Part 227

Spark coil. (Elec.) (a) An induction coil, esp. of an internal-combustion engine, wireless telegraph apparatus, etc. (b) A self- induction coil used to increase the spark in an electric gas-lighting apparatus.

Spark gap. (Elec.) The space filled with air or other dielectric between high potential terminals (as of an electrostatic machine, induction coil, or condenser), through which the discharge passes; the air gap of a jump spark.

Spark plug. In internal-combustion engines with electric ignition, a plug, screwed into the cylinder head, having through it an insulated wire which is connected with the induction coil or magneto circuit on the outside, and forms, with another terminal on the base of the plug, a spark gap inside the cylinder.

Spat, n. [Short for Spatterdash.] 1. A legging; a gaiter. [Scot. & Dial. Eng.]

2. A kind of short cloth or leather gaiter worn over the upper part of the shoe and fastened beneath the instep; -- chiefly in pl.

Spec`tro*bo*lom"e*ter (?), n. (Physics) A combination of spectroscope and bolometer for determining the distribution of energy in a spectrum. -- Spec`tro*bo`lo*met"ric (#), a.

Spec`tro*e*lec"tric (?), a. Pert. to or designating any form of spark tube the electric discharge within which is used in spectroscopic observations.

Spec"tro*gram (?), n. [Spectrum + -gram.] (Physics) A photograph, map, or diagram of a spectrum.

Spec"tro*graph (?), n. [Spectrum + graph.] (Physics) (a) An apparatus for photographing or mapping a spectrum. (b) A photograph or picture of a spectrum. -- Spec`tro*graph"ic (#), a. -- Spec`tro*graph"ic*al*ly (#), adv. -- Spec*trog"ra*phy (#), n.

Spec`tro*he"li*o*gram` (?), n. [Spectrum + heloi- + -gram.] (Astrophysics) A photograph of the sun made by monochromatic light, usually of the calcium line (k), and showing the sun's faculæ and prominences.

Spec`tro*he"li*o*graph (?), n. (Astrophysics) An apparatus for making spectroheliograms, consisting of a spectroscopic camera used in combination with a telescope, and provided with clockwork for moving the sun's image across the slit. -- Spec`tro*he`li*o*graph"ic (#), a.

Spec*trom"e*try (?), n. (Physics) Art or process of using the spectrometer, or of measuring wave lengths of rays of a spectrum. -- Spec`tro*met"ric (#), a.

Spec"tro*phone (?), n. [Spectrum + Gr. &?; sound.] An instrument constructed on the principle of the photophone and used in spectrum analysis as an adjunct to the spectroscope. -- Spec`tro*phon"ic (#), a.

Spec`tro*pho*tom"e*try (?), n. The art of comparing, photometrically, the brightness of two spectra, wave length by wave length; the use of the spectrophotometer. -- Spec`tro*pho`to*met"ric (#), a.

Spec*tros"co*py (?), n. The production and investigation of spectra; the use of the spectroscope; also, the science of spectroscopic phenomena.

Speed counter. (Mach.) A device for automatically counting the revolutions or pulsations of an engine or other machine; -- called also simply counter.

Speiss (?), n. (Metal.) Impure metallic arsenides, principally of iron, produced in copper and lead smelting.

Spell"bind` (?), v. t. [imp. & p. p. Spellbound (?); p. pr. & vb. n. Spellbinding.] To bind or hold by, or as if by, a spell or charm; to fascinate, esp. by eloquence of speech, as in a political campaign. -- Spell"bind`er (#), n.

||Sper`ma*toph"y*ta (?), n. pl. [NL.; spermato- + Gr. &?; plant.] (Bot.) A phylum embracing the highest plants, or those that produce seeds; the seed plants, or flowering plants. They form the most numerous group, including over 120,000 species. In general, the group is characterized by the marked development of the sporophyte, with great differentiation of its parts (root, stem, leaves, flowers, etc.); by the extreme reduction of the gametophyte; and by the development of seeds. All the Spermatophyta are heterosporous; fertilization of the egg cell is either through a pollen tube emitted by the microspore or (in a few gymnosperms) by spermatozoids. The phrase "flowering plants" is less distinctive than "seed plants," since the conifers, grasses, sedges, oaks, etc., do not produce flowers in the popular sense. For this reason the terms Anthrophyta, Phænogamia, and Panerogamia have been superseded as names of the phylum by Spermatophyta.

Sper"ma*to"phyte` (?), n. Any plant of the phylum Spermatophyta. -- Sper`ma*to*phyt"ic (#), a.

Sperm"ism (?), n. [Gr. &?; seed, sperm + -ism.] (Biol.) The theory, formerly held by many, that the sperm or spermatozoön contains the germ of the future embryo; animalculism.

Spi"der stitch. A stitch in lace making used to fill in open spaces with threads resembling a cobweb.

Spin"drift (?), n. Same as Spoondrift.

The ocean waves are broken up by wind, ultimately producing the storm wrack and spindrift of the tempest-tossed sea.

J. E. Marr.

Spi*nes"cence (?), n. The state or quality of being spinescent or spiny; also, a spiny growth or covering, as of certain animals.

Spin"i*fex (?), n. [NL.; L. spina spine + facere to make.] 1. (Bot.) A genus of chiefly Australian grasses, the seeds of which bear an elastic spine. S. hirsutus (black grass) and S. longifolius are useful as sand binders. S. paradoxusis a valuable perennial fodder plant. Also, a plant of this genus.

2. Any of several Australian grasses of the genus Tricuspis, which often form dense, almost impassable growth, their leaves being stiff and sharp-pointed.