
ON THE PHYSIOLOGICAL ACTION OF MEDICINES. 115 
water-lines of a ship. The vessel No. I. was constructed on the waye-line ; 
the methods and rules for which he proceeded to explain by diagrams. 
Mr. Scott Russell expressed to the Section the regret which he felt in the 
loss of Sir John Robison, who had been a zealous member of this Committee. 
One of his last acts had been to express his interest in their labours. 
Report on the Physiological Action of Medicines. 
By J. Buaxe, .R.C.S. 
In regard to the following observations on the action of medicines I must 
beg to observe, that I have used the word medicine in its most general sense, 
and considered it as comprehending any, bas or force capable of exerting 
an influence on the animal economy. Under this point of view it is evident 
that the field of investigation is most extensive. The part of it to which I 
have more particularly directed my attention has been, the phenomena pro- 
duced by the introduction of yarious substances directly into the blood. 
Although such an inquiry does not promise to lead to any direct practical 
results, it nevertheless offers to us the means of producing certain definite 
changes in the circulating fluid and in the tissues, in a much readier manner 
than we can hope to de hy any other method; and there can be little doubt 
that a careful analysis of the facts thus obtained, will afford data which 
must sooner or later prove available for the adyancement of medical science. 
In the last memoir which I published on this subject, I alluded to a fact 
which seemed indicated rather than proved by the experiments I had then 
made; this was, the apparently analogous action of isomorphous substances 
when introduced directly into the blood, But experiments which would bring 
into one class, as regards their physiological action, substances so dissimilar 
in their therapeutical properties as comman salt and nitrate of silver, mag- 
nesia and iron, evidently required to be carefully repeated and extended, before 
they could admit of being received as data for founding so extraordinary a 
generalization: at the same time the importance of such a law, if discovered, 
affording, as it would do, the first step to a more scientific insight into the 
action of substances on the animal economy, appeared to me so evident, that 
I considered I could not better carry out the objects proposed to me by the 
Association, than hy extending my researches in this direction, so as to yerify 
or disprove the law in question, — 
I haye also instituted a series of experiments to ascertain if in animals, 
with whose food foreign substances were mixed, these substances would com- 
bine with or be deposited in the tissues; and if so, whether they would be 
found in greater quantity in one tissue or organ than in another. For this 
purpose I have fed rabbits on food with which salts of strontian in one in- 
stance, and in another salts of lead, were mixed; conceiving that the stron- 
tian might possibly replace the lime in the bones, and that the lead would 
readily furnish me with facts, from the facility with which it can be detected, 
and from its uniting easily with the animal tissues, at least according to the 
generally-received opinion, The first series of experiments, or those with the 
salts of strontian, have led to only negative results, owing to the difficulty of 
separating strontian from lime, In my experiments with the salts of lead, I 
have arrived at conclusions which are opposed to the opinions generally en- 
tertained on the absorption and deposition of this substance : I therefore think 
it necessary to relate the experiments in detail. 
I procured two full-grown healthy rabbits, and mixed six grains of ace- 
tate of lead with their food daily, so that each was taking three grains a-day ; 
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