598 DR E. A. LETTS ON THE 
standing. That which remained, when tested with baryta water, was found to : 
contain considerable quantities of carbonic anhydride. 
After the heating of the thetine salt had continued for a sufficient length of 
time—.¢., until it ceased to froth, the experiment was stopped, and the dark- 
brown viscous residue allowed to remain a night, but it did not solidify. It 
was then treated with water (in which it readily dissolved for the greater part) 
and the mixture distilled. A few oily drops passed over, which were not 
sufficient in quantity for examination, but were probably sulphate of methyl. 
The residue was still further diluted, and mixed with baryta water. An 
abundant white precipitate of sulphate of barium occurred. 
The solution filtered from this was evaporated over a water-bath and left a 
syrupy liquid which did not crystallise on cooling, nor did it yield a fixed residue 
when calcined, showing that no barium salts had been formed. It gave an 
abundant yellow precipitate with chloride of platinum, which dissolved in 
boiling water, and as the solution cooled orange-red crystals separated. These 
on analysis were found to consist of chloro-platinate of trimethyl-sulphine— 
2(CH,),SCl, PtCl,— 
1b Il. Ill. Theory. 
Platinum, . 5 : 344 34:49 34:22 34:9 
Carbon, : ‘ : 12°82 12°68 12°99 Lay 
Hydrogen, . ' : eh 3°46 3°46 3°2 
The volatile products of the reaction did not solidify on remaining at rest, 
and appeared to consist wholly of sulphide of methyl. 
Not a trace of thiodiglycollic acid was present in the non-volatile products, 
a fact which was proved by the absence of a solid residue when these products 
were neutralised with baryta and calcined. 
It is quite obvious that the sulphate of dimethyl-thetine suffers, when heated, 
a totally different decomposition from the hydrobromate. 
The substances produced from the former body indicate that its decomposi- 
tion when heated is expressed by the following equation— 
(CH). (CH;) 
Il 
I 
fon,  / So 
SO, = 0) + 200). 
\S—CH,— COOH \s—on, 
I 
(CH;) (CH;). 
the sulphide of methyl which escaped being no doubt due to the dis- 
sociation of the sulphine sulphate. 
Action of Heat on Hydrate of Dimethyl-Thetine—Having found that the 

