530 
Proceedings of the Royal Society 
( b ) Dr Germain See’s “ L’acide salicylique et le salicylates dans 
le traifcement de la gontte et des rliuinatismes,” Rapport a 
X academic de Medecine de Paris , June and July 1877. 
(c) Fontheim’s “ De Taction de Tacide salicylique employe comme 
medicament,” Moniteur Scientifique, 1875, p. 853. 
PRIVATE BUSINESS. 
Letters were read by the Secretary from Mr Dudgeon of Cargen, 
and from Mr Aitken, on the recent display of Iridescent Clouds. 
Mr A. J. G. Barclay was balloted for, and declared duly elected 
a Fellow of the Society. 
Monday , 18^ January 1886. 
Sheriff FOEBES IEVINE, Vice-President, 
in the Chair. 
The following Communications were read : — 
1. On the Eelation between the Densities and the Atomic 
Weights of the Elements. By Professor Crum Brown. 
2. Observations on Earth- Currents in Ben Nevis Observa- 
tory Telegraph Cable. By H. N. Dickson. (Plate XIX.). 
Telegraphic communication between Ben Nevis Observatory and 
Fort- William Post Office is kept up by means of a line which con- 
sists of an ordinary telegraph wire from Fort-William to Auchintee 
Farm at the base of the mountain, and a cable laid underground 
from thence to the summit. At Fort-William the wire is put to 
earth in the usual way, while at the Observatory the return wire is 
attached to the iron-wire sheath of the cable. Formerly the wire 
was worked by means of Wheatstone’s ABC instruments, but in 
April last these were replaced by single needle “ sounders.” With 
both instruments the presence of earth-currents has been frequently 
observed, occasionally of such strength as to interfere with the 
proper transmission of signals, and from the working of the needle 
