130 APPLIED IMMUNOLOGY 



amboceptor paper and washed corpuscles from the pa- 

 tient. But it was soon found that the complement 

 paper rapidly lost its power and became useless, lead- 

 ing Noguchi to discard it in favor of fresh guinea-pig 

 serum. The antigen and amboceptor papers are still 

 employed to some extent, but accurate titrations of the 

 reagents cannot be carried out when they are used, and 

 misleading results are liable to occur. Reliable 

 workers employing the Noguchi system now use the 

 different reagents in their original fluid form, titrat- 

 ing them accurately, so that the technic as carried out 

 at present has no advantage over the original Wasser- 

 mann in point of simplicity. Those accustomed to the 

 Noguchi modification with careful titration of all the 

 reagents, no doubt obtain as reliable results as can be 

 obtained with the Wassermann technic, and even 

 claim that the results are more delicate. We believe, 

 however, that by proper titration and employment of 

 a minimal amount of complement, there will be little 

 difference in the results obtained by the two methods. 

 As in all laboratory procedures, cases will be en- 

 countered on the border-line between positive and 

 negative which can only be judged by a consideration 

 of the clinical features of the cases, and the experience 

 of the worker. 



Hecht'Weinherg 3Iodification. — The Hecht- 

 Weinberg test modifies the Wassermann reaction for 



