1816.} during the Year 1815. 53 
John could not succeed in detecting any iodine in this fucus ; 
but his experiments were made upon a small quantity of the fucus, 
and he did not employ any very delicate test. 
Gaultier de Claubry found the_fucus serratus to contain albumen, 
a mucilaginous substance precipitated from water by alcohol, and of 
a dark colour; green colouring matter soluble in hot alcohol and 
precipitating as the liquid cools;* another vegetable matter, 
having little taste and soluble in water and alcohol; the same salts 
as the fucus saccharinus, but much more stibcarbonate of soda and 
more iodine than the fucus vesiculosus. 
The fucus siliquosus was found by him to contain the following 
substances. A great deal of vegeto-animal matter (albumen) ; 
a brownish-red mucus; a bitter substance soluble in alcohol; a 
matter soluble in hot alcohol and precipitating in greenish-brown 
flocks on evaporating the liquid ; the same salts as the fucus saccha- 
rinus, but very little iodine. 
The fucus filum contained a scarcely sensible quantity of vegeto- 
animal matter; a mucous substance; a small quantity of matter 
which precipitates in flocks* from the alcohol that had been digested 
on the plant; the same salts as the fucus saccharinus, but very little 
lodine. 
From the experiments of Gaultier de Claubry, it appears that 
the saccharine matter of the fuci possesses the characters of manna. 
X. ANIMAL BODIES. 
1, Vauquelin some time ago published an analysis of the brain of 
animals, from which he concluded that phosphorus was one of its 
constituents. This induced Professor John to undertake a set of 
experiments upon the brain, nerves, and spinal marrow of calves. 
(Schweigger’s Journal, vol. x. p. 155.) These experiments in- 
duced him to conclude that phosphorus is not a constituent of the 
brain ; but that it exists in that substance in the state of phosphate 
of ammonia. I must acknowledge, however, that his experiments 
do not appear to me quite conclusive. The subject is perhaps too 
delicate to be determined by chemical analysis in its present state. 
He employed always brain extracted from the animal imme- 
diately after death and still warm. 
The liquid portion of the brain assumed a liver colour when 
heated. It consisted of albumen, water, and traces of various 
salts. The solid matter of the brain produces no change in the 
colour of litmus paper, even when exposed to the air for days. 
John supposes that if it contained phosphorus, phosphoric acid 
would be formed by such exposure. When heated it gave out 
the odour of meat, but no fat separated. “When all the liquid 
portion was evaporated the matter became brown, and at last 
melted and was charred. ‘The silver vessel, in which the experi- 
ment was made, assumed a black colour, indicating the presence of 
* Probably wax.—T, 
