236 
MISCELLANY. 
prepared in the spring were all brown, of the peculiar odour and bitter 
saline taste ; the extracts prepared in the autumn were, on the contrary 
yellowish-brown, and possessed a sweetish odour and taste. On solu- 
tion in water, the extracts prepared in spring deposited much less inu- 
line than those made in autumn. The extract obtained by pressure is 
most active, but it is also the dearest; the infusion, over which the de- 
coction has no advantage, is preferred. Perhaps it would be best first 
to express the plant, then to infuse the residue in a little hot water for a 
few hours, to express again ind proceed as usual. — Ibid, from Archiv der 
Pharm. 
Heusler^s Charta Vesicatoria. — Yellow wax, §iss; oil of cantharides, 
; spermaceti, gvj ; larch turpentine, §ij, are melted together, and the 
mass when nearly cold is spread upon paper with a spatula. The fol- 
lowing plaster, likewise spread on paper, is recommended for confining 
it to the intended place: — Lead plaster, ^vj ; purified rosin, yellow wax' 
olive oil, of each £>ij ; turpentine, gv. Mix. — The Chemist, Jahrb. filr 
Prakt. Pharm. 
Observations on Balsam, Copaiva. By. J. E. Simon. — The genuine- 
ness of copaiva balsam is frequently tested by'mixing 3 parts of balsam 
with one of caustic ammonia of 0-96 spec. grav. If the mixture is ren- 
dered clear by shaking, the balsam is usually considered genuine. If 
to this balsam the sixth part of oil of juniper-wood be added, it behaves 
towards ammonia precisely like the genuine, likewise affording a clear 
combination, which proves the insufficiency of this test. 
Of late there has frequently occurred in commerce a balsam which 
will not bear the above test with ammonia. I have taken much trouble 
to detect any adulteration in this balsam, but am thoroughly convinced 
that it is perfectly genuine. It contains from 20 to 25 per cent, more 
essential oil, which renders it more liquid, but the oils from both kinds 
of balsam are identical in odour and in all other properties ; the residu- 
ous resin in both kinds becomes equally hard and brittle, which entirely 
does away with the supposition of its having been adulterated with any 
fat oil. The two resins however differ, the one affording a soapy com- 
bination with caustic alkalies, which the resin of the new balsam does 
not. 
Whether this new balsam is obtained from younger trees, or whether 
it is derived from a different species ; whether the one is more active 
than the other, it is impossible for me to say ; but the latter is decided- 
ly not adulterated, for on boiling with water not the least foreign odour is 
perceptible, and the residue, after boiling and driving off the volatile oil, 
is hard and brittle like sealing wax. — Chem, from Archiv. der Pharm. 
