days, in sewage-polluted soil for at least 53 days, while in soil sufficiently dry to be blown about in dust for 25 days, and for about a similar period when exposed to a hot summer’s sun. The authors of this note have also proved experimentally the translation of infective material from sun-dried and dusty soil by means of wind, as also by flies which have walked over or fed on polluted earth, indicating the advisability of treating night-soil, especially from Military Cantonments, in septic tanks and filter beds before applying it to soil—_vide_ Chapter IX, page 50. [Sidenote: Area of Trenching Ground.] In order to arrive at the area necessary for a deep trenching ground for a bazaar of 10,000 inhabitants, and assuming that not more than ⅛th of a gallon of night-soil per head per diem is removed, provision will have to be made for 1,250 gallons or, say, 200 cub. ft. If the trenches are made 1 foot wide, 1 foot deep, and 1 foot apart, and are filled with 6 inches of night-soil, 400 cub. ft. will be required daily, or allowing for roads and divisions between the plots, say 12 acres, for a year’s work, or, in other words, the area required is, one acre for 833 persons. The trenches should be divided up into plots or sections for each latrine circle, excavated, when weather permits, at least a week before they are used so as to aërate the earth; the bottom of the trench should also be dug up to a depth of 9 inches for the same reason. The following extract describes somewhat forcibly what may, and undoubtedly does frequently occur in many instances:— “Trenching again is a success in dry soils, but a good deal of ground is required, and sufficient trenching ground is not always available within practically workable distances of the night-soil producing areas (public and private latrines), and often enough, whereas it may be quite successful in a given ground in the hot weather, it will, in the same ground, however fresh, prove an absolute failure in the rains, when, owing to the high water-level in the subsoil, everything trenched is brought to the surface by the gases of putrefaction, and the entire area trenched becomes a pestilential bog, crawling with maggots, bubbling with the foulest odours and swarming with blue-bottle flies, whose chief delight is to frequent the houses in the neighbourhood and infect both food and drink.” CHAPTER VIII. COLLECTION AND DISPOSAL OF REFUSE.