RUG 



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SAL 



1. In conchology, applied to shells which 

 are rugged and full of wrinkles. 



2. In botany, applied to leaves when the 

 veins are more contracted than the disc, 

 so that the disc rises into little inequali- 

 ties : the primrose and sage afford ex- 

 amples. 



3. In entomology, when longitudinal ele- 

 vations are placed irregularly on the sur- 

 face, resembling coarse wrinkles. 



RU'MINANTS. (from rumino, to chew over 

 again, Lat. ruminant, Fr. ruminante, It.) 

 Chewing the cud. 



RUMINA'NTIA. > The eighth order of Mam- 

 RU'MINANTS. J malia, or those animals 

 that chew the cud. These animals pos- 

 sess the singular property of returning 

 the food to the mouth after it has been 

 swallowed, that it may undergo the pro- 

 cess of a second mastication. This pro- 

 perty depends upon the structure of the 

 four stomachs which these animals pos- 

 sess, the three first being so arranged 

 that the food may pass from the oesopha- 

 gus into either of them. Cuvier divides 

 this great order into those that have 

 horns, and those that have none. 



RU'NCINATIT. (from runcina, a saw, Lat.) 

 In botany, a term applied to leaves whose 

 edges are cut into teeth turning back- 

 wards like a scythe. 



RUST, (rout, Germ.) If iron be exposed 

 to the air, more especially if the at- 

 mosphere be moist, its surface is soon 

 tarnished, and it is gradually changed 

 into a brown or yellow! powder, well 

 known by the name of rust. Rust 

 is an oxide of iron, or of some other 

 metal. 



RU'TILE. Red oxide of titanium. The 

 titane oxyde of Haiiy ; titane ruthil of 

 Brongniart ; rutil of Werner ; peritomes 

 titan-erz of Mohs. A brown, red, yel- 

 low, and sometimes nearly velvet-black 

 ore. Occurs regularly crystallized, mas- 

 sive, disseminated, in angular grains and 

 in flakes. External lustre considerable, 

 and sometimes metallic. Opaque or 

 translucent. Scratches glass. Specific 

 gravity = 4'2 to 4'4. It is infusible 

 before the blow-pipe unless a flux be em- 

 ployed. It is found in Scotland, in the 

 granite of Cairngorm. 



RYA'KOLITE. A name lately given to 

 glassy felspar. 



SA'CCHAROID. (from ffaicxap, sugar, and 

 fidof, form, Gr.) A term applied to 

 rocks which have a texture resembling 

 that of loaf-sugar. 



SA'CRAL. Pertaining to the sacrum. 



SA'CRUM. (Lat.) The bone which forms 

 the basis of the vertebral column. 



SADDLE-SHAPED STRATA. When strata 

 are bent on each side of a mountain, 

 without being broken at the top, they are 

 called saddle- shaped. BakewelL 



SA'GENITE. Another name for rutile, or 

 red oxide of titanium. See Rutile. 



SAGI'TTA. An obsolete name for belemnite. 



SAGI'TTATE. (from sayittatus, Lat.) Ar- 

 row-shaped. 



SA'HLITE. The sahlit of Werner ; the 

 malacolith of Brongniart. A variety of 

 augite, discovered in a silver mine at 

 Sahla, in Sweden, from which it takes its 

 name. It is of a green colour of various 

 shades. It occurs in straight, lamellar, 

 and granular concretions, sometimes crys- 

 tallized, with a shining, vitreous, or 

 pearly lustre ; translucent at the edges. 

 It is soft to the touch, scarcely scratches 

 glass, and is easily scratched by a knife. 

 Specific gravity 3'2. Before the blow- 

 pipe it melts, with some ebullition, into a 

 porous glass. It consists of silica 53, 



magnesia 19, lime 20, alumina 3, iron and 

 manganese 4. 



SA'LAMANDER. (craXapavdpa, Gr. sala- 

 mandra, Lat. salamandre, Fr. salaman- 

 dra, It. salamander, Germ.) A genus of 

 reptiles belonging to the order Batrachia. 

 The salamander possesses the general 

 form of the lizard, and is placed by Lin- 

 naeus among the lizards ; but its charac- 

 ters are those of the Batrachians. Its 

 body is elongated ; it has four feet, and a 

 long tail. When arrived at an adult 

 state, its respiration is performed in the 

 same manner as in frogs and tortoises. 

 Aristotle and Pliny state that if the sala- 

 mander passes through fire, the fire is 

 immediately extinguished, and that it 

 emits a milky saliva, which is depilatory. 

 Bosc says that it emits from its skin a 

 milky fluid when annoyed, and when put 

 into the fire, it sometimes happens that 

 this fluid sufficiently extinguishes it to 

 permit the animal to escape. This se- 

 cretion of a milky fluid appears to be 

 exceedingly acrid ; produces, if applied to 

 the tongue, a very painful sensation ; is 

 an excellent depilatory, and destroys 

 small animals. Spallanzani has disco- 

 vered that the salamander has the power 

 of reproducing lost or mutilated organs, 



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