Scintillation to Screw

Scintillation counter to Scrap
lous effect of the light of the stars.
Scintillation counter. A device employing scintillation for detec­ting and measuring radio activity.
Scissors truss. (Arch.) A type of roof truss, so named from its resem­blance to a pair of scissors. It is frequently used for supporting roofs over halls and churches.
Sclerometer. (Engin.) An instrument for determining the hardness of metals by drawing a diamond once forward and once backward over a smooth surface; the resulting scratch is compared with a stan­dard scratch.
Scleroscope. (Engin.) An instrument for measuring the hardness of metals. A diamond pointed plunger is dropped vertically on a test specimen. The height of rebound is a measure of the hardness of the material.
Sconce. (Bldg.) An ornamental bracket holding candles or lantern.
Scoop. (Tel.) A type of single lamplight reflector.
Scope. Range of view; outlook; appli­cation; an instrument for viewing.
Score. (Auto.) A groove, scratch, or mark caused by burning or abrad­ing in moving parts.
Scored cylinders. (Auto. Mech.) Cy­linders of automobile or other engines in which the smooth polished surfaces of the cylinder walls have been cut into or scored by broken piston rings or loose wrist pins, or by the admission of some foreign substance into the cylinders.

Scored dmm. (Atuo.) A brake drum scored or grooved. This often occurs when the brake lining be­comes badly worn due to harsh braking effort or exposed heads of rivets, or both, which produce grooves and ridges' inside the surface of the drum.
Scoring. (Cabwk.) Striking lines or grooves across the grain on a piece of wood with any steel instrument, for the purpose of roughing the surface, in order to make a firmer glued joint. (Print.) Grooving heavy paper or carboard with a plane rule upon a press, by a heavy uninked impression, for the pur­pose of folding.
Scoring of pistons and cylinders. (Auto.) Roughening surfaces of these parts due to improper lubri­cation.
Scoring or creasing rule. (Print.) A rule printed to secure exact creas­ing and folding. When given a heavy impression the resulting crease makes cover stock or board less likely to break on the fold.
Scotch tape. A strip of paper supplied with an adhesive on one side, used in the drafting room for holding down drafting paper, and by painters for covering surfaces not to be touched by the paint. Also a transparent adhesive for sealing packages, etc.
Scotia. (Arch.) A concave molding often found in the base of a col- . umn.
Scrap. (Fdry.) Pig iron that has been melted in the cupola and is to beScrap iron to Screw-and-nut steering gearmelted again.
Scrap iron. (Metal.) A term covering all grads of salvaged iron or steel to be used in making new steel.
Scrape. (Mach.) To finish a surface or to fit a bearing, etc., by the use of a hand tool called a scraper.
Scraped joint. (Mach.) A joint, as a bearing brought to a perfect fit by I' means of a scraper.
Scraper. (I) A flat plate of steel used by woodworkers to smooth wood surfaces. (2) A tool used by metal­workers for fitting bearings, and for turning surfaces. Metalworkers scrapers are of a variety of shapes, depending on the work to a done.
Scraper plane. (Woodwk.) A plane which carries a scraping blade. Used in scraping floors and smoothing large surfaces.
Scraping. (Mach.) A method of fini­shing flat surfaces and bearings, etc., by the use of a hand tool called a scraper. Scratch. Shallow mark, groove, fur­row, or channel on a surface.
Scratch awl. (Shopwk.) A sharp­ pointed piece of steel used for marking on metal.
Scratch brush. A wire brush used for removing rust, dirt, and foreign matter from metal surfaces.
Scratch coat. (Masonry) The first coat, which is scratched .in order to give a better hold for succeed­ing coats.
. Screeds. (Masonry) Strips pf plaster about 8 in. wide and the depth of the first two coats, which are put on first and are used as thicknessguides in applying the remainder of the plaster.
Screen. (Print.) The ruled glass screen used in halftone engraving. Its close or open rulin$ determines the fineness or coarSeness of the plate. (Tel.) A surface or area of material on which motion picture, television, radar, or other images are projected or formed; a plate of ground glass or the like on which the imag~ is brought into focus in a camera before being photo­graphed.
Screenings. (Papermkg.) A cheap paper, often packed, sometimes glazed; used for packing and wrapping.
Screw. (Mech.) A screw may be con­sidered as a helix wound around a cylinder; the helix may be single as a common screw, or double, or multiple.
Screw adjusting caliper. (Mach.) Similar in construction to the firm joint caliper but has in addition a spring and screw control for se­curing delicate adjustments.
Screw-and-nut steering gear. (Auto.) The lower end of the stearing-gear shaft has a double screw thread cut on it; one a right-hand, and the other, crossing it, a left-hand thread. When assembled, the threaded end of the shaft is en­gaged by two half nuts, one right­