22 



Aveilill. Peculiar protein substance of oats (A vena sativa). 

 To prepare it, grind the grains with water, dikite the pasty mass 

 Avith water, strain after twelve hours, filter the liquid, precipitate 

 ■with acetic acid, dissolve the precipitate in diluted liquor of 

 ammonia, precipitate again with acetic acid and purify the preci- 

 pitate by means of alcohol and ether. The Avenin is gi-eyish-white, 

 dissolves readily in water, does not coagulate by heat, dissolves 

 also in an excess of acetic and hydrochloric acids. 



Azilleil=Ci6 Hi2 + HO. Ingredient of volatile oils and 

 causes the blue and the brown oi- yellow-green colour of them, in 

 the latter cases when mixed with a yellow resin. It distils with 

 difficulty and can be obtained in the pure state by repeated 

 fractional distillations and rectification. It boils constantly at 

 302°, has a density of 0-910; its vapour is also of blue colour. 

 In the blue oil of chamomil there is scarcely 1 per cent, of 

 Azulen ; the patchouly oil (from Pogostemon Patchouly) with 6 

 per cent, and the wormwood oil with 3 per cent. Azulen are not 

 of a blue colour, because they contain a comparatively large 

 quantity of yellow resin. 



BillSiiniS. Natural combinations of resins with volatile oils> 

 viscid or fluid at ordinaiy temperatures, becoming thicker and 

 and often solid by age. 



Balsam of Coi)aiva=CopAivA Balsam. 



Balsam of Mace = Mace Balsam. 



Balsam of Mecca= Mecca Balsam. 



Balsam of ]Vutmeg'= Nutmeg Balsam. 



Balsam of Perils Peru Balsam. 



[Balsam of Siiulor. Three varieties have been examined, two 

 of which are the exudations of the stem of Sindora species, the 

 third probably originating from a kind of Dipterocarpus. The 

 latter balsam is light-brown, thickish, of the odour of Copaiva 

 balsam, and of 0-9221 density at 27-5°. By distillation with 

 water it yields a beautiful red-brown, transliTcid resin, and a 

 volatile oil of light-yellow colour, thin fluidity and 0-914 spec, gv., 

 boiling at 246° to 255°, soluble in 4 to 5 parts cold, and 1 to 1^ 

 parts warm alcohol, of acid properties. The two other kinds 

 of balsam are distinguished from the first by not yielding 

 up their volatile oil to the vapours of water. The volatile 

 oils, obtained by heating the balsams to about 255°, are 

 of a yellowish or greenish-yellow colour, 0*904-907 spec, gr. 

 and soluble in alcohol. The resin was in one case brittle, yellow- 

 brown, soluble in alcohol, chloroform, ether and oil of turpentine, 

 producing with alcohol a brilliant varnish on glass; in the other 



