Chemical Science. 385 
when boiled becomes turbid, and deposits more oxide. Although the 
quantity of water is mentioned above, yet the decomposition takes 
place with other proportions, but most rapidly when the proportion is 
greatest ; 100 parts. of verdigris were found to leave about 23 parts 
of oxide of copper. In order to ascertain the correctness of an 
Opinion, that it was the sub-acetate only in the verdigris which 
underwent this change, some of that salt was prepared, and one part 
mixed with 500 of water, and agitated from time to time. At first 
the salt swelled and became flocculent, then it became yellow, and at 
Jast brown, diminishing rapidly in volume. These effects were more 
rapid in the sun’s rays, without doubt from the heat produced. The 
per-oxide, when collected gave 46 per cent. of the sub-acetate em- 
ployed, just double that afforded when verdigris was used, and the 
soluble crystallized acetate of copper formed remained in the solution, 
as.was proved by boiling the solution ; it underwent a further de- 
composition, just as the crystalline acetate had done before. 
“ Thus,” says M. Vauquelin, “ there are three combinations of the 
oxide of copper and acetic acid: Ist, a sub-acetate insoluble in 
water, but decomposing in that fluid, at common temperatures be- 
coming per-oxide, and an acetate ; 2nd, a neutral acetate, the solution 
of which is not altered at common temperatures, but is decomposed 
by ebullition, changing into per-oxide, and a super-acetate ; 3rd, a 
super-acetate, which, when in solution is not decomposed, cither at 
common temperatures, or at the point of ebullition, and which cannot 
be obtained crystallized, except by slaw spontaneous evaporation, or 
evaporation in a vacuum.” . 
22. Duhline or Inuline in the Jerusalem Artichoke.-—M. Braconnot, 
whilst engaged lately in an examination of the tubercles of the Heli- 
antk.as Tuberosus, or Jerusalem Artichoke, ascertained the presence 
of a substance in them, in all respects resembling the Dahline of 
M. Payen. The recent tubercles were rasped, pressed, and the 
juice collected; left to itself it deposited a substance like starch, 
which, when collected and boiled in water, was almost entirely dis- 
solved; but on evaporation a substance was deposited like the 
Dahline. (See vo}. xvi. p. 387.) M. Braconnot, however, does not 
think that this, or M. Payen’s substance should be considered as a 
new proximate principle, but considers them both as specimens of 
Inuline.—Ann. de Chim. xxv. 361. 
23. New Vegeto-alkalies.—Violine.—At a sitting of the Académie 
Royale de Médicine, M. Boullay read a memoir on the analysis of 
the violet, viola odorata, from which it appears that the violet contains 
an active alkaline, bitter and acrid principle, similar to the Emetine 
of Ipecacuanha, and which is called by the author, Emetine of the 
violet, indigenous emetine, or violine, According to M. Ortfila it 
