SAT 



SAX 



SAPONIFICATION {sapo, soap, fio, 

 to become). The conversion of any sub- 

 stance into soap. 



SAPPHIRE. A variety of rhomboidal 

 corundum, constituting the ruby and the 

 oriental top&z. 



SA'RCOCARP (o-cipf, capKof, flesh, 

 Kapnoi, fruit). The name given by 

 some botanists to the parenchyma, or 

 fleshy part of fruits, lying between the 

 epicarp or skin, and the endocarp or 

 stone. See Pericarp. 



SA'RCODERM (o-cipf, aapKo^y flesh, 

 dep/ia, skin). A term applied by De 

 Candolle to the substance which occurs 

 between the integuments of the seed, 

 analogous to the sarcocarp of fruits. 



SARCO'PHAGA {aap^, flesh, 4>dya), 

 to eat). Flesh-eating animals ; a term 

 synonymous with the more usual one 

 zoophaga, and, like this, employed in 

 contradistinction to that of phytophaga. 



SARD, or SARDOIN. A variety of 

 chalcedony, of a brownish yellow colour, 

 said to be found in Sardinia. 



SA'RDONYX. A variety of onyx, in 

 which the opaque white alternates with 

 a rich deep orange brown of considerable 

 translucency. The name is said to be 

 derived from that of Sardes, in Lydia, 

 whence the stone was brought. By 

 others it is referred to Sardo, the Greek 

 name of Sardinia, whence the Cartha- 

 ginians are said to have exported it. 



SARGA'SSO. The fucus natans, or 

 gulf-weed, which is spread over a consi- 

 derable part of the surface of the Atlantic, 

 beginning on the east at the 30th meri- 

 dian, and extending on the west to the 

 Bahama Islands. Its northern limit may 

 be placed at 36° n. lat., and its southern 

 at 19° N. lat. The abundance of this weed 

 has led to the Portuguese expression of 

 Mar de Sargasso, or Weedy Sea. 



SARME'NTUM. The name given by 

 some botanists to the modification of 

 the aerial stem called a runner. 



SAROS. A Chaldean name applied, 

 according to some writers, to an astro- 

 nomical period of 18 years and 10 or 11 

 days, according as the 18 years have 5 or 

 4 leap-years. Berosus, however, speaks 

 of the ' saros of 3600 years. It is, pro- 

 bably, not a chronological period, but 

 only a portion of time with any arbitrary 

 commencement. 



SA'SSOLINE. Native boracic acid, 

 found on the edges of hot springs near 

 Sasse, in the territory of Florence. 



SATELLITE {satelles, a life-guard). 

 A secondary planet, or moon, so named 

 295 



from its attending a primary planet, as a 

 prince is attended by his satellites or 

 life-guards. See Planet. 



SATIN SPAR. A fibrous limestone 

 with a pearly lustre, from Cumberland. 

 It consists chiefly, if not entirely, of 

 carbonate of lime. 



SATURATION (saturo, to satisfy). 

 In the language of Chemistry, a fluid is 

 said to be saturated with a substance, 

 when it holds as much of this substance 

 in solution as it can dissolve. Thus, 

 water is said to be saturated with com- 

 mon salt, when it has dissolved about 

 one-third of its weight of the latter : it 

 will not dissolve any more. 



Again : when two principles, which 

 have united to form a new body, are in 

 such proportion that neither predomi- 

 nates, they are said to be saturated with 

 each other, or the aflinities are said to be 

 satisfied. If otherwise, tlie predominant 

 principle is said to be sub-saturated, or 

 under-saturated^ and the other super- 

 saturated, or over-saturated. 



SATURN. A planet 900 times larger 

 than the earth, revolving on its axis in 

 10^ hours, and performing its orbit 

 round the sun in twenty-nine years, five 

 months, and fourteen days. It is ac- 

 companied by eight satellites, and is 

 surrounded by two luminous rings. 



SAU'RIANS (o-at'/pa, a lizard). An 

 order of Reptiles, in which the ribs are 

 moveable, and there are one or two pairs 

 of external members. It comprehends 

 all the lizard tribe, which are inteir 

 mediate between the Loricata and the 

 Serpents. 



SAU'ROID FISHES {aavpa, a lizard, 

 etdor, resemblance). A tribe of fishes, 

 exhibiting strong saurian or reptilian 

 analogies, chiefly in the teeth. The ex- 

 isting sauroid fishes consist of seven 

 species only, five belonging to the genus 

 lepidosteus, or bony pike, and two species 

 of polypterus, one from the Nile, the 

 other from the Nif?er. 



SAU'SSURITE. Axe-stone ; jade. A 

 mineral found by Saussure on the bor- 

 ders of the lake of Geneva, consisting 

 principally of silica and alumina with 

 oxide of iron. 



SAVANNA or PRAIRIE. The name 

 given to the vast plain constituting the 

 central part of North America, from the 

 Frozen Ocean to the Gulf of Mexico, 

 watered by the Missouri and the Missis- 

 sippi. This immense tract of country is 

 estimated at 2,430,000 square miles. 



SAXICA'VIDiE {saxum, a stone, cavo, 

 04 



