Part 398

Si"lo (?), n. [F.] A pit or vat for packing away green fodder for winter use so as to exclude air and outside moisture. See Ensilage.

Silt (?), n. [OE. silte gravel, fr. silen to drain, E. sile; probably of Scand. origin; cf. Sw. sila, prob. akin to AS. seón to filter, sgan to fall, sink, cause to sink, G. seihen to strain, to filter, OHG. sihan, Icel. s>a, Skr. sic to pour; cf. Gr. &?;&?;&?; moisture. Cf. Sig, Sile.] Mud or fine earth deposited from running or standing water.

Silt, v. t. [imp. & p. p. Silted; p. pr. & vb. n. Silting.] To choke, fill, or obstruct with silt or mud.

Silt, v. i. To flow through crevices; to percolate.

Silt"y (?), a. Full of silt; resembling silt.

Si*lure" (?), n. [L. silurus a sort of river fish, Gr. &?;&?;&?;: cf. F. silure.] (Zoöl.) A fish of the genus Silurus, as the sheatfish; a siluroid.

Si*lu"ri*an (?), a. [From L. Silures, a people who anciently inhabited a part of England and Wales.] (Geol.) Of or pertaining to the country of the ancient Silures; -- a term applied to the earliest of the Paleozoic eras, and also to the strata of the era, because most plainly developed in that country.

The Silurian formation, so named by Murchison, is divided into the Upper Silurian and Lower Silurian. The lower part of the Lower Silurian, with some underlying beds, is now separated under the name Cambrian, first given by Sedwick. Recently the term Ordovician has been proposed for the Lower Silurian, leawing the original word to apply only to the Upper Silurian.

Si*lu"ri*an, n. The Silurian age.

Si*lu"ri*dan (?), n. (Zoöl.) Any fish of the family Siluridæ or of the order Siluroidei.

Si*lu"roid (?), n. [Silurus + -oid.] (Zoöl.) Belonging to the Siluroidei, or Nematognathi, an order of fishes including numerous species, among which are the American catfishes and numerous allied fresh-water species of the Old World, as the sheatfish (Silurus glanis) of Europe. -- n. A siluroid fish.

||Sil`u*roi"de*i (?), n. pl. [NL.] (zoöl.) An order of fishes, the ||Nematognathi.

||Si*lu"rus (?), n. [L. See Silure.] (Zoöl.) A genus of large ||malacopterygious fishes of the order Siluroidei. They inhabit the ||inland waters of Europe and Asia.

Sil"va (?), n.; pl. E. Silvas (#), L. Silvae (&?;). [L., properly, a wood, forest.] [Written also sylva.] (Bot.) (a) The forest trees of a region or country, considered collectively. (b) A description or history of the forest trees of a country.

Sil"van (?), a. [L. silva, less correctly sylva, a wood or grove, perh. akin to Gr. "y`lh; cf. L. Silvanus Silvanus the god of woods: cf. F. sylvain silvan. Cf. Savage.] Of or pertaining to woods; composed of woods or groves; woody. [Written also sylvan.]

Betwixt two rows of rocks, a silvan scene Appears above, and groves forever green.

Dryden.

Sil"van, n. (Old Chem.) See Sylvanium. [Obs.]

Sil"van*ite (?), n. (Min.) See Sylvanite.

{ Sil"vas (?) or Sel"vas (?) }, n. pl. [L. silva a forest, Sp. selva.] Vast woodland plains of South America.

Sil"vate (?), n. (Chem.) Same as Sylvate.

Sil"ver (?), n. [OE. silver, selver, seolver, AS. seolfor, siolfur, siolufr, silofr, sylofr; akin to OS. silubar, OFries. selover, D. zilver, LG. sulver, OHG. silabar, silbar, G. silber, Icel. silfr, Sw. silfver, Dan. sölv, Goth. silubr, Russ. serebro, Lith. sidabras; of unknown origin.] 1. (Chem.) A soft white metallic element, sonorous, ductile, very malleable, and capable of a high degree of polish. It is found native, and also combined with sulphur, arsenic, antimony, chlorine, etc., in the minerals argentite, proustite, pyrargyrite, ceragyrite, etc. Silver is one of the "noble" metals, so-called, not being easily oxidized, and is used for coin, jewelry, plate, and a great variety of articles. Symbol Ag (Argentum). Atomic weight 107.7. Specific gravity 10.5.

Silver was known under the name of luna to the ancients and also to the alchemists. Some of its compounds, as the halogen salts, are remarkable for the effect of light upon them, and are used in photography.

2. Coin made of silver; silver money.

3. Anything having the luster or appearance of silver.

4. The color of silver.

Silver is used in the formation of many compounds of obvious meaning; as, silver-armed, silver-bright, silver-buskined, silver-coated, silver-footed, silver-haired, silver-headed, silver-mantled, silver-plated, silver-slippered, silver-sounding, silver-studded, silver-tongued, silver-white. See Silver, a.

Black silver (Min.), stephanite; -- called also brittle silver ore, or brittle silver glance. -- Fulminating silver. (Chem.) (a) A black crystalline substance, Ag2O.(NH3)2, obtained by dissolving silver oxide in aqua ammonia. When dry it explodes violently on the slightest percussion. (b) Silver fulminate, a white crystalline substance, Ag2C2N2O2, obtained by adding alcohol to a solution of silver nitrate. When dry it is violently explosive. -- German silver. (Chem.) See under German. -- Gray silver. (Min.) See Freieslebenite. -- Horn silver. (Min.) See Cerargyrite. -- King's silver. (O. Eng. Law) See Postfine. -- Red silver, or Ruby silver. (Min.) See Proustite, and Pyrargyrite. -- Silver beater, one who beats silver into silver leaf or silver foil. -- Silver glance, or Vitreous silver. (Min.) See Argentine.