523 
THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. [December 30, 187L 
and pounding a root called “ kon-niaku-no-dama.” From 
this cloth may bo made boxes, trays, saucepans which 
sustain no injury over a charcoal heat, hags in which 
wine may he put and heated by insertion in boiling 
water, and windows that will withstand the wind and 
rain. Imitation leather and waterproof papers are made 
by mixing oil with the pulp. The juice of parsimmon 
is also sometimes used in making paper intended to resist 
damp. 
It is said th«t the Japanese are acquainted with the 
method of manufacturing paper from rags, but never 
adopt it, preferring to make it from the bark of trees. 
DOUBLE IODIDE OF MERCURY AND COPPER. 
BY MM. WILLM AND CAVENTOU. 
"When sulphate of copper is added to a boiling solution 
of iodomercurate of potassium (Hg-K 2 I 4 ) free iodine is 
disengaged abundantly, and a dark brown powder is 
immediately deposited, which assumes a fine red colour 
in cooling, and contains mercuric iodide and cuprous 
iodide. The salient character of this compound is that, 
whether suspended in water or dried, it becomes darker in 
colour when heated and reassumes its red colour upon 
cooling, without undergoing any alteration from the 
successive changes of temperature. 
M. Mcnsel considers this substance to be a mixture of 
two iodides. The authors, on the contrary, consider 
that it constitutes a well-defined compound. Its coiour 
when cold is darker than that of the mercuric iodide; 
and it is difficult to conceive that a mixture of red iodide 
of mercury and the little-coloured cuprous iodide could 
be darker than the mercuric iodide. Moreover, the mer- 
curio-cuprous iodide, treated cold with iodide of potas¬ 
sium, is decomposed very slowly, although iodide of 
potassium dissolves mercuric iodide with facility. But 
if it be heated, the mercuric iodide dissolves and the 
cuprous iodide remains. 
Upon submitting the cuprous iodomercurate to ana¬ 
lysis, the authors obtained results according nearly with 
the formula Hg (Cu 2 ) I 4 . The analysis was made by 
decomposing the iodide by a plate of zinc, precipitating 
the filtered liquor by nitrate of silver and redissolving 
the metals in nitric acid. The mercury was separated 
from the copper either by precipitating it in the state of 
calomel, or by treating the sulphides with nitric acid, 
which only dissolves the sulphide of copper. The quan¬ 
tity of cuprous iodide remaining after the action of 
boiling iodide of potassium was also determined. The 
formula IIgCu 2 l 4 requires 45-56 per cent, of cuprous 
iodide, and 46 - 4 per cent, was obtained. 
Further evidence that there is a real combination is 
found in the fact, that when treated with ammonia this 
iodide yields two kinds of crystals, both containing mer¬ 
cury and copper. "When the cuprous iodomercurate is 
boiled with ammonia a blue solution is obtained, and a 
very dense liquid that congeals upon a slight lowering 
of the temperature. The blue liquid, filtered, deposits 
upon cooling long blue needles, which are an ammo- 
niacal compound of mercuiio-cupric iodide. The forma¬ 
tion of a cupric compound is easily explained by the 
liberation of the metallic mercury which remains in the 
congealed mass. The authors have not yet completed 
their investigation of this ammoniacal compound, it 
being rendered difficult by the nearly constant presence 
of other crystals. 
The mass, dissolved by boiling water, slightly ammo¬ 
niacal, yields green crystals containing both mercury 
and copper, the latter being in the state of copperas. 
These green crystals appear to be simply a product of 
the addition of ammonia to the mercurio-cuprous iodide. 
In fact, when exposed to the air or treated by an acid 
they reproduce the double iodide, red when cold and 
black-brown when heated, without loss of iodine. The 
blue crystals on the contrary, which are also transformed 
into double iodide upon desiccation, lose their iodine be¬ 
fore losing the whole of their ammonia. 
The authors consider that this preparation might be 
utilized in medicine. 
THE SIMULTANEOUS DISTILLATION OF WATER 
AND CERTAIN ALCOHOLS INSOLUBLE IN 
WATER. * 
BY MM. I. PIERRE AND E. PUCHOT. 
The authors in the course of their investigation of the* 
products of alcoholic fermentation have noticed that when 
a mixture of pure amylic alcohol and water is submitted 
to distillation, the temperature of the liquid rises rapidly 
to 96° C. ; the liquid, at that point, enters into full ebul¬ 
lition, and the temperature becomes remarkably constant.- 
The result of the distillation is a turbid mixture of water 
and amylic alcohol, which separates quickly into two- 
layers ; the upper consisting of amylic alcohol, the lower 
of water only. When the two layers of condensed liquid 
were examined at various times during the distillation, it 
was found that during the whole of the operation, as long 
as the temperature was maintained at 96° C., the volumes 
of water and amylic alcohol condensed were in the con¬ 
stant proportion of two to three respectively. This con¬ 
tinued until the supply of one or other of the sub¬ 
stances was exhausted ; if the original mixture had con¬ 
sisted of less than two volumes of water to three of amylic 
alcohol, the residue was found to be amylic alcohol, 
but, if of more, the residue was found to be water. In 
the latter case the temperature rose rapidly to 100° C., in 
the former to 130° C. 
This triple result—the uniformity of the boiling- 
point ; a boiling-point lower than that of the most vola¬ 
tile of the two liquids ; and the constancy of the propor¬ 
tions in which the two liquids distil simultaneously— 
appeared to the authors to point to a general law, of 
which it would be advantageous to find the expression, 
rather than to an isolated fact; they, therefore, submitted 
to the same process a mixture of water and butylic alcohol, 
which in its slight solubility resembles amylic alcohol. 
The ebullition was at first a little irregular and some¬ 
times tumultuous, but was easily controlled by the ad¬ 
dition of some pieces of platinum wire and one or two 
pieces of pumice-stone. In the presence of an excess of 
water the temperature rose to 90°-5 C., and then remained 
remarkably stationary until the entire disappearance of 
the butylic alcohol. On examining the condensed pro¬ 
ducts during the distillation, it was constantly found that 
they were in the proportion of five parts of butylic alcohol 
to one part of water. If the distillation was continued 
after the exhaustion of one or other of the constituents 
of this mixture, the boiling-point rose to 100° C. if the 
water predominated, and to 108° C. if the butylic alcohol 
was in excess. Thus, in this experiment, as in the first, 
it was found that the boiling- point was constantly lower 
than that of the most volatile of the two substances, and 
that the proportions of the two liquids that distilled simul¬ 
taneously were also constant. 
In the case of the mixture of water and amylic alcohol 
the boiling-point was lowered— 
Compared with that of water .... 4® C. 
Compared with that of amylic alcohol . 34° C. 
In the case of the mixture of -water and butylic alcohol., 
the boiling-point was lowered—- 
Compared with that of water . . . 9°-5 C. 
Compared with that of butylic alcohol 17°'5 C. 
* Comptes Rendus, vol. lxxiii. p. 599, and Journal de 
Pharmacie et de Chimie , 4th ser. vol. xiv. p. 244. 
