Some poisons, especially those which are sparingly soluble, are with difficulty removed from the stomach, even by the most incessant and violent vomiting. This is notably the case with arsenic, which adheres to the mucous coat of the stomach with considerable tenacity. But even after all traces of the poison have left the stomach, it may be detected in the solid viscera.
Temporary deposit of poison in the organs or tissues (Taylor): (1) The Liver. (2) The Kidneys. (3) The Spleen. (4) The Heart. (5) The Lungs. (6) The Muscles. (7) The Brain. (8) The Fat. (9) The Bones.
With regard to arsenic, the following table, taken from Taylor, is of importance, as showing the amount of the poison which may be found in the liver at certain intervals:
| After taking the Poison. | Total Weight of Arsenic. | |
| In | 5½ to 7 hours | 0.8 grains. |
| 8¾ hours | 1.2 | |
| 15 hours | 2.0 | |
| 17 to 20 hours | 1.3 | |
| 10½ days | 1.5 | |
| 14 days | 0.17 | |
| 17 days | nil | |
Is it necessary that the poison should be found in the body or in the evacuations to lead to a conviction for poisoning? On this point, Christison was of opinion that if the symptoms, post-mortem, appearances, and moral evidence are very strong, it is not necessary that the poison be found in order to establish a charge of poisoning. This opinion was also supported by the late Dr. Geoghehan, Professor of Medical Jurisprudence in the Royal College of Surgeons, Ireland, and was also virtually acted upon in the case of Palmer, where the non-detection of strychnia was strongly dwelt upon by the counsel for the defence, but without success. Many of the vegetable poisons almost defy detection, except by the symptoms, post-mortem appearances, and some experiments on animals of doubtful value. The detection of poison in the food taken, or in the vomited matters, is of great importance; but it is of still greater importance if it can be found in the urine, drawn from the bladder, this being a proof that it has passed through the system. Here again a caution is necessary—for it must be remembered that poisoning may be feigned or imputed—the poison being mixed with the food and evacuations, and an innocent person accused.
The following suggestions should be carefully considered by every analyst when substances are sent to him for examination:
He should carefully note when and from whom the substances were received; in what state they were received—secured, or exposed—the number of articles, and whether properly labelled. He must make the analysis himself, and state where it was made. The character and nature of the substances examined should be noted, and he must be prepared to give an outline of the methods or processes used for their determination. He must also be able to guarantee the purity of his reagents, and be prepared to answer the following questions:
- 1. Is the poison free or combined?
- 2. What is the strength and quantity found?
- 3. Could the poisonous substance exist naturally?
- 4. How much of the poison found is a fatal dose?
- 5. If no poison is found, is there anything noxious
- or injurious to health?
The analyst may have the following submitted to him for examination: (1) Substances found on the accused, or in the room, or on the person of the deceased. (2) Articles of food. (3) Vomited matters, urine, &c. (4) Contents of the stomach. (5) Solid organs of the body.
He may also have his results called in question for the following reasons: (1) Purity of his reagents. (2) Faulty processes. (3) Hasty conclusions. (4) Experiments on animals.