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The reading of a paper entitled, " On the action of certain Inor- ganic Compounds when introduced directly into the Blood." By James Blake, Esq., M.R.C.S. Communicated by P. M. Roget, M.D., Sec. R.S., was resumed and concluded.

The present paper is a continuation of a memoir read at the Aca- demic des Sciences of Paris, in 1839, and entitled, " Effets de di- verses substances salines, injectees dans le systeme circulatoire *.

After some preliminary remarks on the mode in which the ex- periments were conducted, and on the assistance derived from the jKBmadynamometer of Poiseuille (or instrument for measuring the pressure of the blood circulating in the vessels), the author gives a list of the various saline substances of which he noted the effects when they were severally injected either into the venous or the arterial systems, arranged according to the nature of those effects. He finds, in general, that all the salts having the same base exert similar actions when introduced directly into the blood. He carefully inquires into the phsenomena apparently arising from the direct contact of each of the substances above enumerated mth the animal tissues ; and more particularly into the effects produced on the heart, on the muscular and the nervous tissues, and on the pul- monary and systemic capillaries.

The first series of experiments related are those on the action of the salts of magnesia : these are found, when introduced in any quantities into the blood, to arrest altogether the action of the heart ; but a still more remarkable effect which results, is the complete pro- stration of muscular power. The salts of zinc have a similar opera- tion under the same circumstances, but produce the same effects in smaller quantities. The action of the salts of copper, of lime, of strontia, of baryta, and of lead, are considered successively in the order in which they are more closely related by their physiological actions. The author particularly notices the peculiar action which the saltS'of the three last-named substances exercise on the muscular tissues, occasioning contractions in them during many minutes after death produced by their introduction into the blood. These mus- cular movements were, in some cases, observed forty-five minutes after the cessation of the heart's action. Experiments with the salts of silver and of soda are then detailed substances, which exhibit a remarkable similarity in their actions on the pulmonary tissue, on the heart, and on the systemic capillaries : for while, in the case of all the other salts already mentioned, death seems to be produced by the destruction of the irritability of the heart, the fatal result with the salts of silver and of soda is the consequence of their action on the tissue of the lungs. The physiological actions of the salts of


 * Published in the "Archives Generales de Medecine ; Nov. 1839."