Part 394

Si"lent*ly (?), adv. In a silent manner.

Si"lent*ness, n. State of being silent; silence.

Si*le"nus (?), n. [L. Silenus the tutor and attendant of Bacchus.] (Zoöl.) See Wanderoo.

Si*le"si*a (?), n. 1. A kind of linen cloth, originally made in Silesia, a province of Prussia.

2. A twilled cotton fabric, used for dress linings.

Si*le"si*an (?), a. Of or pertaining to Silesia. -- n. A native or inhabitant of Silesia.

Si"lex (?), n. [L., a finit, a pebblestone.] (Min.) Silica, SiO2 as found in nature, constituting quarz, and most sands and sandstones. See Silica, and Silicic.

Sil`hou*ette" (?), n. [F.; -- so called from Etienne de Silhoutte, a French minister of finance in 1759, whise diversion it was to make such portraits on the walls of his apartments.] A representation of the outlines of an object filled in with a black color; a profile portrait in black, such as a shadow appears to be.

Sil`hou*ette", v. t. To represent by a silhouette; to project upon a background, so as to be like a silhouette. [Recent]

A flock of roasting vultures silhouetted on the sky.

The Century.

Sil"i*ca (?), n. [NL., from L. silex, silics, a flint.] (Chem.) Silicon dioxide, SiO&?;. It constitutes ordinary quartz (also opal and tridymite), and is artifically prepared as a very fine, white, tasteless, inodorous powder.

Sil"i*cate (?), n.[Cf. F. silicate.] (Chem.) A salt of silicic acid.

In mineralogical chemistry the silicates include; the unisilicates or orthosilicates, salts of orthosilicic acid; the bisilicates or metasilicates, salts of metasilicic acid; the polysilicates or acid silicates, salts of the polysilicic acids; the basic silicates or subsilicates, in which the equivalent of base is greater than would be required to neutralize the acid; and the hydrous silicates, including the zeolites and many hydrated decomposition products.

Sil"i*ca`ted (?), a. (Chem.) Combined or impregnated with silicon or silica; as, silicated hydrogen; silicated rocks.

Silicated soap, a hard soap containing silicate of soda.

Sil`i*ca*ti*za"tion (?), n. Silicification.

||Si*lic"e*a (?), n. pl. [NL.] (Zoöl.) Same as Silicoidea.

Si*li"ceous (?), a. [L. siliceus, fr. silex, silicis, a flint.] Of or pertaining to silica; containing silica, or partaking of its nature. [Written also silisious.]

Si*lic"ic (?), a. [L. silex, silicis, a flint: cf. F. silicique.] (Chem.) Pertaining to, derived from, or resembling, silica; specifically, designating compounds of silicon; as, silicic acid.

Silicic acid (Chem.), an amorphous gelatinous substance, Si(HO)4, very unstable and easily dried to silica, but forming many stable salts; -- called also orthosilicic, or normal silicic, acid.

Si*lic`i*cal*ca"re*ous (?), a. Consisting of silica and calcareous matter.

Sil"i*cide (?), n. (Chem.) A binary compound of silicon, or one regarded as binary. [R.]

Hydrogen silicide (Chem.), a colorless, spontaneously inflammable gas, SiH4, produced artifically from silicon, and analogous to methane; -- called also silico-methane, silicon hydride, and formerly siliciureted hydrogen.

Sil`i*cif"er*ous (?), a. [L. silex, silicis, a flint + -ferous.] Producing silica; united with silica.

Si*lic`i*fi*ca"tion (?), n. [See Silicify.] (Chem.) Thae act or process of combining or impregnating with silicon or silica; the state of being so combined or impregnated; as, the silicification of wood.

Si*lic"i*fied (?), a. (Chem.) Combined or impregnated with silicon or silica, especially the latter; as, silicified wood.

Si*lic"i*fy (?), v. t. [imp. & p. p. Silicified (?); p. pr. & vb. n. Silicifying (?).] [L. silex, silicis, a flint + -fy: cf. F. silicifier.] (Chem.) To convert into, or to impregnate with, silica, or with the compounds of silicon.