88 



rilYSIOLOGY AXD TOXICOLOGY 



move. On dividing the sciatic nerves, free motion was observed, and the phrenic 

 trunk was likewise irritable. 



In another set of cases, the centres and nerve-trunks were galvanized immediately 

 after the natural respiration ceased, and before the heart was quite at rest. Still, 

 the same results were observed, so that it became clear that death took place rather 

 from paralysis of the centres than from loss of function in the efferent nerves. 



The duration of irritability in the motor nerves of the frog was observed to be 

 less under venom poisoning than under death by decajjitation, for example. It is 

 to be borne in mind, however, that where the heart ceases to beat, or beats too 

 feebly to circulate the blood, the loss of nerve power may be due to this cause 

 alone, as Kolliker has very well demonstrated. Yet, as we have seen, this source 

 of Mlacy may be readily eliminated. 



Effect of the Venom ujion the Calorifacient Functions.— In very acute cases of Cro- 

 talus poisoning, death may occur so suddenly as to preclude the possibility of a fall 

 of temperature. The following experiment is a fair type of what occurs in most 

 cases which do not perish within a few minutes. 



^a;pera«eni;.— Temperature of the air 72° F. At eight minutes to five P. M., a 

 very accurate thermometer capable of indicating tenths of degrees^ was placed in 

 the cloac of a pigeon, and was found to mark 108° F. As the pigeon became 

 tranquil, it fell to 107.5° F. The pigeon was then exposed to the bite of a snake 

 two and a half feet long. Great quivering of the muscles ensued. 



At the tenth minute, the temperature was 107.2° F., respiration 31. 



The following record was then obtained : — 



Time after death. Temperature. 



14th miuute 10G.8° 



19tb " 105.5 



22d " 105.8 



25tli " 104.8 



28th " 104.3 The bulb at this time slipped a little further into the cloac. 



31st " 104.4 



34th " 104.4 



S'lth " 104.2 Eespiratiou 40. 



40th " 103.9 Respiration jerking. 



43d " 103.5 



46th " 10.3.3 



49th " 103.1 



52d " 103. Respiration 52. 



55th " 102.5 Slight convulsions. 



58th " 101.5 Respiration irregular and slow — 12. 



61st " Respiration ceased. 



62d " 101.3 



63d " 100.9 



66th " 100. 



• This instrument was made by J. W. Queen & Co., the well-known opticians, No. 924 Chestnut Street, 

 Philadelphia, to whom I am indebted for much valuable aid in making and altering the numerous instru- 

 ments which from time to time have been necessary in various physiological researches. 



