Fresh feces are ground in a mortar to uniform consistency. A 2-3 g. sample is thoroughly mixed with 2 ml. concn. HC1, 20 g. of plaster of paris are added and the whole ground together and left for 30 min. Mixture is then reground and extracted with dry light petroleum for 3 hrs. The solvent is driven off on a water bath, a current of air is played over the surface for 2 min. to remove any extracted HC1 and then the fat is dried in a steam oven and weighed to give total fat. Split fat is detd. by dissolving in 30 ml. of benzene and titrating with 0.1 [image] Na-ethoxide in ethanol to phenolphthalein. Neutral fat is obtained by difference.