APRIL 4, 1912] 
NATURE 131 
MANCHESTER. 
Literary and Philosophical Society, March 19.—Prof. 
F. E. Weiss, president, in the chair.—Prof. S. J. 
Hickson: Note on a specimen of a recent coral, Endo- | A , 
c P : | during the last four winters showed that when the 
pachys grayi, from the Persian Gulf. Three out of 
the four known specimens of this species were until | 
quite recently in the possession of the Manchester 
Museum, but one has, however, been presented to the 
British Museum of Natural History. One specimen 
was reported as having been found in the China Sea. 
—C. E. Stromeyer: Note upon the surface ridges and 
hollows of tramway and railway lines.—R. F. 
Gwyther: The complete formal solution of the equa- 
tions of stress in cartesian, and in cylindrical and 
spherical coordinates. The paper dealt with the 
stresses in materials, independently of any assump- 
tion as to their nature, and so applicable to all struc- 
tural materials, such as iron, steel, and concrete, as 
well as to stresses of earth on retaining walls, and 
perhaps of grain in grain tins or bunkers. Most 
theoretical applications have been made to substances 
assumed to obey Hooke’s law connecting stress and 
strain, and also applied to substances which are cer- 
tainly not of that character. The method can be 
ppeped to the subject of geophysics.—Dr. H. G. A. 
ickling : Variation of Planorbis multiformis. The 
shell exhibited every gradation from a perfectly flat 
type to one with a high spire. 
presented by a large number of specimens, while the 
2xtreme types are scarce. The curve representing the 
various types is a simple variation curve, thus proving 
that all the forms belong to a single species. Great 
variation occurs in other characters of the shells, and 
these variations appear to be independent of one 
another. 
EDINBURGH. 
Royal Society, March 4.—Prof. T. Hudson Beare, 
vice-president, in the chair.—Dr. J. W. Evans: The 
geometry of twin crystals. The paper contained a 
somewhat novel way of considering the mathematical 
relationships in twin crystals—E. M. Wedderburn : 
Temperature observations in Loch Earn, with a 
further contribution to the hydrodynamical theory of 
temperature oscillations in lakes. With the help of 
some two dozen students of science in Edinburgh and 
Dundee, Mr. Wedderburn made a careful 
of the simultaneous temperature variations at a 
number of selected stations along Loch Earn during 
August of last year. The oscillations of the tempera- 
ture seiche could be clearly traced. At.certain stations 
measurements of current were also made. A modified 
theory gave a formula for the period of the seiche 
which agreed within 5 per cent. of the observed 
period.—James Russell: Transverse induction changes 
in demagnetised and partially demagnetised iron in 
relation to the molecular theory of magnetism. Iron 
tubes were magnetised spirally by applied longitudinal 
and circular magnetic fields, and these were reduced 
by diminishing alternations until the tube was left in 
an apparently neutral condition. The zolotropy left 
in the material was proved by the transverse induction 
change produced by application of a given field. 
These transverse changes were compared with what 
was deduced from a_ special theory of molecular 
magnetism. The comparison was satisfactory. 
March 18.—Dr. James Burgess, C.I.E., vice-presi- | 
dent, in the chair.—Dr. W. T. Gordon: Rhetinangium 
Arberi, a new type of fossil stem from Pettycur. 
This new genus and species is important on account 
of its relationship to other forms. It resembles 
Heterangium in many points, but is most closely 
allied to Kidston’s new genus, Stenomyclon. The 
new form seems to be a phyllogenetic link between 
the lower Pteridosperms as represented by Heter- 
NO. 2214, VOL. 89] 
The mean type is re- | 
study | 
angium and the higher members of that group.—Dr. 
John Aitken: The sun as a fog-producer. It was 
noticed some years ago that at Falkirk fogs fre- 
quently began to form just at sunrise. Observations 
wind was light and came from an impure direction 
(that is, from densely inhabited areas), and was damp, 
but not necessarily saturated, a fog invariably formed 
if the sun shone, but did not form if there was no 
sunshine; also that when the wind came from a pure 
direction, the sun had no fog-producing effect. Ex- 
periments were then made on vessels filled with 
various products of coal combustion, and the con- 
clusion was come to that the fogs were caused by the 
action of the sun on the products of the sulphur in 
the coal, and also to the sunshine forming hydrogen 
peroxide in the air. In this way particles are formed 
which can condense vapour in unsaturated air. 
Radio-activity and the electric discharge had a similar 
action. 
Paris. 
Academy of Sciences, March 25.—M. F. Guyon in 
the chair.—Maurice Hamy and M. Millochau : The new 
star in the constellation of the Twins (see p. 121).— 
H. Poincaré: The diffraction of the Hertzian waves. 
Remarks on a dissertation by M. March, in which 
conclusions are drawn which are in contradiction to 
those previously published by M. Poincaré. It is 
shown that this difference is due to an error in the 
method employed in the approximation of an integral. 
—A. Lacroix: The deposits of corundum in Mada- 
gascar. These deposits result from the metamorphism 
of aluminous sediments under the influence of granite ; 
their practical utilisation is doubtful owing to the 
discontinuous nature of the deposits.—W. Kilian and 
Ch. Jacob: The tectonic of the mountains situated 
between Mt. Blanc and the small St. Bernard.—M. 
Metchnikoff was elected a Foreign Associate in the 
place of the late Sir Joseph Dalton Hooker.—Fr. 
Iniguez: The new star, Nova Geminorum. Observa- 
tions made at the Observatory of Madrid. The 
spectrum showed two superimposed spectra, one with 
bright lines of hydrogen, the other an absorption 
spectrum rich in lines in the neighbourhood of Hy.— 
Ch. Platrier : Contribution to a theorem on the integral 
equations of Fredholm of the third species.—Rodolphe 
Soreau: The graphical resolution of the trinomial 
equation with any exponents.—A. Leduc: The specific 
heats of vapours in the immediate neighbourhood of 
saturation. The theoretical investigation given is 
applied to the case of water.—Louis Dunoyer: New 
observations on the fluorescence of sodium vapour. 
Details are given of the special precautions taken to 
ensure the purity of the sodium employed. The 
fluorescence obtained was yellow, and examined 
spectroscopically was found to show only the D line. 
—A. Cotton and H. Mouton: Magnetic double refrac- 
tion and chemical constitution.—Ed, Chauvenet ; The 
hydrates of zirconyl chloride. Thermochemical data 
for the hydrates of zirconyl chloride—M. Dublancq- 
Laborde: The existence of metamorphosed limestone 
blocks in the older tufa of Mount Pelée.—Pierre 
Lesage: The limits of germination of seeds submitted 
to the action of various solutions.—J. E. Abelous and 
E. Bardier: The mechanism of anaphylaxis.—Ch. 
Gravier: Some parasitic Crustacea arising from the 
second. French Antarctic expedition.—Mieczyslaw 
Oxner: Experiments on memory and its nature in a 
marine fish, Serranus scriba. The proof has been 
obtained that this fish can clearly associate the sensa- 
tion of feeding with the red colour of a cylinder in 
which the food was placed—O. Duboscq and Ch. 
Lebailly: Spirella canis, a new genera and new 
