sue 



SUL 



SUBLIME GEOMETRY. By the 



older mathematicians this term was 

 technically applied to the higher parts 

 of geometry, in which the infinitesimal 

 calculus, or something equivalent, was 

 employed. 



SUBSIDIARY. A quantity or symbol 

 is so called when it is not essentially a 

 part of a problem, but is introduced to 

 help in the solution. The terra is par- 

 ticularly applied to those angles, which 

 are introduced into trigonometrical pro- 

 blems, in which there is no question of 

 angular quantity. 



SUBSTANCE. In Physics, substance 

 is synonymous with matter. In meta- 

 physics, it is that which supports, or, 

 literally, stands under phenomena ; it is 

 the fundamental fact of all existence, 

 though as inconceivable as a point in 

 mathematics. 



SUBSTITUTION, CHEMICAL. A 

 term explanatory of certain phenomena 

 connected with chemical affinity. When 

 carbonate of soda is added to nitrate of 

 lime, carbonate of lime is instantly formed 

 and precipitated, while nitrate of soda is 

 formed at the same time, and remains in 

 solution. Here a double substitution 

 occurs, lime being substituted for soda 

 in the carbonate, and soda for lime in 

 the nitrate. Such reactions may, there- 

 fore, be truly described as double substi- 

 tutions as well as double decompositions. 

 The substitution of chlorine for hydrogen 

 in many organic substances has been 

 found to take place with remarkable uni- 

 formity. 



SUBTRACTION. The arithmetical 

 operation of removing one number or 

 quantity from another, in order to find 

 their diflference. The operation is pre- 

 cisely the reverse of addition. The quan- 

 tity to be diminished was formerly called 

 the minuend ; the quantity to be removed, 

 the subtrahend ; and the remaining quan- 

 tity or difference, the remainder, 



SUCCINIC ACID {succinum, amber). 

 An acid derived from the distillation of 

 amber, and found also in the resin of some 

 coniferous plants. Its compounds with 

 the salifiable bases are called succinates. 



SUCKER. Surculus. A term applied 

 in Botany to a modification of the aerial 

 stem, consisting of a branch which pro- 

 ceeds from the neck of a plant beneath 

 the surface of the ground, and becomes 

 erect as soon as it emerges from the 

 earth, producing leaves and branches, 

 and subsequently roots. It has been 

 termed soholes. 

 321 



SUCTION {sugo, to suck). The act of 

 sucking; a term applied to the raising 

 of liquids through a tube, by means of a 

 piston, which lifts and sustains the weight 

 of the atmosphere from that part of the 

 well which is covered with the tube, 

 leaving it to press on the other parts of 

 the surface. See Pump. 



SUCTO'RIA {sugo, to suck). A class 

 of articulate animals, which have their 

 mouth adapted for sucking fluid aliment. 

 The following orders are founded on 

 diflTerences of the general form of the 

 body :— 



1. Cystica, or those destitute of an 

 anal aperture, which have one or more 

 buccal orifices leading into a terminal 

 cyst. 



2. Cestoidea, or those with a long, de- 

 pressed, flat, articulated form, without 

 anal aperture. 



3. Trematoda, or those with a short, 

 broad, depressed body, without distinct 

 anus, and with one or more orifices, 

 leading into a ramified alimentary 

 canal. 



4. Acanthocephala, or those with an 

 elongated cylindrical body, with the an- 

 terior part closely covered with small 

 sharp spines; the oral aperture leading 

 to a ramified alimentary canal destitute 

 of anal opening. 



5. Nematoidea, or those with a long, 

 cylindrical and often filiform, naked, 

 inarticulated body traversed by a straight 

 alimentary canal open at both ends, and 

 with distinct sexes and internal impreg- 

 nation. 



6. Epizoa, or those of a more short 

 and entomoid form, with a sub-articu- 

 lated trunk, a biforate intestine, with 

 rudimentary mandibles, palpi, proboscis, 

 and sometimes antennae and eyes. — 

 Grant. 



SVFFIX {suffigo, to fasten). A term 

 applied by some mathematicians to the 

 index written under letters, as in a , a^, 

 &c. 



SUFFRUTEX. An under-shrub; a 

 plant which differs from the frutex, or 

 shrub, in its perishing annually, either 

 wholly or in part ; and from the herb, in 

 having branches of a woody texture, 

 which frequently exist more than one 

 year, as in the Tree Mignonette. 



SU'IDiE {sus, suis, a sow). The Pig 

 tribe ; a group of pachydermatous ani- 

 mals, having four toes on each foot, and 

 three sorts of teeth in each jaw. 



SULPHAMIDE. A compound ex- 

 actly analogous to oxamide, containing 

 P5 



