Withy. — On Sanitation and Ventilation. 467 



tion-saddle should be procured and cemented to the drain in 

 these cases, great care being taken in making the hole. 



Intercep ting -trap. 

 Having laid the house-drain properly, the next thing is to 

 choose an intercepting-trap through which the soil-pipe may 

 enter it. Plate XLVIIL, fig. 1, shows such a fitting. Pro- 

 bably the best material for this is glazed earthenware, because, 

 being of the same material as the drain, a perfectly tight 

 cement joint can be made. This trap serves the double pur- 

 pose of preventing air from the drain entering the soil-pipe, 

 and at the same time of providing a fresh-air inlet to the 

 latter. It must be placed outside of the house in every case, 

 so that an efficient air-inlet can be provided direct to it. In 

 addition to the air-vent and inlet, this fitting must embody 

 two other features, viz. : (1) A sufficient water-seal, and (2) a 

 good drop from the entering-pipe to the surface of the water 

 lying in the trap. 



Soil-pipe Ventilator. 



The trap just described provides for the admission of fresh 

 air at the foot of the soil-pipe. This must be supplemented 

 by an outlet above the windows, and, if possible, above the ridge 

 of the roof. When so constructed the air will be able to pass 

 through the whole length of the pipe, and thus to prevent any 

 accumulation of injurious or even offensive air. It will be an 

 improvement to put a good extracting ventilator upon the top 

 to increase the air-current. Of the two methods of providing 

 an outlet on the roof I prefer that which is shown in Plate 

 XLIX., fig. 1. It consists in carrying up a 2in. galvanised-iron 

 pipe, with soldered joints, inside the house, from the outside 

 of the trap under the water-closet. If there is a second closet 

 its ventilating-pipe can be branched into the main one. A 

 thorough test of the tightness of these pipes should be made 

 by filling them with water. 



Water-closet. 



There are many styles of water-closets ; but I think that 

 none of them can compare with the modern ones which are 

 made entirely in one piece of glazed earthenware. Any valves 

 or movable pans are objectionable, from the certainty of their 

 fouling, and from their liability to leakage either from that 

 cause or from getting strained. The old pan-closet with the 

 capacious trunk under it is simply an abomination, without a 

 single redeeming feature. It has been wisely condemned at 

 Home by the Local Government Board. There are two other, 

 and more modern, valve closets which were designed to avoid 

 some of the objections to the old one, but they do so very im- 



