SANITARY SCIENCE. 



719 



Cess-pools under houses, forming reservoirs 

 of foul gases that can have no outlet except 

 into the dwellings. 



Foul water-closets in cellars, contributing 

 their impurities to the furnace and household 

 air-supply. 



Refrigerator waste-pipes running direct to 

 the sewer and poisoning the food, especially 

 the milk. 



Old lead soil-pipes corroded by gases or 

 gnawed by rats, so as to be in a dangerous 

 state. 



Cast-iron soil-pipes full of sand-holes, which 

 are neither gas- nor water-tight, with joints 

 made of putty or cement, which permit the 

 escape of foul air. 



Basins and other fixtures without traps of 

 any kind, or with traps of unsuitable shape or 

 size, which readily siphon by their own dis- 

 charge or that of some other adjacent fixture. 



Soil - pipes without ventilation, breeding- 

 places for gases, which from the absence of 

 any trap on the main drain readily enter from 

 the street-sewer or cess-pool. 



Water-supply tanks or cisterns with over- 

 flow-pipes connecting with the sewer or with 

 drains, and thus polluting their contents. 



Pan water-closets, outwardly clean to the 

 eye, but foul and filthy within, creating offen- 

 sive odors, which commonly have a direct vent 

 through the waste-pipes of adjoining baths and 

 basins, while from the shortness of the water- 

 supply they have insufficient flushing. 



Materials. The materials used by plumbers 

 include lead, iron, brass, copper, zinc, tin, silver, 

 earthenware, marble, and slate. Lead was for- 

 merly the principal material, but it has since 

 been largely superseded by other ingredients. 

 Tin, iron, shingles, and asphalt have replaced 

 le.id almost entirely for roofs, the construction 

 of which was formerly the main occupation of 

 plumbers, while iron, brass, and various com- 

 position-pipes have diminished the proportion 

 of lead pipe used for carrying water. Again, 

 iron soil-pipe has entirely superseded lead 

 pipe in this country, and copper-lined and iron 

 tanks are being substituted for lead-lined tanks. 

 Under the head of plumbers' ironware may be 

 mentioned soil- and drain-pipe, hopper water- 

 closets, bath-tubs, sinks, tanks, and the cheaper 

 grades of urinals and wash-basins. Brass is 

 employed for faucets and various styles of 

 stop-cocks and couplings, valves, plugs, etc. 

 Copper is employed for lining tanks and boil- 

 ers, and for water- closet pans, bath-tubs, sinks, 

 bath-showers, and floats for tanks. Earthen- 

 ware is largely replacing metal, especially for 

 basins, urinals, water-closet bowls, wash-trays, 

 sinks, and baths. Wood, which was once used 

 for cisterns, bath-tubs, pumps, and water-mains, 

 is now employed only for casing fixtures or for 

 the outside of cisterns. Among other mate- 

 rials are slate, particularly for urinals, soap- 

 stone for wash-tubs, plate-glass for the sur- 

 roundings of sinks and urinals, nickel used in 

 plating pipes, and silver for plating faucets. 



The earliest water-pipes were made of 

 earthenware, or logs of wood; but, as they 

 could not sustain much pressure, lead was em- 

 ployed, both for conveying water from aque- 

 ducts to houses and for the mains also. In 

 Rome some street-mains were eight inches or 

 more in diameter. These pipes were not cir- 

 cular, but usually pear-shaped, nnd were made 

 by bending sheet -lead, usually in ten-foot 

 lengths, so as to bring the edges together, and 

 soldering them ; sometimes with the addition 

 of a plain strip of lead or a cap, to make a 

 tight joint. It does not appear that the an- 

 cients understood how to join lead by burning. 

 Their sheet-lead was very thick, and specimens 

 that have been preserved show no signs of 

 wear. Cast-lead pipes were also used by the 

 ancients, and were circular in section. They 

 usually had the name of the reigning emperor 

 cast upon them if for public use, while those 

 found in private dwellings bore the manufact- 

 urer's name, or the name of the house-owner. 

 The quantity of lead used by the Romans for 

 plumbing was enormous, as may be inferred 

 from the statement that 13,594 one-inch lead 

 service-pipes drew water from a single aque- 

 duct. Not only were pipes and tanks made of 

 lead, but it was employed for pump-barrels, 

 cocks, and everything connected with their 

 water-supply, except the large shut-off bronze 

 valves in the street-mains. Archimedes, 2,100 

 years ago, used lead pipes to distribute water 

 on board a large vessel that he built for Hi- 

 ero, King of Syracuse, the water being forced 

 through the pipes by means of pumps. Lead 

 plates, cast in sand, have been used for many 

 thousand years, both for roofing and for re- 

 taining earth and water in the hanging gardens 

 of Babylon and other great cities of the East. 

 In Oriental countries the practice of using lead 

 for roofing still continues. 



Traps. There are many kinds of traps, good 

 and bad. The majority are too small and 

 placed too low, so as to leave a foot or two ot 

 pipe between them and the basin or other fixt- 

 ure, which becomes coated with slime. Many 

 other traps are of bad form, and either siphon 

 themselves when discharged or are siphoned 

 when an adjoining fixture is emptied. The or- 

 dinary S-trap is as good as any, but even this 

 should be ventilated. The different forms of D- 

 traps are merely small cess-pools, and accumu- 

 late foulness. Large traps are always objection- 

 able, as they are never looked after or cleaned 

 out. If householders would abandon their 

 illusions on the subject of traps, and pay more 

 heed to the defects of the ordinary foul pan 

 water-closet, they would be aiming in the 

 right direction. 



Snpply-Pipes. According to Prof. W. Ripley 

 Nichols, who has given special attention to the 

 effect of water on different kinds of metals, 

 the use of lead service-pipes for the household, 

 while generally unobjectionable in places fur- 

 nished with a public supply, should be avoided 

 where the water is drawn from a well. The 



