The demonstration of antibodies in the circulating blood by complement fixation was first accomplished by Bordet and Gengou1 and its application was made to tuberculosis by them several years before Wassermann and Bruck successfully applied the test in syphilis. If medical men should desire a less cumbersome term than the complement fixation test for tuberculosis it seems they could not do better than to term it simply "the Bordet test." The term has the advantage of brevity. It is historically accurate, and would fittingly perpetuate the name of the distinguished French investigator who first demonstrated the part played by complement in immune reactions—a discovery by which his German contemporaries were not slow to profit.
Wassermann and Bruck2 made experiments with complement fixation in tuberculosis before they developed the test for syphilis, and subsequently Citron3 made similar experiments. In these earlier tests, Koch's "old tuberculin" was used as