PROCEEDINGS 
OF THE 
ROYAL SOCIETY OF EDINBURGH 
vol. ix. 1876-77. No. 98. 
Ninety-Fourth Session. 
Monday , 19 th February 1877. 
DAVID STEVENSON, Esq., Vice-President, in the 
Chair. 
The Chairman reported that the Council had awarded the 
Makdougall-Brisbane Prize for the biennial period 1874-76, 
to Alexander Buchan, M.A., for his paper “ On the Diurnal 
Oscillation of the Barometer,” which forms one of an 
important series of Contributions by Mr Buchan to the 
Advancement of Meteorological Science. 
The following Communications were read : — 
1. On the Action of Sulphuretted Hydrogen on the Hydrate 
and on the Carbonate of Trimethyl-sulphine. By Professor 
Crum Brown. 
(. Abstract .) 
The investigation, of which this paper contains the first part, was 
undertaken with the view of throwing light on the constitution of 
salts of trimethl-sulphine. 
These salts have been represented in two different ways — 1st, 
as compound of tetratomic sulphur, and 2d, as molecular combi- 
nations of sulphide of methyl with methylic ethers, just as the 
ammonia salts have been represented as compounds of pentad nitro- 
gen, or as molecular combinations of ammonia with hydric salts. 
2 u 
VOL. IX. 
