SCA 



SCH 



to hollow out). A family of the macro- 

 trachian bivalves, named from the genus 

 saxicava; the inhabitants of these shells 

 are perforating animals, as the name 

 denotes. 



SAXICOLI'N^ {saxum, a stone, colo, 

 to inhabit). Saxicoline birds, or Stone- 

 chats; a family of the Cantatrices of 

 Macgillivray. Being intimately allied to 

 the Turdinae, Alaudinae, and Sylviinae, 

 they present no abrupt and decided cha- 

 racters by which they can be easily de- 

 fined. Most of them are migratory. 



SAXONY BLUE. An intensely deep 

 blue, imparted by dyeing with sulphate 

 of indigo. 



SCAGLIO'LA {scaglia, Ital., a scale). 

 An artificial composition employed for 

 making columns, and consisting of pure 

 gypsum, Flanders glue, isinglass, &c. 



SCALE {scala, a ladder). A line di- 

 vided into a marked number of small 

 and equal parts, applied as a measurer 

 of other lengths which are not so di- 

 vided, in order to ascertain their relative 

 dimensions. 



Plane diagonal decimal scale. This 

 instrument consists of a ruler divided 

 into a certain number of equal parts, 

 and these parts, by a particular con- 

 trivance, are again subdivided decimally, 

 or into tenths and hundredths of these 

 parts. By this instrument we are en- 

 abled, though with no great degree of 

 accuracy, to draw lines which shall bear 

 to each other nearly any proportions we 

 may please to assign them. 



SCALE OF NOTATION. A system 

 of notation in which each figure of a 

 number increases its value in a certain 

 proportion in proceeding from right to 

 left. The number, according to whose 

 powers the values proceed, is called the 

 radix of the scale. This number is con- 

 ventional, and there may, consequently, 

 be any number of different scales, each 

 of which has its own radix. When the 

 radix is 2, the scale is called binary ; 

 when 3, ternary; when 10, denary, or 

 decimal; when 12, duodenary, ox duodeci- 

 mal ; &c. 



SCALE'NE (o-KaXuvof, unequal). A 

 geometrical term applied to a triangle 

 which has three unequal sides. 



SCANSO'RES (scando, to climb). 

 Scandrices. Climbers ; a group of birds, 

 so named from their great facility in 

 climbing the branches of trees, including 

 the woodpeckers, the cuckoos, the tou- 

 cans, and the parrots. The external toe 

 is turned backward, as well as that 

 296 



which is posterior in the Rasores, so 

 that they have two posterior and two 

 anterior toes. 



SCAPE. A botanical term denoting 

 that form of inflorescence, in which the 

 axis of stemless plants proceeds imme- 

 diately from the ground, or near it, as in 

 cowslip. 



SCA'PHITE (o-Ka0o9, a bo^t). A genus 

 of fossil cephalopods, of a boat-like form. 

 SCA'POLITE (o-KciTrof, a rod, XiBoi, a 

 stone). Pyramidal felspar ; a substance 

 now classed under the general name 

 Wernerite. Scapolite is divided by Jame- 

 son into four sub-species, viz. radiated, 

 foliated, compact red, and elaolite. 



SCARABiE'ID^ {scarahceus, a beetle). 

 A large group of beetles constituting the 

 principal part of the section Lamelli- 

 comes. They are distinguished from 

 the other section, or the LucanidcB, 

 chiefly by the structure of their antennae, 

 which are proportionately shorter. 



SCA'RBROITE. Hydrated silicate of 

 alumina, occurring in veins in the beds 

 of sandstone covering the calcareous 

 rock near Scarborough, between septa of 

 oxide of iron. 



SCARI'TIDiE. A family of Coleo- 

 pterous insects, belonging to the section 

 Geodephaga, and named from the genus 

 scarites. 



SCELIDOTHE'RIUM (^KeXip, the 

 thigh, Otiplov, a beast). An animal of 

 the megatheroid type, exhibiting a tran- 

 sition to the ant-eater and armadillo, 

 which it resembles more than the sloth 

 in the form and structure of the skull. 



SCHAALEN BLENDE. Testaceous 

 blende ; a sulphuret of zinc, containing 

 iron and lead. The most characteristic 

 specimens are found at Geroldseck in the 

 Brisgau. 



SCHAALSTEIN. Tabular spar or 

 table spar; a silicate of lime, occurring 

 in primitive rocks, where it is associated 

 with brown garnets. This is the pris- 

 matic augite of Jameson. 



SCHAUM EARTH. Aphrite, or 

 earth foam; a carbonate of lime, oc- 

 curring usually in a friable, but some- 

 times in a solid state, with a shining 

 lustre, between semi-metallic and pearly. 

 SCHEAT. A star of the third magni- 

 tude in the constellation Aquarius. 



SCHEELE'S GREEN. Arsenite of 

 copper ; a green pigment. 



SCHEE'LIUM. Pyramidal tungsten ; 

 an ore of tungsten, named from Scheele, 

 its discoverer. Scheelite is a tungstate 

 of lime; scheel-lead ore, a tungstate of 



