May 16, 1912] 
NATURE 
285 
allotted for the development of accommodation in 
Dacca and the buildings required for the new univer- 
sity in that place. Lord Hardinge hopes that the 
liberality of the Governntent will be supplemented 
by private liberality, and that before many years have 
passed efficient teaching universities will take the 
place of the examining and federal universities which 
India has to-day. 
Tue attendance at German universities forms the 
subject of an article by Mr. R. Tombo, jun., in the 
issue of Science for April 26. Mr. Tombo analyses 
the statistics given in the Deutscher Universitats- 
Kalendar for the summer semester of the present year. 
There are 57,398 students in German universities, as 
contrasted with 57,200 for the preceding summer 
semester. This is, however, exclusive of 5563 auditors, 
who, if added, would run the grand total to 62,961, 
as against 61,274 during the summer semester. The 
University of Berlin continues to lead the list with 
an enrelment of 9829 matriculated students. The 
University of Berlin is followed by the University of 
Munich, with an enrolment of 6797 matriculated 
students and 782 auditors. The University of Leipzig 
ranks third with 5170 matriculated students and 925 
auditors. Of the remaining universities, Bonn, Bres- 
lau, and Halle each have more than 3000 students; 
Géttingen, Freiburg, Heidelberg, Miinster, Strass- 
burg, and Marburg each have more than 2000, and all 
the other universities, except Rostock with 955, have 
each more than tooo students. Of the total number 
of students in German universities, 52,435 are from 
Germany, and of the remainder 160 only are from 
the British Isles. 
SOCIETIES AND ACADEMIES. 
Lonpon. 
Royal Society, May o.—Sir Archibald Geikie, 
K.C.B., president, in the chair.—A. Vernon Harcourt ; 
The variation with temperature of the rate of a 
chemical change. In an inquiry into the connection 
between the conditions of a chemical change and its 
amount, one of the conditions varied was that of the 
temperature of the solution in which the change took 
place (Phil. Trans., vol. clxxxvi., 1895, A, pp. 817-95). 
A relation was found to exist between this condition 
and the rate of change, expressed by the equation 
a; /A5, = ay Baye 
where «@ is the rate of change, or the number of 
minutes in which a definite portion of chemical change 
is accomplished, T, the absolute temperature 273°, 
and T any other absolute temperature. Not only do 
the numbers found from this equation agree very 
closely with the observed numbers, but the equation 
expresses a natural law which is nearly related to that 
upon which all calculations of gaseous volumes have 
long been based. Several later measurements of the 
rate of change at different temperatures have been 
published and compared with numbers calculated from 
other formulz. In an appendix to the present paper 
it is shown, by one of the authors of the previous 
paper, that the numbers thus calculated are in less 
close agreement with the actual measurements than 
numbers calculated from his formula given above, 
while also the formule have no physical interpreta- 
tion.—Dr. C. Chree: Some phenomena of sun-spots 
and of terrestrial magnetism at Kew Observatory. 
An investigation made some years ago by the author 
indicated the probability that a relation existed 
between the amplitude of the daily range of the mag- 
netic elements and the sun-spot area, not on the same 
day, but several days previously. The object of the 
present research was to inquire into the reality of 
NO. 2220, VOL. 89] 
this connection. It was found that there is a well- 
marked period of about 27-3 days in magnetic pheno- 
mena, in this sense, that if a certain day exhibits 
magnetic disturbance attaining the international 
standard ‘“‘2,’”’ as interpreted at Kew, a day which 
follows either 27 or 28 days after has nearly double 
the chance of attaining standard ‘‘2"’ that the 
ordinary day has. This 27-28-day period was not so 
clearly shown in the years of maximum sun-spot fre- 
quency of the epoch considered as in the years of 
minimum frequency, and was most clearly shown in 
certain intermediate years characterised by the 
number rather than by the magnitude of magnetic 
disturbances. The conclusion that a period of about 
27:3 days exists in ‘‘magnetic storms” had been 
reached some years ago by Mr. Arthur Harvey and 
Mr. E. W. Maunder, independently, considering re+ 
spectively data from Toronto and Greenwich, but their 
conclusions have not been universally accepted. The 
present investigation shows that the phenomenon is 
not confined to the large disturbances usually termed 
“magnetic storms,” but is exhibited in the daily range 
of the average day.—Sir Walter Noel Hartley and 
H. W. Moss: The ultimate lines and the quantities 
_ of the elements producing those lines in spectra of the 
oxyhydrogen flame and spark. In a recent paper by 
one of the authors (Proc. Roy. Soc., 1911, vol. Ixxxv., 
p- 271, Hartley) on some mineral constituents of a 
dusty atmosphere as determined both by flame and 
spark spectra, a brief reference was made to the 
method employed for ascertaining the weights of 
matter necessary to give calcium and copper lines in 
the spark. This work has been extended to about 
twenty elements. The quantities of the elements 
which render the ultimate lines in the oxyhydrogen 
| flame spectra had previously been carefully deter- 
mined. With the alkali metals it is found to vary 
between o:0008 milligram in the case of potassium, 
oor mgrm. rubidium and cesium, and ort mgrm. 
lithium. In the alkaline earth group, oor mgrm. 
strontium, o-I mgrm. calcium, and barium I-o mgrm. 
Silver 0-1 mgrm., copper 1:00 mgrm., and gold 
50 mgrms. Gallium, iridium, and thallium | oor 
mgrm., manganese o-oot mgrm., lead o-1, and tin 
Ioo mgrms. The gold spectrum shows the heads of 
very strong bands which correspond with lines in the 
spark spectrum. Tin shows no lines, but the edges 
| of bands or flutings which are enfeebled until scarcely 
| visible-—E. Marsden and C. G. Darwin: 
| formations of the active deposit of thorium. 
The trans- 
The 
present paper is concerned with a series of experi- 
| ments undertaken with the view of discovering the 
genetic arrangement of the various products in the 
active deposit of thorium, and more particularly the 
transformations occurring in the product or products 
included in thorium C. The results give strong 
' reason for supposing that, of the atoms of thorium C, 
35 per cent. emit @ particles of range 48 cm., and 
become converted into atoms of thorium D, while the 
remaining 65 per cent. emit 8 particles and dis- 
integrate into atoms of a very short-lived a-ray pro- 
duct, thorium C. The experiments also show that 
although the 6 rays of thorium C are extremely pene- 
trating (“=13-5 cm.-1 Al), yet they are practically 
unaccompanied by y rays, while the relatively soft 
B rays of thorium D are accompanied by a very intense 
penetrating y radiation containing more than six 
times the amount of energy of the 8 rays.—W. 
Wilson: The 8 particles reflected by sheets of matter 
of different thicknesses. (1) The radiation reflected 
when the 8 particles from uranium (loc. cit.) strike a 
screen can be split up into two parts, one with a 
very large coefficient of absorption, and the other with 
absorption coefficient of the same order as that of the 
