“It occurred to me that as Messrs. Norblad, Champneys, and myself had distinctly seen among the contents of the stomach some undigested apples, that the seeds or pips of the apple might give rise to the formation of prussic acid by distillation. I therefore determined on making an experiment to see if any and what quantity of prussic acid they were capable of producing. Accordingly the seeds from fifteen apples were bruised and put into a retort with some distilled water, and about an ounce of liquor was distilled off. On the application of the tests before spoken of, Prussian blue, in exceeding small quantity, was produced. On testing the last product of distillation, no Prussian blue was found. I have the whole of the Prussian blue thus produced.
“About ten days ago I was applied to and requested to make more experiments for the purpose (if possible) of discovering the whole amount of prussic acid originally contained in the contents of the stomach, or at least of that portion brought to me. I stated that I had not the means in my possession of doing so, and that Mr. Norblad or Mr. Champneys possessed almost everything relating to the matter; but I thought it possible, if I had the remainder of the contents of the stomach, and that if it were contained in the same bottle in which it was originally brought, I might be able to do so—having a distinct recollection of about the height at which the matter stood in the neck of the bottle. Mr. Champneys, on Saturday, the 8th of February, delivered, with other matters, into my charge, the remainder of the contents of the stomach which had not before been subjected to any operation or experiment, and which, when I gave it him back, after my former experiments, I requested him to keep in a cool dark place for further investigation, should it be deemed requisite. The bottle was tightly corked and securely tied over with a piece of bladder. Before uncorking it, I made a mark with a file outside the bottle coincident with the surface of the contents in the interior. I then emptied the contents into a glass alembic, washed the bottle out with a little distilled water, and added this to the matter in the alembic. The head of the alembic was then put on, a condensing apparatus attached, the alembic placed as before on a salt-water bath, the bath brought to the boiling point, and distillation conducted until the whole of the prussic acid was expelled. A solution of nitrate of silver was put into the recipient for the purpose of seizing hold of the hydrocyanic acid the moment it reached that vessel. By this process I succeeded in obtaining 1·455 grains of dry cyanide of silver, very slightly contaminated with chloride of silver. The latter did not amount to a quantity which could be collected and weighed. But if I allow 0·025 grains, and call the quantity of cyanide of silver produced in reality 1·43 on the quantity operated on in this instance, it must be very near the truth. But as the quantity operated on in this instance formed only 51 parts out of the 180 of the whole volume of the contents of the bottle as it was first brought to me, the following proportion will show how much was contained in the whole. For if 51 parts give 1·43 grains of cyanide of silver, 180 parts will give 5·047 grains of cyanide of silver. This quantity of cyanide of silver is equivalent to 1·002 grains of real hydrocyanic or prussic acid, which is equal to 50 grains of the prussic acid of the strength of the London Pharmacopeia. The determination of the relative quantity operated on, and the original volume of the contents of the stomach, was ascertained by measuring, with water, the bottle filled, as near as possible to remember, to that part in the neck where the contents originally stood, which was 180½ drachms, and to the mark made by the file 51½ drachms.
“I may also remark that the contents of the stomach, after distillation, was still strongly acid, occasioned most probably by the acid in the beer, and also by the acid which is invariably produced during the process of digestion.”[13]
During his examination, Mr. Cooper produced the bottles containing the Prussian blue produced from the stomach and from the apple-pips—the former dark blue in colour, the latter hardly more than tinged with it. When placed side by side on the front of the witness-box the marked contrast caused much excitement in Court.
The cross-examination of this witness by Mr. Kelly was so important, that though very lengthy it is necessary to give it in considerable detail.
“Until this case,” said the witness, “I had never examined the contents of a human stomach where a person had been killed by prussic acid, or a human stomach containing prussic acid. Respecting the effect of prussic acid on the stomach and tissues of the body, my knowledge is only theoretical. Prussic acid, which I have smelt from its most concentrated to its weakest state, has a peculiar smell; it affects different persons differently. When I smell it, it affects spasmodically the back of the throat. But it loses its smell in combinations. I am not aware what quantity of prussic acid destroys life. I have no practical knowledge on the subject. The case I am most familiar with is that of the seven epileptics.
“I began my investigation with the view of seeing if oxalic acid was present. I recognised the odour of beer more strongly in the contents of the stomach than anything else. I did not trace the smell of prussic acid in them, nor feel any spasmodic affection in the throat in smelling them. I did not come to the conclusion, after trying for those acids and mercurial poisons, which I did not discover, that there was prussic acid in the stomach, but I remarked to those present at that time, ‘Well, if this person has taken poison, it must be prussic acid.’
“I have no idea how much Prussian blue I obtained from the first experiment, as it was made in a hurry. (The bottle of dark blue liquid was here shown again.) I thought the obtaining evidence of its presence sufficient. I got more Prussian blue in the second experiment than in the first, and more in the third experiment than the second. I have not calculated the total amount of Prussian blue in the bottle.”