194 
NATURE 
[APRIL 15, 1915 

advanced students produce papers dealing with sub- 
jects of research which are accepted by leading 
scientific journals in Europe. In the past years the 
Government of India has contributed generously to 
the capital requirement of the University of Calcutta, 
which also draws an annual sum, the capitalised value 
of which is 363 lakhs, and generous gifts have been 
received recently from the late Sir Taraknath Palit 
and Dr.. Rashbehari Ghosh. In Bombay the con- 
tributions of few public-minded citizens to the pro- 
posed Royal Institute of Science have totalled nearly 
25 lakhs, while Sir Chinubhai Madhav Lal has en- 
dowed the Institute of Science of Ahmedabad with 
six lakhs, giving a further two lakhs to the Gujerat 
College, with which it is associated. Lord Hardinge 
also dealt with the question of university buildings 
and libraries. The universities of India have recently 
made laudable efforts, which have been substantially 
aided by the Government, to provide for themselves 
local habitations in the shape of buildings befitting 
their dignity, and libraries where their alumni may 
learn the use of books and the methods of investiga- 
tion and research which collections of books alone 
make possible. Calcutta has not been behindhand. 
Thanks to the generosity of the Maharaja of Dar- 
bhanga, the University is now possessed of a handsome 
library. The students of the Law College are accom- 
modated in a hostel towards which the Government 
contributed three lakhs. The Government has also 
made a grant of eight lakhs for the purchase of a 
valuable site which abuts on the University buildings, 
and the acquisition of which should permit of further 
extension. 

SOCIETIES AND ACADEMIES. 
LonpDon, 
Physical Society, March 26.—Dr. A. Russell, vice- 
president, in the chair.—Prof. A. W. Porter and F. 
Simeon: The change of thermal conductivity with 
fusion. The change in question was determined for 
mercury and for sodium by finding the temperatures 
at different points of a cylinder of the metal contained 
in a glass tube. The ends of the cylinder were main- 
tained at such temperatures that the metal was liquid 
half-way down its length, the remaining part being 
solid. The temperatures were taken by means of 
thermo-electric junctions inserted in narrow tubular 
depressions which had been formed in the glass tube 
by forcing a knitting needle down into the locally 
heated glass. The ratio of the thermal conductivity 
for solid and liquid was estimated from the slope of 
tangents drawn to the temperature-curve on each side 
of the melting point. The values of these ratios are 
of the same order as the ratio of the corresponding 
values of the electrical conductivities. The mean 
value for mercury is 3°91, and for sodium 1-31.—Dr. 
J. A. Fleming: An instrument for the optical delinea- 
tion and projection of physical curves such as hystere- 
sis, resonance, and characteristic curves. This instru- 
ment is designed for projecting on to a screen or 
photographing on a plate such curves as magnetic 
hysteresis, resonance, or characteristic curves which 
can be performed slowly, or are non-periodic or non- 
repetitive.—Dr. P. Phillips and J. Rose Innes: The 
stability of some liquid films. The authors give a 
simple method of calculating the equilibrium form of 
a thin film which is a surface of revolution. They 
then consider the stability for certain kinds of dis- 
placement of three classes of such films, viz., the 
sphere, the cylinder and the catenoid. The mathe- 
matics used is quite elementary throughout and the 
NOL 237.2, VOL OS) 


treatment is rigorous.—Prof. A. W. Porter and E. 
Talbot Paris: A demonstration of the green-flash of 
the setting of an artificial sun. <A large disc of card 
mounted so that it can be slowly rotated has a hole, 
1 in. in diameter, cut in it about 2 in. from the peri- 
phery. This is covered with red gelatine films, and is 
illuminated from behind so as to form an artificial 
sun. The front of the disc is covered with white 
Bristol board and is moderately illuminated by a lamp 
in front. This sun is viewed through a rectangular 
aperture (4 in. wide) in a blackened board, the lower 
edge of the aperture serving as the horion. When the 
disc is rotated the artificial sun sets and green after- 
images are obtained of characters varying according 
to the amount that the eye has been exposed to the 
bright sun. If the sun is not viewed until immediately 
before the complete setting the after-image represents 
simply the disappearing segment to which it is due. 
The authors claim that this phenomenon is what is 
often described as the green-flash at sunset, though 
they are ready to admit that other (but probably rarer) 
phenomena also go under the same name. 
MANCHESTER. 
Literary and Philosophical Society, March 23.—Mr. F. 
| Nicholson, president, in the chair.—T. A. Coward: 
A note on the behaviour of a blackbird—a problem in 
mental development. The author referred to the 
habit of certain birds—individual, not specific—which 
when stirred by spring rivalry will fight with their 
own reflections as seen in windows, and spoke, in parti- 
cular, of a male blackbird which for more than a month 
has been daily assaulting its own image in a particular 
window. A blackbird, presumably the same, behaved 
in a similar way at the same window all through last 
spring. Attention was directed to the psychological 
problem presented by a bird with an excellent memory 
but without any apparent power of learning by ex- 
perience. ‘The recollection of this visionary antagonist 
was stimulated by the seasonal sexual activity and 
died down with the normal waning of this force.— 
A. W. Rymer Roberts: Two cases of parallelism in 
the Aphidz. Parallel series of aphids may co-exist 
| on the same or on different plants, having the same 
| ancestry but differing in habits and sometimes also 
in form. The phenomenon was first brought in pro- 
minence by Cholodkovsky’s recent researches on 
Chermes. Though there exists some doubt, in the 
light of more recent research, whether the instances 
principally relied upon are not those of distinct bio- 
logical species, other instances have been discovered 
of as many as four parallel forms being descended 
from the winter-form on the secondary host-plant in 
certain species of Chermes. Parallelism exists also in 
other groups, as in the Pemphiginze, two instances 
observed being (1) Thecabius affinis, a species migrat- 
ing between poplars and Ranunculus, and (2) 
Hamamelistes tullgreni, so far only found on birch. 
T. affinis has been found continuing to live over the 
winter on Ranunculus after the migrating individuals 
have returned to the poplar. H. tullgreni has been 
observed in England for the first time during the past 
year. Certain of its forms resemble scale insects. It 
has so far only been found upon birch, but winged 
individuals fly from that to some other plant, leaving 
wingless individuals to continue the race on the birch, 
both being descended from a single ancestress by 
parthenogenesis. 
EDINBURGH. 
Royal Society, March 1.—Prof. Hudson Beare, vice- 
president, in the chair.—H. Levy: The resistance of 
a fluid to a body moving through it. In this paper 
