OF THE VENOM OF THE RATTLESNAKE. 27 



CHAPTER IV. 



THE PHYSICAL AND CHEMICAL CHARACTERS OF THE VENOM. 



TnE venom, the injection of which is the sole object of the mechanism we 

 have been considering, will now claim our attention. In my own researches, I 

 have felt seriously the want of statements as to the manipulation and mechanical 

 means employed by preceding observers, when handling, and otherwise using, their 

 snakes. For this reason, as well as to place the reader upon the same logical 

 ground with myself, by giving him every known condition and accompaniment of 

 each observation, I have, in all cases, described minutely the whole manual of 

 each experiment. Where these details would have confused the statements of 

 results, I have placed them in the form of notes. 



It would have been an easy task to swell this Essay to an imposing bulk, by 

 quoting throughout all the comparative results obtained by those who have expe- 

 rimented on venomous snakes, other than the Crotalus. So full a summary would 

 not be without use and interest; but, since the mass of these researches have but 

 little value, I have contented myself with the briefest relation of the opinions of 

 others, where they did not directly concern the rattlesnake. My main object has 

 been to present, with brevity, my own results, as regards the Crotalus, with such 

 illustration, contrast, and comment, derived from the works of others, as seemed 

 to me essential to this purpose. 



A^noimt of Venom in the Duels.— The amount of venom contained at any one 

 time in the ducts of the poison gland, varied with the size of the snake, and the 

 period which had elapsed since the last bite. I have again and again collected 

 the venom, and have found that serpents of from three to four feet long rarely threw 

 out more than from two to four drops, after the first ejection had taken place. 

 When perfectly fresh, healthy, and undisturbed for some weeks in summer, the first 

 gush of their venom was sometimes astonishingly large. A snake which had served 

 as a show in Washington, reached me in a box with a glass top, which was firmly 

 fixed by screws. In all probability this snake had been several weeks without using 

 its fangs.^ It was secured as usual, and the lip of a cup placed in its mouth. It 



' Manipulation.— The authors who have written upon serpents, have usually obtained their venom 

 by kiUing the animal, and compressing the gland (Fontana), or by anaesthetizing it with chloro- 

 form (Burnett), and then exerting pressure, until the fluid exuded through the duct. Where snakes are 

 abundant, the first method is perhaps the best, if the head be cut off rapidly and suddenly, without 



