January 28, 1897 | 
NAT 
URE 
A 
599 
finely divided blue gold suspended in the yellow solution. — 
Note on a new meteorite from Sacramento Mountains, Eddy | 
County, New Mexico, by W. M. Foote. This was seen to fall 
in 1876. It weighs 237 kgr., and measures about 80 x 60 x 20 
cm.» It contains 91°39 per cent. of iron, and shows splendid 
etching figures. 
Bulletin of the American Mathematical Society (December 
1896).—Dr. W. J. A. Young reviews the ‘‘ Introduction a 
l'étude de la Théorie des Nombres et de I’ Algébre supérieure,” by 
Messrs. Borel and Drach, This is an interesting work founded on 
lectures by M. Jules Tannery. These lectures were delivered 
during the scholastic, year 1891-2, before the students of the 
third year, in the Ecole Normale Supérieure. Dr. Young 
characterises it as a book to be read and not to be used as a 
book of reference. The scanty table of contents offers but little | 
assistance to one, who, without having read the book, or at 
least having familiarised himself with the details as to its con- 
tents, wishes to consult its pages on a specific question. It 
gives clear and concise outlines of general principles stripped of 
illustrations and amplification. One great blemish appears on 
the surface, for hardly any references are said to be given 
either to the original sources of the material used, or as guides 
to those who wish to study the subject further. Some of the 
references which are given are not as clear as could be wished : 
thus the proof of the proposition that every integer can be 
expressed as the sum of four or fewer squares, which is based 
on the properties of continued fractions, and which makes use of | 
determinants, is assigned to Mr. Smith. To those who know 
‘this is, of course, the proof by Prof. Henry Smith. To add to | 
the unsatisfactorineéss, no indication is given of the way in which 
“* Mr. Smith” expressed his proof. Many such blemishes (appa- 
rently) are to be met with, which mar a book of considerable 
value.—‘‘ Quaternions” is a highly commendatory notice of 
Prof. Hathaway’s *‘ Primary Quaternions,” by Prof. J. B. Shaw. 
—Prof. Hathaway briefly discusses three recent text-books : viz. 
“* Elements of Geometry,” by G. C. Edwards ; *‘ Plane and Solid | 
Geometry,” by W. W. Beman and D. E. Smith; and “ Plane 
and Solid Geometry ” (suggestive method), by C. A. Van Velzer. 
Each book appears to embody some new and distinctive | 
features.—Dr. G. A. Miller, in an article on several theorems | 
of operation groups, continues his work on the lines of his 
recent contributions to the Quarterly Journal of Mathematics 
(vol. xxviii. ).—‘* Numerically regular Reticulations upon Sur- 
faces of Deficiency higher than 1” is a short note on a generalisa- 
tion of Euler’s relation for convex polyhedra, by Prof. H. S. 
White. —The usual interesting news, under notes and publications, 
closes the number. 
Wiedemann’s Annalen der Physik und Chemte, No. 1.—On 
the theory of stationary electric waves along wirés, by P. 
Drude. Electric waves are not totally reflected by a bridge 
laid across the wire system. They undergo a displacement of 
phase and a diminution of amplitude, which depends essentially 
upon the ratio of the length of the bridge to that of the wave. 
Short waves, like those in water, are greatly damped by reflec- 
tion. The absorptive power of a substance for electric waves 
may be measured by noting the number of nodes observable 
along the wire.—Treatment of high-tension accumulators, by 
L. Zehnder. The accumulators described by the author several | 
years ago must not be charged by stronger currents than o'r 
ampere per cell. The creeping up of acid along the lead may 
be prevented by spreading the plates with vaseline while hot. 
The copper wires may be similarly protected from mercury by 
burning off the latter and covering with vaseline. An important 
precaution against the deterioration of the battery is never to 
leave the cells coupled in series or single. They should be con- 
nected in parallel when not in use.— Dielectric constants at low 
temperatures, by R. Abegg. The specific inductive capacities 
of all substances increase as the temperature falls, and it is 
possible to approach the high dielectric constant of water by 
cooling other dielectrics to low temperatures.—Magnetic induc- 
tion of horizontal discs rotating in the earth’s field, by F. F. 
Martens. Describes a new method of measuring magnetic hys- 
teresis and viscosity, the disc being a limiting case of the ellip- 
soid of revolution.—Absolute thermal conductivity of air, by E. 
Miiller. Investigates all the sources of error in the vacuum- 
thermometer method, and tests the variations used by Winkel- 
‘mann and by Kundt, Warburg and Graetz. The former method | 
‘was found unsatisfactory, and the latter, which eliminates radia- 
tion by determining it absolutely z77 vacwo and deducting it, gave 
values which are too small. Taking into account the residual 
NO. 1422, VOL. 55] 
mercury vapour and the newly-determined specific heat of the 
glass employed, the author finds the conductivity of air to be 
0000056 in C.G.S. units.—An attempt to separate the two con- 
stituents of cleveite gas by diffusion, by A. Hagenbach. Dia- 
phragms of gypsum having been found unsatisfactory owing to 
contraction, compressed powdered graphite was used instead. 
The original density of the gaseous mixture being 2°315 (H = 1), 
that of the diffused gas was 2032, and of the undiffused gas 2°576. 
The author believes that he has succeeded in a partial separation 
of the constituents of cleveite gas by this means.—Diffusion co- 
efficients of some gases for water, by G. Hiifner.—Correspond- 
| ing temperatures, by J. A. Groshans.—Elasticity and light, by 
PG 
Glan, 
In the Journal of Botany for December 1896, Mr. W. A. 
Clarke completes his ‘‘ First Records of British Flowering 
Plants”; and two new species (?) of Rubus from Ireland are 
described by the Rev. W. Moyle Rogers. In the number for 
January 1897, Mr. W. P. Hiern gives a list of plants (flowering 
plants, Vascular Cryptogams, Muscinez, and Fungi) gathered in 
the Isle of Man ; Miss A, L. Smith describes some microscopic 
fungi new to or rare in Britain; Mr. J. Ll. Williams has an in- 
teresting note on the intoxicating effect produced on certain 
kinds of humble-bee by the honey of flowers belonging to the 
Compositze and Dipsacaceze. 
SOCIETIES AND ACADEMIES. 
LONDON, 
Physical Society, January 22.—Prof. Ayrton, Vice-Presi- 
dent. in the chair.—Mr. Croft gave an exhibition of some simple 
apparatus. The exhibition included an ingenious form of clip to 
fit on an upright retort stand ; a Nicol used for projecting the 
rings and brushes in crystals, with which it is sufficient to use 
the ordinary condenser of the lantern, the source of light having 
been moved further away from the lens than is usual; some 
photographs showing caustics, conical refraction, and diffraction ; 
a stand for magnets, &c., when demonstrating the attraction 
and repulsion of poles ; a stand for the suspension of objects for 
experiments on diamagnetism ; a ‘holder for X-ray tubes con- 
sisting of a spiral of wire fitting round the exhaustion tube of 
the bulb ; an X-ray photograph taken by means of a Wimshurst 
machine ; a model of Michelson’s interference experiment ; an 
arrangement to show subjective colours, in which a double lan- 
tern is arranged to give two partly over-lapping discs. A sheet 
of green glass is placed before one lantern, and the light of the 
other decreased till the illumination of the two discs is the same. 
The over-lap then appears white, while the remainder of the 
uncoloured disc appears red. Prof. Silvanus Thompson said he 
was surprised that ‘‘ patent plate” was sufficiently good for 
Michelson’s experiment. Had the author tried illuminating the 
discs, in his subjective effect experiment, fora very short interval, 
so that the eye should fot have time to wander from one disc 
to the other? Mr. Griffith said that if you looked through a 
| tube at one disc at a time, one appeared jgreen and the other 
white. The Chairman said the point seemed to be, could you 
fatigue the eye simultaneously, or must it be successive? Prof. 
Silvanus Thompson said two common t-inch microscope ob- 
jectives were very suitable for projecting rings and_brushes.— 
Mr. E. C. Baly read a paper on the passage of electricity 
through gases. In this paper, which is of a purely controversial 
nature, the author brings forward as arguments that electrical 
conduction in gases is not of an electrolytic nature the follow- 
ing : (1) That the sign of the change on the supposed gaseous 
ion is variable ; (2) the initial resistance of a gas; (3) the in- 
validity of Ohm’s law; (4) the permanence of the supposed 
gaseous electrolyte; (5) that every mixture | of gases must 
equally be an electrolyte ; (6) that the potential gradient in a 
yacuum-tube, when the current is passing, has been shown to 
It is very steep in the kathode glow, 
be very uneven. 
and is by no means a regular decline between the elec- 
trodes. Prof, Armstrong said it was difficult to know 
from what point of view the author had treated the 
question, The first part of the paper consisted almost entirely 
of acriticism of Prof. J. J. Thomson’s theory and experiments. 
Prof. Thomson, however, is not the only observer who has dealt 
with this subject. The author's arguments seemed vitiated by 
the fact that he has looked upon the subject from one very 
narrow standpoint only, viz. the ionic hypothesis, and Lord 
Kelvin, for instance, does not believe in the truth of the ionic 
