A more competent person could hardly have been selected. In 1871, in his inaugural address as professor at the University of Vienna, Lang advanced the view that the syphilitic contagium must he ¡i living organism, having the Eaculty of multiplying in healthy "idividuals, a view which he still maintains and explains thereby the pathological phenomena manifested by the disease process. At, the same time, he distinctly recognizes that we have not yet acquired a clear knowledge of the character of

more »

... he syphilitic collegium. Lang holds that persons who have once had constitutional syphilis are rarely susceptible to a new 'nfection, but there is no absolute immunity, and he slal|,s that he has almost every year occasion to observe cases of reinfection. He considers that clinical and experimenta] researches make it absolutely cer-