Page:Encyclopædia Britannica, Ninth Edition, v. 4.djvu/564

Rh 502 BUILDING PLUMBER-WORK. Tools. of England, is the truss after the ears have been cut off, leaving the clean, sound pipe straw, of which a thickness of 3 inches is laid on the common thatching with spars only. The materials required are straw or reeds, laths, nails, withes, and rods. A load of straw, laid on about 12 to 1C inches in thickness, will do a square and a half; a bundle of oak laths, !- inches wide, and from -j- to fths thick, nailed about 8 inches apart, 1 square ; a hundred of withes, 3 squares ; a pound of rope yarn, 1 square ; a hundred of rods, 3 squares; and 2 hundred of nails, 1 square. Probably thatched roofs were formerly orna mented by a species of cresting, for in some parts of the country the withes or willow twigs that bind the thatch are sometimes arranged on the tops of ricks and cottages in an interlacing manner, terminating at the apex or at each end with a spike with a rudely formed cock. Viollet-le- Duc, in his Dictionnaire, alludes to the custom of forming the ridge in mud, in which plants and grasses were inserted to prevent the earth being dissolved and washed away by the rain. PLUMBER-WORK Lead, as the name imports, is the material in and with which the plumber works. The principal operations of this trade are directed to the covering of roofs and flats, laying gutters, covering hips, ridges, and valleys, fixing water trunks, making cisterns and reservoirs, and laying on the requi site pipes and cocks to them, fixing water-closet apparatus, setting up pumps, and applying indeed all the hydraulic machinery required in economic building. The plumber s tools are knives, chisels, and gouges for cutting and trim ming, rasps or files and planes for fitting and jointing, a dressing and flatting tool for the purposes its name expresses, iron hammers and wooden mallets for driving and fixing, ladles in which to melt solder, grozing irons to assist in soldering, a hand-grate or stove which may be conveniently moved from place to place for melting solder and heating the grozing irons, a stock and bits for boring holes, and a rule of two feet in length divided into three parts, two of boxwood, the third of steel, for passing into places he may have to examine; also compasses, lines, and chalk for setting out and marking, and centre -bits of all sizes for making perforations, together with weighing apparatus, as the quan tities of most of the materials used by the plumber must be either proved or determined by weight. The waste of lead in working is very trifling, as cuttings all go to the melting pot again with little or no loss but that of refouud- ing or casting ; and even old lead is taken by the lead merchant in exchange for new at a very trifling allow ance for tare and the cost of reworking. A plumber is always attended by a labourer, who does the more labori ous work of carrying the materials from place to place, helps to move them when necessary, melts the solder and heats the grozing irons, attends to hold the one or the other, as neither may be set down or put out of hand when in use, and assists in some of the minor and coarser operations. Action of In boarding roofs, flats, and gutters for lead, clasp-nails iron on or flooring brads should be used ; and the first care of the plumber should be to punch them all in from an eighth to a quarter of an inch below the surface, and stop the holes carefully and completely with putty, or a chemical process will ensue on the slightest access of moisture should the iron heads of the nails come in contact with the lead, and the latter will, in the course of no long period, be completely Use of perforated over every one of them. Neither should lead in surfaces of any extent be soldered, or in any manner fastened at the edges, without being turned up so as to make sufficient allowance for the expansion and contraction which it is constantly undergoing during the various changes lead. solder. in the temperature of the atmosphere. It may be taken, indeed, as a general rule, that solder should be dispensed with as much as possible. Like glue to the joiner, it is indispensable in many cases ; but like glue also, it is in ommon practice made to cover many defects, and much bad work, that ought not to exist. The soft solder used by plumbers on account of its melting easily is a composi tion of tin and lead in equal parts, fused together, and run into moulds in shape not unlike the bars of a gridiron. In the operation of soldering, the surfaces of the metal intended to be joined are scraped and rendered very clean ; they are then brought close together, and sprinkled with resin or borax at the joints to prevent oxidation while soldering. The heated solder is then brought in a ladle and poured on the joint, and smoothed and finished by a hot grozing iron and rubbed down with a cloth. Sheet lead, whether cast or milled, is supplied of various Sheet le weight or thickness, and is always described as of such weight (4 to 12 pounds) to the superficial foot. There are very few purposes, indeed, in building, in which lead of less than 6 ft) to the foot should be used, and very few in which the weight needs to exceed 10. For roofs, flats, and gutters, under ordinary circumstances, 7 or 8 Ib lead is a very fair and sufficient average ; for hips and ridges, lead of G ft) to the foot is thick enough ; and for flashings 6 Ib lead need not be objected to. Cast lead has been pre- Cast an&amp;lt; ferred for the former purposes, because its surface is milledle harder, but milled lead is of more even thickness through out, bends without cracking, which is not always the case with cast lead, and makes neater work. Sheets of cast lead run from 16 to 18 feet long and G feet wide ; milled sheets are made of about the same width, and 6 or 8 feet longer than cast sheets. Neither the one nor the other may be safely used on flats, or in gutters exposed to the wide range of temperature of our climate, in pieces of more than half the length and half the breadth of a sheet ; that is to say, from 8 to 12 feet long, and 3 feet wide, are the limits within which sheet lead will expand and contract without puckering and cracking ; and to allow it to move freely it is laid with rolls and drips in such a manner that any extent of surface may be covered with the effect of continuity, though the pieces of lead forming the covering be of such small sizes as above stated. But all facing, whether by soldering or otherwise, is to be carefully avoided. A roll is a piece of wood made about 2 inches Rolls, thick and 2| inches wide, rounded on one edge, and fixed with that edge uppermost, so as to come 4 inches within half the width of a sheet, that the edges may be turned up and folded round and over it, being lapped by, or lapping the edge of the adjoining sheet (Plate XXVI. fig. 7). Lead sufficiently stout, dressed neatly and closely down to the boards under it, and over the rolls at its edges, will require no fastening of any kind, unless it be so light as to be movable by the wind. Soils are used mostly in roofs and fiats ; drips principally in gutters, though they may bo required in long flats. The drip is formed in the first instance by the carpenter in laying the gutter boards, according to an arrangement with the plumber. It is a difference made in the height of the gutter of from 1 inches to 3 inches, where one sheet terminates in length, and meets another in continuation. The end of the lower is turned up against the drip, and that of the upper is dressed down over it, so as effectually to prevent the water from driving up under it. Where the fall is not great, a piece should be cut out across the higher gutter board, so that the top of the under-lead may lie level with the board. Gutters should have a fall of at least an eighth of an inch to Gutter the foot, and in flats it should be rather more, for such a covering is only so called in contradistinction to the pitch of a roof ; ends and sides which are against a wall should