The most frequent complication with hooping-cough is inflammation of the air-tubes of the lungs. This is extremely frequent during spring and winter, especially in the months of February, March, and April, owing to the prevalence of easterly winds at this season. It is not my intention to detail the symptoms of this affection, only to point out those which will enable a parent to recognise its approach. A parent then may take warning, and fear the approach of mischief, when she observes the fits of coughing become more frequent and more distressing to the child, and the breathing hurried in the intervals of the paroxysm; when any exertion or speaking causes increased difficulty of breathing or panting; when the expectoration becomes less abundant, and difficult to get up; when there is no longer, or at all events less frequent, vomiting after the cough, and more or less febrile symptoms present. If the lungs themselves are attacked by inflammation, most of the symptoms already pointed out will occur; the cough will be frequent, in short paroxysms; the vomiting will not take place; the breathing will be very quick and hurried; and as the disease advances the hoop will cease. If hooping-cough attack a child whilst teething, or from six months to two or three years of age, it is very common for the brain to suffer, and convulsions and water on the head to occur, particularly if the latter disease prevails in the family. Whenever the paroxysm of cough is increased in violence, the characteristic hoop disappearing, and the face becomes very livid; the hands clenched, and the thumbs drawn into the palms; the head hot, and marked fits of drowsiness and languor; and the child, during sleep, screaming out, or grinding its teeth,-- something wrong about the head ought to be anticipated. Of the treatment we have here nothing to say, except that the gums must be carefully examined, and scarified if they require it, and the temperature of the head reduced by cold sponging, or the application of a bag of ice when necessary. The chief duty, however, of the parent is to be alive to these symptoms, and early to detect the incipient mischief, that by a prompt application of efficient means the accession of so formidable a malady may be prevented. To specific remedies for this disease it is scarcely necessary to allude, after what has been advanced, except by way of warning. In the simple form of the complaint such medicines are superfluous, or rather some of them, from their violent properties, most dangerous; in the complicated forms of the disease they are inadmissible. The indiscriminate use of purgatives, also, a parent should avoid. Bowel affections are not an infrequent attendant upon hooping-cough, and always aggravate the primary disorder.