£ 3 85 3 
XXII. Hints on the Subject of animal Secretions. By Everard 
Home, Esq. F. R. S. Communicated by the Society for the 
Improvement of Animal Chemistry . 
Read June 22, 18 op. 
The brilliant discoveries of Mr. Davy on the powers of elec- 
tricity in producing chemical changes, suggested to me the 
Dr. Wollaston’s observations inserted in the Philosophical Magazine, were pub- 
lished after this paper had been laid before the Society. 
I was led to the present investigation, while preparing my lectures on the Hun- 
terian Museum, in which the secretions in different animals are to be considered. 
In September last, I engaged Mr. William Brande to assist me in prosecuting 
the inquiry. In November, I communicated my opinions to Sir Joseph Banks, and 
stated that I should bring them forward in my lectures ; at that time Dr. Young’s 
Syllabus was not published, and Dr. Wollaston’s opinions were unknown to me. 
Dr. Berzelius, Professor of Chemistry at Stockholm, published a work on Animal 
Chemistry, in the year 1806, in the Swedish language, in which he states, in several 
places, that he believes the secretions in animals to depend upon the nerves, although 
he is unable to explain how the effect is produced. In proof of his opinion, the 
following experiment is adduced: 
Trace all the nerves leading to any secretory organ in a living animal, and divide 
“ them, being careful to injure the blood-vessels and the structure of the organ 
(t itself, as little as may be: notwithstanding the continued circulation of the blood, 
“ the organ will as little secrete its usual fluid, as an eye deprived of its nerve can 
“ see, or a muscle whose nerve has been'divided can move. We may therefore easily 
“ conceive, that any trifling alteration in the nerves of a gland, may materially affect 
“ its secretion> the supply of blood being in every way perfect.” 
He says, the agency of the nerves in secretion has generally been disregarded, be- 
cause our attention is only called to their secret mode of acting, when we discover the 
insufficiency of all other explanation. Dr. Berzelius’s work was shown to me by 
Mr. Davy while this paper was in the press. 
