TRANSACTIONS OF THE SECTIONS. 41 
of view, from the constituents of the blood, are those which give rise to the most 
marked phenomena. Two drachms of arsenic acid injected into the veins will pro- 
duce no marked effect on any organ; but a grain of chloride of palladium, or two 
grains of nitrate of baryta, are sufficient instantly to arrest the movements of the 
heart. Several other instances analogous to those quoted were pointed out. 
On the Action of Oxalic Acid upon the Dead Tissues of the Animal Body. 
By H. Letuesy, WB. 
It has been stated by Dr. Coindet, Dr. Christison and others, that oxalic acid does 
not appear to have any corrosive action on the stomach like the mineral acids. Dr. 
Letheby however remarks that these statements are opposed to the observations 
which he has made. In every case which he had examined of poisoning by oxalic 
acid, the stomach soon after death was found to be completely corroded, so that it 
would scarcely hold together. Numerous experiments were made with various 
animal tissues, such as submitting skin, stomach, intestine, muscle and tendon to 
the action of solutions of oxalic acid of different strengths. After standing about 
twelve or fourteen hours at a temperature of 60° Fahr., it was found that the cel- 
lular and mucous tissues of each underwent either complete solution, or else were so 
softened that they broke down under the pressure of the thumb and fingers; the 
albuminous and muscular tissues were also softened and looked as if they had been 
scalded. 
On an important Chemical Law in the Nutrition of Animals. 
By R. D. Tuomson, M.D. 
This paper was a recapitulation of the results obtained by Dr. Thomson when 
engaged on the Government Commission, and published in the Report presented to 
Parliament, and also in Dr. Thomson’s ‘ Researches on the Food of Animals.’ 
On the Difference in the Physiological Actions of the Yellow and Red Prus- 
siates as an evidence of their containing dissimilar Radicals. By H. 
Letuesy, MB. 
In the course of his inquiries into the actions of the various compounds containing 
cyanogen on the animal ceconomy, the author was particularly struck with the great 
dissimilarity in the effects produced by the yellow and red prussiates of potash, and 
was led to think it might furnish some evidence upon the side of Liebig’s doctrine, 
that the two salts contain radicals which are dissimilar. To prepare himself for this 
inquiry, however, he thought it necessary to ascertain what would be the effects of 
the simple and the double cyanides, and then to experiment with the yellow and red 
prussiates of similar bases. Of the simple cyanides, he chose those of potassium, 
sodium, ammonium, mercury, lead, iron, zinc and silver ; and, to provide against any 
fallacy which might arise from the action of the gastric juice, injected them into the 
veins or peritoneal cavity. Contrary rather to his expectations, it was found that 
_ they were all poisonous ; the soluble ones generally acting as quickly as prussic acid, 
_ while the others required a little longer time for the development of the symptoms ; 
but in all cases death followed their administration, from two to five grains being 
sufficient to produce such a result. Of the double cyanides, he chose those of po- 
 tassium and zinc, potassium and silver, potassium and nickel, and a mixture of 
cyanide of potassium with cyanide of iron. These also were found to be most poi- 
_ sonous, proving fatal in doses almost as small as the preceding. Now, these in- 
quiries clearly established two facts,—that neither the simple nor double cyanides 
_ could be given even in five-grain doses with impunity. The author was therefore 
_ much astonished to find that a class of salts regarded by some chemists as double 
_cyanides should have little or no action upon the animal ceconomy, and that they 
might be administered in doses of half an ounce without their exhibiting any un- 
pleasant symptoms whatever. This was found to be the case with the ferrocyanides, 
experiments having been made with those of potassium, sodium, ammonium, barium, 
lead, iron and silver. 
