82 



PHYSIOLOGY AND TOXICOLOGY 



that a tube of sufficient size was placed in it before the bite, so that no time might 



be lost. 



The animal was struck twice in the left thigh at 4.20 P. M. At the seventh 

 minute it fell, and at the thirtieth minute, the respiration being very feeble, artificial 

 respiration was made, and the chest opened. The heart was acting well, but not 

 perfectly, the same want of completeness in its systole being seen as was noticed in 

 former cases. At the close of the sixtieth minute from the time of the bite, the 

 organ became more markedly feeble, and the ventricles acted but rarely. In this, 

 as in all other like observations, the heart remained irritable to galvanism for a 

 short time after it ceased to pulsate, and locally responsive for a still longer period. 

 It was plain, enough from these experiments that the artificial respiration was 

 capable of prolonging the cardiac functions, but not usually for any great length of 

 time. Moreover, the heart was always found beating in animals poisoned, and 

 opened as soon as respiration ceased. Again, its tissues were always alive to 

 stimulus for a short period after its rhythmic movements stopped, so that there 

 was evidently no such complete local paralysis of the muscular structures as is 

 caused by upas-antiar or corroval. When an animal is poisoned with these last- 

 mentioned substances, death begins at the heart; and so complete is the palsy of 

 this organ, that the most violent galvanic stimulus fails to provoke in it tlie least 

 response, even when applied immediately after it has ceased to pulsate rhythmically.* 

 These views were strengthened by the following experiment : Being aware that 

 the young of warm-blooded animals approximate to the condition of cold-blooded 

 creatures, in regard to the comparative independence of their cardiac and respira- 

 tory functions, I exposed several kittens of a week old to be bitten. As soon as 

 respiration ceased their hearts were laid bare, and found to be beating quite 

 actively. Thus, in one case, the kitten was bitten thrice, by as many rather ex- 

 hausted snakes, between three minutes of six, and eleven minutes after six. 



At G.19 P. M. sensation was gone in the limbs; and at 6.23, all motion ceased, 

 except occasional diaphragmatic acts. At G.25, the dorsal spine was divided, and 

 no movement took place, the left sciatic remaining perfectly irritable. During this 

 time the heart continued to act regularly, and at 6.44, was still able to respond to 

 stimulus by feeble, but repeated pulses; one stimulation being followed by three 

 or four complete pulsations. 



In all human cases of Crotalus poisoning, the general feebleness which follows a 

 severe bite is most notable. As we have seen, there is reason to believe that at 

 least a part of this deadly prostration may be due to an effect on the heart, while 

 on the whole, there is not reason to suppose that its tissues are so paralyzed as to 

 permit us to assert that death begins at the cardiac centre. 



As it was possible that I might be deceived as to the appearance of lack of power 

 in the heart, I subjected the matter to more accurate examination. For this pur- 

 pose, I instituted the following experiments : — 



Experiment. — A large brindled dog was properly secured on the table, and his 



• See a paper on new varieties of woorara by Prof. Hammond and the author, Amer. Jour, of the 

 Med. Sci., July, 1859. 



