LOBELIA INFLATA (_Indian Tobacco_).—This plant is a native of North America; and its powdered leaves and seeds have been much used as a remedy for asthma. In one instance, in which a quack prescribed a drachm of the leaves, pain, vomiting, unconsciousness, feebleness of pulse, and contraction of the pupils supervened, and death occurred in thirty-six hours. Ignorant imposters, calling themselves “medical botanists” (more appropriately known as “Coffinites”), have poisoned several simple individuals, both in England and America, by physicing them with this mischievous and powerful drug. COLCHICUM (_Colchicum autumnale_, _Meadow Saffron_).—This plant grows in most damp meadows. Its noxious properties are due to the active principle _Colchicia_, which in its effects is allied to that contained in white hellebore, _Veratria_. In two instances less than half a grain of colchicia proved fatal to adults. _White Hellebore_ (_Veratum album_) is a poisonous plant which, when taken internally, has caused violent sickness, purging, dilatation of the pupils, great prostration, and lowering of the heart’s action, cold sweats, convulsions, and death. At the same time it is powerful in relieving pain. Its properties are due to _veratria_, an alkaloid, which may also be prepared from the seeds of the Asagræa officinalis, or Cevadilla seeds, and from Veratrum viride. Gentle emetics, purgatives, and stimulants are the means employed to prevent death in poisoning by any of these vegetable substances. They all produce extreme depression, hence stimulants must be freely used. CHAPTER XXIX. ASPHYXIANTS. NOXIOUS GASES, PRODUCING NEUROTIC SYMPTOMS. The most important of these asphyxiant noxious gases are carbonic oxide, carbonic acid, sulphuretted hydrogen, and carburetted hydrogen. CARBONIC OXIDE is a much more dangerous poison than is carbonic acid, but poisoning with it in a pure state is rare. It constitutes an ingredient in most vapors produced by burning coke or carbon, especially if the combustion is imperfect. It forms with the coloring matter of the blood a remarkably stable compound of a light red color; in point of fact it is the impossibility of exchanging carbonic acid for oxygen in the lungs which causes death. After death the blood is bright red in hue. CARBONIC ACID GAS.—This heavy inodorous gas is the cause of numerous accidents, owing to the variety of sources from which it is produced. It is formed from burning fuel, from the calcination of limestone or chalk, and it is a product of respiration. It is diffused through wells, coal-mines, and caverns. During fermentation it is largely given off, and accumulates in beer vats. The vapor of charcoal partly owes its poisonous properties to carbonic acid gas, as does that arising from lime and brick-kilns. In this country suicides rarely resort to carbonic acid gas to accomplish their ends; in France they very frequently do so.