BOE 



BOI 



1, 3, 5, &c. The times and velocities are 

 in a subduplicate ratio of the spaces. 

 The velocity of descending bodies is in 

 proportion to the times from the begin- 

 ning of their fall ; and the spaces des- 

 cribed by a falling body are as the 

 squares of the times from ihe beginning 

 of their fall. See MECHANICS. 



BODT, in law. A man is said to be 

 bound or held in body and goods ; that 

 is, he is liable to remain in prison, in de- 

 fault of payment. 



In France, all restraints of the body 

 for civil debts are null after four months, 

 unless the sum exceeds two hundred li- 

 vres. 



A woman, though in other respects she 

 cannot engage her person but to her hus- 

 band, may he taken by the body, when 

 she carries on a separate trade. 



BODT, among painters; as, to bear a 

 body ; a term signifying that the colours 

 are of such u nature, as to be capable of 

 being ground so fine, and mixing with 

 the oil so entirely, as to seem only a very 

 thick oil of the same colour. 



lint such colours as are said not to 

 bear a body will readily part with the 

 oil when laid on the work ; so that when 

 the colour shall be laid on a piece of 

 work, there will be a separation ; the 

 colour in some parts, and the oil in others, 

 except they are tempered extraordinarily 

 thick. 



BOEBEUA, in botany, a genus of the 

 Syngenesia Superflua class and order Re- 

 ceptacle naked ; down simple ; calyx dou- 

 ble, the outer many-leaved, inner eight- 

 leaved. One species, found in Carolina 

 and Mexico. 



BOEHMERIA, in botany ; so called in 

 honour of George Rudolph Boehmer; a 

 genus of the Monoecia Tetranuria class 

 and order. Natural order of Scabridse. 

 Urticae, Jussieu. Essential character : 

 male, calyx four parted; corolla none; 

 female, calyx none, but crowded scales 

 between each ; germ obovate ; style sin- 

 gle ; seed single, compressed. There 

 are five species ; of which B. caudata is 

 a shrub, growing to the height of ten or 

 twelve feet ; the leaves are very broad. 

 It is frequent in the cooler mountains of 

 Liguanea, in Jamaica: B. literalis is a na- 

 tive of Hispaniola: B. cylindrica is an an- 

 nual plant, with a lucid herbaceous stalk, 

 dividing into several branches ; the leaves 

 have three longitudinal veins, and are 

 placed on pretty long foot-stalks ; flowers 

 in single catkins, which are not divided. 

 Native of North America and Jamaica. 



BOERHAV1A, in botany; so called in 

 honour of the famous Boerhaave ; a ge- 



nus of the Monandria Monogynia clasi 

 and order. Natural order of Aggregate ; 

 Nyctagenes, Jussieu. Essential charac- 

 ter: calyx none; corolla one-peialled, 

 bell-shaped, plated ; seed one, naked, in- 

 ferior. There are seven species ; of 

 these B. erecta, upright flag-weed, lias 

 a stem two feet high ; at each joint a 

 pair of ovate-pointed leaves, whitish un- 

 derneath ; on foot stalks an inch in 

 length ; at these joints, which are far 

 asunder, come out also small side branch- 

 es, growing erect ; they, as well as the 

 stem, are terminated by loose panicles 

 of flesh coloured flowers, succeeded by 

 oblong glutinous seeds. This plant is 

 found at La Vera Cruz, also in the Socie- 

 ty isles. 



BOILING. When all other circum- 

 stances are the same, the evaporation of 

 liquids increases with their temperature : 

 and after they are heated to a certain tem- 

 perature, they assume the form of elastic 

 fluids with great rapidity. If the heat be 

 applied to (he bottom of the vessel con- 

 taining the liquids, as is usually the case 

 after the whole liquid has acquired this 

 temperature, those particles of it which 

 are next the bottom become an elastic 

 fluid first : they rise up as they are form- 

 ed, through the liquid, like air bubbles, 

 and throw the whole into violent agitation. 

 The liquid is then said to boil. Every 

 particular liquid has a fixed point at 

 which this boiling commences (other 

 things being the same ;) and this is called 

 the boiling point of the liquid. Thus, 

 water begins to boil when heated to 212. 

 It is remarkable., that after a liquid has 

 begun to boil, it never becomes any hot- 

 ter, however strong the fire be to which 

 it is exposed. A strong heat indeed makes 

 it boil more rapidly, but does not increase 

 its temperature. This was first observ- 

 ed by Dr. Hooke. The following table 

 contains the boiling point of a number of 

 liquids. 



Bodies. Boiling po ; -r. 



Ether 98 



Ammonia 140 



Alcohol 176 



Water 212 



Muriat of lime .... 230 



Nitric acid 248 



Sulphuric acid .... 590 



Phosphorus 554 



Oil of turpentine . . . 560 



Sulphur 570 



Linseed oil 600 



Mercury 660 



It will be seen, when we come to treat 



