- fallible one or not, as to shewing the presence of arsenic in
solution?—I conceive it not to be so.
Do you recollect who it was that first proved this test?—I don't know who it was that proved it first; but the first time I ever saw it described was in a medical publication by Dr. Marcet, lecturer in Guy's Hospital.
Do you happen to know whether there be any thing else, besides arsenic, which, if submitted to the lunar caustic, would produce the same result as it would with arsenic?—I do.
What else?—If there be any alkaline phosphate, it would put on the same appearance, and throw down the same yellow precipitate.
Do you know whether phosphoric acid and salts be contained, or abound in the human frame?—I have been led to believe so.
Did you hear Dr. Edwards give his evidence as to the test also of the sulphate of copper?—I did.
Have you made any experiments as to the sulphate of copper?—I have.
We have been told that the sulphate of copper, when added to any liquid or fluid containing arsenic, will throw down a green precipitate?—Yes, it will have that effect; and I have made that experiment.
Have you made any experiment in order to ascertain whether any green precipitate would be thrown down by sulphate of copper, when applied to any other solution than that of arsenic?—I have tried it with an infusion of onions and animal matter.
(By Mr. Justice Abbott.) What was the result?—A green precipitate resembling that which would have been thrown down, if arsenic had been present.
(Cross-examined by Mr. Sergt. Lens.)
Did you happen to attend when Dr. Edwards was the chemical lecturer at St. Bartholomew's Hospital, in London?*
