OF THE VENOM OF THE U A T T L E S N A K E . 35 



Tlius far we have only learned, from the preceding details, that the venom of 

 the Crotalus is an acid-lliiid, abounding in albuminous matter, and yielding preci- 

 pitates, or coagula, with certain reagents. 



It was highly probable, for various reasons, that the active element of the venom 

 was to be sought in the albuminx)id compound just referred to. Accordingly, the 

 greatest attention was paid to this substance, and at every step in the analysis 

 the coagula and filtered solutions were studied toxicologically, as well as chemically. 

 Prince Charles Lucien Bonaparte has given us the only analysis of a snake venom 

 with which I am acquainted ; it is that of the viper. I have been unfortunate in 

 not having had access to the original Essay of this observer, and have been forced 

 to content myself with such analyses of his paper as are to be found in the sys- 

 tematic works on poisons, and in one of M. Bernard's recent volumes.^ Thus 

 aided, I have partially followed M. Bonaparte's method of analysis; but have found 

 it insufficient for the thorough examination of rattlesnake venom. 



The observations and analyses which I have thus introduced, were conducted in 

 the following manner : — 



1st. Ten or twelve drops of pure Crotalus venom were secured, as usual. Of 

 this, a minute amount was employed as a toxicoiogical test of the activity of the 

 specimen about to be studied. 



2d. The remainder of the venom was mixed with two drachms of cold water, and 

 thoroughly boiled for five or ten minutes. A dense coagulum took place, and settled 

 quickly, leaving above it a pearl-colored fluid, free from sedimentary matter. On 

 shaking the test-tube, so as to mingle the coagulum and the supernatant fluid, and 

 then injecting one-half into the breast tissues of a pigeon, it was found that the 

 mixture proved speedily fatal. Boiling had not destroyed its power. 



3d. The remaining half of the mixture (coagulum and fluid), was cast on a 

 small filter, and when the pearly fluid had passed through, the coagulum which 

 remained was carefully washed, drop by drop, with cold water. On the filter was 

 finally left the white coagulum, thoroughly washed ; in the filtrate were all the 

 parts of the venom which could be dissolved either in cold or boiling water. 



4 th. The toxicoiogical test was now introduced, to decide whether the poisoning 

 activity lay in the cbt formed by heat, or in the separated fluid. Upon numerous 

 repetitions of this observation, it invariably happened that the coagulum was inno- 

 cent, and that the pearly supernatant fluid, with the washings of the coagulum, 

 was a deadly poison. The experiments were made as usual, by injecting the venom 

 into the breast or leg tissues of healthy pigeons. 



5th. As I was aware that alcohol threw down all of the albuminoid elements of 

 venom, it occurred to me that it might also precipitate from the boiled venom the 

 material which appeared to escape the coagulating influence of the heat. Accord- 

 ingly, a considerable quantity of venom, about fifteen drops, was boiled, m half an 

 ounce of water. When the coagulum settled, the opalescent supernatant liquid was 

 decanted with care, the coagulum washed on a filter, and the washings mixed with 



• Orfila, Toxicologie Generale, Art. Tlpfere. Bernard CI. Le5ons sur les Eifets des Substances toxiques 

 et mudicamenteuses. Paris, 1857, p. 393. Nysten, Diet, de Medecine, Art. Echidnme. 



