212 BIO-CHEMICAL JOURNAL 



the sense of an increase but a decrease, so that there is a disappearance 

 of ions. This result is, I think, what would be expected from our 

 knowledge of the relation of calcium to clotting, and the observations 

 of E. G. Martin must be explained in another way. My experiment 

 was made on fowl's blood. As shown by Delezenne, if kept from 

 contact with the tissues this blood remains unclotted for a long time. 

 It was collected from the external jugular vein and placed in a U tube 

 furnished with an electrode in each limb and immersed in a water- 

 bath at io - 2 C. When the temperature had become constant the 

 specific conductivity of the blood was 5382 gemmhos. A small piece 

 of muscle from the fowl was then dropped into one side of the tube. 

 The conductivity steadily fell to 4360 gemmhos, which value was 

 attained in 40 minutes ; no doubt the process was completed earlier 

 than this, but it was not wished to disturb the apparatus until it was to 

 be expected that. clotting had ocurred. The diminution of conductivity 

 therefore amounted to 18-5 per cent, of the original value. 



6. Action of enzymes 



I do not purpose here to enter into this subject in any detail, 

 since it will be dealt with fully in a forthcoming paper. 

 There is a certain amount of evidence that the splitting-ofF of 

 inorganic constituents contributes to the rise of electrical conductivity 

 observed in many cases, but the direct proof was found to be of 

 considerable difficulty. 



In the action of rennet on milk, I find a slight increase of con- 

 ductivity. This is merely an additional fact showing the nature of 

 this process to be quite different from that of clotting of blood. In 

 all probability rennet-action is only an expression of pepsin-action in 

 neutral or faintly alkaline medium. 1 



VI. SPECIFIC ADSORPTION 



The phenomena of adsorption show in this respect an approxi- 

 mation to true chemical combination. 



It was shown by Schonbein* that when strips of filter-paper were 

 immersed in solutions of various salts that the height to which the salts 



1. Pawlow and Parastschuk. Hoppe-Seyler' ZeitscA.,'^'2, p. 415, 1904. 



2. Poggendorff, Ann., 114, p. 275, 1861. 



