JUNE 27, 1912] 
NATURE 
443 
beneath low-water level. This and other evidence 
seems to show that the “‘moorlog” in this part of 
the North Sea rests upon a bed of shelly silt, and 
the shells in the silt, together with the ‘‘moorlog,” 
point to great changes of level in the North Sea 
Basin. 
Mineralogical Society, June 18.—Dr. A. E. H. Tutton, 
vice-president, in the chair.—T. V. Barker: The iso- 
morphism of the acid tartrates and tartar-emetics of 
potassium, rubidium, and cesium. The corrections 
of previous measurements of the three acid tartrates 
have been confirmed, and in addition the molecular 
volumes have been calculated; the properties of the 
three salts are found to exhibit a regular progression 
in order of molecular weight. Solutions of czsium 
tartar-emetic on evaporation yield syrups which re- 
fuse to erystallise, even when inoculated with a frag- 
ment of a salt presumably isomorphous with it. The 
rubidium salt, however, affords good crystals, which, 
contrary to previous observations, yield measurements 
almost identical with those of the corresponding thal- 
lium and ammonium salts, and fairly close to those 
of the potassium salt; there is therefore every indica- 
tion that this group of salts presents relationships 
similar to those obtained by Tutton in the sulphate 
and selenate series. The eutropic character of 
potassium, rubidium, and casium compounds was 
discussed in detail, and it was shown that not only 
the cases in which they exhibit isomorphism, but also 
those in which isopolymorphism is met with, unmis- 
takably point to the intermediate position of rubidium. 
—W. F. P. McLintock and T. C. F. Hall; The topaz 
and beryl from the granite of Lundy Island. The 
granite consists essentially of quartz, orthoclase, 
albite, biotite, and muscovite, cordierite and garnet 
also being present. Well-shaped crystals of topaz and 
beryl line druses in the granite, and are associated | 
with tourmaline, fluor, and apatite. The felspar of 
the druses is frequently kaolinised, and the orthoclase 
has in every case been affected first. It is suggested 
that carbonic acid was the principal agent in effecting 
the change, and that the alkaline carbonates produced 
attacked the topaz, the crystals of which are in- 
variably etched, and are sometimes altered to a white 
secondary mica; the formation of the fluor is ascribed 
to the same period. R. H. Solly: The rathite group. 
The characters of the members of the group were 
discussed, and the similarity of angles in the prism 
zone was pointed out.—Dr. G. T. Prior : The minerals 
of the El Nakhla el Baharia meteorite. This meteoric 
stone consists of a fairly coarse-grained aggregate of 
green augite, a highly ferriferous brown olivine, and 
a little interstitial felspar. The augite, which con- 
stitutes about three-quarters of the stone by weight, 
has a chemical composition approximating to a 
formula 3CaSiO,.2MeSiO..2FeSiO,, a mean refrac- 
tive index 1°685, double refraction 0'035 about, and 
optic axial angle 2E=89°. The olivine closely ap- 
proaches. hortonolite, except that it contains no man- 
gzanese; it has a chemical composition represented 
by the formula 2Fe,SiO,.Mg.SiO,, a mean refractive 
index 1785 about, double refraction o*o50 about, and 
optic axial angle 2V=67°.—J. B. Scrivenor: Note on 
the occurrence of cassiterite and striiverite in Peralk. 
The extent of the occurrence of striiverite was dis- 
cussed, and specimens illustrating uncommon occur- 
rences of tin-ore were exhibited and described. 
Paris. 
Academy of Sciences, June 17.—M. Lippmann in the 
chair.—G,. Bigourdan : A proposal relating to a general 
catalogue of nebulz and star clusters, and various 
questions relating to this proposal._Emile Picard : 
The developments of Cauchy in exponential series 
NO. 2226, voL. 89} 
| of the blood of A. 
and on the transformation of M. André Léauté.—E. L. 
Bertin: The use of values in the ventilation of ships. 
—Armand Gautier and Paul Clausmann: The deter- 
mination and colorimetric estimation of minute quan- 
ties of fluorine. A detailed description (with dia- 
grams) of an apparatus for determining with precision 
fluorine in quantities from o'r to 2°0 milligrams.—H. 
Douville: An attempt at the phylogenic classification 
of the Lamellibranchs.—A. Perot : The apparent moye- 
ment of vapours in the solar atmosphere. Data con- 
cerning the C and F hydrogen lines, and the calcium 
line A=6122.—Emile Borel: The theory of the 
logarithmic potential—N. Lusin: The properties of 
measurable functions.—C. Carathéodory : The general 
theorem of M. Picard.—Henri Villat: The change of 
orientation of a given obstacle in a fluid current.—G. 
Millochau: Contribution to the study of dielectric 
effects in gases.—H. Malosse: The determination of 
the density of camphor by means of the densities of 
its solution in different liquids. By extrapolation 
from the densities of solutions of camphor of varying 
concentration in ten solvents, the value of 0'963 was 
found for the density of camphor in solution.—V. 
Auger: The alkaline periodates. A criticism of some 
conclusions of Garzarolli-Thurnlackh.—F. Dienert : 
The use of physico-chemical volumetric methods in the 
estimation of the mineral constituents of waters.— 
P. Mahler and E. Goutal: The use of oxygen under 
pressure for the determination of the total carbon in 
ferro-alloys. The method of direct combustion of 
iron and steel in compressed oxygen, described by the 
authors in a previous communication, has been suc- 
cessfully extended to alloys of iron with manganese, 
silicon, chromium, tungsten, vanadium, molybdenum, 
aluminium, and titanium.—G. Vavon: The catalytic 
addition of hydrogen to benzylidene-acetone.—Jules 
Frézouls: Some derivatives of hexahydrobenzoic alde- 
hyde.—J. Pouget and D. Chouchak : ‘The influence of 
the concentration of solutions of food substances on 
their absorption by plants.—P. Mazé: Researches on 
the relations between the plant and the nutritive 
elements of the soil. The law of the minimum and 
_ the law of the physiological ratios.—A. Magnan: The 
_ yield of eggs in ducks submitted to four different 
modes of feeding. The diets included meat, fish, 
insects, and vegetables, the number and weight ot 
eggs being noted. Both the number and weight of 
eggs produced by a purely vegetarian diet were in- 
ferior to those produced by a meat or fish diet.—H. 
| Bierry and Mlle. Lucie Fandard ; Glycemia and animal 
temperature.—F. Le Cerf: Organs of adaptation in 
the adults of certain Lepidoptera.—M. Bounhiol : The 
determination of the age of the Algerian sardine. 
The ratio of the length of the body to the head length 
is utilised—E. Vasticar: The existence of a double 
external fibre in Costi’s organ.—N.-A. Barbieri: The 
colouring matter of volk of egg or ovochromine.—J. 
Riban : Ambreine.—Mlle. E. Peyréga: Spectrography 
piscatorum.—Mme. and M. Victor 
Henri: The stimulation of organisms by the ultra- 
violet rays.—Em. Bourquelot and M. Bridel: The syn- 
thetical action and hydrolysing action of emulsin in 
alcoholic solution. Emulsin determines the combina- 
tion of glucose and alcohol, 8-ethyl glucoside being 
formed.—Stanislas Meunier: Two French meteorites 
recently received at the museum, the fall of which 
passed unnoticed.—Pierre Bonnet: The Permian and 
Trias of Daralagéz.—Ph. Négris: The age of the 
crystalline formations of Attica.—A. Boutaric and G. 
Meslin: The influence of the solar eclipse of April 17, 
1912, on the propagation of electrical oscillations.— 
M. de Montessus de Ballore : The seismogenic influence 
of epirogenic movements.—J. Deprat : The succession 
of horizons of the lower and middle Trias in North 
Annam. 
