236 
RESEARCH I-OR ARSENIC AND ANTIMONY. 
inch in thickness. It is flexible, but breaks when suddenly 
bent. 2. A wire containing 2*8 per cent, of arsenic, having 
a diameter of about the l-100th of an inch. It has the usual 
copper-red colour, and can be bent and twisted upon itself 
without breaking. It manifests no more brittleness than 
ordinary copper-wire of the same thickness. Although it 
contains nearly l-33d of its weight of arsenic, no one, judg¬ 
ing by its appearance and physical properties, would enter¬ 
tain a suspicion of the presence of this substance. 3. A 
third wire of Spanish copper, containing 2 per cent, of 
arsenic. It has about the same diameter as No. 2. It is 
perfectly flexible, and manifests no brittleness whatever. 4. 
A sample of fine British copper-wire, as it is commonly sold, 
with traces of arsenic, it is of about the same diameter, 
but is not so elastic as 2 and 3. Let the reader compare 
these facts with the following statements contained in Mr. 
Herapath's letter:*—“ The hundredth part of a grain of 
arsenic in that quantity (ten grains) of copper, would render 
it so brittle that it could not be drawn into wire at all, much 
less into fine wire fit for gauze.” It is obvious that this che¬ 
mist is either entirely unacquainted with the properties of 
copper containing arsenic as an alloy, or that he relies upon 
the general ignorance of the public and profession in refer¬ 
ence to such matters, to publish a statement wholly opposed 
to facts. 
Having recently examined not fewer than forty samples of 
copper, as it is employed by chemists in the form of wire of 
various sizes, of foil of various thicknesses, and of gauze, 
coarse and fine, I have found arsenic in all of them, and in 
some instances in comparatively large proportion. These 
samples were procured from dealers in this metropolis, from 
various parts of England, from Scotland and Ireland. Some 
of them have been forwarded to me by medical practitioners 
who had employed them as pure in medico-legal analyses, while 
some samples of gauze and foil had been sold as pure by dealers. 
In every instance arsenic was found in the copper; and there is 
no other conclusion to be drawn than that all the copper used 
in commerce, the arts, and chemistry, refined or unrefined, 
contains arsenic in such proportion, as when the metal is 
dissolved or destroyed, to render it unfit for Reinsch’s pro- 
cess.f Mr. Brande stated, in his evidence at the trial of 
* ‘Lancet,’ September 3,1859, p. 248. 
j* Since writing the above, I have met with a passage in Will’s ‘ Analyse 
Chimique,’ translated by Risler (1S58), in which, in speaking of the diffusion 
of arsenic, he says, “ On on rencontre des traces presque toujours dans le 
soufre, le ier, le cuivre , l’etain, et l’antimoine.” 
