ia 
FEBRUARY 10, 1923] 



































































its application to the glass industry. Stainless steel 
ean now be made direct into castings, into sheet steel 
which is very malleable—a development of the last 
two d into tubes, so fine that hypodermic 
-needies are now largely made from stainless tubes. 
Stainless steel contains 12-14 per cent. of chromium. 
The carbon content varies a little with the different 
_types but is generally about 0-30 per cent. Stainless 
‘steels could be made use of in the glass industry on 
account of their resistance to scaling and strength at 
high temperatures. Stainless steel has a high tensile 
strength, a high fatigue range, and can be hardened and 
tempered. It might be utilised for parison and blow 
moulds ; many parts of feeder devices might be use- 
fully produced in such material, and also blowing 
jrons, rolls, belt conveyors, lehr chain pins, and other 
things, including knives for cutting viscous glass. 
The ends of blowpipes might also be made of stainless 
steel as well as wire brushes. Stainless steel is being 
used for mirrors for scientific purposes.—S. English : 
_ Some measurements of the viscosity of glasses near 
their annealing points and a critical review of some 
recent literature on the annealing of glass. Strain in 
glass cannot always be detected by using polarised 
light ; the most sensitive position is that in which 
the direction of the strain in the glass is at 45° to the 
plane of polarisation. The selenite plate is more 
sensitive than plain crossed nicols only when a very 
poor source of light is used ; it is not possible to dis- 
ish between tension and compression stresses by 
the use of such a plate. The rate of change of 
‘mobility of glasses at their annealing points is approxi- 
mately constant, most requiring a rise of temperature 
of 9° to cause a doubling of the mobility. In some 
cases this temperature interval rises to 11°. At 
-I00°-150° above the annealing points the temperature 
interval required to double the mobility was generally 
rather longer than that required at the annealing 
3 ts. The mobility of glasses is not a logarithmic 
nction of the temperature. The working properties 
of lead glasses and other soft glasses are probably 
determined more by the rate of radiation of heat than 
by rate of change of viscosity with temperature. 
o 
Paris. 
_ Academy of Sciences, January I 5.—M. Albin Haller 
in the chair.—The president announced the death of 
_M. van de Sande Bakhuyzen, corresponding member 
for the section of astronomy.—L. Lindet and P. 
Nottin: The evolution of the starch grains in the 
tuber of the potato.—W. Kilian and F. Blanchet: 
The ammonites collected by the Pourquoi-Pas ? 
Emmanuel de Margerie was elected corresponding 
member for the section of mineralogy in the place of 
the late M. CGhlert—Martin Alander: Integral 
functions which have all their zeros on a straight line. 
—G. Sagnac: The periodic variable spectrum of 
double stars: the incompatibility of the observed 
Oe eae: with the theory of general relativity.— 
. Haag: The problem of »-bodies in the theory of 
elativity.—Edouard and Rémy Urbain: The separa- 
tion of liquid mixtures by combined distillation and 
atmolysis. The preparation of practically pure ethy] 
alcohol and nitric acid. The alcohol is boiled in a 
flask fitted with a porous tube as reflux condenser. 
Round this tube is an outer glass tube in which the 
ressure is reduced. More water than alcohol vapour 
‘diffuses through the porous tube, and the alcohol in the 
flask can be strengthened to 99-8 per cent.—Ch. 
_ Bedel: A polymer of hydrocyanic acid. The crude 
polymerisation product of hydrocyanic acid is ex- 
_ tracted with ether, and the brown crystals deposited 
by this solution purified by solution in hot water and 
treatment with animal charcoal. Its composition is 
a NO. 2780, VOL. 111] 
. 
NATURE 
207 
(HCN), and appears to be aminopropanedenitrile 
hydrocyanide.—Alfred Schoep: Parsonite, a new 
radioactive mineral. This is found associated with 
chalcolite from the Belgian Congo; and has the 
composition 2PbO ..UO,;.P,0,;.H,O. It is radio- 
active.—Mlle. Germaine Cousin: The prolongation 
between Belfort and Thann of the tectonic accidents 
of the secondary border situated to the south of the 
Vosges massif—Ch. Dufour: Values of the magnetic 
elements at the station of Val-Joyeux (Seine-et-Oise) 
on January r, 1923.—Odon de Buen and José Giral : 
The hydrographic tables of Kniidsen, normal water 
and the limits of error in the analysis of sea water.— 
Louis Besson: The loss of light in Paris and its 
neighbourhood. Curves are given showing the pro- 
portion of light received at nine observing stations as 
a function of the direction of the prevailing wind.— 
G. Mangenot: The starch of the red Alge.—A. de 
Puymaly : New mode of cell division in the Desmi- 
dacee.—Emile Haas: New experiments on the 
phenomenon of Broca and Sulzer (fatigue undulation). 
—A. Goris and A. Liot: The importance of organic 
ammoniacal salts in the production of pyocyanine by 
the pyocyanic bacillus.—J. P. Aversenq, L. Jaloustre, 
and E. Maurin: Some effects of thorium-X on di- 
astases and micro-organisms. Thorium-X clearly 
increases the activity of the hydrolysing or oxidising 
properties of the enzymes studied (pyalin, amylase 
from pancreatic juice, amylase from germinated 
barley, emulsion, ammonia ferment, oxydases of the 
blood and saliva), and also increases the vitality of 
certain pathogenic organisms.—Georges Bourgignon 
and Henri Laugier: Variations of the neuromuscular 
excitability under the influence of the suppression and 
re-establishment of the circulation of a limb in man. 
WASHINGTON. 
National Academy of Sciences (Proc. vol. 8. No. 12, 
December 1922).—O. Veblen.—Projective and affine 
geometry of paths.—W. F. Hamilton: A direct 
method of testing colour vision in lower animals. 
Two Hilger wave-length spectrometers used as mono- 
chromatic illuminators were arranged to throw beams 
of light on the opposite ends of a horizontal glass 
tubular cell containing Drosophila which had been 
kept in the dark overnight. The intensities of the 
beams (of different wave-lengths) were regulated so 
that the flies showed no orientation. One beam was 
then screened for a time, and on again exposing it, the 
flies definitely moved towards it showing differential 
fatigue. The smallest difference of wave-lengths 
showing a stimulating effect was used, and over the 
range 385-500 mu, hue-perception is a maximum 
between 410 mu and 450 mu, possibly indicating 
two receptor systems, one for the blue-violet and one for 
the blue-green.—L. L. Nettleton : Characteristics of a 
short wave oscillator at very low pressures. A three- 
element tube was left permanently connected with 
the vacuum pumps, and currents up to 300 milliamps. 
at 700 volts were used. The oscillations were mea- 
sured by a crossed wire thermocouple carried on a 
bridge sliding along the Lecher wires. Oscillations of 
wave-length 50-200 cm. were obtained. Both negative 
plate current and oscillations ceased abruptly at very 
low pressures (000005 mm.) in the tube as measured 
by an ionisation manometer. The curves resulting 
from plotting the voltage at the plate and the oscilla- 
tions in the Lecher wires against the ionisation appear 
to show that some little ionisation is necessary for 
this type of oscillation, but the kind of gas present does 
not seem important.—Bergen Davis and H. M. Terrill. 
The refraction of X-rays in calcite. A water-cooled 
tube with a molybdenum target was used and measure- 
ments were made for the first three orders of the Ka, 
