Plumbing 227 



way or the other as to the absolute effectiveness of the non-syphoning trap, and 

 choose accordingly. As it is still, unfortunately, an open question, this is the best 

 advice we can give. 



The rough piping is of wrought or cast iron, as the case may require, and 

 galvanised or painted for its protection. Lead is still used to some extent for 

 small pipes, but its expense is an item to be considered. Exposed pipes both for 

 waste and supply should be of nickelled brass, as is all other exposed metal work. 



The sizes of pipes are usually as follows: Main and branch soil pipes, 4 

 inches; main waste pipe, 2 to 3 inches; branch waste pipes for washtubs and kitchen 

 sink, 2 inches; for other fixtures, i| inches; main vent pipes, long branch vent 

 pipes and branch vents for fixtures with traps larger than 2 inches, 2 inches; branch 

 vents for fixtures with traps 2 inches or less, i^ inches. The inside dimension of 

 the outside sewer pipes should be 6 inches. 



It is best not to seal up any pipe in a partition or flooring; there should be 

 some way of getting at it in case of necessity. It may be by means of wall panel, 

 false pilaster or beam or floor trap, but it should exist. 



Having completed the system up to the point of connection with fixtures and 

 sewer, it is necessary to test it, to prove to one's satisfaction that no flaws exist. 

 This should be done by the "water test." To effect this, all openings but the top 

 of the soil pipe at the rtfof should be closed with patent pipe closers and the system 

 filled with water to the top; the detection of leaks is then an easy matter, and 

 such should be carefully repaired and again tested; repairs and tests should con- 

 tinue until absolutely tight. 



When the system is complete and ready for final acceptance it should 

 undergo another test, the "peppermint test." Essence of peppermint having been 

 mixed with a pail of water, the mixture is poured down through the soil and vent 

 mains from the roof, using a bucketful for each main. Someone who has not 

 been near the peppermint or its mixing should then go carefully over the entire 

 system to detect any odour which may leak through after the application. If 

 repairs have to be made the test should be repeated after each attempt at rectifica- 

 tion. A satisfactory tour should detect no odour, hence the work, as far as its 

 tightness is concerned, should be accepted. Under no circumstance should the 

 peppermint be brought into the house, as it will permeate everything and render 

 its usefulness void. Care in this direction may save much trouble and loss of time. 



House at Merion, Pa. Gothic design in random, quarry-faced 

 ashlar. Wm. L. Price, architect 



