Donaldson’s Separation Latrine, in which the urine and solid matter are kept separate, is also an excellent pattern. Separation latrines are, however, unsuitable where it is proposed to deal with the night-soil by bacteriological agency, and must seriously decrease its manurial value also. It is merely a handy way of disposing of solid fæces. [Sidenote: Alipore Pattern Latrine.] The Alipore pattern latrine is a good type. Stoneware seats set in brick-work are preferable to iron ones. Septic tank latrines are very useful under suitable circumstances. A design for a 12–seated one with a separate flushing tank for each seat is shown in Fig. 13, page 28, the estimated cost being Rs. 4,586, or Rs. 382 per seat. Before deciding on adopting a latrine of this description, “Sewage Disposal in the Tropics,” by Major Clemesha, I.M.S., Sanitary Commissioner, Bengal, should be consulted. [Illustration: BAILEY’S PATENT LATRINES, WITH SUPERSTRUCTURE “STANDARD PATTERN.” FIG. 12. ] [Illustration: PLAN OF 12 SEATED SEPTIC TANK LATRINE LONGITUDINAL SECTION PLAN FIG. 13. ] [Sidenote: Masonry Latrines.] [Sidenote: Disadvantages of Tarring.] Where masonry latrines or urinals are provided, the walls and floor should be smooth and well polished to allow of easy cleaning, and should be white or some light colour, so that if there is dirt, it can be at once seen and removed. In latrines for hospitals, and also in public ones which are much frequented, it would be an advantage to line the walls to a height of 3 feet, and also the floors, with glazed tiles or bricks. This will make them much cleaner and less forbidding looking. It is an obvious mistake to coat the lower part of a latrine wall with tar, the antiseptic value of which, especially in a hot climate, is soon lost, and which hides and retains dirt in its composition. The usual practice is to cover a dirty latrine wall with a fresh layer of tar, thus preserving an old coat of filth and forming a fresh bed for a new one. In all latrines it is of great importance to have the rear openings of convenient size for the efficient removal of the buckets from their seats on the level platform. [Sidenote: Urinals.] A cart urinal in the vicinity of cutcherries will be found useful. This is merely a receptacle of convenient size resting on a masonry floor and placed under a raised and enclosed platform on which the squatting plate is fixed; the receptacle can be easily removed and replaced by an empty one; the form is a convenient one and can be efficiently ventilated. [Sidenote: Hindu Patent Urinal.] [Sidenote: Disinfectants.]