SUF 



SUG 



ened to a considerable depth, and 

 root culture is much improved ; the 

 soil is also considerably drained, and, 

 if moor pans exist in it, may be re- 

 claimed I'rom sttjrility. It is there- 

 fore an admirable jjrocess in stitT soils 

 imperfectly drained, but in loose 

 gravelly or sandy soils subsoil plough- 

 ing is often very injurious. I5y the 

 tillage of years, the treading of cat- 

 tle, and the pressure of the sole of 

 the plough and rolling, the surface 

 soil becomes compact, and holds wa- 

 ter and manure sutticiently for the 

 crops ; but by suhsoiling these ad- 

 vantages are thrown away, and a 

 thirsty, loose soil again established. 



SUBSTANTIVE COLOURS. 

 Colouring matters which stain the 

 texture or yarn permanently-, without 

 the necessity for a mordant ; the lat- 

 ter being called adjective colours. 



SUBSTITUTION. In chemistry, 

 the doctrine advanced by Dumas, that, 

 in many organic and complex com- 

 pounds, one element can take the 

 place of another without changing the 

 relations of the others. 



SUBSTRATUM. The stratum of 

 a different geological kind immedi- 

 ately below the surface. 



SUBULATE. Awl-shaped, round, 

 and tapering to the end. 



SUBULICORNS. A family of neu- 

 roptera, with awl-shaped antenns. 



SUBULIPALPS. A section of 

 caraboid beetles, some of which have 

 the exterior palpi awl-shaped. 



SUCCORY. See Chicory. 



SUCCULENT. Fleshy, full of 

 water. 



SUCKERS. The shoots from the 

 roots of trees or plants near the stem. 

 They are often serviceable for prop- 

 agation. 



SUCTION PU.MP. See Pump. 



SUDORIFICS. Medicines which 

 produce increased perspiration. 



SUET. Fat which contains a large 

 proportion of stearin, and is hard. 

 It is best from the loins or kidneys of 

 the sheep, and next from the ox. It 

 is used for the best tallow candles. 



SUFFRUTEX. An under shrub, 

 a small shrub, a portion of whose an- 

 nual stems die away. Suffruticoxe is 

 like an under shrub. 



SUGAR. One of the indifferent 

 and ordinary products of plants. It 

 is recognised by its flavour. Chem- 

 ists distinguish a variety of species 

 of sugar, of which the ciystallizable, 

 or cane sugar, and uncrystallizable, or 

 (UfficuUly crystaUizahle, or grape su- 

 gar (glucose), are the representatives ; 

 these differ in composition, cane su- 

 gar being Cu Hn On, and grape su- 

 gar, C,.; Hi4 Oi., ; but their chief dis- 

 tinction rests in the circumstance that 

 grape sugar is capable of undergoing 

 fermentation, whereas cane sugar 

 must tirst be converted into glucose 

 to ferment. Grape sugar is identical 

 with that from fruits, green stalks, 

 and with diabetic and starch sugar. 

 .Sugar for commercial purposes is ob- 

 tained chiefly from the cane, but the 

 beet is also extensively manufactur- 

 ed (see Bed), and the maple (see Ma- 

 ple) yields a large quantity. Some 

 sugar or molasses is also made from 

 starch of potatoes by boiling it in sil- 

 ver or lead boilers with dilute sulphu- 

 ric acid : for this purpose, 200 parts of 

 starch, 4 of strong acid, and 800 of 

 water are used, and the boiling con- 

 tinued thirty hours : by steaming at a 

 high pressure, six hours will answer. 



SUGAR CANE. Aru>ido saccha- 

 rifera. It is very readily destroyed by 

 light frosts, and cannot be grown 

 north of 32= N. In Louisiana the 

 frost sometimes destroys the crop, 

 and to save it, the cut stems are piled 

 up, or mattressed on the field in mass- 

 es three or four feet high. The press- 

 ing is done between rollers worked 

 usually by animals, but sometimes by 

 wind, water, or steam power. The 

 process of making the sugar is de- 

 tailed under the article Beet. The 

 following short rules may, however, 

 be of service : 



"1. To cut the cane as ripe as pos- 

 sible, but before any acetic acid is 

 formed : litmus paper, touched to the 

 fresh-cut cane, will turn red if acid. 



"2. Express the juice witlioutloss 

 of time, as every moment after cut- 

 ting will deteriorate its quality. 



" 3. A small quantity of clear lime- 

 water, say one quart to a hundred gal- 

 lons of juice, should be added the mo- 



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