6: NATURE 
[NoveMBER 26, 1896 
form, and of benzene and 
carbon bisulphide. In the 
Jatter the differences 
are very slight, and these liquids 
may be said to preserve their viscosities without appre- 
ciable change. But when the constituent liquids have very 
different viscosities, such as benzene and nitro-benzene, the re- 
sultant viscosity is lowered considerably.— Volume measurement 
of an air thermometer bulb, by W. G. Cady. This may be 
accomplished without filling the bulb with water or mercury, 
by connecting it with a short graduated tube, changing the 
volume of the combination by an amount indicated on the 
graduations, and measuring the increase of pressure.—Residual 
viscosity and thermal expansion, by H. D. Day. A bar of 
vulcanised rubber expanded until 50° was reached, and then 
suddenly contracted. On again heating after some time, it 
expanded till it reached the highest temperature at which it 
had been maintained beforehand, and then contracted again. 
This phenomenon is due to internal strain in its manufactured 
state, and to a consequent molecular settling which sets in at 
certain temperatures.—Application of certain organic acids to 
the estimation of vanadium, by P. E. Browning and R. J. 
Goodman. Describes the determination of vanadium by means 
of tartaric, oxalic, or citric acid in the presence of molybdenum 
and tungsten.—Determination of oxygen in air and in aqueous 
solutions, by D. A. Kreider. A known volume of air is con- 
ducted through a strong solution of hydriodic acid in the pre- 
sence of nitric oxide; the acid is neutralised by potassium 
bicarbonate ; and the liberated iodine is titrated with standard 
decinormal arsenic solution, from which the equivalent volume 
of oxygen is readily calculated.—Amphibian footprints from the 
Devonian, by O. C. Marsh. A genuine specimen of a foot- 
print from some vertebrate animal, apparently amphibian, has 
been found in the Upper Devonian of Pleasant, Warren County, 
Pennsylvania. This is the first evidence of life superior to the 
fishes found in that formation. The specimen is preserved in 
the Yale Museum. 
Wiedemann’s Annalen der Physik und Chemie, No. 11.— 
Rotations in a constant electric field, by G. Quincke. Rods, 
plates, spheres, or cylinders of a dielectric substance, suspended 
in a liquid dielectric between vertical condenser plates, exhibit 
slow rotations about an axis parallel or at right angles to the 
lines of force when a constant field of sufficient intensity is 
maintained between the plates. The author describes a great 
variety of experiments which exhibit this curious phenomenon. 
He explains it by the electrostatic deformation of the air film 
adhering to the bodies and producing a tangential pressure.— 
choto-electric residual action of kathode rays, by J. Elster and 
H. Geitel. Alkaline chlorides exposed to the action of kathode 
rays assume peculiar colorations, and become photo-electrically 
sensitive. At the same time their phosphorescence diminishes, 
and a bluish film resembling an alkali metal is deposited on the 
walls of the tube. The authors naturally supposed that this 
consisted of metallic sodium, potassium, ceesium, or rubidium 
due to decomposition of their respective salts by the kathode 
rays. This would account for the observed photo-electric be- 
haviour. But mercury was incapable of forming an amalgam 
with the deposit, and this explanation is therefore excluded. 
That it must be sought in a modification of the salt itself is 
shown by the fact of the photo-electric property remaining in the 
open air as long as the colour remains. Similar properties are 
possessed by colourless fluorspar, by potassium carbonate and 
glass, and to a slighter extent by calcium and barium chlorides. 
The authors think that a slight reduction takes place, and that 
the metal produced forms a solid solution in the remainder of 
the salt.—Interference refractometer for electric waves, by O. 
Wiedeburg. Describes an arrangement corresponding to 
Jamin’s refractometer adapted to electric waves. The refractive 
index of paraffin found by this method is 1°418, and of plate 
glass 2°63, with a probable error of only 1 per cent.—Helm- 
holtz’s absolute electro-dynamometer and its use in determining 
the E.M.F. of a Clark cell, by K. Kahle. The electro-dyna- 
mometer consists of a square metallic band acting upon a coil 
attached to the arm of a balance, the planes of the band and 
the coil being perpendicular to each other. The square shape 
has the advantage that only its corners need support, and the 
band allows of strong currents and simplifies calculation. The 
E.M.F. of the H-shaped Clark cell was found to be 174488 
volts at o° and 1°4322 at 15°.—The cadmium standard cell, by 
W. Jaeger and R. Wachsmuth. A Clark cell of the H-shape, 
in which cadmium amalgam is substituted for the zinc amalgam 
and cadmium sulphate for zine sulphate has an E.M.F. of 1019 
NO. 1413, VOL. 55] 
volts at 20°, It has an extremely small temperature coefficient 
(0°004 per cent., instead of o°r per cent. as in the Clark cell), 
and it is not surpassed by the ordinary Clark cell as regards 
durability and facility of reproduction.—Influence of Réntgen 
rays upon the steam jet, by F. Richarz. Since X-rays make 
air temporarily conducting, and therefore probably lead to ionic 
dissociation, they would also on that account increase the con- 
densation in a steam jet. This is actually the case, as the 
author showed by exposing a steam jet, screened from direct 
electrostatic action, to the rays traversing an aluminium window. 
—Aluminium amalgam, by V. Biernacki. This may easily be 
obtained by dipping an aluminium wire repeatedly into mer- 
cury, while each metal is connected with a pole of a battery. 
It may be kept for a long time in perfectly dry air, but in moist 
air it oxidises rapidly, forming a growth of pure alumina which 
makes an attractive lecture experiment. 
THE latest issue of the Zzvestéa of the East Siberian branch 
of the Russian Geographical Society (vol. xxvi., Nos. 4 and 5, 
Irkutsk, 1896) contains various matters of interest. It begins 
by an elaborate paper, by A. A. Kaufmann, on the complex 
forms of land tenure in Siberia. An immense mass of data 
relative to this question has lately been accumulated by the sur- 
veys and explorations which have been made in Siberia, in order 
to ascertain the area of land which remains free for the new- 
coming settlers, and the results of these elaborate researches and 
surveys were embodied in a series of volumes, published by the 
Ministry of State domains, under the name of ‘‘ Materials rela- 
tive to the economical conditions of the peasants in Siberia.” 
M. Kaufmann now sums up the results of these researches, which 
are the more important as they show what forms of land tenure 
have been developed by the immigrants themselves, who had 
been left absolutely free to occupy immense tracts of waste land, 
and to work out such forms of land tenure as they themselves 
found convenient. A very great variety of forms of land tenure 
has thus come into existence in both West and East Siberia, 
nearly all hitherto known forms of Jand tenure being represented 
on this vast area, with the exception of only one, namely the 
private, hereditary and individual ownership of the land. This 
last does not exist, while communal possession is everywhere 
the rule, and it takesa quite unsuspected variety of forms. The 
prevailing form is the possession by a group of villages, or by 
the canton or Volost, which includes from ten to fifteen separate 
villages, and usually has several thousands of inhabitants, who 
consider the land of the Volost as their common possession, and 
allot and re-allot it according to their respective needs. Within 
the estate of the Volost, again, a great variety of forms of land 
tenure is found, and very often strangers to the canton are also 
admitted to the temporary possession of parts of the Volost’s 
estate in exchange for similar rights being granted to the in- 
habitants of the Volost on the land owned by those strangers. 
On the whole, M. Kaufmann’s essay can be earnestly recom- 
mended to the attention of the students of the subject in this 
country.—Two papers, on the Buryates of Irkutsk, by P. E. 
Kulakoff, and on the Buryates of Transbaikalia, by M. A. 
Kroll, are full of interest, as the former contains valuable 
remarks on the influence of the Shamanist religion, the epi- 
demical insanity which lately prevailed in the Buryate settle- 
ments, the influence of contact with the Russians, Xe. ; 
while the second has new data upon the tribal organisation, and 
mentions the interesting fact that the Transbaikalia Buryates do 
not die out as other natives do, but have doubled their numbers 
since the beginning of this century.—Three papers, on the 
Yakutes, deal with the old tribal organisation of the Yakutes, , 
with some graves of the beginning of this century, and with 
the Yakute tales collected by the late M. Khudyakoff, and lately 
published at Irkutsk under the name of ‘‘ Verkhoyanskiy 
Sbornik.”—V. B. Shostakovich contributes a paper on the pro- 
tective adaptations of the buds in different Siberian trees and 
bushes (with one plate) ; and Prof. Katanoff gives an account of 
the Turkish inscriptions on the Orkhon and the Yenisei. 
SOCIETIES AND ACADEMIES. 
LONDON. 
Chemical Society, November 5.—Mr. A. G. Vernon Har- 
court, President, in the chair.—The following papers were 
read:—The constitution of the so-called nitrogen iodide, by 
F. D. Chattaway. The most probable formula assignable to 
es 
