WE HAVE JUST RECEIVED LARGE STOCKS.
Trade Mark.
BAUSGH & LOMB OPTICAL CO., 37-38 Hatton Garden London, E.G.
Or through all Dealers.
JAMES SWIFT & SON,
Optical and Scientific Instrument Makers,
Cofiit-actoJS to all Scientific Pcpa> ti'rents c/ H.M. Gffft.
Grands Prix, Diplomas of Honour, and Gold Medals at London, Paris, Brussels, &c.
NEW ((
MODEL
I.M.S.'MIGROSGOPE
SPECIALLY DESIGNED FOR BACTERIOLOGY AND HiEMATOLOGY.
With Improved Fine Adjustment and Special Mechanical Stage.
Fitted with s-in., |-in., and 1'5-iii. (Oil Immersion) ■^ Objectives, Oculars, Triple Dust-proof Nose-piece, ^ Abbe Condenser, Ins Diaphragm. Mechanical Stage, etc., in Cabinet. £23.
N3. — All oar Microscopes (including the Lenses) are made in oor own workshops on the Premises.
Catalogue Post Free.
UNIVERSITY OPTICAL WORKS, 81, Tottenham Court Road, LONDON, W.
Microscope Slides.
BOTANY - ZOOLOGY - GEOLOGY^
LARGE STOCK IN ALL BRANCHES. SELECTIONS SENT ON APPROVAL.
Special Slides mounted to order from Customers' own Material.
— PHOTOMICROGRAPHY. —
CATALOGUE
FREE ON APPLICATION.
FLATTERS & GARNETT, Ltd.,
309, OXFORD ROAD ('SESi,';"), MANCHESTER.
THE "PEANDAR" ELECTRIC SELF-RECORDING ANEMOMETER
Showing inside the house (from any dis- tance), on the dial, the total miles of wind passed, and on the chart a weehly record of the periodical variations.
Special contacts have been devised which pre- vent the current being left on at any time.
PRICE COMPLETE, with wire, batteries, ink, and charts lor a year, in baodsome oak, mahosany, or walant case, with bevelled plate glasses,
£22
Easily Fixed by any Mechanic.
M-- PASTORELLI & RAPKIN, LTD., "-
Contractors to H.M. Government,
46, HATTOM OARDEM, LONDON, B.C.
ACTUAL MAKERS OF ALL KINDS OF METEOROLOGICAL INSTRUMENTS.
IV Wri^e for Illustrated Descriptive Lists of Standard, Self-Registering, and Self-
Recoiding Instroments, 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.— February, 1915.
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