568 
NATURE 
[April 12, 1883 
Society has 120 members, a capital of 1638/., a library, and a 
physical laboratory, mostly of instruments presented by M. 
Bazilevsky. As to the scientific communications made to the 
Society, they are of great value, as will be seen from the following 
brief summary. 
The first rank among them belongs to the researches of Prof. 
Mendeléeff, which are nearly all connected with his extensive 
work on the elasticity of gases, these last leading him to a 
great number of collaterai researches, and to the invention of 
new methods and instruments, Such are, for instance, his 
communications :—1. On a differential naphtha-barometer in- 
tended to show small changes of pressure. 2. On a levelling 
instrument, being a modification of the former, and eacily 
showing changes of level of one metre; it might be applied also 
to the measurement of the changes of density of air; an entire 
memoir was written by M, Mendeléeff to describe this apparatus, 
which is susceptible of so many applications. 3. On a means of 
boiling mercury in barometers. 4. On a new siphon-barometer, 
which is, so to say, a combination of two siphon-barometers 
connected together in their upper parts, one of the two tubes 
being capillary, and serving to exhaust the air which may pene- 
trate Torricelli’s vacuum, and for filling the instrument with 
mercury. 5. On a mercury pump which eliminates the disad- 
vantages of friction, 6. On a very sensitive differential ther- 
mometer. 7. On a formula of expansion of mercury from 
temperature: the volume at a temperature ¢ being = 100,000 
+ 17°99 ¢ + o7002112 7%, where 100,000 represents the 
volume at zero. 8. On the coefficient of expansion of air; the 
experiments were made with great accuracy, and the volumes 
measured by the weight of mercury; the coefficient was found to 
be a = 0'0036843. 9. On the temperature of the upper strata 
of the atmosphere; according to the measurements of Mr. 
Glaisher, Prof. Mendeléeff found that the increase of tempera- 
ture (7) is equal to the increase of pressure (7) ; that is, a 
aH 
fsa 
Const., or t= C+ A Taking, then, into account the 
0 
influence of moisture, Prof. Mendeléeff deduced, from the laws 
of the mechanical theory of heat, a formula which better agrees 
with observations than the formula of Poisson, deduced for dry 
air. An accurate knowledge of the law of changes of tempera- 
ture in the upper parts of the atmosphere having an immense 
importance for meteorology, astronomy, and cosmography, Prof. 
Mendeleéeff elaborated a thorough scheme of aérostatic observa- 
tions in Russia, 10, On a general formula for gases; instead 
of the well-known formule of Clapeyron, he proposes the fol- 
lowing, which embodies the laws of Marriott, Gay-Lussac, and 
Avogadro:—d PV = KM(C + 7), where JZ is the weight of 
the gas in kilogrammes, and 4 — its molecular weight, the 
atomic weight of hydrogen being taken as unity ; A is a constant 
for all gases, whilst the 2 of Clapeyron varies with the nature 
and mass of the gas. 11. On the compres-ibility of air under 
pressures less than that of the atmosphere ; the chief results for 
pressures from 650 millimetres to 0°5 millimetre are: the law of 
Marriott not only is not true for low pressures, but the disagree- 
ment increases as the pressure decreases; the produce PV 
(pressure multiplied by the volume), at pressures from 0°5 to 
650 millimetres, zzcreases for the air approximately from 100 to 
150, instead of decreasing, as resulted from Regnault’s measure- 
ments under higher pressures, ‘his result was so unexpected 
and so contrary to current opinion that the measurements 
were repeated many times and by different methods, but 
the result was always the same. So it must be inferred 
(to use Prof. Mendeléeff’s own words) ‘that as the rare- 
faction of gases goes on, a maximum volume, or limit 
volume, is reached, like the minimum or limit volume reached 
at compression ; therefore it cannot be said that a gas, when 
rarefied, merges into luminous ether, and that the atmosphere of 
the earth has no limits.” The rarefied gas becomes, so to speak, 
like a solid body, If the pressure on a solid is diminished its 
volume increases, but at a pressure equal to zero it still attains 
a limit volume. ‘There are many other communications of less 
importance which were made also by Prof. Mendeleeff. 
Some communications by M. Kraevich were also connected 
with the same subject. He made investigations into the degree 
of rarefaction reached in mercury-pumps ; into the luminous 
phenomena in Geissler tubes ; into the dissociation of sulphuric 
acid and glycerine in vacuum, and so on. A special interest is 
attached to his preliminary experiments on rarefied air by anew 
method, which experiments lead to the conclusion that “‘ after a 
certain limit of rarefaction the elasticity decreases much more 
rapidly than the density, and at a very great degree of rarefaction 
the air loses its elasticity.” These experiments would thus con- 
firm the researches of Prof. Mendeléeff.mM. Kraevich has 
described an improved barometrograph, a portable barometer, 
and a mercury-pump of his own invention. 
Several improvements of the barometer were proposed, too, 
by MM. Shpakovsky, Gu'kovsky, Reinbot, and others. M. 
Lachinoff has proposed a mercury-punip without cocks. To 
the same department belong also the researches by M. Rykacheff 
into the resistance of the air; by M. Eleneff, on the scefficients 
of compressibility of several hydrocarbons; by M. Srezneysky, 
on the evaporation of water-:olutions of the chlorate of zinc ; 
and by M. Schiff, on the compression of indiarubber cylinders. 
In mechanics and mechanical physics M. Hesehus notices the 
works, by M. Bobyleff, on the weighing methods of Borda and 
Gauss ; on the length of the seconds-pendulum at Kharkoff, by 
M. Osiroff, and several other communications by MM. Bobyleff, 
Schiller, Lapunoff, and Gagarin. 
Calorific phenomena were the subject of many communica- 
tions, we notice these: On the calibration of thermometers, by 
MM. Mendeléeff and Lermontoff; on the expansion of mercury 
and gases, by M. Mendeléeff; a formula of expansion of mer- 
cury and water, by M. Rosenberg; on the expansion of india- 
rubber, by M. Lebedeff; on a new method of determining the 
caloric conductibility of bodies by heating them at one end, by 
Prof. Petrushevsky ; and several communications on the critical 
temperature, by MM, Avenarius, Jouk, and Strauss. 
The communications on optics were numerous, and we notice 
among them the descriptions of an optical micrometer based on 
Newton’s rings; and of a spectrophotometer, by Prof. Petru- 
shevsky ; the very interesting researches of M. Ewald on the 
phenomena of vision ; the researches into the chemical action of 
light, by M. Lermontoff, who has tried to prove that light pro- 
duces a dissociation of molecules and a new distribution of atoms 
whose return to their former distribution produces the pheno- 
mena of phosphorescence ; several communications dealing with 
reflexion in mirrors ; several papers on spectrum analysis ; and 
researches dealing with photography. 
The communications on electricity were as numerous as all the 
others taken together, the chief of them being: On the distribu- 
tion of electricity on spheres under different conditions, and two 
other papers on electrostatics, of less importance, by M. Boby- 
leff ; on the magnetisation of fine steel cylinders, by M. Khivol- 
son, who has proposed a theory of residual magnetism, 
explaining these phenomena by the influence of molecules of 
carbon, which prevent to some extent the rotation of the mole- 
cules of iron; researches by M. Van der Flith on the mechanism 
of the interior and exterior phenomena of the current, which 
are explained by the molecular rotation in the circuit and by the 
breaking of equilibrium in the surrounding ether ; the papeis on 
thermoelectricity by Prof. Petrushevsky and M. Borgman, and 
several other papers by M. Borgman, Prof. Lenz, and Prof. 
Umoff; the microscopical researches into the crystallisation of 
the metal of electrodes, by M. Shidlovsky ; and many others 
which it would be impossible to enumerate in this note. It will 
be sufficient to mention that the number of proposed electrical 
apparatus, as well as of papers on electro-technics, was very 
great, and some of them were of great value. 
Cosmical physics was represented by most valuable papers on 
the resisting medium in space, by M. Asten; on the transits of 
Venus and Mercury, on variable and double stars, and on the 
parallax of refraction, by M. Glasenap; on the tails of the 
comets 4 and c, 1881, by Prof. Bredikhin ; and by several in- 
teresting communications of MM. Woeikoff, Mendeléeff, Ryka- 
cheff, Schwedoff, and many others. 
SOCIETIES AND ACADEMIES 
LONDON 
Royal Society, March 1.—‘‘ Contributions to the Chemistry 
of Storage Batteries,” by E. Frankland, D.C.L., F.R.S. : 
1. Chemical Reactions.—The chenical changes occurring 
during the charging and discharging of storage batteries have 
been the subject of considerable cifference of opinion amongst 
chemists and physicists. Some writers believe that much of the 
storage effect depends upon the occlusion of oxygen and hydrogen 
gases by the positive and negative plates or by the active material 
thereon ; some contend that lead sulphate plays an important 
