While the dry vacuum process is certainly efficient, it does not fully comply with the latest ideas pertaining to the recovery of fats from organic waste. The press is the weak link, because thereby it is only possible to recover a certain proportion of the fat held up in the mass, even when the cellular construction has been completely broken up. It is stated, as a result of accumulated experience, that the amount of fat left in the greaves may run up to as high as 10 per cent. of the original fatty content of the offal: in many instances it has been found to range as high as 20 per cent. The fact that this remaining fat defying reclamation by pressing must be relatively high is evident from the readiness with which certain waste exploiters will buy up the greaves, not to turn them into kennel and poultry foods, but to submit them to further treatment in order to wring out still more of the fat which they carry. This manifestation of enterprise has been rendered possible by the advance of the science of fat recovery from offal to such a level as to enable 9 per cent. of the fat remaining in a 10 per cent. greaves to be extracted. It is the prevailing high price commanded by fats which renders such additional treatment upon an extensive scale so attractive and eminently profitable. The process in question is the Scott solvent recovery invention to which I have referred, and which represents the greatest achievement yet recorded in the whole science of fat reclamation from organic waste. The process was perfected and patented shortly before the war, and although hostilities militated against its immediate and rapid development, thereby delaying the recognition of its overwhelming virtues, it is satisfactory to learn that many plants operating upon this principle have been laid down, not only in this country, but in other parts of the world. It is the process which at the moment is arousing the most intense interest, owing to the progressive stride which it represents in this field. The process is delightfully simple, although apparently it involves an intricate plant and demands a higher level of skilled labour, but where the work of reclamation is conducted along ambitious lines it cannot be excelled. Briefly described, it turns upon the employment of benzine, or some other equally volatile solvent which, as we all know, will readily dissolve fat and absorb it. What can be done with this agent is familiar to every housewife who practises the removal of grease spots and other unsightly marks from clothing by the aid of benzine, while it is the medium whereby dry-cleaning is rendered practicable.