So far as the initial plants were concerned dependence had to be placed upon existing structures, otherwise delay in putting the scheme into practical application would have been inevitable, owing to the difficulty attending the acquisition of constructional material. But the installation of the plants in extemporized buildings sufficed to establish the applicability of the idea to any type of building of adequate dimensions, and in such a manner as to impose only the minimum of structural alterations to secure the requisite efficiency. This adaptability is an outstanding feature, because it indicates how the recovery of organic waste may be attacked along the most economical yet comprehensive lines, and with the minimum of capital expenditure and its concomitant amortization charges. Two types of plant were adopted, both being standardized. One coincided with what might be described as the central or permanent waste-recovery station, while the second presented all the necessary elements of portability with the added advantages of inexpensive dismantling, removal, and expeditious reassembling at another point according to exigencies. But the processes are common to both types. In the case of the permanent mill which I visited structural alterations had been reduced to the absolute minimum, the most conspicuous outlay being the provision of a simple form of elevator to lift the swill to a level above the plant to permit of gravity feed. The total cost of this station, including the installation of the necessary machinery, which included a steam-boiler, bone-crusher, small engine, melter, centrifugal or turbine fat extractor, and settling tanks, with one or two further accessories, was only £2,500--$12,500. The swill is brought to the mill by motor-lorry. Operations are commenced at an early hour, because health considerations demand that waste of this character shall be handled with all possible promptitude in a big camp. The clearance is carried out daily and is complete, including all garbage, bones and other profit-yielding organic residue from the cook-house. Segregation is conducted as far as practicable at the source, special sanitary vessels for distinctive residues being provided. The mill continues working throughout the day until the whole of the morning’s collection has been duly treated. No accumulation or carrying-over of some of one day’s swill to the next day is permitted. Swill is susceptible to speedy fermentation, especially during hot and sultry weather, and so would become noisome within a very short period, as well as developing into an ideal breeding-ground for flies and other pests.