are caused by Hydrocyanic acid, a Sedative,--and by Strychnia, a Stimulant; and vomiting is producible by Tartar Emetic, a Sedative,--or by an external irritant of the mucous membrane. It is by the production of nausea that Antimony becomes so valuable an agent in the control of high fevers and acute inflammations. The force of the heart being diminished, the fever is allayed; and the active congestion of the vascular system, whether local or general, which was produced by the inflammation, and maintained by the violent action of the heart, is effectually subdued. At the same time absorption is favoured by the removal of the pressure from the capillary circulation. For its power therefore as a Special Sedative, by which it produces nausea, Antimony is used in sthenic inflammations generally, especially in those that are rapid, and in which we desire a sudden and powerful action. In such cases it is preferable to Mercury,--which is a simple Antiphlogistic, acting in the blood, and having no operation on nerve. It is thus indispensable in Croup. It is very efficacious in sthenic Pneumonia. Laennec speaks highly of its use in acute Bronchitis. In Fevers, Dr. Graves recommends that it should be combined with Opium. In inflammations of the lungs it is particularly applicable, for it exerts a sedative influence over the nerves of those organs. If a small dose be constantly repeated, and gradually increased to a large one, the system will at length be induced to tolerate the medicine, and it will not produce vomiting. Laennec recommended that it should be given in this way in inflammations. He considered the production of vomiting unadvisable; for by that act the system is temporarily excited, and a large quantity of the medicine rejected, which should have been absorbed into the blood to work out its action there. The soundness of his views on this point has been generally admitted by those who have succeeded him. Given simply as an Emetic, this medicine has been used in the early stage of acute local inflammations, as Ophthalmia and Gonorrh[oe]a. It may cut these short at their outset, by hindering the tendency of the local irritation to excite the force of the heart. When we wish simply to evacuate the stomach, as in a case of poisoning, an irritant emetic, as Mustard or Sulphate of Zinc, which acts at once without producing nausea, should be preferred, for three reasons. Its operation is more rapid. The distressing condition of nausea would be an aggravation of the existing mischief. And the production of nausea, by taking off the pressure from the vascular system, favours absorption, which is the very thing that we wish to avoid. The object of an antimonial Emetic is not so much to empty the stomach as to make a powerful impression on the system.