BENZOLE 337 



a very raro article of comracrco. An attempt has been mado in Jamaica, by Mr. 

 Komblo, to raise the moringa for the sake of this oil, but the samples there produced 

 remained a perfectly solid fat in England throughout the whole year. S.P. 



BEN'ZIDIN'E. An alkali, discovered by Zinin, in acting with reducing agents 

 on arzobonzide and azoxibenzidc. C.G.W. 



BENZ,n\TE. See BEXZOLE. 



HEM-ZOIC ACIU. C U H"0 4 (C 7 H 6 O=). This acid may be obtained by placing 

 benzoin powdered, with sand, in an evaporating basin, and above it a paper cap ; on 

 applying heat carefully to the sand, acid vapours arise from the resin, and they are 

 deposited in the form of fine light crystals within the paper cap. Stolze recommends 

 the following process for extracting the acid : The resin is to bo dissolved in three 

 parts of alcohol, the solution is to bo introduced into a retort, and a solution of car- 

 bonate of soda dissolved in dilute alcohol is to bo gradually added to it, till the free 

 acid be neutralised ; and then a bulk of water equal to double the weight of the benzoin 

 is to be poured in. The alcohol being drawn off by distillation, the remaining liquor 

 contains the acid, and the resin floating upon it may be skimmed off and washed, when 

 its weight will be found to amount to about 80 per cent, of the raw material. 



Benzoic acid is also obtained by boiling hippuric acid, or the urine of cows or 

 horses which contains this acid, with hydrochloric acid. 



BENZOXXT, or BENJA-TVnw. (Benjoin, Fr. ; Benzbe, Ger.) A species of resin, 

 used chiefly in perfumery; improperly called a gum, since it is quite insoluble in 

 water. It is extracted by incision from the trunk and branches of the Styrax benzoin, 

 or Lilhocarpus benzoin, which grows in Java, Sumatra, Santa Fe, and in the kingdom 

 of Siam. The plant belongs to the natural family of the Styracac&e. The benzoin 

 flows in small quantities spontaneously from the trees ; but it is collected by making 

 incisions in the stem, just below where the branches are given off, as soon as the tree 

 has attained an ago of five or six years. These incisions are repeated each year 

 for about twelve years, when the tree becomes exhausted. The resin flows out as 

 a white fluid. It hardens readily in the air, and comes to us in brittle masses, whoso 

 fracture presents a mixture of red, brown, and white grains of various sizes, which, 

 when white, and of a certain shape, have been called amygdaloid, from their resem- 

 blance to almonds. The benzoe in sortis is very impure, containing portions of wood 

 and bark. 



The fracture of benzoin is conchoidal, and its lustre greasy ; its specific gravity 

 varies from T063 to 1'092. It has an agreeable smell, somewhat like vanilla, which 

 is most manifest when it is ground. It enters into fusion at a gentle heat, and then 

 exhales a white smoke, which may bo condensed into the acicular crystals of benzoic 

 acid, of which it contains 18 parts in the hundred. Ether does not dissolve benzoin 

 completely. The fat and volatile oils dissolve very little of it. 



Unverdorben has found in benzoin, besides benzoic acid and a little volatile oil, no 

 less than three different kinds of resin, none of which has, however, been turned, as 

 yet, to any use in the arts. 



Benzoin is principally used in perfumery ; it enters into a number of preparations, 

 among which may bo mentioned fumigating pastilles, fumigating cloves (called also 

 nails), poudre a la marechale, &c. The alcoholic tincture, mixed with 20 parts of 

 rose-water, forms the cosmetic virginal milk. Benzoin enters also into the composi- 

 tion of certain varnishes employed for snuff-boxes and walking-sticks, in order to 

 give these objects an agreeable smell when they become heated in the hand. It is 

 added to the spirituous solution of isinglass, with which court-plaster is made. 



BEXrzo&E. Syn. Benzine, benzene, benzol, hydruret of phenyl, C 12 H 6 (C S H 6 ). 

 A compound of carbon and hydrogen discovered by Faraday in the products of the 

 destructive distillation of whale-oil. The more volatile portion of coal-naphtha has 

 been shown by Mansfield to consist chiefly of this substance. It is produced in a 

 great number of reactions in which organic bodies are exposed to high temperatures. 

 It may at once be obtained in a state of purity by distilling benzoic acid with excess 

 of quicklime. The lime acts by removing two atoms of carbonic acid from the 

 benyxnc acid. The method of obtaining benzole from coal-naphtha will bo found fully 

 described under the head of NAPHTHA, COAL. Benzole is also contained in considerable 

 quantity in bone-oil ; but it is accompanied by peculiar nitrogenised volatile fluids, 

 which are difficult of removal. The latter, owing to their powerful and fetid odour, 

 greatly injure the quality of the bone-oil benzole. Benzole is an exceedingly volatile 

 fluid, boiling at ordinary pressures at 187 F. Its density is 0'850. Owing to the 

 levity of benzole being regarded by manufacturers as a proof of its purity, it is not 

 uncommon to find it adulterated with the naphtha from the Torbanehill mineral, or 

 Boghead coal, which has a density as low as 0750. Any benzole having a lower 

 density than 0'850 is impure. Benzole is excessively inflammable, and its vapour 

 mixed with air is explosive. Numerous lives have been lost owing to these properties, 



VOL. I. Z 



