During the last seven or eight years, many clinicians have been treating arthritic patients by means of intravenous injections of foreign protein. These produce chills which resemble malarial paroxysms and afford an ideal opportunity for studying in man the phenomena of temperature regulation. In 1917 the chills and fever in several cases of malaria were studied in the Sage calorimeter.1The present investigation was undertaken as a supplement to the work in malaria in order to study in more detail the mechanism of the rise and fall of body temperature. The gaseous exchanges of patients have been studied by Kraus and Chvostek2after giving tuberculin, and in animals by Freund and Grafe,3Versar, who gave infusions of sodium chlorid,4and by Berrar,5who used aloin. In general, these animal experiments showed a rise in total oxidative processes accompanying the rise in temperature. Sometimes this increase amounted to 130 per Tie