The favorable effects of fever on certain types of psychoses was known to Hippocrates and Galen, but it seems that Rosenblum,1in 1875, was the first to inoculate purposely patients suffering from psychoses with febrile producing organisms. As early as 1854, Jacobi2reported on the use of artificial abscesses in the treatment of general paralysis. In 1887, Wagner von Jauregg3published a collected review of the influence of such diseases as cholera, typhoid, erysipelas and relapsing fever on psychoses, and proposed that one should intentionally imitate these experiments of nature for the cure of psychoses. This suggestion was realized by von Jauregg4when, in the summer of 1917, he inoculated patients suffering from general paralysis withPlasmodium vivax, which he obtained from the blood of a soldier ill with malaria fever. Previous to this, von Jauregg and Pilcz5treated general paralytic patients with Koch's old