over and over again for years. Ashes, fine and dry, may be used, to obtain which there is the modern automatic cinder sifter. They are not considered preferable to the watercarriage system, where obtainable.

Tanks and Filters.

22226. Having obtained the source of a water-supply, a tank for a collection for a farm, or a cistern for the supply of a house, are requisite. The former may also be required to retain the rain water from the wood, lead, or zinc gutters of the buildings; water from copper gutters is poisonous. The tank is usually formed of brick or stone built in cement, and cemented inside, and when of a small size it is domed over, with a man-hole for access. If of large size, iron girders supporting slate or stone slabs will form a flat covering to it. These should be well jointed to prevent dirt falling in. Pain ing the cement with a solution of silicate of potash is said to prevent the soft rain water becoming hard in a new tank. Such a system as the following would be found very serviceable on many farms having clay lands.

2222c. In Venice, the rain water is collected from the rcofs and led into the courtyard, where it undergoes a regular system of filtration before it reaches the tank, whence it is raised by buckets. The construction to effect this consists of -I. A water-tight enclosure. II. A well of dry brick work in the centre of, III. A wall of sand, filing up the remainder of the enclosure round the well, and serving partially as a reservoir, and partially as a filter; care being taken that no water enters the well but what passes through the sand. The system is shown in the Allgemeine Bauzeitung for 1836, pl. 556; and in the Transactions of the Institute of British Architects, 1842, p. 187.

2222d. Another and more simple method is described in the Building News, 1862, p. 127. A large hole is dug about feet deep; the sides are supported by an oaken framework of a square truncated pyramid, the wide base being turned upward. A coating of compact clay, 1 foot thick, is applied on the frame with great care, to stop the progress of the roots of plants, as also to prevent the pressure of the water. A large circular stone, partly hollowed out like the bottom of a kettle, is placed therein with the cavity upwards, and on this as a foundation a cylinder of well baked bricks is constructed, having no insterstices except a number of holes in the bottom row. The large vacant space left between the sides of the pyramid and the cylinder is filled with well scoured sea sand. At the four corners of the pyramid a stone trough is placed, covered with a stone lid pierced with holes; they communicate with each other by means of a small channel made of bricks resting on the sand, and the whole is then paved over. The rain water is led from the roof to these four sink stones, and, penetrating into the sand through the channels, filters down and passes into the filter itself by the small holes left in the bottom row of bricks. These cisterns get filled about five times a year, and the distribution of water is at the rate of about 312 gallons per head.

222e The average annual rainfall is 31 inches. Where rain water has to be depended upon, parator has been invented by Roberts, which “prevents the first portion or the rainfall, ssing into the storage tank. It cants and stores the water when the roof has been washed by the first rain."

2222f. The Rivers Pollution Commissioners put the several waters derived from various sources in the following order, having regard to their hardness:-I. Rain water (softest). II. Upland surface water. III. Surface water from cultivated land. IV. Polluted river water. V. Spring water. VI. Deep well water. VII. Shallow well water (hardest). They consider water at or below six degrees of hardness to be soft, and above that number of degrees to Le hard.

2222g. are used for purifying water for towns, or purposes for which large quantities are required. They are usually formed in England of several layers of saud and gravel, gradually increasing in the volume of its particles in descending; and in the lowest course of gravel perforated tiles are laid, through which the water flows into the reservoirs. The water is supplied on the top, so as to stand at a depth of from 4 to 6 feet over the sand and other filtering media. At the Lambeth Water Works these media consist of: I. A layer of sand 3 feet thick. II. A layer of clean sea-shells 6 inches thick. III. Fine gravel 6 inches thick. IV. Coarser gravel 6 inches thick. V. Very coarse screened and washed ballast 6 inches thick; and VI. Pierced tiles covering the drains. At the Southwark Water Works the filtering media are rather thicker. At Hull the sand is 2 feet thick, and the gravel 16 inches thick. At York the sand is 4 feet thick, and the gravel 4 feet thick. At Paisley the sand is 2 feet thick, and the gravel only 6 inches; but the upper part of the sand is mixed with animal cbarcoal. Local conditions must regulate the proportion of these materials, for the thickness of the sand must be increased according to the impurity of the water. When the water is at all turbid, it is advisable to make settling reservoirs by the side of the filtering basins, to collect the impurities

in the first instance. The usual yield of filtered water from a basin established under the preceding conditions, is about 80 to 100 gallons per foot superficial per day.

2222h. Dr. Clarke's approved process for softening water is stated to be by adding an equal quantity of lime in solution to the pure lime of the bicarbonate contained in the water. The solution of lime combines with one-half of the carbonic acid and forms chalk, at the same time reducing the bicarbonate to chalk also. Chalk being insoluble, settles to the bottom. The Consumers' Economic Water Softening and Purifying Company (Limited) has been formed for the use of Atkins's patents, to adopt the recommendations of the Royal Commission on the Pollution of Rivers; and though several towns of small or moderate size had carried out those recommendations by adopting one or other of the systems then available, it was considered impracticable for any large town to do so. At the Southampton Water Works, the largest works of this sort are now (1888) completed. and many other towns are contemplating the introduction of the system.

22221. In some places both the chemical and mechanical impurities may be eliminated from water by dividing the tank by a cross wall of a filtering stone. Such a stone will filter about 60 gallons per foot superficial per day. Chemically, this could be effected by causing the water to pass through a diaphragm or cross wall, composed of two slabs of filtering stone, placed at a small distance from one another, and filled in with animal charcoal or with magnetic oxide of iron. The latter material appears to be the best for such water as is collected from roofs, because it parts with its oxygen with great rapidity to the rain water, and is susceptible of rapid revivification; it is also cheaper than onar coal. A double wall thus formed ought to pass 100 gallons per foot superficial per day. A few drops of permanganate of potash, put into water tasting and smelling of decaying organic matter, will render it in a few minutes clear and sweet. A small quantity of alum tends to render water very pure, by freeing it from matters held in suspension. Ransome's patent siliceous stone is the best material of the kind ordinarily obtainable in England. Filters of porous sandstone, as made at Halifax, are recommended as effective and durable. A paper on the subject of filtration, read at the Institute of British Architects, 1850-51, by Mr. G. R. Burnell, and given in the Builder, ix. 404, deserves attention. Household filters, whether for occasional use or for a system of domestic filtration of water as it flows from the cistern, is now often a subject of consideration for a tenant and landlord. Among these are Lipscombe's; Maignen's patent Filtre Rapide, with his patent process for softening water by means of the patent Anti-calcaire; the patent Porous Carbon Company's material; Halliday's patent high-pressure self-cleansing filter, which can be attached to the main or supply pipe; the Chamberland-Pasteur filter; Compound charcoal filter; Atkins's patent cistern filter, a pure charcoal block filter; the Queen, which can be fixed to any tap; the patent Moulded carbon block and loose charcoal thorough self-cleansing rapid water filter; the Grant revolving ball water filter, also attached to the tap on a main or service pipe, and is rapid and self-cleaning; and others.

Cistern and Supply for daily use.

.3 or more

2223. The amount of water used varies very much in different communities, but where the allowance is scanty disease of various kinds is encouraged by the absence of attention to the cleanliness of persons and of things, the want of sufficient water to flush the drains, &c. About 10 gallons a head per day are required for domestic purposes, including bathing, and about as much more for flushing purposes; the average amount required for trade purposes is generally roughly put down at an average of 20 to, gallons a head per day. Many towns have a less supply. Where there are large prhs, or malufactories requiring much water, or even a large number of animals, 3 are required. Rome had probably from about 170 gallons to 300 gallons pead per day, but authorities vary. An imperial gallon per man per day appears to be the allowance on board a vessel. In stables, each horse should be provided with 16 ga lons, four of which is consumed with his food. Each four-wheeled carriage takes about 16 gallons. Each two-wheeled carriage about 9 gallons. To wash a paved court or passage, a gallon of water may be provided for each superficial yard. The available rainfall from roofs in England is estimated at 18 inches per annum; and if the source of supply be only rainfall, a tank capable of holding 4 months' collection should be provided. (Hurst, Surveyors' Handbook.) One cube foot of cistern will hold nearly 64 gallons of water; and a cube foot of water weighs 62-321 lbs.; a gallon weighs 10 lbs. ; a cylinder inch, 02842 lbs.; and a cylinder foot, 491 lbs.; 35 cubic feet of water equal 1 ton. The supply for each man, woman, and child in a house is reckoned at 15 gallons per day, though it is considered no one really uses much more than 6 gallons, or about 12 gallons, as calculated by Sir W. Clay, by a family in London.

22234. The cistern for a house was originally placed outside, and made entirely of lead, the front of it being frequently decorated with devices, either cast with it, or secured by

paleing, i.e., the soldering on of embossed figures. Lead cisterns are still in use, but they are cased with wood, and placed were most wanted for the supply. No cistern should be put where the sun can act upon it, as vegetation in the water sometimes ensues. (1785a). 22236. A cistern is usually made of 14 or 2 inch memel fir, lined with 6 lb. lead. A cover should always be provided. This metal lining is now much superseded by one of zinc, on account of the deleterious effects arising by the action of pure water on the lead; but zinc can only be trusted as a temporary resource. Slate is a better material for all collections of water or other liquids in general use. Care must be taken that a porous quality be not supplied; and it should not be placed where mild damp air will meet it and condense on its cold surface, and so run down in drops. As it is very unyielding to the expansion of ice, its position in the house in that respect is an important consideration, and in case the joints become leaky from that or any other cause. Cisterns are supplied with water by a main service or feed pipe sufficiently large to allow of its filling during the time the water is turned on. The flow of water is regulated by a ball cock. The water supply to each bath, water closet, &c., is suggested to be controlled by a stopcock of a bore equal to the pipe. Ball cocks to be supplied with a stop cock to each, in case of repair. The cistern to have a proper standing waste for cleansing purposes only, as well as the ordinary half or three-quarter warning pipe, which must be provided, according to some water companies' rules. The fig. 615k. shows a system of water supply, where is the cistern in the roof Z, which is often placed over, but quite separated from, the water closet A. m, water pipe, cased; y, slop sink, having a tap from the main n. X, flushing tank; the cistern c, in B, also supplies the syphon flushing cistern in the servants' water closet d. The dotted line o shows the line of water pipe from the cistern c in the garden, supplying the kitchen boiler.

2223c. The cistern to supply a water closet should properly be distinct from that for domestic purposes; and when the former is placed in a confined spot, necessitating small

ness of dimensions, one of an upright form is essential to provide the head of water for flushing the basin, Fig. 806f. shows an apparatus fitted to a lead cistern for supplying water to the pan. A, the

E

D

G

B

H

Fig. 906f.

Fig. 8.7.

Fig. 807a.

ball valve pulled down by the wire B, and thus lifting, by the wire C, the valve D, which admits the water into the lead service-box E, soldered into the bottom, F, of the cistern. The air-pipe G lets out the air from the box forced into it by the pressure of the water rushing through the down pipe H. A waste pipe for emptying the cistern, or for carrying off the surplus water when being over filled, must always be provided. When a cistern supplies the house, a service pipe is required from it, the outlet having a rose. For a slate cistern, a brass flange (fig. 807.), fitted with screws and nuts, is soldered to the lead service-box, and then secured to the slate. A "round closet valve with union, fly-nut," and air-pipe (fig. 807a.) is occasionally used in lieu of the above contrivances; or a spindle valve with union, fly-nut and air-pipe.

2223d. Iron tanks and cisterns made of plate iron riveted, plain or galvanized, are formed to any shape or size; as also of a small size in stoneware. A question has arisen as to zine and zinc-coated iron for cisterns. Soft water, such as rain water, dissolves zinc more easily than hard water. Water containing carbonic acid is specially able to dissolve it. The French Government have prohibited the use of galvanized iron tanks on board men-of-war. Professor Heaton analysed spring water, with a further analysis after it had passed through half a mile of galvanized iron pipe, and found it had taken up 6 41 grains of zinc carbonate per gallon. Dr. Venable states that where spring water passed through 200 yards of such pipes it took up 4 29 grains of zinc carbonate per gallon (John Smeaton). To stop leaks in iron cisterus, mix litharge and red lead; if to dry quickly, gold size mixed with boiled linseed oil. Extra hard carriage varnish is useful for inside purposes only, well rubbed into the crack.

2223e. With the constant supply system, now being generally introduced, service cisterns are said to be unnecessary; but it will be advisable to have one, and especially near

any office requiring a good supply of water, as the service is occasionally cut off for two or three days during repairs or cleaning of the mains. Some lower-class houses are said to have a 6-inch zinc-lined trough instead of the usual cistern; hence frequent stoppage of drains occur from want of flushing power, as depth of water is essential for it.

Water-waste Preventer.

2223f. In some towns the water company insists upon a small cistern being placed in the water closet, or to a urinal, to prevent waste of water, as it is stated. There are various patents, worked by a syphon or other action. They are each regulated for a supply or flush of about a couple of gallons of water at a time. Such are Purnell's syphon; Winn's Acme; the Peckham (No. 2) improved pneumatic syphon cistern for fixing in a cistern, has no valves, rubbers, washers, &c., the action is noiseless, and the connection is by an air pipe of inch bore, worked by a push knob; the Invicta; the Peerless; the Suphon; the Double valve; the York; Trott's patent; Crapper's syphon; Bolding and Son's syphon, their Simplex after-flush, which is not syphon action, is a simple apparatus; the registered double syphon; Tylor and Sons' improved patent model waste-not cistern valve, for fixing in a cistern under water; Smeaton's new water-waste preventing valve; Humpherson's syphon cistern; Bean's direct-acting valveless cistern; Bostell's cistern. Most of the patents are noisy in action, and all are of questionable utility for the purpose, often getting out of order and wasting water rather than preserving it, besides preventing that useful flush of water which aids in keeping the drains clear.

Pipes.

2223g. The pipes used for the purposes of building are proportioned to their uses. Those, for instance, called soil pipes, for carrying away the soil from a water closet, or those for conveying water from roofs, called rain-water pipes, and those occasionally from sinks, are, of course, of larger diameter than those called service pipes, which are merely, as their name implies, for laying on water to a house, those of somewhat larger diameter being called main service or supply pipes: the service pass from the mains to the cistern.

2223h. From the cisterns pipes are required to convey the water to the several places it is destined to supply. Those of lead are either cast round or soldered. In casting, a mould is made of brass, wherein down the middle a core of iron is loosely supported, at such a distance from the mould all round as is equal to the contemplated thickness of the pipe. When this is set the core is removed, and the cylinder opened so as to withdraw the pipe, which is much thicker than is needed, and must be lengthened, while its substance is reduced, by drawing it through a succession of holes in steel plates, diminishing gradually in diameter, similarly to the method employed in drawing iron rods. This machinery became gradually improved in its construction, so that it was of rare occurrence to meet with an imperfect pipe. Lately the manufacture of lead pipes has been further improved by casting them under hydraulic power. A quantity of lead is placed in a box, and forced through the mould at a certain rate, which gives the metal time to cool, so that it is pressed out gradually in a complete state, and wound round a wheel ready for use, its length being made within the limits of carriage. When pipes are made by soldering, a core of wood is provided, round which the sheet lead is rolled, and the elges are brought together and joined with solder. A solid drawn lead pipe with a distinct inside lining of block tin th of an inch thick was made, but it was found expensive, and the labour involved in fixing it prevented its ready adoption; also a solid drawn square or rectangular fall pipe; both by Hanson, Dale & Co., of Huddersfield. Hellyer has made a square drawn lead pipe for outside of houses. Glass lined pipes are later. Glass pipes for conveying distilled water are used in laboratories.

22231. Concussion in water pipes is caused by the weight of water being shut off and stopped in its flow while turning off the end tap suddenly. If it be turned slowly this does not take place. The noise may be obviated by continuing the pipe (or a smaller one) over the tap, and inserting the end into the pipe. Either the water rebounds into the supply or the curved piece of pipe contains air, which serves as a buffer. The same arrangement answers for gas pipes where the last jet sometimes has a quivering flame; or the pipe (in either case) can be carried into another pipe near to it, so as to obtain a circuit.

Soil Pipes.

2223k. The most important point in connection with the water closet is the soil pipe. Great care is necessary in fixing it. It should be hung on tacks of lead at least one pound heavier than that from which the pipe is made, at least nine inches long, to take three courses of bricks, and three tacks to each ten feet length of soil

Its trap

Pipes from slop

SINK

pipe. Often in the course of three or four years the soil pipes start crawling down, owing to the fixings being scamped. It should not be nailed too closely. sinks are often branched into the soil pipe, and require the same treatment, also care to prevent syphonage, should be as close to the fixture as possible, so as to avoid a length of pipe, which might become foul on the near side of the trap, and so become a nuisance of itself. Bauner's soil pipe traps are either for the soil pipe at the end, or the soil pipe in the centre, each trap having a fresh air or rain-water pipe inlet, and an inspection hole. Doulton and Co. manufacture vertical soil pipes, or patent safety house drainage pipes,

8

A

A

B

B

MAIN SEWER

SIPHON

Fig. 8076.

being incorrodible, with junction pieces, fastened to the walls by ornamental iron bands, readily adapting themselves to any settlement of the brickwork; and are made in lengths of 3 feet, and of 4 in. and 6 in. diameter.

22231. The wastes from a bath, a lavatory, a pantry, or a wash-up sink (as partly shown in fig. 807b.), require special treatment. The discharge from a sink should be under the grating of an intercepting trap, not upon it, as is sometimes done. Under the fixture, and as near to it as possible, should be a syphon trap of good construction, soldered, if to a siuk, with only a taper piece to take its grating or washer. The waste from a bath, &c., is sometimes carried through the wall into the open hear of a rain-water pipe, or other contrivance, and so to a grating the end being left open; a syrhon trap under the fixture is useful, though not often put A 2 or 2 inch lead pipe may not be found too large. Safes are provided under the old water closet apparatus, and under a bath, for which 4 lb. lead is enough. The waste pipes from these should also be carried outside, the end provided with a mica or brass flap valve to prevent an in-draught.

2223m. The fresh air inlet pipe is considered by many as preferable if kept smaller than the ventilating pipe. The soil pipe, if it have considerable fall, must have a provision made for the partial vacuum which the column of water in descending tends to create causing syphonage of the Fig. 807c. traps. This pipe being open at the top is not sufficient to remedy the evil; a separate vertical ventilating pipe is the only effectual remedy, into which, from all the horizontal branches, are secured ventilating branches. This vertical pipe may be about 3 inches in diameter, with 2 inch or 24 inch branches at least, carried from the soil pipe into the other vertical pipe. The fig. 807c. shows how the trap under a water closet may be ventilated, where closets are placed one above another to prevent syphon ge. A is the soil pipe; B the ventilating pipe, or ventilating pipe from the grease or other trap; and P, ventilating pipe from branch pipe to soil pipe. The separate air shaft to the trap might perhaps be better dispensed with by carrying the small pipe through the wall to the open air, and using a mica valve; thus fresh air would be constantly brought in. Mica valves are considered by some to decay. (E. T. Hall.)

2223n. Solder is a mixture of two parts of lead with one part of tin. In soldering, portions of the lead must first be scraped, and when finished they are then done over with a black paint. This solder is used also for tin plates and zine work. There is a new process for connecting lead pipes without solder, called a cold metal double cone mechanical lead pipe joint. By means of a small piece of a double coned full-bore tube, assisted by a tubular hexagonal-headed screw and nut, the joint is firmly and securely made, and easily taken apart when required. A new system of jointing, which is readily applicable to every kind of joint required for lead pipes, is adopted at Manchester, whereby the joints are not merely soldered, but welded. A lining pipe is used somewhat similar to the above mentioned process. A clean bore is obtained, no lodgment of solder inside, and a sightly external finish instead of the ugly bulb by the common method. Stidder patents à closet arm joint with india-rubber cones.