ADSORPTION BY SUSPENSIONS OF VARIOUS SUBSTANCES. 215 



ADSORPTION OF VENOM BY ANIMAL CHARCOAL. 



In testing the adsorption of venom by animal charcoal, both fresh and dry 

 venom were used. In the case of the fresh venom we added quantities of char- 

 coal equal to one-half, one-quarter, and one-sixteenth of the volume of the 

 venom solution and found, after these mixtures had been shaken for 2 hours 30 

 minutes, that all the mice injected with the supernatant fluid survived the injec- 

 tion. In an experiment in which a quantity of charcoal equal to only one 

 thirty-second of the volume of the venom solution had been added, the adsorp- 

 tion was incomplete, and two mice injected with the supernatant fluid from 

 this mixture died as soon as their respective controls. Quantities of charcoal 

 equal to one-sixteenth of the volume of venom solution are, therefore, sufficient 

 to adsorb all or almost all of the venom; while a quantity of the charcoal equal 

 to one thirty-second of the volume of the venom solution adsorbs less than half 

 of the venom. 



In experiments in which the time of contact between the venom and the 

 charcoal was shortened to 15 minutes, the adsorption was not complete and 

 animals injected with two or four lethal doses of venom died. Throughout 

 subsequent experiments we used solutions of dry venom with a quantity of 

 charcoal equal to one-sixteenth of the volume of the solution. Only one 

 mouse of the sixteen injected with quantities of this supernatant fluid died as 

 a result of the injection, even when amounts corresponding to 13|, 6f , and 3^ 

 were administered. This mouse injected with a quantity of the fluid corre- 

 sponding to 6f lethal doses lived, however, longer than the control mouse, 

 which had received a similar quantity of the pure venom solution. 



Charcoal not only adsorbs all, or almost all, of the venom, but moreover 

 it holds the adsorbed venom very firmly. Eight mice injected with 2 c.c. of a 

 suspension containing the residue of the charcoal-venom mixture survived the 

 injection. It is not probable that the venom was removed from the charcoal 

 during the washing with salt solution. 



The addition of 2 drops of decinormal hydrochloric acid to 7 c.c. of venom 

 solution interfered with the adsorption of venom by the charcoal in only one 

 experiment and then only to a slight extent. Nineteen mice inj ected with the 

 supernatant fluid of this mixture survived the injection, but two mice injected 

 with quantities corresponding to 13i lethal doses, two injected with 6f andone 

 injected with 3| lethal doses, died. These five mice had all been injected 

 with the same solution, and their death was the only instance in which any of 

 the mice injected with the supernatant fluid died. Of theeleven mice injected 

 with the residue, only two died. The addition of weak acid to the venom- 

 charcoal mixture may, therefore, cause the bond between the charcoal and the 

 venom to be more easily broken after the injection of the residue into a living 

 organism. 



In other experiments we added first two drops of decinormal sodium 

 hydroxide and subsequently the usual volume of charcoal to 7 c.c. of venom 

 solution. Of 21 mice injected with the supernatant fluid, 1 died as soon as the 



