219 
of Edinburgh, Session 1873-74. 
If, however, this analogy were perfect, we would anticipate that the 
action of oxygen, partially ozonised, would not have produced 
death, as the amount of ozone in these experiments certainly did 
not exceed 10 per cent. As it was, all we have observed is that the 
animal only lives a somewhat longer time in ozonised oxygen than 
in ozonised air. We are thus induced to regard ozone as having 
some specific action on the blood, or in the reflex nervous arrange- 
ments of respiration, that future experiments may elucidate. 
4. On a Compound formed by the addition of Bromacetic 
Acid to Sulphide of Methyl, and on some of its Deriva- 
tives. By Professor Crum Brown and Dr E. A. Letts. 
(. Abstract .) 
The sulphine compounds discovered by v. Oefele, indicate that, 
notwithstanding the difference of atomicity, there exists an analogy 
between sulphur and nitrogen, these compounds corresponding to 
the salts of the ammonium bases, not only in chemical properties 
but also in physiological action.* 
The research, the results of which are communicated in this 
paper, was undertaken with the view of examining this analogy 
in some other directions. 
It seemed reasonable to suppose that, as the nitrile bases, such as 
trimethylamine and strychnia unite with chloracetic acid to form 
compounds such as hydrochlorate of betaine and of glycolyl- 
strychnia, the sulphides of the alcohol radicals should act in a 
similar way. Experiments show that this is the case — bromacetic 
acid acting readily on sulphide of methyl to form a beautifully 
crystallised compound to which the authors give the name of 
hydrobromate of methyl-thetine. Analyses proved this substance 
to have the composition corresponding to the formula C 4 H 9 SBr0 2 
which is that of the sulphur analogue of the hydrobromate of 
betaine. 
(CH 3 ) 2 (CH 3 ) 3 
II III 
Br - S — CH 2 - COOH ; Br- N -CH a - COOH 
hydrobromate of methylthetine. hydrobromate of betaine. 
This view of its constitution is confirmed by its reactions. 
* Brown and Fraser, “ Proc. Royal Soc. Edin.,” March 4th, 1872. 
