The amount of fat capable of being retrieved in this manner is certainly startling. The fat-trap which I saw fitted to one of the sinks of an army cook-house yielded several pounds of fat every day--sheer waste recovered from washing plates, pots and pans. The fat is dispatched to the swill-mill to be passed through the melter and extractor in the usual manner, thereby undergoing thorough clarification and sterilization. The recovery during the course of the year of several thousand pounds of fat which otherwise would have vanished down the drain, by the introduction of a small wooden box such as I have described, represents no mean achievement. Certainly it serves to bring home the losses which are incurred at this point in every house during the twelve months. The device might profitably be installed at every sink by every householder. The few shillings involved by its provision would be quickly recouped, because the fat always has a market. Moreover, the introduction of this device would contribute towards the efficiency of the drain, keeping it clear and free to fulfil its designed function. That it pays to recover all fats and greases lost to consumption or permitted to escape because it is merely residue is conclusively borne out by the results recorded in connection with the military operations which I have described. During the year 1917 the fats--waste--reclaimed from the Home Commands of the British Army yielded 13,000 tons of tallow. The value of all the by-products recovered from the refuse was £700,000--$3,500,000. The cost of securing this waste for commercial exploitation, including the extra pay extended in the form of bonus to the cooks, and other allowances, was £400,000--$2,000,000--leaving a balance of £300,000--$1,500,000--which was returned to the public. As previously mentioned, the fats were urgently needed to furnish glycerine for the manufacture of munitions. One ton of crude fat yields 10 per cent. of glycerine, so that 1,300 tons of this indispensable article were derived from this one source of supply. The fat was sold to the bone-degreasers and the soap manufacturers, who effected the recovery of the glycerine, selling the product to the Ministry of Munitions at the agreed price of £59 10s. to £63--$297.50 to $315--per ton, as compared with £300--$1,500--per ton which we should have been compelled to pay had we bought the glycerine upon the open market.