572 
NATURE 
[ April 12, 1883 
red and the green blind must be at two quite determinate poiuts 
of the spectrum. As the experiments have yielded a different 
result in persons, two of whom were red-blind, and seven green- 
blind, Dr. Konig believes that the essence of colour-blindness 
consists not in the absence of one curve, but in the displacement 
of two curves on one another, which may be more or less com- 
plete, and so preduces the different degrees of colour-blindness 
o'served. In the second investigation Dr. Konig sought to 
determine the two remarkable points of section of the three 
curves that occur, according to the Young-Helmholtz theory, in 
normal colour-perception. From the researches of Prof. von 
Helmholtz on the wave-lengths of the complementary colours, 
and from those of Clerk Maxwell on colour-mixtures, appear 
values for these points of section which agree pretty well. The 
same values, approximately, are reached by the researches of 
several ophthalmologists on the places of quickest change of 
colour in the spectrum. Dr. Konig tried to determine the first 
section point by making the violet curve disappear through the 
taking of santonin, and when he had thus made himself tempo- 
rarily violet-blind, he determined his neutral point, the point of 
section of the red and the green curve. All these determina- 
tions and theoretical considerations led to pretty much the same 
values for the points of section, and the first point is situated 
not, as is often suppose@, in the yellow, but in the blue, between 
the Fraunhofer lines E and 4,, and nearer the latter. 
Paris 
Academy of Sciences, March 26.—M. Blanchard in the 
chair.—The following? papers were read:—On an objection 
of M. Tacchini relative to the theory of the sun in the Memorie 
dei spettroscopisti Italiani, by M. Faye. Having observed the 
eruptions accompanying a spot to be intermittent and of brief 
duration, M. Tacchini thinks this fact against the theory of the 
spots being due to cyclonic movements. M. Faye says this is as 
if, on seeing the water-jet of a force-pump go down, one main- 
tained that the ;} ump did not exist.—Contribution to the study 
of stamping and of the “‘prows” it produces, by M. Tresca.— 
On the motion and deformation of a liquid bubble which rises 
in a liquid mass of greater density, by M. Resal.—Note on the 
preparation of oxide of cerium, by M. Debray.—On the reading 
of a report by M. d’Abbadie on his transit expedition to the 
island of Haiti, the president expressed the felicitations of the 
Academy (concern had been felt on account of the prevalence of 
yellow fever).—Addition to preceding communications on con- 
tinuous periodic fractions, by M. de Jonquieres.— Character by 
which one may perceive if the operation indicated by 
2t 
a Vu 6 /wi, or by / 4 £6 Vowi, 
may be effected under the forma Vo+ BN wi, m designating a 
positive whole number, v and w positive rational numbers, and 
aand 4, a and £ any rational numbers ; method of effecting this 
operation, by M. Weichold.—On a spectroscope with inclined 
slit, by M. Garbe. He described to the French Physical Society 
on March 2 an arrangement similar to M. Thollon’s. —Observa- 
tion on the figures of consumption of zinc given by M. G. 
Trouvé for his bichromate of potash batteries, by M. Regnier. 
He points out a difference between the effective and the theo- 
retical expenditure.— Heat of formation of glycolates, by M. de 
Forcrand.—Action of sulphur on oxides, by MM. Filbol and 
Senderens. Sulphur acts on alkalies in the dissolved state less 
and less easily the greater the dilution.—On the action of dif- 
ferent varieties of silica on lime water, by M. Landrin. Hy- 
draulic silica, gelatinous silica, and soluble silica absorb lime 
water more or less rapidly, but in all cases the absorption finally 
varies, for one equivalent of silica, between the limits 36 and 
38. The formula 3Si0,,4CaO, requiring for 30 of silica 37°3 of 
lime, thus fairly expresses the limit towards which those pheno- 
mena tend.—On the hydrate type of neutral sulphate of alumina, 
by M. Marguerite-Delacharlonny.—On the production of brom- 
ised apatites and Wagnerites, by M. Ditte.—Researches on 
crystalline phosphates, by MM. Hantefeuille and Margottet.—On 
various effects of air on beer yeast, by M. Cochin, Itis only some 
time after the glucose solution has penetrated, by endosmose, the 
membranous envelope of the yeast cells, that fermentation com- 
mences. Sometimes (yeast aérated) the sugary liquid simply 
penetrates into the yeast, the proportion of sugar outside con- 
tinuing undiminished ; sometimes (yeast deprived of air) the 
sugar is absorbed in larger quantity by the yeast and the liquid 
outside impoverished. It is within the cell that the sugar is 
transformed. Probably air attenuates ferments as it does virus. 
—Determination of extractive matters and of reducing power of 
urine, by MM. Etard and Richet. This determination is made 
with bromine ; which in acid solution attacks the uricacid and the 
extractive matters, The reducing power of urine varies much in 
different individuals, but little in one individual.—The percep- 
tion of colour and the perception of form, by M. Charpentier. 
Luminous rays have two distinct actions on the visual apparatus 
—one gives rise to the rudimentary perception of light and is 
distrib ted pretty equally over all points of the retina ; the other 
is more efficacious on the centre of the retina, giving rise, on the 
one hand, to the sensation of colour, on the other to the 
distinction of multiple luminous points.—Note on the adherence 
of a frontal tumour with the yolk, observed in a cassowary which 
died in the egg at the moment of hatching, by M. Dareste.— 
New observations on the dimorphism of Foraminifera, by MM. 
Munier-Chalmas and Schlumberger.—Attempt at application of 
M. Faye’s cyclonic theory to the history of primitive meteorites, 
by M. Meunier. He considers that chondrites are to rocks of 
gaseous precipitation what iron grains, &c., are to rocks of 
aqueous precipitation. They testify to eddies in the generating 
medium, to photospheric cyclones.—On shocks of earthquake 
observed in the department of La Mayenne, by M. Faucon. 
These were felt about 3 p.m. on March 8. Three considerable 
trepidations occurred in a few seconds. —M. Decharme described 
a method of preserving and reproducing crystalline forms of 
water. <A horizontal glass plate at a low temperature is covered 
with a thin layer of water mixed with minium; particles of the 
minium are involved in the formation of ice. Ulterior fusion 
and evaporation leave the minium in position. 
VIENNA 
Imperial Academy of Sciences, February 15.—C. v. 
Ettingshausen, contributions to the knowledge of the Ter- 
tiary flora of Australia.—F. Brauer, to nearer knowledge 
of the Odonate, genera Orchithemis, Lyriothemis, and 
Agrionoptera.— On the systematic position of the genus 
Lobogaster, Pil., by the same.—S. Tolver Preston, a dy- 
namic explanation of gravitation.—On the possibility of ex- 
plaining past changes in the universe by the action of natural 
laws now active, by the same.—E. Heinricher, contributions to 
the teratology of plants and morphology of flowers.—P. Pastro- 
vich, on Reichenbach’s picamar ; on ccerulignol, Reichenbach’s 
oxidating principle-—A. Tarolimek, on the relation between 
tension and temperature of saturated vapour. 
March 1.—W. Biedermann, contributions to general nerve 
and muscle physiolozy (eleventh communication) ; on rhythmic 
contractions of striped muscles under the influence of constant 
currents. —V. Graber, fundamental experiments on the light and 
colour sensibility of eyeless and blinded animals.—P. R, Hand- 
mann, on a very useful filling of the zinc-carbon battery. 
CONTENTS PacE 
Tue VivisEcTION Birt. . . - . « - 549 
Tue BritisH Navy. By W. H. WuiTe. 549 
Our Boox SHELF:— 
Baillie-Giohman’s ‘‘ Camps inthe Rockies” . 55r 
Eckardt’s ‘‘ Physics in Pictures’’ . ong 55t 
LETTERS TO THE EDITOR :— 
Unprecedented Cold in the Riviera—Absence of Sunspots.— 
CS BAWiILreraAMs: 7 551 
Mr. Grant Allen’s Article cn “The Shapes “of Leaves.”—F. O. 
Bowkk; GRANT/ALEEN 0) 0) - +22 5 as) >) os le | i 
Ticks.—Dr. T. SPENCER CoBBoLp, F.R.S. ; Rev. L. BLoMEFIELD 552 
Helix p.matia, L.—Rey. L. BLoMEFIELD . + ot Ser ase 
Braces or Waistband ?—N. . . « - - e - + » = = = 553 
Sotar RapIATION AND GLaciER Motion. By Rev. A. IRVING . . 553 
DepuctivE Biotocy, By W. T. THIse-ton Dyer, C.M.G., F.R.S. 554 
Tue AprroacuinG Ectipse (With [llustration) . a tale on coh 
DEATHS FROM SNAKE Bite 1N Bombay. By Sir JosepH FayRrer, 
K.C:S.1., F2R:S: BREE A ee eee 
AsTRONOMICAL PHotroGrapHy. By Epwarp C. PickerinG, Director 
of the Harvard College Observatory. .. . - -.- ++ + + 550 
Darwin AND Corernicus. By Prof. E. Du Bors Reymonp . . . 557 
SincinG, SPEAKING, AND STAMMERING, III. By W. H. Stone, 
M.B., F.R.C_P. ar olpns ini eo Gol otis ease 
DistTriBUTION OF ENERGY IN THE SPECTRUM. By Lord RayYLeiGu, 
F.RS. . ee ee ict to eee, oe orm ecko Sa Ea 
THE ORNITHOLOGIST IN SIBERIA (With Idlustrations) . 560 
Tue Bacicius oF TUBERCLE - ET ee ts, het Gute ene OS 
Pxoressor H. J.S.SmiTH AND THE REPRESENTATION OF A NUMBER 
ASA. SUM OF SQUARES) 4s)" «)(ciow Poms, Mel an hist) oy (ouisipines RO, 
Itong: SP Ed ee ee ono ka) eine a 6 oO Sal Ste AG 
Our AsTRONOMICAL CoLUMN:— 
D"Arrest?s Comet’! 30k) st = eg ee tee el ees ee Soy 
The Solar Eclipse in May. . . sitet Mek eyed eee AL) ae Oe 
Puysics 1n Russia DURING THE Last TEN YEARS . 567 
Socizt1gs AND ACADEMIES. Seas toe OM DMD ORL Ey Chat) 
