FORMATION OF DEFENSIVE FERMENTS 



75 



the behaviour of the serum towards cane sugar. 

 To i c.c. of serum was added i c.c. of a 10 per cent, 

 solution of cane sugar and 5 c.c. of normal salt 

 solution. The initial rotation of the mixture was 

 + 0*45. At the end of the experiment the rotation 

 had sunk to - 0*50 (see fig. 4). 



(2) Blood was taken from a dog before the paren- 

 teral introduction of cane sugar, and the behaviour of 



Hours 



5 JO 12 IV Iff 



20 ZZ 21 26 2d 3O 35 W tS SO 



FIG. 4. 



the serum towards this disaccharide was ascertained. 

 Decomposition did not take place (curve i in fig. 5). 

 Then 10 c.c. of a 5 per cent, solution of cane sugar 

 were given to the animal by intravenous injection. 

 The sample of blood, taken fifteen minutes after the 

 injection, already showed hydrolysis of the cane sugar 

 that had been added (curve 2 in fig. 5). For the pur- 

 pose of control the rotation of the serum without the 



