2594. The poisoning of the aliments must take place through the medium of their blood, or their sap. If poison therefore does not get into the blood, the death does not ensue. The digestive juice is poison only for the blood, but not for the other systems.
2595. Chemical bodies which induce death, act by destruction of the bodies themselves, not merely by their neutralization or excessive polarization. They do not operate very differently from iron when in a state of red heat. Such is the case with sulphuric acid, nitric acid, alkalies and arsenic.
2596. Now, if these bodies be called poisons, there are thus three kinds of poisons, mineral or chemical, vegetable and animal poisons.
2597. The chemical poisons destroy the mass; they convert the Organic into minerals.
2598. Vegetable poisons reduce the animal to the plant; they do not effect the destruction of the mass in a general sense, but only that which is purely animal, or the nervous system—they are nervous poisons.
2599. The animal poisons destroy what is vegetable in the animal, or the galvanic process—are blood-poisons.
2600. The saliva is the digestive poison.
2601. The saliva is not present, in order to macerate, and so prepare the dry aliments for digestion, but to poison them. Everything else is only a subordinate operation. Now, the process of poisoning takes place only in the blood. The saliva does not act without inflicting a wound.
2602. Strictly regarded, all saliva is poison. There are examples of the saliva of birds, and even of men when inflamed with passion, having acted as poison.
2603. All other animal poisons, contagious principles or miasmata, are analogous to the saliva, being partial salivæ, partial poisons. Diseases of the skin produce tegumentary poisons or salivæ; glandular diseases, glandular poisons; nervous diseases, nervous poisons; diseases of the lungs, pulmonary poisons. The saliva is the blood-poison; the hydrocyanic acid, the nervous poison.