MEIER S MODIFICATION OF THE WASSERMANN TEST 



through gauze to remove the very large particles. The filtrate is then ready for use. 

 It is light or dark brown in color, and translucent even in weak dilution. On standing, 

 a brown sediment settles to the bottom; before being used the extract should be 

 thoroughly mixed as in this way it is five to ten times stronger than if the supernatant 

 clear fluid alone is taken. 



The efficiency of the extract is proven in two ways: i. The orientation or qualita- 

 tive test, to determine whether the new extract is specific for lues. 2. The quantitative 

 test, to determine the exact dosage necessary for complement fixation. (See Table I.) 



Thus it is observed that for both of these standard sera (positive and negative) 

 this extract can be employed in two doses 0.05, 0.025. 



The next step is to determine which of these two doses is the more efficient for the 

 greatest number of sera. The largest quantity of antigen is always preferred; but it is 

 a known fact that the optimum for one serum is not equally that for another serum. 

 Accordingly, parallel examinations are made of a great number of sera, employing 

 both the new antigen and the old control one, which has already been tested out and 



II (Quantitative Test) 



