RESEARCH FOR ARSENIC AND ANTIMONY. 
229 
a larger proportion of arsenic than that which existed in the 
copper-gauze used by Dr. Odling and myself in the Smeth- 
urst case.* 
* This case drew from Mr. Herapath, in the capacity of “ amicus justitise,” 
a letter, which was published in the ‘Lancet’ of September 3d, 1859, and in 
most of the medical and daily journals. It condemned in strong language 
the use of copper containing arsenic, and suggested that all convictions 
which had for twenty years taken place upon the use of Reinsch’s process 
could be only regarded as judicial murders. Let the reader consider the 
value of such a condemnation coming from a man who, unfortunately for 
his appeal to justice, had himself during sixteen years employed and recom¬ 
mended for Reinsch’s process a strongly arsenicated copper wire ! It will 
be perceived, by his mode of operating, too, that not satisfied with deposit¬ 
ing arsenic on the impure copper, he directs that the deposit, should be 
continually scraped off as it is formed, thus mixing the impure copper with 
the supposed arsenical deposit. In this letter, Mr. Herapath states that 
the one thousandth part of a grain of arsenic is quite sufficient, by Reinsch’s 
process, to furnish the five proofs which he requires for scientific evidence 
on a charge of murder. A few grains of his No. 13 wire will, under certain 
conditions, yield this quantity of arsenic, which, in ignorance of its presence 
as impurity, an analyst might easily assign to the liquid or solid examined. 
Measured by his own standard, and quoting his own words, “ what, shall be 
said of the convictions and executions which have taken place during six¬ 
teen years upon Mr. Herapath’s evidence, if the same impure copper has 
been used by him in the process of Reinsch ?” 
Either Mr. Herapath knew that the No. 13 wire, which lie employed and 
recommended, contained arsenic, or he did not. If he did know it, then 
he deceived the public and profession by the publication of his letter; if he 
did know it, then, instead of acting as censor of others, he should have 
acknowledged with penitence his own chemical transgressions for the long 
period of sixteen years, and have thanked those who, for the first time, in 
1859, pointed out to him the danger of the course which he was pursuing. 
If danger ever arises from the presence of impurities in chcmieais, that 
danger is undoubtedly incurrred in the highest degree when a man is rashly- 
prepared to swear to the presence of poison from the discovery of the 
thousandth part of a grain ! Of Mr. Herapath’s conduct and motives in this 
transaction, I shall only say “Quern deus vultperdere prius dementat.” 
I cannot close this note without, for the sake of contrast, not icing the 
candid and honorable conduct of an excellent chemist ami eminent prac¬ 
titioner, Dr. DouglasMaelagan, of Edinburgh, in reference to the discovery 
of this impurity in copper. Before the fact of the general presence of 
arsenic in copper had been made publicly known by the evidence given by 
Dr. Odling and myself at the trial of Smethurst in August, 1S59, Dr. 
Maelagan had conduct ed a scries of analyses for arsenic by Reinsch’s process 
in a criminal case in Scotland, and had arrived at the conclusion that arsenic 
was present in the fluids and solids of the body. This case came to trial at 
Inverness, some months subsequently to the trial of Smethurst. After 
giving his evidence, and confirming his previous report, Dr. Maelagan 
requested the permission of the Court to correct it, by stating that bv 
reason of certain matters which had become public since Ids first analysis, 
lie had been induced to examine the copper which he had employed in his 
experiments, and he found it to contain arsenic. The proportion, however, 
was much smaller than that, which he had extracted from the liver and 
other organs of the deceased. He had previously tested it in the manner in 
