MISCELLANY. 
319 
For merly, and even at the time when the Spanish colonies were 
independent, the value of the crop amounted in the district of Misantla 
to no more than 50,000 st. yearly ; in the year 1844, however, it 
yielded two millions ; in 1845, three millions, and a further increase 
of a million may be expected in 1846. Impositions, robberies, &c, 
appear to be very common in the vanilla trade. Schiede, in his 
botanical reports from Mexico, (Linnaea, von Schlechtendahl, vol. iv., 
1829) says, that besides Misantla, the cultivation of vanilla is carried 
on also in Papantla, Nautla, and Colipa. — Pharm Jour., from the Ann. d. 
Sciences. 
Test for Anhydrous Alcohol. By Casoria. — In order to determine 
whether alcohol contains water, let a sample of it stand for some time 
in a well-closed vessel, with anhydrous sulphate of copper. If water be 
present, the latter assumes a blue colour; but it remains white if the 
alcohol be free from water. — Pharm. Journ. 
Production of NobiWs Coloured Rings, from Zinc, by Galvanism. By 
A. A. C. Walter. — A cup having been filled with a concentrated solu- 
tion of chloride of zinc, a platina wire from the zinc pole of a strong 
voltaic battery was dipped into it, and then a silver-plated copper disc, 
fastened to the platina wire of the copper pole, was introduced into it. 
Nobili's coloured rings appeared on the plated surface, which, however, 
soon became dim again. At the same time, foliaceous vegetations of 
glittering metallic zinc precipitated from the wire of the zinc pole, 
which soon extended to the copper plate. The latter having been 
removed, and the wire of the copper plate again introduced, the vege- 
tative formation of zinc soon lost its metallic appearance, and changed 
into a granular mass of a gray colour, which entirely dissolved after a 
short time. — Ibid, from Central Blatt. 
How to distinguish Stains of Blood from other Stains. — Peroz found 
that blood-stains are blackened by hypochlorous acid, while most 
colouring substances are bleached by it. Brame adds, that the hypo- 
chlorous acid should be free from the perchloride of mercury, as it is 
easily obtained by Williamson's method, or by agitating fresh chlorine- 
water with peroxide of mercury. The same author advises removing 
the stains with faintly-alkaline water, and then performing the experi- 
ment in a glass tube. The solution then appears, at a certain degree 
of concentration, red by reflected light and greenish by transmitted light. 
M. Buchner states, that the presence of mercury does not appear to 
interfere in the least with the reaction of the acid, and that the blood- 
stains instantly become brown, but not black. Chloride of lime or 
