226 BIO-CHEMICAL JOURNAL 



as calcium, should increase the adsorption. In some preliminary 

 experiments I have made there seems to be some action of this kind, 

 but it is difficult to obtain the correct relative concentrations so as to 

 avoid precipitation. An experiment was also made on adsorption of 

 trypsin by paper as follows :-- 



Four crystallizing dishes were taken, each containing a circle of 

 filter paper, in two of them there was a watery solution of trypsin, in 



the other two a solution of trypsin of the same strength in ^ c a so 4 . 

 After standing in a cool place for 24 hours, a paper trom the watery 

 solution was taken out, drained for I minute, placed in a flask, and 

 heated to ico in a steam sterilizer ; the same was done with a paper 

 from the CaSO 4 solution. 160 c.c. of 5 per cent, caseinogen in ammonia 

 were added to each, and they were then placed in the thermostat at 

 39 ; when warmed to the first was added a drained paper from the Caso 4 

 trypsin, and to the second a similar one from the watery solution. 

 The electrical conductivities were determined at intervals. There was 

 not a very great difference between the two, but what there was showed 

 that rather more trypsin had been taken up by paper under the action 

 of Caso 4 . The times taken to reach a change of 800 gemmhos were 

 165 minutes for the trypsin from c a so 4 solution, and 192 minutes for 



that from watery solution. A similar experiment taking a ~ solution 

 of toluidini-blue instead of CaSo 4 was unsuccessful on account of mutual 

 precipitation of the dye and trypsin. The precipitate, when filtered 

 off and washed, showed itself to have considerable tryptic power. 

 This subject requires further investigation. 



The importance of the study of adsorption and surface-action in 

 general in connection with the enzyme-action is emphasized by Bredig 1 

 in his article on * Chemical Kinetics ' in the Ergebnisse of Asher and 

 Spiro. 



8. Oligo-dynamic action 



It has been pointed out by Pauli* that the puzzling phenomena 

 called ' oligo-dynamic action ' by v. Naegeli, and consisting in toxic 



1. Ergebnisse d. P/iysiologie, I, p. 211, 1902. 



2. Hofmeister's Beitrage, VI, p. 257 (footnote), 1905. 



