404 
THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. [November is, 1871. 
plains of New Caledonia by the natives, who use it 
medicinally, and who believe it to impart a pleasant 
taste to the yam roots, together with which it is 
grown. The plant is closely allied to Andropogon 
citriodorus, from which the lemon-grass oil is ob¬ 
tained. 
Melaleuca viridijlora, Goertn., which is named 
niaouli, is no doubt the most interesting product of 
New Caledonia; the tree is found very frequently, 
but mostly isolated from other trees. The natives 
utilize the thin cork layers of the bark for technical 
purposes ; the leaves serve the soldiers and colonists 
as a spice. The last yield on distillation a colourless 
or yellow, very aromatic oil, similar to oil of cajeput, 
of a sweet and piquant taste, soluble in water, but 
more so in alcohol.— Journ. de Pliarm. et de Chim., 
March, 1870, p. 242. 
THE ACTION OF HYDROGEN UPON NITRIC ACID. 
BY E. BOURGOIN.* 
As the result of a series of electrolytic researches pre¬ 
viously published, the author has shown that there is 
satisfactory ground for assuming that when nitric acid 
is diluted with a considerable quantity of water a hy¬ 
drate of the formula N 2 0 5 , 4 H 2 0 is produced; notwith¬ 
standing- that H. St. Claire Deville, from an examination 
of the action of zinc upon nitric acid, has assigned to the 
same body the formula N 2 0 5 .2H 2 0. When this acid, 
in different degrees of concentration, is submitted to the 
action of the electric current, it is supposed to undergo 
decomposition in the following manner :— 
N 2 0 5 .4H 2 0 = (N 2 0 5 + 0 4 ) + 4 H 2 ; 
oxygen gas alone being evolved at the positive pole, 
while the acid steadily concentrates at the same point. At 
the negative pole hydrogen is set at liberty, but this gas, 
finding itself at the moment of liberation in presence of 
a certain amount of nitric acid, reacts upon the latter, 
with results varying according to the concentration of 
the acid. The examination of this latter action is more 
especially the subject of the present paper. 
I. When a very dilute solution, previously freed by 
boiling from dissolved oxygen, is submitted to electro¬ 
lysis, pure hydrogen alone is evolved at the negative 
pole; the nitric acid during the whole period of the ex¬ 
periment not being sensibly affected by the nascent gas. 
The analytical results confirm this assertion. 
II. When the solution is less dilute, corresponding 
nearly to the formula N 2 0 5 .2H 2 0 -f~ 12 - 5 Aq., the hy¬ 
drogen evolved, at first pure, soon contains a small quan¬ 
tity of nitrogen, and towards the termination of the ex¬ 
periment, ammonia may be detected in the decomposing 
cell. 
III. With a solution one-fourth of the preceding 
strength, N 2 0 5 .2H 2 0, 38 Aq., hydrogen only can be 
collected at the commencement, as in the previous in¬ 
stance : the gas, however, soon contains nitrogen, which 
latter decreases gradually, till, having attained a maxi¬ 
mum, it finally disappears. This reaction is explained 
by the fact that, during the experiment, the acid, be¬ 
coming gradually -weaker, is at length no longer able to 
evolve nitrogen. The liquid was carefully examined for 
nitrous oxide, which, owing to its ready solubility, would 
have remained in solution, but the results in this par¬ 
ticular case were always negative. 
IY. When the solution is much more concentrated, 
containing only 15 eq. of water, no hydrogen is evolved 
from the negative pole, although oxygen is freely libe¬ 
rated from the positive pole ; the whole of the hydrogen 
set at liberty reacts upon the acid, and the products of 
* Journ. Pharm. [_4J, xiii. 266-270, from the Journ. of 
the Chemical Society, 
this reaction remain at first dissolved. The solution 
surrounding the negative pole soon acquires a blue 
coloration, and then hydrogen, mixed with a small quan¬ 
tity of nitrogen, is slowly liberated. After some hours a 
new gas appeared, which gradually but completely re¬ 
placed the hydrogen, and finished by disappearing in its 
turn, as shown in the accompanying table. The gas 
proved to be nitric oxide :— 
Gas collected. 
1 
hour. 
12 
hours. 
15 | 20 
hours, hours. 
1 
30 
hours. 
48 
hours. 
50 
hours. 
Hydrogen . . 
98-96 
92-5 
— 1 69-1 
83-1 
98-6 
100 - 
Nitrogen . . . 
1-04 
3-5 
1-4 3-4 
10-1 
1-4 
— 
Nitric oxide. 
4-0 
98 - 6 J 27*5 
6-8 
1 1 
Towards the termination of the experiment, the nega¬ 
tive liquid contained a considerable quantity of ammonia, 
and possessed, moreover, the characteristics of an aque¬ 
ous solution of nitrous acid : it reduced permanganate 
of potassium and chloride of gold, and when neutralized 
with an alkali, not only blackened a solution of ferrous 
sulphate, but disengaged ruddy vapours upon the addi¬ 
tion of dilute sulphuric acid. 
Y. When the pure acid, N 2 0 5 4H 2 0is electrolysed, 
the evolution of gas, at first nil, soon becomes extremely 
rapid, and the gas which is collected is entirely absorb¬ 
able by a solution of ferrous sulphate: it is pure nitric 
oxide. After a while hydrogen makes its appearance, 
when the liberation of nitric oxide slowly ceases. 
The foregoing gaseous mixtures were analysed by 
mixing them with oxygen, and then adding a solution of 
caustic potash; the excess of oxygen having been re¬ 
moved by pyrogallic acid, the hydrogen was determined 
by explosion in the usual way. In conclusion, the 
author states that these experiments show that nitrous 
acid, nitric oxide, nitrogen, and ammonia result from 
the reducing action of hydrogen upon nitric acid, and 
that they furnish additional evidence of the energetic 
action of hydrogen gas, when the latter is capable of 
exerting its power in the nascent state. 
CINCHONA CULTURE IN THE EAST. 
According to the last published official report recently 
received on the cinchona culture in Java for the second 
quarter of the present year, the number of cinchona plants 
of all ages, sorts and sizes, have increased during that 
period from 1,730,705 to 1,741,525. In April and May all 
the developed cinchona plants of the valuable sorts planted 
out in open ground were pruned, to the manifest advan¬ 
tage of the trees. This pruning yielded 2485 kilogrammes 
of bark, which was forwarded to Batavia in thirty boxes. 
The valuable kinds of cinchona-trees have not yet been 
regularly turned to account; hence it is no wonder that 
the Java barks exported so far have stood no comparison 
with the South American barks of commerce. A dis¬ 
ease has for some time been affecting some of the trees; 
but it has been greatly on the wane during the quarter, 
owing to the favourable weather, and the repeated 
sprinkling of the diseased plants with a decoction of 
tobacco and a solution of the polysulphuret of calcium. 
In May and June an official commission visited the eight 
cinchona plantations, with the object chiefly of endeavour¬ 
ing to trace out the nature of the disease. A long and 
close investigation convinced them that it must be looked 
upon as arising from parasitic vegetation, whose oi'igin 
cannot be pointed out with certainty, because it shows 
itself very irregularly under varying circumstances. 
However much this disease may hinder the undisturbed 
qnd natural growth of the plants, it does not, as a rule, 
kill the latter ; many of them, though severely attacked, 
have been able to recover vigorously. It has also been 
ascertained that this disease is not peculiar or confined 
ito the cinchona plants, for it has been observed elsewhere 
