THE present shortage of fats, especially butter, gives a particular interest to two papers published by the Society of Chemical Industry. The first, printed in the Journal for October 31 last, is by Dr. A. Lauder and Mr. T. W. Fagan, who experimented on the utilisation of fatty acids for feeding purposes. The large increase in glycerol manufacture for explosives has resulted in the production of a quantity of fatty acids much in excess of what can ordinarily be utilised. According to the view now held of the digestion of fat in the animal organism, there does not seem to be any physiological reason why it should not assimilate free fatty acids. In the authors' experiments ten young pigs (about seven weeks old) were fed, the first five on a mixture of maize meal and sharps, the remaining five on a smaller ration of the meal and sharps mixture, together with a small quantity of the fatty acids from coconut oil. About 5 oz. of the fatty acids replaced 1 lb. of the meals. In addition to the above rations, a certain quantity of cabbage was given to the pigs. The results showed that the increases in the live weights of the two lots of pigs when the experiment had lasted for seven weeks were practically identical. The conclusion is drawn that the fatty acids were assimilated, and that they replaced about two and a half times their weight of carbohydrate.