27 



ßetuliu^Cso H40 O4. In the epidermis of the bark of 

 Betula alba. Exhaust the dry bark first with boiling water and, 

 after it has been dried again, with boiling alcohol and filter while 

 hot; when cold the B. separates and has to be recrystallised in 

 ether. Voluminous white flocks or warty masses, without smell 

 or taste; fuses at 200° with an odour of heated birch-bark; may be 

 sublimated in a current of air; insoluble in water; dissolves hx 

 120 parts cold and in 80 parts hot alcohol, also in ether, oils and 

 alkalies and precipitable from the latter by acids; soluble in con- 

 centrated sulphuric acid and precipitable by water, 



Betuloretic Acid =072 Heo Oio. Covers as a white resin the 

 young shoots and the upjjer siirface of the young leaves of 

 Betula alba, and is obtained by removing it mechanically. It has 

 to be jJurified by dissolving in hot alcohol ; evaporating ; dissolving 

 in ethei-, which leaves behind a black substance; evaporating; dis- 

 solving the residue by solution of carbonate of soda, and prtci- 

 jiitating by an acid. White flakes or white friable mass softening 

 in the mouth, fusing at 94°, in alcoholic solution of very bitter 

 taste and acid reaction; dissolves also in ether and alkalies, and 

 with beautiful red colour in concentrated sulphuric acid. 



Bicaliyba Fat, from Myristica Bicahyba, similar to Nutmeg 

 balsam. 



Bircli-Stearoi)teii=BETULiN. 



Bolieic Aci(l = Cu Hg Oio + 2H0. Found as yet only in 

 small quantities in the black tea (from Tliea Chinensis), besides 

 much iron-bluing tannic acid. The aqueous extract of tea is pre- 

 cipitated by acetate of lead; filtered; the filtrate (containing 

 acetate of lead) saturated by ammonia, the yellow precipitate 

 collected, washed, mixed with absolute alcohol, pervaded with 

 sidphuret of hydrogen ; filtered, and the filtrate evaporated in a 

 vacuum. Pale yellow, very hygroscopic substance, similar to 

 gallo-tannic acid; fuses at 100°; dissolves in every amount in water 

 and alcohol; the solution imparts a brown colour to chloride of 

 iron without precipitating it. 



Boletic Aci(l=FuMARic Acid. 



Boi'liecll=:C2o H16. Constitutes (contaminated with a little 

 resin) the camphoric oil of Dryobalanops Camphora, and forms the 

 non-oxygenised constituent of the oil of Valeriana. The portion 

 of the latter oil which, in rectifying, distils first, has to be distilled 

 again with recently-melted caustic potash, whereby valerol remains 

 as valerate of potash and borneol and Borneen distil over, from 

 which all borneol may be separated by repeated fractional distil- 

 lations, retaining only the first distilling portions. The Borneen 

 is a colourless oil of turpentine-like odoui", lighter than water ; 

 boils at 160°. 



