RESEARCH FOR ARSENIC AND ANTIMONY. 
295 
While, however, there is no reason to believe that the use 
of ordinary copper is attended with any risk in the employ¬ 
ment of Reinsch’s process, merely because it contains traces 
of arsenic in intimate chemical union, it may be a question 
whether, out of deference to public opinion, a substance con¬ 
taining arsenic in any form, or in any proportion, should be 
used for the detection and separation of this poison. In 
gauze, from one out of three evacuations passed by the deceased a few days 
before her death. The gauze employed was undissolved after boiling; and 
unchanged in form and substance. There was no indication that any portion 
of it had been dissolved; and assuming that it could coat itself with arseuic 
in the acid liquid, without undergoing solution (an impossibility if free 
arsenic was not present), it is quite certain, from its small size, that it would 
not contaiu enough arsenic to give such a deposit as was ultimately procured 
upon it. A portion of this deposit yielded a well-marked sublimate of 
octahedral crystals. Some ingenious chemists suggested that a phosphate, 
nitrate, or chlorate might have been present on this evacuation, have dis¬ 
solved the arsenic out of the copper (without dissolving or destroying the 
copper itself), and thus have given rise to a fallacy. The fallacy was in 
their own imaginations, and based on a preconceived desire to account for a 
result by any theory, excepting the true one; namely, that arsenic in small 
quantity was present in the liquid. Two other evacuations examined by the 
same materials yielded no arsenic (they had been passed before the symptoms 
resembling arsenical poisoning had supervened), yet there was no reason to 
suppose that these should have been deficient in the salts assumed to be 
present in the one in which arsenic was detected. The latter evacuation 
contained blood and mucus, such as usually accompany arsenical poisoning. 
There was no blood and but little mucus in the two evacuations from which 
the copper-gauze came out without any arsenical deposit upon it. 
I must here notice another theoretical objection to the use of Reinsch’s 
process when a chlorate is present, namely, that arsenic may be lost by its 
volatilization as chloride. This preseuts no difficulty: the operator, if he 
believes in the reality of the objection, has only to carry on the boiling in a 
retort, and to collect the distilled product in a receiver. The chloride of 
arsenic, however, is not likely to be carried over. But is this a fact, or is it 
a speculation? In the correspondence published in the medical journals, it 
was set down as a fact. On distilliug a mixture consisting of seven grains 
of chlorate of potash, with one drachm of pure hydrochloric acid and eight 
drachms of water (the usual proportions for separating arsenic), and adding 
to this twenty-five grains of arsenicated copper-gauze cut into fine pieces, 
the acid liquid collected in the receiver after the operation had continued for 
more than an hour contained not a trace of arsenic. Pure zinc was placed 
in it, and the gas produced was passed into a solution of nitrate of silver. 
There was no change, even after the zinc had been exhausted. The arsenic 
is, in fact, converted to arsenic acid and retained in the retort as arseniat.e of 
potash, in the midst of the diluted acid and of the chloride of copper formed 
at the expense of the gauze. Even if chloride of arsenic were produced, it 
would be deposited on the undissolved copper. 
If, therefore, Reinsch’s process has hitherto been avoided under these 
circumstances, because it might lead to the loss of arsenic, this is an error; 
if because it might introduce arsenic into the liquid under examination, 
then this implies that the operator must have been in the habit of knowingly 
using an arsenicated compound of copper for the separation of arsenic. 
