276 "SPECIFIC TREATMENT" OF DISEASE 



swimming spiral threads upon a dark background. 

 The presence of spirochaetes in the primary sore of 

 syphilis, in the secondary skin eruption, and in the 

 tissues of persons affected by tertiary syphilis, is of 

 positive value in diagnosing the disease. It ensures 

 the early diagnosis of the disease and prompt re- 

 course to treatment. Apart from this a most use- 

 ful means of diagnosis based on similar work by 

 other observers was introduced by Wassermann; 

 this is known as the "complement deviation test," 

 but a description of the test need not be considered 

 here, since it would lead the reader too far afield. 



The discovery that syphilis is communicable to 

 animals, coupled with a knowledge of the character 

 of the infective spirochaete, at once gave hope of 

 a rapid advance in the study of the disease. Al- 

 though syphilis had doubtless been experimentally 

 produced in monkeys and even in rabbits before 

 the date of these discoveries, the mild and atypical 

 effects observed could not be certainly determined 

 as representing true syphilis. The discovery of the 

 spirochaete changed this completely by rendering 

 diagnosis certain. 



At this point Ehrlich threw himself into the 

 study of syphilis and sought to find a cure for the 

 disease experimentally induced in animals. In due 

 course he found a remedy in an arsenical compound 

 which became known as "606" or "salvarsan." 

 Similar drugs are now manufactured in different 

 countries under various names which need not be 



