Lead joint to Lens

Lead joint to Leather

Lead joint. (Plumb.) Usually means the making of a joint by pouring molten lead into the annular space between a bell and spigot and then making the joint tight by calking.
Lead monoxide. (litharge) (Chern.) PbO. A yellow to yellowish-red powder obtained by heating lead in air. Used in making lead glass, enamel, and glaze for earthenware. Mixed with glycerin it makes an excellent cement for the stopping of leaking joints. A second variety is known as massicot.
Lead paint. (Paint.) Ordinary paint, so called because white lead is used as a base.
Lead peroxide. (Chern. and Elec.) PbOr The lead compound from which the positive plates of electric storage batteries are made.
Lead poisoning. A disease affecting painters and workers in lead or lead products.
Leads. (Print.) Strips of metal used in spacing lines of type; made in multiples of points.
Lead screw. (Mach.) The screw which runs longitudinally in front of the bed of a screw-cutting lathe.
Lead sponge. (Elec.) The active ele­ment in the negaitve plate of a storage battery.
Lead storage cell. A device consist­ing of plates of lead peroxide and spongy lead in an electrolyte of sui ph uric acid. Used for storing chemical energy which on the clos­ing of a circuit will deliver an elec­trical Current.
Lead tetraethyl. (Chern.) Pb(C2H5)4' The important constituent of an­tiknock gasoline.
Lead wool. (Plumb.) A lead fiber used in place of molten lead in making pipe joints.
Leaf. (Bookbndg. and Print.) A sin­gle, unfolded, piece of paper, or a single division of a folded sheet of paper, as in a book.
Leaflet. (Bookbndg. and Print.) A fold~r, a tract, or small printed booklet of only a few pages.
Leaf spring. A spring made up of several t1at plates superimposed one upon another, such as used on automobiles, wagons, cars, etc.
Leafwork. (Furn.) Small aggre­gations of leaves carved upon the legs and splats of chairs and other details of furniture. Extensively used by most of the cabinetmakers of the last quarter of the eighteenth century.
League. 15,840 ft. = 5280 yd. = 3 miles, sometimes considered as 3 knots or nautical miles.
Leak. The loss of CUITent from a conductor, usually resulting from poor insulation..
Lean mixture. (Auto.) A fuel mix­ture which contains too much air in proportion to gasoiine.
Lean-to roof. (Arch.) A wing or ex­tension to a building, with a roof sloping in only one direction, away from the main buildirig.
Lease. (Textile) The crossing made in warp threads in preparing them for the loom.
Leather. (Fum.) Dressed hides used for upholstering, often stalnpcd and coloured.

Leather board to Lens acoustic
Leather board. Made by pulping various fibrous materials, mixed with chalk or whiting. It is mold~ into form and coated with a glaz­ing solution consisting of starch, gelatin, and turpentine.
Leather-craft. Ornamentation of leather by means of tools.
Leatherette cover paper. (Paper) An imitation leather cover paper.
Leather fillet. A strip of leather glued in the angles of foundry patterns, to increase strength of the casting and to eliminate sharp edges in the foun­dry sand.
Leatheroid. (Bookbndg.) A material resembling leather; usually made by treating vegetable fibers with certain chemicals.
Leclanche cell. (Elec.) An open-cir­cuit primary cell using carbon and zinc electrodes, sal-ammoniac elec­trolyte, and manganese dioxide depolarizer.
Lectern. (Furn.) A reading desk. Ledge. (Arch.) A shelflike projection as from a wall.
Ledger board. (Arch.) Same as ribbon strip; attached to studding to carry joists.
Ledger paper. (Papermkg.) A strong . paper, having a surface adequate for pen writing and erasure which is used for accounting and recording.
Left-hand engine. (Aero.) An engine whose propeller shaft, to an ob­server facing the propeller from the engine end of the shaft, rotates in a counter clockwise direction.
Left-hand screw. (Mech.) A screw which advances when turned from right to left.

Left-hand thread. (Mach.) A screw thread so cut that the bolt, screw, or nut has to be turned in a coun­ter-clockwise motion to engage or tighten it.
Left-hand tool. (Mach.) Side tool ground to an angle on the right­hand side, and which, therefore, cuts from left to right.
Leg. (Furn.) Supporting member of a piece of furniture.
Legal cap. (Papermkg.) A size of writing paper, 8.5 by 14 in.
Legend. (Print.) Descriptive data or specification accompanying or re­lating to an illustration.
Lehr. An annealing oven used in glass factories in which glass is allowed to cool.
Length. The greatest dimensioll of a body. Distance measured from end to end. Extent in point of time, duration, continuance.
Lengthening bar. (Draw.) An ap­pendage to compasses used in securing a greater radius than could otherwise be had.
Lens. A piece of transparent sub­stance, usually glass, having one or more curved surfaces used in changing the convergence of light rays. as for magnification Of COf­rection of defects of vision.
Lens, Acoustic. An acoustic lens is a device placed in front of some compression driver/high frequency horn assemblies to further control the dispersion of sound and loading on the driver. The lens operates on . principle similar to an optical lens, although rather than glass it is made of metal with a series of slits or