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take of this inflammation, and a number more or less considerable of black spots resembling sloughs, or longitudinal zones of a deep red colour, are discovered) which depend on the extravasation of black blood between the coats, or in the chorion of the mucous membrane. Sometimes small ulcers are found near the pylorus; but most frequently the inflammation confines itself to the fauces, stomachy and great intestines, which phenomenon appears to arise from this cause, that the poison has been longer in contact with these parts than with the others. It is easy to perceive, that the lesions we have just described have the greatest analogy to those produced by the corrosive poisons. In fact, we do not hesitate to declare, that there exists a perfect identity between the alterations of the digestive canal produced by the poisons of these two classes When introduced into the stomach.
2ndi The lungs exhibit very Gommonly lesions more or less considerable; their colour is sometimes violet; but in general it is a deeper red than in the natural state. Their texture is more tight, dense, distended with blood, and less crepitating, at least borne parts of them: it is not uncommon to find in them a bloody Serosity. These phenomena may arise from the repeated and fruitless efforts to vomit; we are of opinion however, that they are frequently the result of a special action of the poisonous substance upon the lungs: the hellebore seems to us to be principally in point.
3rd. The Ventricles and auricles of the heart, are more or less distended by blood differently coloured, according to the period at Which the dissection takes place. In a number of circumstances, this fluid is found coagulated one or two hours after death, and it is almost constantly in this state at the end of fifteen or eighteen hours. This pathological fact, of which we warrant the correctness, is far from confirming the opinion advanced by some authors, that in poisoning by vegetable substances the blood remains fluid for a long time* In truth, they have principally wished to fepeak of narcotic substances; but we shall see, when giving the history of these poisons, that their assertion is totally void of foundation.
<4th- The brain and its meninges exhibit no notable lesion in cases of poisoning by acrid substances ;- nevertheless, a fulness of the veins running over the external surface of this viscus, is sometimes observed.
5th. The other organs have not appeared to us to undergo any sensible alteration from poisonous substances of this class.
When applied to the surface -of the skin, or the cellular textare, these poisons produce the local phenomena which we have described; and when death takes place, the lesions we have enumerated, are found, excepting that the digestive canal is seldom affected. .
It results from the foregoing considerations: 1st, that, in a case of poisoning, the juridical physician will be often greatly embarrassed to determine, from the simple lesions of the internal organs, whether the poison ingested belong to the class of acrid, or to that of corrosive poisons; 2nd, that in the case where chemical analysis shall have proved that the poisoning has not been produced by one of the corrosive poisons, and that every thing favours the belief of its belonging to the class of acrid poisons, it will be impossible to decide, by the simple examination of lesions on dissection, what is the poison that has produced them, these lesions being pretty nearly the same in all; 3rd, in fine, that, taking into consideration the symptoms, and especially the intense inflammations produced by acrid substances, we cannot confound the poisoning produced by them, with that which results from the narcotic, or even from the narcotico-acrid, poisons, which either do not inflame the texture of the organs, or produce only a very slight inflammation.
GENERAL ACTION OF ACRID SUBSTANCES ON THE ANIMAL ECONOMY.
It seems natural to pass to general considerations on the mode of action of the poisons contained in each class, after having given their particular histories in distinct sections, and described the lesions and general symptoms to which they give rise. It is evident that no inconvenience can follow this method, when the indi-> viduals which compose the class unite together a very great number of common characters, and their physiological action is almost identical. Generalities are then even indispensable, on account of the facility they afford of retaining a multitude of important facts. But is this the case with the class we are treating of ?— We are of opinion that it is not. How many substances do we see classed together, which evidently exercise a different mode of action. What connexion is there, for instance, between the Hellebore, the Spurge-flax, and the Jatropha Curcas ?—Do not these two latter substances act by producing a strong inflammation, whilst the first, being rapidly absorbed, exerts a fatal action on the nervous system, and produces only a slight inflammation? If we have united in one catalogue objects so dissimilar, it is because they are found in the- classification proposed by Vicat, adopted by Fodere, and which we have followed. We are conscious of the extreme difficulty attending a new arrangement founded on the mode of action of poisons; and, till we shall have multiplied the experiments in the different climates of Europe, we shall not hazard the proposal of an Essay at classification. These considerations will exonerate us from giving to this article all the extent ic is capable of receiving; we shall confine ourselves to the propositions following:
1st. The major part of acrid poisons produce a strong local irritation followed by inflammation, more or less intense, of the parts to which it has been applied, and death takes place through the sympathetic irritation of the nervous system, without the poison being absorbed: the animals almost constantly die in a state of dejection, and of general insenstbility. In these cases, the phenomena of poisoning make their appearance more rapidly when the poison has been introduced into the stomach, than when it has been applied to the cellular texture. The Spurge-flax, Jatropha Curcas, &c. appear to act in this manner. . .
2nd. Sometimes, after having inflamed the texture, the poisonous substance is slovvly absorbed, and carried into the circulation; and its effects depend on the direct action it exerts'on the nervous system, and on the sympathetic irritation of this same system. Under certain circumstances, the poisons thus absorbed act on the rectum ; such are the colocynth and savine. Some affect the lungs also.
3rd. There exists a certain number of acrid poisons, which are rapidly absorbed, and carried into the circulation, and which produce in a short time repeated vomitings, vertigoes, and the most perfect stupefaction. The roots of black and white hellebore are of this number. Death takes place more speedily when these poisons are applied to the cellular texture, than when they are introduced into the stomach. Does this phenomenon depend on the digestion of the hellebore in this viscus, and on its decomposition, or is the venous absorption more active when a wound is made in the thigh, and some small veins have been consequently cut ?—Be it as it may, these poisons produce a slight inflammation, and exert an action on the lungs.
4th. Lastly, some of the poisonous substances of this class are rapidly absorbed, and give rise to vertigoes, violent convulsions, &c. phenomena which appear to partake both of excitement and stupefaction, and which depend on an immediate action upon the nervous system. They produce, besides, inflammation of the texture with which they come in contact: this is the case with Aconite.
It will be observed, without doubt, in the preceding propositions, that we admit the absorption of some of the poisons of this class, whilst at the same Mme we attribute the effects produced by the rest, to a sympathetic irritation of the nervous system. We believe we are able to explain the reasons which induce us to admit, or to reject their absorption.
A. It is evident that, if the poisonous substance when applied to the cellular texture, exerts only a slight local action, and produces, in a short time after its application, vomitings, vertigoes, convulsions, and death, in the course of a few hours, we ought to admit that it has been absorbed.
B. For a still stronger reason may we affirm, without fear of error, that the poisonous substance has been absorbed in the case where the application to the cellular texture has been immediately, or almost immediately, followed by symptoms more or less serious, terminated by death, and on dissection there are discovered inflammations in the lungs, or digestive canal, as takes place with tartar emetic, arsenic, and corrosive sublimate*. Again it appears certain that if has been absorbed, but in a slow manner^ when, being little soluble in water, its application to the cellular texture'is not followed by any remarkable symptom, till after the expiration of four and twenty, or six and thirty hours; death does not supervene before two or three days; and it has only exerted a local inflammatory action, not very violent, and which cannot be regarded as the cause of death.
C. It is also extremely easy to conclude, that it has not been absorbed, when its application to the cellular texture is not followed by any general symptom, and is confined to the production of an extensive slough. Thus we may cauterize repeatedly the limb of a dog with concentrated sulphuric acid, caustic potash, nitrate of silver, &c. several days will elapse before the animal will discover the smallest sign of derangement in the functions performed by the principal organs, and it is not till nature shall have excited an inflammation, in order to throw off all those parts which have become extraneous, that the animal can sink under the excess of pain.
D. But can it be concluded that the poisonous substance has been absorbed in cases where it produces a very violent inflammation in the cellular texture, with which it has come in contact, where death takes place on the first or second day, when the animal has not vomited, when no lesion of the principal organs is discovered after death, and nevertheless the substance is dissolved in water, and placed in the interior of the thigh, near to the lymphatic vessels, and a multitude of venous ramifications? .—Such is the question on which we wish to throw light, and it embraces a multitude of substances; for instance, Nitre, Euphorbium, Jatropha Curcas, &c. We are of opinion, 1st, that it is of no use to admit the absorption of any of these substances, in order to explain the phenomena they produce; 2nd, that it is probable it does not take place. The first of these propositions will appear evident, if we call to mind that the application of these sub
• My friend and pupil, Dr. Smith, has just published an excellent inaugural dissertation entitled, Essm sw U Danger de I'Application de» Caustiques; in which he proves that corrosive sublimate is absorbed, when applied to the cellular texture, and that it produces constantly inflammation of the stomach.