The usual symptoms in man and the higher order of animals are giddiness, headache, obscurity or deprivation of the sight, stupor or perfect insensibility, palsy of the voluntary muscles or convulsions of various kinds, and towards the close complete coma. The symptoms of each poison are pretty uniform, when the dose is the same. But each has its own peculiarities, either in the individual symptoms, or in the mode in which they are combined together.
The morbid appearances they leave in the dead body are commonly insignificant. In the brain, where chiefly the physician is led from the symptoms to expect unnatural appearances, the organs are in general quite healthy. Sometimes, however, the veins are gorged with blood, and the ventricles and membranes contain serosity. The blood appears to be sometimes altered in nature; but the alteration is by no means invariable, and sometimes none is remarked at all. Many of the statements to be found in authors on the morbid appearances caused by narcotics are far from being accurate.
Before proceeding to notice the genera of this class in their order, some remarks must be premised on the principal diseases which resemble them in the symptoms and morbid appearances. Of these the only diseases of much consequence are apoplexy, epilepsy inflammation of the brain, hypertrophy of the brain, inflammation of the spinal cord, and syncopal asphyxia. Of the Distinction between Apoplexy and Narcotic Poisoning.
Of the Symptoms.—The symptoms of apoplexy are almost exactly the same as those of the narcotic poisons, namely, more or less complete abolition of sense and the power of motion, frequently combined with convulsions. This disease commonly arises from congestion or effusion of blood within the skull; but one variety of it, the nervous apoplexy of older authors, or simple apoplexy of the moderns, is believed to be an affection of the brain, unaccompanied by any recognizable derangement of structure.
Apoplexy and narcotic poisoning may be often distinguished by the following criterions:
1. Apoplexy is sometimes preceded at considerable intervals by warning symptoms, such as giddiness, headache, ringing in the ears, depraved vision, or partial palsy. But it is an error to suppose that warning symptoms always occur; nay, if we may trust the experience of M. Rochoux, they are by no means common: of sixty-three cases which came under his notice nine only had distinct precursory symptoms.[1] Poisoning with narcotics of course has not any precursory symptom except by fortuitous combination. And consequently, if warning symptoms have occurred, the presumption is, that the cause of death is a natural one.
2. Apoplexy attacks chiefly the old. It is not, however, confined to the old. On the trial of Captain Donnellan for poisoning Sir T. Boughton, Mr. John Hunter mentioned that he had met with two in-*
- ↑ Recherches sur l'Apoplexie, p. 70.
