98 Proceedings of Boyal Soeiety of Edinhurgh. [sess. 
Analyses of this ptomaine gave the following results : — 
L 
Found. 
A 
II. 
III. 
Calculated for 
c.h^^no^. 
Carbon, . . 
. 39-91 
40-04 
— 
40-00 
Hydrogen, . 
. 8-20 
8-16 
— 
8-00 
Nitrogen, 
— 
— 
9-30 
9-33 
Oxygen, . . 
— 
— 
42-66 
The above figures correspond with the formula C 5 HJ 2 NO 4 . 
A ptomaine with exactly the same composition and properties 
was extracted from pure cultivations of Micrococcus scarlatinas in 
peptonized gelatine* by the following method : — 
The contents of twenty tubes were boiled with water, filtered, and 
the filtrate precipitated with subacetate of lead. This precipitate 
was filtered off, a current of sulphuretted hydrogen passed through 
the filtrate, and the plumbic sulphide separated by filtration. The 
filtrate was concentrated by evaporation, and then extracted with 
amylic alcohol. The amylic solution was repeatedly treated with 
water, then concentrated, acidulated with sulphuric acid and 
repeatedly shaken with ether, which removes the oxy-aromatic 
acids. Freed from ether it was evaporated to a quarter of its 
volume, and thus volatile fatty acids were driven off. The sulphuric 
acid was precipitated by baryta, and the precipitate removed by 
filtration.' The excess of baryta was precipitated by a current of 
carbon dioxide, and this was also removed by filtration. The fluid 
was heated for some time on a water-bath, cooled, and precipitated 
with mercuric chloride. The precipitate was washed and decom- 
posed by sulphuretted hydrogen ; the mercuric sulphide was filtered 
off, and the filtrate concentrated. The hydrochloride of the ptomaine 
was subsequently deposited in the crystalline condition. It was 
dissolved in water, and then treated with pure calcium hydroxide, 
which liberated the base. The ptomaine was separated by chloroform, 
in which it is soluble ; and it was finally purified by washing with 
alcohol and water. 
These subcultures were ten weeks old. 
