Dissections show the following appearances in the trachea. 1. A slight degree of inflammation. 2. A thick matter resembling mucus. 3. A membrane similar to that which succeeds inflammation in the pleura and bowels, formed from the coagulating lymph of the blood. 4. In some cases the trachea exhibits no marks of disease of any kind. These cases are generally violent, and terminate suddenly. The morbid excitement here transcends inflammation. Similar instances of the absence of the common signs of disease after death, occur in other parts of the body. Where the cynanche trachealis has appeared in the high grade which has been last mentioned, it has been called spasmodic. Where the serous vessels of the trachea have been tinged with red blood, it has been considered as inflammatory. Where a liquid matter has been found in the trachea, it has been called humoral; and where a membrane has been seen adhering to the trachea, it has received from Dr. Michaelis the name of angina polyposa. But all these different issues of the cynanche trachealis are the effects of a difference only in its force, or in its duration: they all depend upon one remote, and one proximate cause. In the _forming_ state of this disease, which may be easily known by a hoarseness, and a slight degree of stertorous cough, a puke of antimonial wine, tartar emetic, ipecacuanha, or oxymel of squills, is for the most part an immediate cure. To be effectual, it should operate four or five times. Happily children are seldom injured by a little excess in the operation of this class of medicines. I have prevented the formation of this disease many hundred times, and frequently in my own family, by means of this remedy. After the disease is completely formed, and appears with the usual symptoms described by authors, the remedies should be 1. Blood-letting. The late Dr. Bailie of New-York used to bleed until fainting was induced. His practice has been followed by Dr. Dick of Alexandria, and with great success. I have generally preferred small, but frequent, to copious bleedings. I once drew twelve ounces of blood, at four bleedings, in one day, from a son of Mr. John Carrol, then in the fourth year of his age. Dr. Physick bled a child, of but three months old, three times in one day. Life was saved in both these cases. Powerful as the lancet is, in this disease, its violence and danger require that it should be aided by 2. Vomits. These should be given every day, or oftener, during the continuance of the disease. Their good effects are much more obvious and certain in a disease of the trachea, than of the lungs, and hence their greater utility, as I shall say hereafter, in a consumption from a catarrh, than from any other of its causes. 3. Purges. These should consist of calomel and jalap, or rhubarb, and should always follow the use of emetics, if they fail of opening the bowels.