DEFINITION OF TERMS. 



59 



the solution, and the sulphur will be pre- 

 cipitated. The solution, which consists 

 of nitic acid combined with barytes, is to 

 be filtered and evaporated slowly till it 

 crystalHzes. Put the crystal into a cruci- 

 ble, and expose it to a strong heat; the 

 nitric acid is driven off, and the barytes 

 remains in its purity. 



Jinother uiet/iod pointed out by Dr. 

 Hope. Decompose the sulphate of barytes, 

 by heating it strongly along with charcoal 

 powder. The product is to be treated 

 with water to dissolve every thing that is 

 soluble, and the liquid being filtered, is 

 to be mixed with a solution of carbonate of 

 soda. A white powder falls. Wash this 

 powder; make it up into balls with char- 

 coal, and heat it strongly in a crucible. 

 When these balls are treated with boiling 

 water a portion of barytes is dissolved, 

 which crystallises as the water cools. It 

 is a grayish white porous body, which 

 may very easily be reduced to powder. It 

 has a harsh and more caustic taste than 

 lime, and when taken into the stomach 

 proves a most violent poison. 



Belles-Lettres, a word absurdly intro- 

 duced from the French. The French 

 writers themselves have no determinate 

 idea affixed to this phrase; som'e applying 

 it to polite literature only, and some ex- 

 tending it to the whole scope of human 

 learning, even to the mathematics. 



Beta, a genus of the pentandria digy- 

 nia class and order of plants; and in the 

 natural method ranking under the 12th 

 order, holoraceae. The calyx has five 

 leaves; there is no corolla; the seeds are 

 kidney shaped, and situated within the 

 base of the calyx. There are four species, 

 vizi 1st, Beta cicla the root of scarcity. 

 The Beta hortensis, or common white beet, 

 is a variety of this; 2d, the Beta maritima, 

 the sea beet: 3d, Beta apatula, a native of 

 Madeira; 4th, Beta vulgaris, the red beet 

 with a pyramidal root, has large thick 

 succulent leaves, which are for the most 

 part of a dark green or purple color, the 

 roots are large and of a deep red, the larg- 

 er these roots grow, the more tender they 

 are, and the deeper the color, the more 

 they are esteemed; the varieties of this 

 species are the common red beet, the tur- 

 nip rooted beet, and the green leaved red 

 beet. On many parts of the continent of 

 Europe, the beet root has been used for 



the purpose of extracting sugar from it, 

 (see pages 5, 6, 20, 36, which relate to 

 beets and sugar). According to Achard, 

 the quantity of beet in Prussia that will 

 yield one pound of sugar is twenty pounds; 

 one hundred pounds of raw sugar give 

 fifty five of refined, and twenty five 

 pounds of molasses. It is computed by 

 the same gentleman, who has employed 

 much time in the pursuit, that a German 

 square mile of land, that is, sixteen square 

 miles English, properly cultivated, would 

 produce white beet sufficient to furnish 

 the whole Prussian dominions with sugar. 



Bice or Bise, among painters, a blue 

 colour prepared from the Lapis Armenus. 



Bice bears the best body of all bright 

 blues used in common work, as house 

 painting, &c. but it is the palest in color. 

 It works indifferently well, but inclines a 

 little to sandy, and therefore requires good 

 grinding. Next to ultramarine, which is 

 too dear to be used in common work it 

 lies best near the eye of all other blues. 



Boiling or ebullition, in Physics, the 

 agitation of a fluid body, arising from the 

 application of fire, &c. The following 

 table shows the boiling point of several 

 iquids. 



The boiling point however is found io 

 depend upon the degree of pressure to 

 which the liquid is exposed. In a vacuum, 

 all liquids are said to boil at 145 degrees 

 lower than in the open air under a pres- 

 sure of 30 inches of mercury; therefore 

 water would boil in vacuo, at 67 degrees, 

 and alcohol at 34 degrees. In Papin's di- 

 gester, the temperature of water may be 

 raised to 300 degrees, or even 400 de- 

 grees without ebullition; but the instant 

 that this great pressure is removed, the 

 boiling commences with prodigious vio- 

 lence. 



