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material above named, taken from a locality where it had accumulated to a 
layer of 3 inches’ thickness. This substance does not contain any trace ot 
urea, nor any uric or oxalic acids ; the bulk is made up of the undigested 
horny mass of the wings of insects. Dried at 100°, this substance gave 
8*25 per cent, of nitrogen, and left, after ignition, 6*25 per cent, of ash, con- 
taining potassa, soda, lime, magnesia, oxide of iron, chlorine, sulphuric, 
silicic, and phosphoric acids, the latter being 36 per cent, of the weight of 
the ash. 
The Crystalline Substance covering the Vanilla Pod. — M. P. Carles has 
contributed an article to an early number of the u Journal de Pharmacie ” on 
this subject. The article treats on the nature of the crystalline substance 
which may frequently be seen on the vanilla pods, and have been considered 
by various authors to consist of benzoic or cinnamic acid, or coumarine. The 
author finds that this crystalline matter fuses at about 81° ; boils, with 
partial decomposition, at 280° ; is very readily soluble in alcohol, ether, 
chloroform, and sulphide of carbon ; difficultly soluble in cold water ; 
exhibits a strong acid reaction to blue litmus paper ; and decomposes car- 
bonates. Elementary organic composition, C 16 H 8 0 6 . The author has pre- 
pared several salts of this acid \ but, as to its true chemical composition, his 
labours are not yet completed. See also <e Chemical News.” 
Ozone. — At the meeting of the Chemical Society on June 1, Dr. Debus, 
F.B.S., delivered a lecture on the subject of ozone. The lecturer began 
by stating why ozone is considered to be an allotropic modification of 
oxygen ; then discussed whether there are reasons to assume the exist- 
ence of two allotropic modifications, and concluded with a review of some 
of the properties of ozone. 
Himalaya Tea. — In the “ Annalen der Chemie ” for May we find a paper 
by Dr. P. Zoller. This paper contains the results of a series of experiments 
made with a sample of very fine tea, a small quantity of which had been 
sent to Professor J. Yon Liebig by a proprietor of tea plantations. 
100 parts of the tea contained 4-25 of water and 5-93 of ash, which, in 
100 parts, was found to consist of — potassa, 39 22 ; soda, 0*65 j mag- 
nesia, 6-47 ; lime, 4-24 ; peroxide of iron, 4-38; manganoso-manganic oxide, 
1*03 ; phosphoric acid, 14-55 ; sulphuric acid, a trace ; chlorine, 0-81 $ 
silica, 4-35 ; carbonic acid, 24-30. Extract soluble in water of this tea 
amounted to 36-26 per cent. The nitrogen in the air-dried tea was found 
to be 5-38 per cent. In addition to 4-94 per cent, of theine, this tea was 
found to contain some theobromine. The quantity of nitrogen in the extract 
(that is, the portion of the tea soluble in water by infusion), dried at 100°, 
is 10-09 per cent., while the ash therein amounts to 11-46 per cent. The 
author concludes by stating that this tea is equal to the best Chinese tea, 
and that the younger the leaves of the shrub the better the tea they yield. 
Formation of Transparent Cubes of Chloride of Sodium similar to Rock- 
Salt. — The u Chemical News ” gives in its usual list of abstracts one, of a 
paper by Dr. Buchner in the “ Journal fur prakt. Chemie” (No. 6, 1871), on 
the above subject. This paper is, in a measure, the reproduction of the con- 
tents of 'an essay published by Dr. Mohr (Poggendorff’s “Annalen,” 
vol. cxxxv., p. 667, 1868), “On the Formation of Bock-salt.” The 
author relates, in confirmation of the facts adduced by Dr. Mohr, a few 
