320 
Proceedings of the Royal Society 
It appeared to the author that facts having an important bearing 
on the question, which of these is the better representation of the 
constitution of such bodies, might be obtained by the study of the 
sulphur compounds of trimethyl-sulphine, of the corresponding 
selenium compounds, and of the intermediate substances. 
The following list, in which each substance is formulated — a, 
on the assumption of tetrad sulphur and selenium, and b , on the 
supposition of molecular union illustrates this idea. 
h. 
(CH 3 ) 2 S, ch 3 hs. 
(CH 3 ) 2 S, (CH 3 ) 2 S , (CHJ 2 S. 
(CH 3 ) 2 Se , CH,HS . 
(CH 3 ) 2 Se', (CH 3 ) 2 Se, (CH 3 ) 2 S. 
(CH 3 ) 2 S, CH 3 HSe. 
(CH 3 ) 2 S , (CH 3 ) 2 S , (CH 3 ) 2 Se . 
(CH 3 ) 2 Se , CH 3 HSe . 
(CH 3 ) 2 Se , (CH 3 ) 2 Se , (CH 3 ) 2 Se . 
(CH 3 )_S , (CH 3 ) 2 Se , (CH 3 ) 2 Se . 
(3) and (6), (5) and (7), and (4) and 
(10) form three pairs of isomers. 
Upon any theory (3) and (6) may be expected to be different, but 
it is not so with the other two pairs. They ought to be different, 
if the assumption of tetrad sulphur and selenium is correct, but 
on the theory of molecular combination it is difficult to see how a 
difference of properties could be accounted for. 
The hydrate and also the carbonate of trimethyl-sulphine are 
readily acted upon in the dry condition by sulphuretted hydrogen, 
and the product is colourless if air has been rigidly excluded. The 
characteristic reaction with nitroprusside shows the product to be 
a sulphide or sulphhydrate, but the action of oxygen upon it is so 
rapid that it has not yet been obtained in a condition fit for 
analysis. Before attempting to prepare it in a state of purity, it 
was thought best to examine the products of its oxidation. These 
are — (1), an orange polysulphide, which in the presence of moisture 
(CH„) 2 S , (CH 3 ) 2 Se , (CH 3 ) 2 S . 
(1.) (CH 3 ) 3 S— SH 
(2.) ((CH 3 ) 3 S) 2 S 
(3.) (CH 3 ) 3 Se — SH 
(*■) ((CH 3 ) 3 Se) 2 S 
(5 ) S 
W (CH 3 XSe b 
(6.) (CH 3 ) 3 S— SeH 
(7.) ((CH 3 ) 3 S) 2 Se 
(8.) (CH 3 ) d Se — SeH 
(9.) ((CH 3 ) 3 Se) 2 Se 
(CH 3 ) 3 Se 
Of these it is obvious that 
