At this juncture the attention of the Corporation was attracted to Dr. Grossmann’s process. It was investigated and submitted to searching experiments spread over a period of three years at the sewage works. From the results obtained and the experience gathered, it gave promise of being completely successful when conducted upon a large scale. So it was adopted. The Grossmann process may be said to represent the most logical exploitation of sewage yet attempted in accordance with the severe hygienic conditions imposed to-day. Curiously enough, when the disposal of sewage by water-carriage was first introduced, the critics of the principle did not hesitate to point out that it represented the most wasteful solution of the problem which had ever been accepted for practice. But against these contentions the advocates of the idea urged that the hygienic advantages to be gained were so overwhelming that the question should not be considered from the commercial view-point at all. Other days, other manners. In this instance, however, not many years passed before the issue attracted such widespread attention as to demand searching investigation, the difficulty and cost attending the disposal of the sludge being responsible for a pronounced outcry against the method. The sludge problem was thoroughly probed by a Royal Commission, by which the opinion was expressed that the value of this waste, calculated upon the volume of dry substance contained therein, was no more than 10s.--$2.50--per ton at the very outside. But as the sludge is produced in a form showing a high percentage of water it was hopeless to expect farmers to absorb it, owing to the transport charges involved for such a comparatively low manurial return, unless their land happened to be situate close to the centres of production. To overcome the water difficulty attempts were made to dry the sludge, in the effort to reduce its bulk, but it was discovered that drying did not constitute a complete sterilization process, with the result that the material was liable to carry infection. But the greatest objection to drying is that this very process, while it achieves one end--the transport difficulty--provokes another disability. The sewage is worth less after drying than in the saturated form. The presence of fat in material quantities has always been responsible for agricultural hostility towards this waste as a fertilizer. The fat is due to soap used in the household, and which is thrown down the drains, as well as the grease resulting from other domestic operations. The great objection to grease is that it has the tendency to clog the soil.