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all folks the most sceptical, is thus far was noted as being forty-five to the unconvinced of its value, and awaits the minute. In three minutes it was unalresults of a larger number of cases; tered as to number, but had become irfeeling, meanwhile, at full freedom to regular. Then it began to fail, beating test its possible utility in a disease so thirty at the fifth minute, and ceasing unconquerable by ordinary methods. half a minute later, the auricles con

The poisonous agents which have tinuing somewhat longer. As the organ power to destroy life by acting directly failed, a strange fact was noted; at the on the heart are numerous. Among instant when the great cavity of the them we find aconite and digitalis well heart — the ventricle – contracted so known as medicines, and useful to con- as to expel the blood into the arteries, it trol tumultuous or over-excited activity was observed that here and there on its in this essential organ. Several, also, surface little prominences arose, which of the Eastern arrow poisons belong were presumed to be due to these parts to this class, -as the upas, of Borneo; being palsied so that they yielded unand, finally, the corroval, an arrow poi- der the pressure from within. That son of the Isthmus of Panama.

this was a true view of the case was To point out precisely in what way shown by pinching or galvanizing these various agents influence the heart minute portions of a healthy, active would require us to explain at length heart, when the same appearances were the whole physiology of this organ, and noted at the points enfeebled by the to discuss the function of the different over-stimulation to which they had been nerves which enter it. We shall there- thus mechanically subjected. When fore content ourselves with relating the heart stopped, it could not be re-exwhat is known in regard to corroval, cited by a touch, or by electric currents,

- a poison which thus far has been as was the case in woorara poisoning, investigated only by two American tox- or in death from violence. icologists. Like woorara, this sub- During all of this time, and for twenty stance is a resinous-looking material, minutes after the heart ceased to beat, which is certainly of vegetable origin. the frog leaped about with readiness and It is used as an arrow poison by the ease, so that it seemed pretty clear that dwellers on the Rio Darien, but of the corroval was a poison which paralyzed nature of the plants which yield it we directly the tissues of the heart, without know absolutely nothing. Thus far it at first influencing any other portion is known only to savages, and to two of the economy. To put this beyond or three students of poisons, nor, if it doubt, the experimenter tried to keep were used to kill man, would it be pos- up the circulation by causing artificial sible to detect it in the tissues. As in breathing, which in the case of woorara the case of woorara, let us relate briefly was competent to sustain the heart's achow the toxic characters of corroval tion. Here, however, the heart stopped were first investigated.

as though no such means had been used. A frog was held while the opera- The same observation may be better tor placed a morsel of poison in a wound made on the young alligator, because made in the back. In ten or twelve in this creature the breathing continues minutes it showed signs of lassitude, for some twenty minutes after the heart and in half an hour was totally mo- has ceased to pulsate, thus making it tionless and dead. Nothing was seen

still more clear that the heart does to lead to the belief that the toxi- not die owing to defect of respiration. cologist was dealing with a substance Lastly, it was shown that when in a differing from common woorara. The healthy frog the heart is cut out, or its outward signs were alike. A second vessels tied, voluntary and reflex motion frog was then poisoned, after a little disappear at about the same period as V-shaped opening had been so made as they do when corroval has been given ; to expose the heart, whose natural beat whence it was inferred that this agent

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destroys the general movements only it seemed to have been vomited, as to because it first interrupts the circulation which operation as possible in a frog of the blood, without which they soon nothing had been hitherto known. The cease to be possible.

following day a full dose of corroval in The contrast between woorara and a little alcohol and water was poured corroval is very striking, since in the through a tube into the stomach, when former the heart dies last, and in the instantly this organ was inverted, and latter it is the first organ to suffer. pushed up through the wide gullet and

We are aware thus far of scarcely a outside of the mouth, where the frog poison which acts entirely on a single presently cleaned it most expertly with organ. In every case it has been found its fore legs. Its return was gradual, that the noxious effects are finally felt and over this act the creature seemed by other parts in turn; and, so far as we to possess no voluntary control. can gather, these secondary poisonings As the power to turn the stomach are direct effects of the poison in many inside out is rarely exercised, and therecases, and not merely results of the fore not anticipated, the reader may death of the organs first injured. Thus, understand how easily it might deceive, while pointing out that in the reptile if a poison having been given it were voluntary motion exists after the heart thus disposed of in the experimenter's stops, but soon ceases on account of absence. the arrest of circulation, we might have A favorite mode of suicide in France added, that, by a variation in the mode is to breathe a confined atmosphere in of experimenting, it can be made clear, which is burning a pan of charcoal. that where, owing to a small dose of For a long time it was supposed that, the poison, death comes slowly, the under these circumstances, the death sensitive nerves first, and then the mo- which ensued was due to the carbonic tor nerves, and last the muscles, are all acid set free as one of the products of directly and in turn affected by the poi- combustion, in which case we should son. Finally let us add, that, given by have asphyxia from deficiency of oxygen the mouth, this agent usually causes and excess of carbonic acid, - a mode of convulsions, such as do not appear if death as well understood as any death the poison be put under the skin,-a can at present be. fact for which we cannot in any way ac- When, however, attention was called count, but which aptly illustrates how to the presence of another gas, in the easy it is to deceive one's self where mixed products of incomplete combussuch variations may arise in the symp- tion, the toxic characters of this agent, toms caused by one and the same now known as carbonic oxide, became poison.

subjects of inquiry. After several theAs an apt illustration of the difficul- ories had been set forth, only to be ties which surround this study, it may pushed aside by the next comer, Claude not be out of place to mention the fol- Bernard re-investigated the matter, lowing incident. During the study of and, with his usual happiness in discorroval it became desirable to learn covery, pointed out what is, at least the rate at which this material could for the present, a well-accepted explabe absorbed from the stomach. Accord- nation of the mode in which this gas ingly a weighed morsel was pushed poisons. down the wide gullet of a large frog and Here for the first time we deal with into its stomach. The animal being left an agent which enters the blood through in a vase with a half-inch of water, the the lung. Six hundredths of the volnext day it was alive and well, to the ume of an atmosphere, the rest of which operator's surprise. Repeating the ex- is common air, is fatal to a bird conperiment, the frog was left under a bell. fined within it. The death is rapid, and glass, on a dry plate. This time the usually convulsive. Upon examining corroval was found on the plate, so that the body of the poisoned animal, we are struck with the brilliant red color of the Healthy blood shaken with carbonic blood; and if at the same time we com- acid becomes dark, and fresh contact pare the appearances seen in a bird with the air will redden it again. When killed by carbonic-acid gas, we shall once it has been poisoned by carbonic be still more impressed with the differ- oxide, such changes are no longer posence, because this latter gas colors the sible, simply because the blood-globules blood of a very dark hue.

have grown incapable of taking up any To make clear what is to follow, the gas but the one which has poisoned reader should carry in mind the follow- them. ing facts. The blood, in circulating, Neither can we cause them in any goes through the lung, and there gives way to give up the hurtful carbonic oxup carbonic acid, and, receiving oxygen ide which has taken possession of them. from the air, becomes bright red. Thus A fatal attachment has been formed, altered it is forced by the heart along and they refuse to return to their everythe great arteries, until, finally entering day duty. the minute vessels called capillaries, it The careful and elaborate series of has between it and the tissues only analyses and experiments which brought walls of the utmost thinness. This Bernard to this conclusion it would be vast mesh of tiny tubes makes the folly to attempt to make clear to any great markets of the body, in which but the physiological chemist. So far occur a host of exchanges, of givings they have not been set aside by any and gettings on the part alike of blood more authoritative verdict. and tissues, such as muscle, nerve, Here, then, we have the curious case and bone. The most important of of asphyxia, or death from want of oxythese is the taking of oxygen by the gen, not because the lungs have ceased tissues, and the giving up of carbonic- to present it to the blood, but because acid gas to the blood. The first gas is that fluid has become unable to accept needful for a multitude of purposes, the gift. Hence results sudden cessawithout which life must cease; the sec- tion of every function which demands ond, when retained, is poisonous; and, as for its continuance unceasing change in the interchange depends for existence the tissues which effect it, and so death upon there being two gases, the loss of follows as a matter of course. a hurtful one is made subservient to the I cannot hope that to any but very getting of a useful one. Moreover, as careful readers I may have been so the little blood rivers flow by nerve and happy as to make clear the history of bone, the materials which these must these three poisons, as they act within get rid of as the results of their waste the body, and sunder one or another of are cast for the most part into the gen- the many essential links which make the eral volume of these streams; but, as complete chain' of life. One abolishes regards the gases, we find them trans- the power of the nerves of motion ; ported chiefly on or in the blood-glob- one palsies the muscles of the heart, ules, which float in myriads along these and one annihilates the function of tiny streamlets. In the tissues they the red blood-globules. These diverse each get a load of carbonic acid, of modes of destructive activity are but which they lose the most in the lungs, instances of the wonderful variety of replacing it with oxygen, and so are modes in which the fortress of life may continually voyaging to and fro betwixt be assailed. the sources of supply and demand. The reader will not fail to have noImagine for a moment these millions ticed that two of the three poisons here of little carriers become incapable of discussed are of comparatively recent transporting their destined freights, introduction. The same statement apand such precisely is what occurs when plies to the two best-known kinds of an animal is made to breathe carbonic upas, and to a third, admirably studied

by Dr. William A. Hammond, while the

oxide gas.

same may be said of Calabar bean and cessible poisons are sure to be detected other poisons used by savage tribes. by the chemist, that I have no doubt Scarcely one of these could as yet be this alone has tended to lessen their detected in the body of man, were it fatal use. The question of the relative employed to destroy life; so that it is ease with which poisonous drugs may as well that these dangerous agents be obtained leads to some reflections should be carefully guarded by the toxi- which have especial application in our cologists into whose hands they may own country chance to fall. A recent writer in these In Europe, and particularly on the pages, alluding to this subject, also Continent, the sale of poisons is surpoints out that the same difficulty in de- rounded by the most stringent precautection applies to many of the poison- tions, so that it is very difficult to proous substances which every year are cure them without a physician's premade by chemists engaged in the study scription ; the doctor, as it were, coming of complex organic compounds. Some between the apothecary and the public, of the bodies thus discovered are of the to guard the latter from crime or injury. most deadly character; so that here Here, however, the utmost laxity preagain it is well that the awful power vails, and although in some States rigid which they give should rest in the keep- laws on the subject exist, they are daily ing of the trustworthy men of science disobeyed by almost every druggist, whose industry has brought them to – the slightest excuse enabling almost light. Poisoning, as a rule, has been a any one to buy corrosive sublimate, arcrime of the intelligent classes, rather senic, or opium. It is time that some than of the poor, or of those whose effective measures be taken to check passions, being under less certain gov- this evil, which not only invites to, ernment, are apt to seek gratification crime but removes all restraint from by the most direct means. Of late, those who desire to intoxicate themhowever, it has become so well known selves with opiates, ether, or chloroto educated persons, that the more ac- form.

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