26 THE VENOMS OF CERTAIN THANATOPHIDEi!. 



Experiment. — Boiled 0.015 gram dried Coral venom dissolved in 1 c. c. distilled 

 water. 



Time of injection ? 



5:45. Very weak. 



6:00. Nearly dead. 



6:10. Dead. No local effects. Blood coagulates perfectly. 



A smaller amount of venom unboiled kills in from 10-15 minutes with decided 

 local effects. 



From the experiments with the venom of the Crotalus adamanteus detailed above 

 it appears as though the toxicity of the venom was completely destroyed by boiling, 

 but Weir Mitchell found some years ago that boiling did not destroy the poison- 

 ousness of the venom of the Crotalus durissus, and further work of our own led us 

 to believe that the want of toxicity of our boiled solutions was only apparent, and 

 that there was accordingly a poisonous principle still present, but not in deadly 

 quantities. We therefore made some further observations, using larger amounts of 

 venom. 



Experiment. — Dissolved three drops of fresh Crotalus adamanteus venom in 1.5 

 c. c. distilled water and boiled. 



4:40. Injected into the breast muscles of a pigeon. 



6:10. No positive effects. 



Following morning. Dead, no characteristic local effects. 



Experiment. — Dissolved 0.12 gram venom {Crotalus adamanteus) in 2 c. c. dis- 

 tilled water and boiled for two or three minutes. 



4:40. Injected the above into two pigeons, giving each half. 



Death within fourteen hours in both pigeons. There was some slight local effect, but 

 nothing comparable to what is observed in the unheated venom. There were no extravasa- 

 tions, and the blood was clotted. The stench from putrefaction at the points of injection 

 was very great, and the muscles around them presented a pale-grayish color as though they 

 had been boiled. 



A like result was obtained in the case of another pigeon experimented on in the 

 same way. 



From the above series of experiments it is perfectly clear that heating the dis- 

 solved venom beyond a definite point, varying no doubt in different venoms, lessens 

 its toxic power. Boiling for some minutes does not destroy the poisonous capacity 

 of the venoms, but simply impairs this quality to a varying degree, depending upon 

 peculiarities in the toxic constituents, as we shall hereafter have reason to observe. 

 Fayrer and Wall, as already noted, found that prolonged boiling of solutions of 

 Cobra venom completely destroyed the poisonous activity of that secretion. We 

 accordingly made some similar experiments with solutions of the venom of the 

 Crotalus adamanteus with analogous results. 



Experiment. — 0.03 gram of the dried venom of the Crotalus adamanteus was 

 dissolved in a little distilled water and boiled for ten minutes in a water bath 

 After being allowed to cool it was injected into the breast of a pigeon. 

 1:56. Injection practised. 

 1:51. Weak. 

 2:00. Convulsions. 



2:37. Since last observation has been lying on its side, very weak. 

 2:43. Dead. 



