We have made a brief editorial notice1 of some of the results obtained by von Behring and his coadjutors in their investigations of tuberculosis. The opinion was expressed then that some of the fundamental problems in tuberculosis were approaching solution, more particularly the problems in immunity to tuberculosis. Behring has succeeded in demonstrating that by injecting cattle, especially young, with small quantities of cultures of tubercle bacilli isolated from human tuberculous lesions, there is produced a complete immunity to bovine tuberculosis so far as may be determined by ordinary experimentation. He designated this method of immunization as "jennerization." It resembles in the essential points the method elaborated by the immortal Pasteur of immunization by "vaccinati[ill] with attenuated virus.
Now the fact that cultures of human bacilli produce such solid immunity to virulent bovine bacilli can not be interpreted otherwise than as indicative of the close relationship between the tubercle