7 
The syringes are prepared and filled in a special room where the 
exact measuring’ is done, and the rack is then found handy to carry the 
s}"ringes to the animal room, where the work of injection is carried on. 
In standardizing diphtheria antitoxin we always inject a total of d c. c. 
of fluid, allowing only one washing, but when the total amount of 
fluid injected is immaterial, especially in larger animals, the syringe 
may be washed out several times with a neutral fluid. 
In using this method in standardizing diphtheria antitoxin it is 
important to shake and roll the syringe so as to obtain an intimate 
mixture of the toxin with the serum. 
In working with definite weights of solids the solution may be made 
in the barrel of the syringe, so that the method is applicable in any 
sort of work where it is important to inoculate animals with precise 
amounts. 
O 
