THE CHEMISTRY OF VENOMS 



CHAPTER II. 



THE CHEMISTRY OP VENOMS. 



THE presence of alkaloids in venom, and especially of the ptomaines, has been 

 suspected, and these bodies have been repeatedly sought for in vain. Gautier is 

 the only chemist \ve recall who asserts that he found a ptomaine in a venom 

 (Cobra). He does not state his processes, and we have been utterly unable to 

 substantiate his statements. Lest we should in some way have erred in the con- 

 duct of this part, of our labor, we asked Prof. Wolcott Gibbs to examine Crotalus 

 venom with a view to detection of such a body. As regards this search he makes 

 the following statement : 



" My investigation of rattlesnake venom had for its special object the comparison 

 of the venom with the higher alkaloids. As the quantity of material at my com- 

 mand was small, I was obliged to content myself with the application of the ordi- 

 nary tests used for the detection of alkaloids, as, for example, phospho-tungstates 

 and phospho-molybdates, iodide of mercury and potassium, etc. etc. In many cases 

 precipitates were obtained, but these were in no case distinctly crystalline. They 

 resembled, on the contrary, the precipitate formed by sodic phospho-tungstate in 

 solutions of albuminates in acetic acid. It seems, therefore, very improbable that 

 the venom contains an alkaloid in the sense in which that term is commonly 

 employed by chemists. On the other hand, it may still be basic in character, even 

 if it be classed with albuminoids, since these are known to combine with platinous 

 cyanide and with salicylic and other acids, exhibiting the properties of weak bases 

 as well as of weak acids." 



Venoms are of acid reaction, but when neutralized we have not observed any 

 precipitate in specimens of these poisons. 



When venom is taken from the Crotalus or Ancistrodon there is often observed 

 in the clear poison some insoluble whitish, granular matter, which soon settles to 

 the bottom. 



The Insoluble Precipitate. This insoluble matter, which we term the insoluble 

 precipitate, can be collected for examination by allowing the venom to stand in 

 hermetically sealed vertical tubes, as previously described. The precipitate soon 

 settles to the bottom, the clear venom is then carefully drawn off, and the precipi- 

 tate is repeatedly washed with distilled water and collected ; the washing process 

 is repeated until there is no trace of proteid reaction in the wash-water, or, in other 

 words, until all of the soluble portion of the venom has been completely washed 

 from the precipitate. 



When examined under the microscope this precipitate consists of irregular 



2 April, 1886. 



