724 . 
THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. 
[March 9,1872. 
chrysophanine that it contains, turns the plane of 
polarized light to the right. It may be so isolated 
by adding subacetate of lead, separating the precipi¬ 
tate, removing excess of the reagent by sulphuretted 
hydrogen, and evaporating to dryness. The residue 
will consist of glucose, with a small quantity of a 
bitter principle, which is, without doubt, one of the 
original glucosides. 
3. Chrysophanine may be obtained from cathar- 
tine by removing the clirysoplianic acid with ether, 
and destroying the sugar by fermentation. It is 
preferable, however, after the removal of the acid, to 
precipitate the chrysophanine by subacetate of lead, 
and afterwards recover it by decomposing the com¬ 
pound with sulphuretted hydrogen. The chrysopha- 
nine so obtained is, however, but a small proportion 
of what is contained in the senna. To obtain it in 
any quantity, a concentrated infusion should be pre¬ 
pared from at least a kilogram of senna leaves, the 
mucilaginous matter carefully separated by alcohol, 
and the limpid solution precipitated by neutral ace¬ 
tate of lead, the excess of lead carried off by sulphu¬ 
retted hydrogen, and the solution evaporated to a 
syrupy consistence. The product must then be 
treated with 1)0° alcohol, and the residue, insoluble 
in that vehicle, will contain the chrysophanine. 
This residue is purified by dissolving in water and 
preciptating by concentrated alcohol, until the alco¬ 
hol remains uncoloured. It must be dried over sul¬ 
phuric acid, and not by a fire or even a water-bath. 
So prepared, the chrysophanine is white, although 
with clirysoplianic acid it constitutes the colouring 
principle of the preparations of senna. M. Bour- 
goin promises to make known its properties in a 
future memoir. 
Cjpptm for Statols. 
CHEMICAL NOTES TO THE PHARMACOPOEIA. 
BY WILLIAM A. TILDEN, D.SC. LOND. 
DEMONSTRATOR OF PRACTICAL CHEMISTRY TO THE 
PHARMACEUTICAL SOCIETY. 
Pyroxylin. Gun Cotton.—Equal volumes of sul¬ 
phuric and nitric acids (B. P. strength) are mixed 
and allowed to cool. The cotton to be operated 
upon is immersed, thoroughly wetted and left for 
three minutes, then transferred to a vessel of water 
and thoroughly washed. Finally, it is drained and 
dried. 
The cotton, by this treatment, undergoes no change 
of appearance, though under the microscope the fibres 
appear to have shrunk. It will be found to have 
increased in weight. It has, in fact, exchanged two 
atoms of hydrogen for two atoms of N 0 2 , a double 
decomposition having occurred, which is quite ana¬ 
logous to the production of a nitrate by the action of 
nitric acid on a metallic hydrate. E. y .:— 
K ) 
Hi 
Potassic 
Hydrate. 
And— 
0 + 
NO 
H 
2 J 0 
H ydric 
Nitrate. 
K 
NO, 
J 
Potassic 
Nitrate. 
O + 
H) 
h! 
0 
Hydric Hydrate 
or Water. 
(C e H 7 0 2 )) 0 
H 3 (° 3 
Cellulose. 
_ (C 6 H 7 0 2 )) 0 
- H (N 0 2 ) 2 / * 
Dinitro-cellulose. 
+ 2 
[g°0o] 
Nitric Acid. 
+ 2 [g} 0 ] 
W ater. 
If nitric acid more concentrated than that of the 
Pharmacopoeia is employed, and the immersion of the 
cotton prolonged, the third atom of hydrogen is also 
extracted, and a third atom of N 0 2 introduced in its 
place. In this way a body more explosive is pro¬ 
duced, but one which, being insoluble in a mixture 
of ether and alcohol, is unsuited to the production of 
collodion. On the other hand, if the nitric acid em¬ 
ployed has been too weak, a smaller amount of hy¬ 
drogen undergoes replacement, and the cotton is 
less explosible and also less soluble. It is important 
in these experiments to wet the cotton thoroughly 
and uniformly , otherwise the product does not con¬ 
form to the Pharmacopoeia test, and leaves, when 
burnt, a residue of carbon. The hydrogen of cel¬ 
lulose is replaceable by other acid radicles. Thus, 
compounds may be formed in which one, two, or 
three atoms of acetyl (C 2 H 3 O) may be substituted 
for one, two, or three atoms of hydrogen. These 
substitution products are evidently analogous to 
compound ethers ; they are, in fact, salts. We 
may compare them, for instance, to the derivatives 
of ordinary alcohol, the difference being simply in 
the amount of hydrogen replaceable. In ordinary 
alcohol there is but one moveable atom of this kind. 
C 2 H 6 0 
Alcohol. 
C 2 H 5 (N0 2 )0 
Nitric Ether or 
Nitrate of Ethyl. 
C 2 H 5 (C 2 H 3 0)0 
Acetic Ether or 
Acetate of Ethyl. 
The simplest possible formula for cellulose has 
been employed in the foregoing remarks; there can 
be little doubt, however, that the molecular weight 
of this compound is expressed more correctly by 
some multiple of C 6 H 10 O 5 , probably by at least 
Ci 8 H 30 Oi 5 . As a general rule, non-volatility, inso¬ 
lubility and want of crystalline character are indica¬ 
tive of high formulas. Dextrin, bussorin, starch, inulin 
and some other substances present the same compo¬ 
sition as cellulose; though, from the differences in 
their properties, they must be represented by for¬ 
mulas expressive of different degrees of complexity. 
C c H 10 O 5 
Cellulose. 
C 6 H 9 (N0 2 )0 5 
Monouitroceliulose. 
C f) H s (N 0 2 ) 2 0 5 
.Dinitroeellulose. 
C 6 H 7 (N0 2 ) 3 0 5 
Trimtrocelluiose. 
C 6 H 9 (C 2 H 3 0)0 5 
Monucety 1-cellulose. 
CORRESPONDENCE RELATIVE TO CINCHONA 
CULTIVATION IN INDIA. 
Letter from the Secretary of State to 
J. Eliot Howard, Esq. 
“ India Office, January 6th, 1872. 
“ Sir,—I am directed by the Secretary of State for 
India to transmit to you a copy of a report on the 
examination of cinchona barks by Mr. Broughton, dated 
July 31st, 1871, and to request that you will favour his 
Grace with any remarks that may occur to you respect¬ 
ing any of the points upon which Mr. Broughton touches, 
and especially upon the species which is likely to pro¬ 
duce the most remunerative bark for sale in the London 
market. 
“ I am, etc., 
“ (Signed) H. Merivale. 
“ J. E. Howard, Esq.’' 
\Ileply to he sent to the Under Secretary .] 
