ADSORPTION BY SUSPENSIONS OF VARIOUS SUBSTANCES. 217 



Eight mice injected with the residue died. The kaolin seems to hold the 

 adsorbed venom very loosely and the bond between the kaolin and the venom 

 is easily broken after the injection of the kaolin into a living organism. 



ADSORPTION OF VENOM BY ALUMINIUM OXIDE 



Two different samples of A1 2 O 3 were tested. Three mice injected with 

 the supernatant fluid obtained from the first sample (Eimer & Amend's pre- 

 paration) died as soon as their controls. This solution was found to give an 

 alkaline reaction. 



A suspension of a second sample of A1 2 3 gave a neutral reaction. In 

 this experiment 12 mice injected wth the supernatant fluid survived while 1 

 receiving 3J lethal doses died. On the other hand, 7 mice injected with the 

 residue of A1 2 O 3 died; 6 of these had been injected with the residue of the 

 second, 1 with the residue of the first (alkaline) sample of aluminium oxide. 

 It appears, therefore, that aluminium oxide adsorbs the venom very well, but 

 that here, as in the case of charcoal, the alkali interferes with the adsorption. 

 The venom is, however, only loosely held by the aluminium oxide. 



ADSORPTION OF VENOM BY OLIVE OIL. 



By prolonged shaking an emulsion was made of one volume of olive oil 

 in fourteen volumes of venom solution. All of the mice injected with this 

 fluid after separation from the larger oil droplets died as soon as their respec- 

 tive controls. It was found that centrifugation alone did not free the fluid 

 entirely of the finer oil droplets, and in order to obtain a fluid free from these 

 droplets the mixture was passed through a Berkefeld filter and the filtrate 

 injected into mice. All of the 6 mice injected with this filtrate ultimately 

 died after having survived their controls for considerable periods of time. 

 Furthermore, of 12 mice injected with the residue (containing both large and 

 small oil droplets) only one died. It is, therefore, probable that some venom 

 is adsorbed by the very fine oil droplets which are not separated from the fluid 

 by the centrifugation, but that the amount of venom adsorbed is very small. 



ADSORPTION OF VENOM BY LECITHIN. 



In testing the adsorptive power of lecithin, three specimens were used, 

 namely Merck's "Ovo," Kahlbaum's "Auseigelb, " and Agfa lecithin. In 

 each case 0.07 gram of lecithin was mixed with 7 c.c. of venom solution. By 

 rubbing the lecithin with small quantities of venom solution in a mortar a- 

 homogeneous, fine emulsion was obtained. Very fine particles of lecithin were 

 held in suspension in the supernatant fluid, even after centrifuging. It was 

 therefore necessary to filter the venom-lecithin mixture through a Berkefeld 

 filter in order to free the supernatant fluid from particles of lecithin. Both 

 the supernatant fluid obtained after centrifuging and the filtrate which had 

 passed through the Berkefeld filter were tested. 



Experiments with the supernatant fluid, decanted from the centrifuge 

 tubes, showed that Merck's "Ovo" lecithin as a rule adsorbed somewhat less- 

 than 70 per cent of the venom; at times, however, it adsorbed somewhat more. 



