A preliminary report of a new gelatin liquefaction method.

This method depends upon the use of formalindenatured gelatin with finely powdered charcoal incorporated as an indicator of liquefaction. The gelatin charcoal is used only as a substrate for testing the gelatinase activity and not as a nutrient medium. This substrate contains a large number of minute particles of charcoal with a comparatively small amount of gelatin as binding substance. Consequently even small quantities of liquefied gelatin will release appreciable numbers of easily recognized charcoal particles.