GLOSSARY. 



167 



the capital ; in mechanics, an 

 axle of large size. 



Shale (Germ, scha'len, to peel off). 

 In geology, applied to all argilla- 

 ceous or clayey strata which split 

 up or peel off in thin laminae. 



Shemit'ic. See Semitic. 



Shingle. In geology, loose imper- 

 fectly rounded stones and pebbles. 



Sial'agogue (Gr. aia\ov, si'alon, 

 saliva ; ayw, ag'u, I lead). Pro- 

 moting a flow of saliva. 



Sibilant (Lat. rib'ilo, 1 hiss). Making 

 a hissing sound. 



Sidera'tion (Lat. sidus, a star). A 

 blasting or blast in plants ; a 

 sudden deprivation of sense. 



Side'real (Lat. sidus, a star). Rela- 

 ting to, or containing stars ; a 

 sidereal day is the period between 

 the moment at which a star is in 

 the meridian of a place, and that 

 at which it arrives at the meridian 

 again ; a sidereal year is the period 

 in which the fixed stars apparently 

 complete a revolution ; sidereal 

 period is the time which a planet 

 takes to make a complete revolu- 

 tion round the sun. 



Siderog'raphy (Gr. (nSypov, sideron, 

 iron ; ypatyw, graph' o, I write). 

 The art of engraving on steel. 



Sigilla'ria (Lat. sigil'lum, a seal). In 

 geology, a large genus of fluted 

 tree-stems having seal-like punc- 

 tures on the ridges. 



Sig'moid (C, the old form of the 

 Greek letter, ffiy/j.a, sigma ; flSos, 

 ei'dos, form). Like the Greek 

 letter C, or sigma ; applied in 

 anatomy to several structures in 

 the body. 



Sign (Lat. signum, a mark). In 

 astronomy, the twelfth part of the 

 ecliptic ; in algebra, a character 

 indicating the relation between 

 quantities ; in medicine, anything 

 by which the presence of disease is 

 made known ; physical signs are 

 phenomena taking place in the 

 body in accordance with physical 

 laws, and capable of being per- 

 ceived by the senses of the ob- 

 server. 



Silica (Lat. silex, flint). The com- 



pound of silicon with oxygen, form- 

 ing pure flint or rock-crystal. 



Silicate (Lat. silex, flint). A com- 

 pound of silicic acid with a base. 



Silic'eous (Lat. silex, flint). Belong- 

 ing to or containing silex or flint ; 

 having a flinty texture. 



Silic'ic (Lat. silex, flint). Belonging 

 to flint ; silicic acid, a name 

 applied to silica, or a compound 

 of silicon and oxygen having 

 certain of the properties of an 

 acid. 



Siliciferous (Lat. silex, flint ; fer'o, 

 I bear). Producing silex or flint. 



Silicifica'tion (Lat. silex, flint ; 

 fac'io, I make). Petrifaction ; 

 the conversion of any substance 

 into a flinty mass. 



Sili'cified (Lat. silex, flint ; fac'io, 

 I make). Converted into flinty 

 matter. 



Silic'ula (Lat. a little pod). A fruit 

 resembling a siliqua, but broader 

 and shorter. 



Silic'ulose (Lat. silic'ula, a little pod). 

 Bearing silieulse or silicles. 



Sil'iqua (Lat. a pod). A form of 

 fruit consisting of two long cells, 

 divided by a partition, having 

 seeds attached on each side, as in 

 the cabbage and turnip. 



Sil'iquose (Lat. sil'iqua, a pod), 

 bearing a siliqua. 



Silt. In geology, properly the fine 

 mud which collects in lakes and 

 estuaries, but generally used to 

 designate all calm and gradual 

 deposits of inud, clay, or sand. 



Silu'rian (Lat. Silu'res, the ancient 

 inhabitants of South Wales). Ap- 

 plied in geology to a system of 

 slaty, gritty, and calcareous beds, 

 containing occasional fossils, and 

 largely developed in South Wales. 



Sin'apism (Gr. ffivcnri, sina'pi, mus- 

 tard). A mustard poultice. 



Sin'ciput (Lat.) The fore part of the 

 head. 



Sine (Lat. sinus). In trigonometry, 

 the straight line drawn from one 

 extremity of the arc of a circle, 

 perpendicular to the diameter 

 passing through the other ex- 

 tremity. 



