May 26, 1923] 3 
NATURE 
137 

critical points if the objects are on the same horizon 
and one outer critical point if they are on different 
horizons. For pairs of objects any of which can be 
combined together, there are two pairs of such 
critical points. 
Royal Meteorological Society, May 16.—Dr. C. 
Chree, president, in the chair.—M. de Carle S. Salter 
and J. Glasspoole: The fluctuations of annual rain- 
fall ia the British Isles considered cartographically. 
Ps expressing annual rainfall 1868-1921 as a 
percentage of the average, fall roughly into three 
types, indicating respectively (i.) excess of oro- 
iy ees rain, (ii.) deficiency of orographical rain, 
il.) excess of cyclonic rain. The mean range of 
variation per annum is 35 per cent., with local 
extremes varying from +80 per cent. to —59 per 
cent. . In the earlier years the maxima were generally 
in the east: in the middle of the period in the west : 
and in the later years in the south. The general 
rainfall varied from 136 per cent. in 1872 to 77 per 
cent. in 1887, the deviation exceeding 20 per cent. 
in only 5 years, and averaging 8 per cent. From 
1868 to 1882 maxima occurred at intervals of 5 years ; 
from 1889 to 1909 of 3 years ; and from roro to 1921 
of 2 years. There is also evidence of a long-period 
fluctuation with two maxima about 40 years apart. 
Annual pressure maps for the same series of years 
appear to show three main types of variation due to 
(i.) shifting of the S.W. wind drift to N. or S.; 
(ii.) changes in the gradient; (iii.) local deflections 
of the isobars. Type (i.) appears to determine the 
amount of general rainfall ; type (ii.) determines the 
distribution of rainfall; type (iii.) affects both 
variables, and includes all extremely dry or wet 
years.—A. W. Clayden: An improved actinograph ; 
note on the influence of a glass shade. Two similar 
bimetallic coils, like those used for thermographs 
but with 7} turns each, are mounted about a common 
axis and attached toa recording pen, in such a manner 
that the movements of the pen register only the 
difference of temperature between the two coils. 
The axis is fixed in a position parallel to the polar 
axis with the coils at its ends. The instrument 
stands in a case so that the coil at the lower end is 
shaded from the sun, while the coil at the upper 
end is exposed under a hemispherical glass shade to 
full sunlight and is blackened. The records for five 
consecutive years from February 1914 show a rapid 
rise of radiation during January to April, a slight 
drop about the middle of May followed by a rise 
to ace and a fall during the latter half of the year 
which is notably more gradual than the vernal rise. 
—E. E. Benest: Notes on the ‘‘ Sumatras”’ of the 
Malacca Straits. These squalls usually blow from 
the south-west, and are more frequent between 
April and October. A greater number is experienced 
between Malacca and Pulo Penang than between 
Malacca and Singapore. ‘‘ Sumatras ’’ always occur 
at night, and are generally accompanied by thunder, 
lightning, and torrential rain; they seldom last 
more than two hours. The strength of the wind 
is estimated as between 40 and 55 miles per hour. 
A characteristic cloud formation is a heavy arch or 
bank of cumulo-nimbus, which rises to an estimated 
height of about 7ooo ft. and rapidly spreads over 
the whole heavens. 
Paris. 
Academy of Sciences, April 30.—M. Albin Haller in 
the chair—A. Haller and a Palfray : The mixed and 
symmetrical 1 - ethanoic - 1 -camphomethanoic esters 
and their saponification products. These compounds, 
containing both the (CH,.CO,H) and (CO,H) groups, 
attached to the same atom of the camphor molecule, 
NO. 2795, VOL. 111] 

form esters which are singularly difficult to hydrolyse. 
—A,. Calmette, A. Boquet, and L. Négre: Rdle of the 
terrain in the evolution of experimental tuberculosis 
in the rabbit and guinea-pig. The interval of time 
between the injection of tubercle culture into a 
_rabbit and the death of the animal through tuber- 
culosis has been proved to be inversely proportional 
_ to the number of bacilli inoculated, the bacilli arising 
'from the same culture. 
rabbits the number of bacilli injected appears to be 
the main factor in determining the time of evolution 
With guinea-pigs and 
of the disease, and there are no indications of a factor 
involving variable sensibility of the individual 
animals.—Georges Bouligand: The singularities of 
harmonic functions.—A. Sainte-Lagué : Networks.— 
J. Haag: The gravitational field of » bodies. A 
correction of an earlier note on the same subject.— 
Louis Roy: Gauss’s theorem of least constraint. 
This theorem of Gauss is stated to be incorrect.— 
M. Cisotti: Remarks on the note “ Superficial 
circulation ’’ by M. P. Noaillon.—F. Henroteau : 
Variations of the spectrum of the star @, Orionis. 
In addition to the absorption lines due to hydrogen 
and other elements, a photograph of the spectrum 
taken at Ottawa in 1919 and January 1920 showed 
fine, intense emission lines. These lines were not 
found by O. Struve (Yerkes Observatory) in 1922, 
but were present on a spectrogram taken March 2, 
1923. Hence this star, class B and not variable, 
shows bright lines only at intervals, a new phenomenon 
in astronomy.—Max Morand: Certain electromagnetic 
consequences of the principle of relativity.—L. 
Dunoyer: Induction spectra and spark spectra. 
Reply to a criticism by Léon and Eugéne Block.— 
S. K. Mitra: The demagnetisation of iron by electro- 
magnetic oscillations. A study of the effects of 
variation of the frequency of the alternating current 
on the residual magnetisation. The demagnetisation 
increases as the frequency of the oscillations is 
lowered.—Félix Michaud: Deformations of jellies by 
the action of an electric current. When a jelly is 
placed between two metallic electrodes, and an 
electric current is passed, it contracts towards the 
anode, and swells out near the cathode. The nature 
of the metal used for the electrodes is without 
influence. The action depends on the colloid ; 
gelose gives a more intense effect than gelatin.— 
Pierre Brémond: The persistence of the colour of 
the ions in ceramic colours or colouring materials 
obtained at a high temperature. Attention is 
directed to the fact that some of the colours shown 
by ceramic products due to metallic constituents, 
and produced at high temperatures, correspond with 
those found in the salts of the same metals, or in 
hydrates which are stable only at low temperatures. 
—Mme. and M. A. Lassieur: The estimation of 
antimony by means of phenylthiohydantoic acid.— 
Marcel Pichard: Method of analysis of cocoa butter 
and its mixtures with vegetable fats. The method 
is based on the form of the cooling curve of the melted 
fat, when allowed to solidify slowly.—L. J. Simon 
and Léon Piaux: The conversion of alanine into 
pyruvic acid by the direct action of oxygen. Alanine 
can be oxidised directly to pyruvic acid by shaking 
with oxygen in the presence of alkali and metallic 
copper, but the proportion of copper present must be 
carefully regulated (r molecule alanine to } atom 
copper) and the reaction stopped immediately the 
absorption of oxygen ceases.—M. Aloy and M. 
Valdiguié: The oxidations and reductions produced 
by uranium salts under the influence of light. The 
antioxygen effect of phenols. Uranium acetate can 
act like an oxidising-reducing ferment. A solution 
of this salt, just acid with acetic acid, when mixed 

