330 MAT ORE 
the Carrick Hills near Ayr, iurnishes one of his care- 
ful studies in petrography. J. W. Gregory, attracted 
towards geographical subjects, uses the Campsie Fells 
as a text for an essay upon cirques. Matthes’s ob- 
servations on ‘‘nivation,’”’ which leads to the sinking 
of a snow-patch into a hollow worked out by frost 
and thaw upon its margins, might well be added to 
those quoted in favour of the ‘meteoric theory” of 
the origin of cirques. The edges of certain plateaus 
in Spitsbergen, as Prof. Gregory knows better than 
most geologists, afford excellent evidence of the 
potency of ‘‘nivation.”” This paper will lead to the 
further consideration of one of the commorest and 
most puzzling surface-forms of our British highlands. 
A very elaborate gravimetric survey of Italy has 
been undertaken by Prof. V. Reina and Dr. G. 
Cassinis, the observations being ite e the 
Memorie della R. Accademia dei Lincet, vol. ix., p. 5. 
The apparatus used consisted in a sodtheateee of 
Sterneck’s pendulum, the apparatus being connected 
with a wall table with a bipendular support. The 
stations chosen were Rome, Leghorn, Arcetri, Genoa, 
Vienna, and Potsdam, the two latter serving as bases 
of comparison. The uncorrected values observed for 
g at these stations exceeded 980 by 0-367, 0-534, 0-491, 
0-557, 0-860, and 1-275 cm./sec.?, and the corrected 
values reduced to sea-level by the use of various 
formule are in every case, except one in excess of the 
values, calculated for the corresponding latitude from 
the Potsdam formula, the excesses being in every 
case less than o-1 cm./sec.’. 
THE present year marks the tenth anniversary of the 
Aerodynamic Institute of Koutchino, which was 
founded on the initiative of its director, Dr. D. P. 
Riabouchinsky, for the purpose of researches on fluid 
pressures and other problems connected with aerial 
navigation. The main laboratory is equipped with 
wind tunnels, whirling tables, apparatus for testing 
propellers, and, in short, all the necessary appliances 
for experimental work, while attached to the institute 
there is a hydrodynamic laboratory where use is made 
of a small river called the Pékhorka. The staff con- 
sists of Dr. Riabouchinsky, three assistants, six 
mechanics, and several workmen. ‘The _ published 
work alone includes investigations on propellers, rota- 
tion of plates and oscillation of pendulums in a cur- 
rent, and effects of the size of tubes on air currents 
passing through them, as well as papers of a more 
mathematical character. A descriptive pamphlet has 
been published in connection with the present occa- 
sion. It is printed by J. N. Kouchnereff, of Pimeno- 
skaia, but is probably obtainable from the director. 
It might, however, Fave been safer if Dr. Riabouchin- 
sky had left the question of locomotion through inter- 
planetary space to M. Jules Verne and Mr. H. G. 
Wells. 
THREE communications from the physical laboratory 
of the University of Leyden which have reached us 
are of exceptional interest. The first is a reprint of 
the address which Prof. Onnes delivered before the 
Swedish Academy on the receipt of the Nobel Prize for 
It describes the apparatus and the methods 
NO, -2320.eV0L. 03] 
IQT3. 
,May 28, 1914 
adopted for the production of extremely low tempera-_ 
tures at Leyden, and is well illustrated. The second 
is a report by Prof. Onnes to the third international 
congress on refrigeration held at Washington and 
Chicago last year. It deals with the work done in the 
professor’s laboratory since the last meeting of the 
congress in Vienna. The chief results relate to radio- 
activity, magnetic susceptibility and electrical resist- 
ance at temperatures down to 2° or 3° absolute. 
Radio-activity remains unchanged, the susceptibility 
of paramagnetic substances decreases below the Values 
given by Curie’s law of variation inversely as the 
absolute temperature, and in some cases reaches a 
maximum and decreases for temperatures lower still. 
The resistivities of metals decrease and almost dis- 
appear at temperatures 10° or 20° above the absolute 
zero. The third paper is a report to the same con- 
gress on low-temperature thermometry by Prof. 
Onnes. He advocates the substitution of the helium 
for the hydrogen thermometer as the standard scale 
for low temperatures. If the nitrogen thermometer 
has to be substituted for the hydrogen thermometer 
at high temperatures, he would suggest that the 
helium scale should extend up to 100° C., and the 
nitrogen scale begin at that point. As auxiliary 
thermometers for low temperatures he recommends 
platinum or gold resistance thermometers, but in both 
cases it is necessary to calibrate the resistance ther- 
mometer by comparison with a helium thermometer 
at a considerable number of points on account of the 
strong curvature of the resistance-temperature curve 
at very low temperatures. 
AS a supplementary note to the article on the 
“Total Eclipse of 1914 in Turkey and Persia,’ which 
appeared in last week’s NarurkE, attention should be 
directed to the Map of Armenia by the late H. F. B. 
Lynch, on the scale of 1: 1,000,000, published by Mr. 
Edward Stanford, Ltd. The map is in a very useful 
and portable form, and covers the whole country from 
Trebizond to Tabriz. It can be obtained apart from 
Mr. Lynch’s book. 
OUR ASTRONOMICAL COLUMN. 
ComET 1914b (ZLATINSKy).—A Kiel circular. dated 
May 20, and an appendix to Astronomische Nach- 
richten, No. 4736, give the following elements and 
ephemeris, calculated by Prof. H. Kobold, of Zlatin- 
sky’s comet (1g14b), based on observations on M: aS 
16, 17, and 18 :— 
Elements. 
T =:914 May 8°3618 Berlin M.T. 
wo =116° 17°85’ | 
8 = 32 43°22 7 
36 31 | 
log 9 =9'7 3478 
Ephemeris 12h, 
1914°0 
Berlin M.T. 
R.A. Dec. Mag. 
hs “mi 3s ? 
May 27 7 12 Az +31 30:6 58 
28 7 25 55 28 37-9 ; 
2!) 7 34 42 2549'S O-1 
30 748 8 23 7-4 6-2 
St < SE_32 ZOD) 
June 1. 8 I 18 7-6 
j Pree Ss: 7 
2 3913) 19 I5 51-1 : 
3 S 20,2 13 43°7 0-7 
4. S a2 Ones +1f 45:0 
