The disease derives its name, as everyone knows, from the peculiar sound which attends the cough, and which is due, as is the sound of croup, to spasm of the upper part of the windpipe. It is equally characterised by the cough returning in fits or paroxysms, which end in a long-drawn breath, attended by the hoop. An occasional sound like a hoop, in a young child who has a cold, is not so conclusive of a case being one of hooping-cough as is the recurrence of the cough in fits; for until teething is completed, slight and temporary irritation will suffice to produce a passing spasm of the upper part of the windpipe. An ordinary attack of hooping-cough begins like a common cold, but as the little ailment passes off, the cough still continues, the fits of coughing become more frequent, last longer, grow severer and more suffocative, and end with the loud long breath, the hoop; while sometimes no sooner is one fit over than another follows it almost immediately, and quiet breathing does not return until the child is tired out by its efforts. Nevertheless, the child's health continues fairly good, and little or nothing ails it during the intervals of the cough. For about a fortnight the cough usually goes on to increase; and during this time the night attacks especially become more frequent. It then for a week or ten days continues stationary, and then declines, a diminution in the frequency and severity of the night attacks being in general the first sign of amendment, and at the end of six weeks from the beginning of the attack the child is in general quite convalescent. Even then, however, a trifling cause will reproduce the characteristic cough for a few days, and not seldom for many months afterwards any cold which the child may catch will be attended by a paroxysmal cough undistinguishable save by its milder character and shorter duration from the previous hooping-cough, though I believe incapable of communicating that disease. In mild hooping-cough there is little or nothing to be done, save to follow the dictates of common sense, and not to neglect them in quest of some imaginary specific--some vaunted medicine which is said to be a certain cure; or such as shutting up the child in a room the atmosphere of which is charged with the vapour of tar, or of carbolic acid, or of sulphur.