“I found no arsenic or antimony in any of the bottles delivered to me by Inspector McIntyre on the 5th and 7th of May, except one, and the homœopathic medicine: that one was bottle 21.[192] When I received this bottle it was about half full of thin, watery-looking mixture, and I tested it. It had a cooling, pleasant saline taste, not repugnant, no smell. I detected nothing wrong with the taste. I evaporated some in a glass, and examined it by the microscope, and then found it was not tartar emetic, as I thought. I then applied the tests for arsenic, and every test I tried was destroyed, and failed to show the existence of arsenic, owing, as I supposed, to there being in it, and my tests convinced me that there was, something very peculiar about it that I had not met before. I tried Reinsch’s process, but I found that it dissolved the copper-gauze as soon as I put it into the liquid. I then determined to extract this noxious agent, and continued to put in copper-gauze until it no longer possessed the power to dissolve it. I then put in a piece of copper, which at once received the arsenic. I was able to decide by these tests that the mixture was chlorate of potash. I found there was of chlorate of potash 7 grains to the ounce, or 1 and 6/10ths per cent., and there was a grain of arsenic to every ounce. I found that the taste of the liquid in this bottle was such that no one would be likely to suspect that it contained arsenic, more particularly as the quantity of arsenic was so small that the liquid could be mixed with any kind of food and swallowed without the person being aware of it.[193] In the bottles brought to me by Dr. Berry[194] I found arsenic—that was white arsenic. I could not give an opinion on that in the evacuation (No. 2), as that was mixed with blood and mucus. In No. 1 there was biliary matter without any metallic substance.”
Subsequently to the conviction of Smethurst, Mr. Herapath wrote the letter to the Times, on the 27th of August, before referred to in the Lord Chief Baron’s communication to the Home Secretary, in which, after a wordy and personal attack on Dr. Taylor, with special reference to his having used for twenty years untested copper, he said:—
“But was the arsenic said to have been found in bottle 21 really in the copper used to prove its presence? Could the copper wire-gauze dissolved by 7 grains of chlorate of potash and its associated hydrochloric acid deposit one grain of arsenic? In the face of all England, I say it could not. The 100th part of a grain of arsenic in that quantity 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. The fact is the whole set of operations were a bungle. Reinsch’s process is inapplicable where nitrates or chlorates are present. Taylor must have known this: it was well known then that chlorates, nitrates, arsenates, and other oxidizing agents, interfered with Reinsch’s process. When Taylor found the copper dissolved—he knew that one of these oxidizing agents was present—he ought then to have either used Marsh’s test instead of Reinsch’s, or should have prepared the solution by sulphurous acid first. The method he did use was as dangerous as could be.”
Whether Mr. Herapath communicated this opinion to the friends of Smethurst before the trial, as he ought to have done, does not appear. At any rate he was not called for the defence, and his opinion was apparently only made public after the conviction. It stands, therefore, like all the other communications laid before the Home Secretary, untested by cross-examination. How far was he correct?
Taylor does not state how much of the liquid in bottle 21 he took for analysis. Assuming that he took 1 ounce, 7 grains of chlorate would dissolve, at the most, 22 grains of copper. If this yielded 1 grain of arsenic, the copper must have contained 4½ per cent. of that poison—an impossible quantity. Less than ½ per cent. of arsenic renders copper brittle. So far Herapath was right.[195]
(2.) If Taylor was right that what he got was white arsenic, that could not have come from the copper, which can only contain arsenicum—metallic arsenic. Therefore if Taylor’s analysis was not altogether wrong, in bottle 21 there really was arsenic, and the prisoner was proved to have had the materials for poisoning in his possession.
Taylor’s procedure in dissolving up piece after piece of copper, which had not been previously proved, by the same process, not to contain arsenic, was highly blameable, and his assertion that he had previously tried his tests and found them pure, was not strictly true. Altogether, his tests both for arsenic and antimony were not reliable.
ADDENDA.