Crude cephalin as the active substance of organ extracts able to convert venous blood into hemostatic blood

The effect on hemostasis of organ extract mixed with venous blood was studied in the dog's hind leg preparation. According to the methods of extraction employed and the properties described, the active substance of tested extracts able to change venous blood into hemostatic blood is similar to crude cephalin. Crude cephalin is active in concentration of 10 mg./100 ml. of venous blood. These observations show that cephalin, besides its effects on coagulation, has a direct activity on hemostasis of incoagulable and previously nonhemostatic venous blood.