ae J Ee ‘ ve re oe 
Phe / 4 . , 
y 
Fesruary 8, 1917]| aes 
of*ice. “This shows that a year such as 1915 might. 
hinder economic development in the west, but would 
most certainly favour it in the east. In the summer 
of 1916 these abnormal conditions to some extent 
were repeated, and fice was troublesome on the west 
coast until early in September. It should, however, be 
inted out that, despite this, the coal-mines in Advent 
ay exported 30,000 tons of coal in 1916. M. Hoel 
also directs attention to the advance of the glaciers in 
North-East Land since 1898. 
In a valuable paper which appears in ‘the January 
number of the Journal of the Franklin Institute, Mr. 
Ralph Brown, of Cornell University, summarises the 
results which have been obtained during recent experi- 
ments on the magnetic properties of iron and 
nickel under rapidly alternating magnetic fields. 
The belief that, at the frequencies in common 
use in power transmission, the permeability of 
iron was much less than in steady fields now 
appears to be unjustified, the apparent diminu- 
tion being due to the alternating fields never 
penetrating beneath a thin superficial layer of the iron. 
When, as in recent observations, this skin effect is 
allowed for, the permeability is found to retain its 
steady field value up to a frequency of a thousand per 
second. At a frequency of 10° it is, however, reduced 
to 500, at 10’ to 200, at 10° to 50, at 10° to 20, while 
at the frequency of light it is reduced to unity. The 
behaviour of nickel is like that of iron, except that its 
initial permeability is only too. 
Many readers of Nature will doubtless be interested 
to learn that the advertisement which appears in 
another column of a modern Elizabethan house which 
is to be let or sold refers to The Camp, Sunningdale, 
where Sir Joseph Hooker lived for upwards of a 
quarter of a century. 
Messrs. WITHERBY AND Co. have been appointed 
European agents for the ‘Journal of the Natural 
History Society of Siam.”’ 
OUR ASTRONOMICAL COLUMN. 
Tue Lake OKecHoBEE MetEoriTE.—A stony meteor- 
ite which has received this title at the U.S. National 
Museum has been described by G. P. Merrill (Proc. 
U.S. Nat. Mus., vol. li., p. 525). It is of rather special 
interest from the unusual circumstances attending its 
discovery, having been brought up in a fishing-net 
some three-quarters of a mile from the shore of the 
lake from which it receives its name. There is no 
definite record of a fall in this neighbourhood, but the 
finder recails a brilliant meteor which passed to the 
west of Ritta about thirteen years ago, and was accom- 
panied by explosive sounds. The fragments secured 
weigh about 1100 grams, and appear to have come 
from a mass originally ten or twelve inches in diameter. 
Notwithstanding its long immersion, the stone is still 
firm and shows the characteristic thin lustreless black 
crust. The chondritic type of the stone is at once 
evident in thin sections under the microscope. 
CiusTER VarrasLes.—In the course of an investiga- 
tion of variable stars in the cluster Ms, Prof. S. I. 
Bailey has found eight stars which have light-curves 
showing peculiarities not hitherto recognised (Har- 
vard Circular, 193). While the mean period of sixty- 
one variables of the ordinary cluster type in Ms is 
0-547 day, that of the eight stars in question is 
0:271 day, or about half. the more usual period. Prof. 
Bailey suggests that such a star may be formed of two 
variables, each being of the ordinary cluster type, and ' 
having the usual period of about half a day, with 
NO. 2467, VOL. 98] 
NATURE 
455. 
alternating maxima. This hypothesis is supported by 
‘peculiarities in the form of the light-curves, which can 
be resolved into two curves of the usual type.. Spectro- . 
scopic observations might provide further tests of this 
supposition. Prof. Bailey is of opinion that the 
uniformity of period of cluster variables must have 
some physical cause. which may separate them from 
other variables of short period. The mean period in 
w Centauri is 0-549d.; in M3, o-541d.; in Ms, 0:547d.; 
and similar results have been found for other clusters. 
It is still an open question whether these stars are 
spectroscopic binaries; if an ordinary cluster variable 
is a binary, a double variable, on the above hypothesis, 
must be a system of four components. 
Unitrep States Navat Osservatory.—The annual 
report of the superintendent of the U.S. Naval 
Observatory for the year ending June 30, 1916, 
fis notable for the attention directed to the 
increasing demands on the observatory in  con- 
nection with the submarine and aircraft services. 
New and improved methods and instruments for accu- 
rate and rapid navigational and plotting work have 
been devised, and instruction given to the personnel 
of the services. The policy of encouraging sugges- 
tions, and of making the necessary trials, is stated to 
have produced several new methods and instruments 
of value. 
The regular programme of astronomical observations 
was continued without intermission throughout the 
year, and included numerous observations of the satel- 
lites of Saturn and Uranus. It is interesting to note 
that the American ephemeris for 1919, which is in the 
press, will include tables for computing the rising and 
setting of the sun and moon. A special publication 
referring to the total eclipse of the sun of June 8, 
1918, visible in the United States, is in course of pre- 
paration. 
INTERNATIONAL AND NATURAL LAW.1 
HE idea of issuing photographic reproductions of 
the text of such works as can be said to have 
contributed either to the origin or to the growth of 
international law, together with English versions by 
competent scholars, and with introductions giving bio- 
graphical details and pointing out the importance of 
the text and its place in the development of the science, 
is a most worthy conception, and the commencement 
of its execution is a timely reassurance to the fears 
of those who imagined that the Germans had made 
an end of international law. The photographed text 
obviates possible mistakes in reprint. At the same 
time provision is made for the rectification of original 
misprints : where earlier authors have been ill-served 
by their printers a revised text will accompany the 
photographed text. The full bibliographies will be 
appreciated, and the portraits of the authors are in- 
teresting. The volumes form handsome quartos, and 
the typography might almost satisfy the exacting re- 
quirements of an Aldo Manuzio, 
(1) The introduction to Vattel, by Prof. Albert de 
Lapradelle, sketches the life of the author, examines 
the character of his work and the grounds of its suc- 
cess, and assesses its value. A sustained discussion of 
Vattel’s position was very desirable, and Prof, de 
Lapradelle has successfully met the need; the only 
weakness of his monograph is occasional repetition, 
a fault of form inevitably arising from his division of 
1 “The Classi i ” Edi S 
President = the A sean Intenso ae The Drek 
des Gens.” By E. Vattel. Text (2 vols,), and Translation by C. G. Fenwick 
(r-vol.). (2) *‘De lure Nature et Gentium Dissertationes.” By Samuel 
Rachel, edited by Ludwig von Bar (r vol.) ; with Translation by J. Pawley 
Bate (x vol.). (Carnegie Institution of Washington, Ie) eee 
