BALSAM. 



of resin, and the balsam is obtained by 

 boiling 1 the twigs in water. It has the 

 consistency of honey, a brown colour, an 

 agreeable smell, and a hot acrid taste. 

 When boiled with water for some time, 

 the liquid separated by the filter reddens 

 vegetable blues, and deposits crystals of 

 benzole acid on cooling. The water con- 

 tains no other substance. When distilled 

 with water, it yields a very small quantity 

 of reddish limpid oil. A saturated solu- 

 tion of carbonate of soda forms with this 

 balsam a thick mass. When diluted with 

 water, and heated, a portion is dissolved. 

 The solution, when saturated with sul- 

 phuric acid, deposits crystals of benzoic 

 acid. One part of the balsam, treated 

 with one part of potash dissolved in four 

 parts of water, formed an opaque solu- 

 tion, which gradually separated into two 

 portions : the uppermost, a clear oil, with 

 some grey flakes at its lower surface ; 

 the undermost, a dark brownish red 

 opaque solution. This last solution, when 

 saturated with sulphuric acid, let fall a 

 resinous-like substance, dissolved by boil- 

 ing, while benzoic acid crystallized. Ni- 

 tric acid acts upon the balsam with ener- 

 gy, and gives it an orange yellow colour, 

 when assisted by heat. When distilled 

 with a sufficient quantity of this acid di- 

 luted, the liquid in the receiver smells of 

 bitter almonds. When this balsam is 

 treated with sulphuric acid, artificial tan- 

 nin is also' formed, and the residual char- 

 coal amounts to no less than 0.64 of the 

 original weight of the balsam. 



5. Styrax. This is a semifluid juice, 

 said to be obtained from the Styrace ofK- 

 cinale, a tree which grows in* Virginia, 

 Mexico, andsome other parts of America. 

 It is prepared in the island Cobrass, in 

 the Red Sea, from the bark of a tree call- 

 ed rosa mallos by the natives, and consi- 

 dered by botanists as the same with the 

 American species. The bark of this tree 

 is boiled in salt water to the consistence 

 of bird-lime, and then put into casks. 

 Bouillon la Grange has published an ac- 

 count of its properties. Its colour is 

 greenish, its taste aromatic, and its smell 

 agreeable. It is easily volatilized by heat. 

 When treated with water, benzoic acid 

 is dissolved. It is totally soluble in alco- 

 hol, except the impurities. When ex- 

 posed to the air, it becomes harder, and 

 absorbs oxygen. When distilled, it yields 

 an acidulous water, having the odour of 

 benzoic acid, a limpid colourless hot oil, 

 a solid coloured oil, benzoic acid, and a 

 mixture of carbonic acid and carburetted 



hydrogen. The charcoal is light, and con- 

 tains some oil. 



Solid balsams. The solid balsams at. 

 present known are only three in number ; 

 namely, 



1. Benzoin. 3. Dragon's blood, 



2. Storax. 



1. Benzoin. This substance is the pro- 

 duce of the styrax benzoe, a tree which 

 grows in Sumatra, &c. and which has been 

 described by Dr. Dryander. Benzoin is 

 obtained from this tree by incision ; a tree 

 yielding three or four pounds. It is a 

 solid, brittle substance, sometimes in the 

 form of yellowish white tears, joined to- 

 gether by a brown substance, and some- 

 times in'the form of a brown substance, 

 not unlike common rosin. It has a very 

 agreeable smell, which is increased by 

 heating the benzoin. It has little taste. 

 Its specific gravity is 1.092. Alcohol dis- 

 solves it when assisted by a gentle heat, 

 and forms a deep yellow solution, inclin- 

 ing to reddish brown. When this solu- 

 tion is diluted with water, the benzoin 

 precipitates in the form of a white pow- 

 der. It is precipitated also by muriatic 

 and acetic acids, but not by the alkalies. 

 A few drops of sulphuric acid likewise 

 precipitate the benzoin ; but an additional 

 quantity re-dissolves it, and forms a li- 

 quid, of the colour of port wine. Nitric 

 acid acts with violence on benzoin, and 

 converts it into an orange-coloured mass. 

 When assisted by heat, the acid dissolves 

 the benzoin; and as the solution cools, 

 crystals of benzoic acid gradually sepa-" 

 rate. Mr. Hatchett ascertained, that by 

 this process a quantity of artificial tannin 

 is formed. Sulphuric acid dissolves ben- 

 zoin, while benzoic acid sublimes ; the 

 solution is at first a deep red. By conti- 

 nuing the digestion, a portion of artificial 

 tannin is formed, and the charcoal evolv- 

 ed amounts to 0.48 of the benzoin dis- 

 solved. Acetic acid dissolves benzoin 

 without the assistance of heat. When 

 heat is applied, the solution, as it cools, 

 becomes turbid; owing to the separation 

 of benzoic acid. Benzoin is dissolved by 

 a boiling lixivium of the fixed alkalies.; 

 a dark brown solution is formed, which 

 becomes turbid after some days exposure 

 to the air. Ammonia likewise dissolves 

 benzoin sparingly. 



2. Storax. This is the most fragant 

 of all the balsams, and is obtained from 

 the styrax ofiicinalis, a tree which grows 

 in the Levant, and it is said also in Italy. 

 Sometimes it is in the state of red tears : 

 and this is said to be the state in which 







