634 ^^^ POPULAR SCIENCE MONTHLY. 



groans of air-fearing fellow-passengers, and risk cinders and smoke 

 rather than the miasma of the galloping man-pen. 



It would be a mistake to suppose that " colds " can be propagated 

 only by direct transmission or the breathing of recently vitiated air. 

 Catarrh-germs, floating in the atmosphere of an ill- ventilated bedroom, 

 may preserve their vitality for weeks after the house has been aban- 

 doned ; and the next renter of such a place should not move in till 

 wide-open windows and doors and a thorough draught of several days 

 has removed every trace of a " musty " smell. 



If a bronchial catarrh is accompanied by a persistent cough, it in- 

 dicates that the affection is deep-seated, and that it has probably spread 

 to the upper lobes of the lungs. Arm-exercise and a mild, saccharine 

 diet generally suffice to loosen the phlegm and thereby remove the 

 proximate cause of the evil. But, if those remedies fail, there is a 

 presumption that the chronic character of the affection is due to a 

 permanent external cause of irritation, which can be removed only by 

 a change of air. In such cases cough-sirups merely palliate the evil. 

 Medicines, counter-irritants, and fasting are in vain, if the lungs of 

 the patient are constantly impregnated with new morbific genns ; even 

 exercise can do little more than alleviate the distress of the symp- 

 toms ; a radical cure is impossible as long as every night undoes 

 the work of the preceding day. In a home of prejudices the patient 

 should at once change his bedroom and take care to profit by the 

 change. 



A neglected catarrh may result in an attack of pleurisy. Each 

 lung is inclosed in a sack-like serous membrane, which connects with 

 a similar membrane lining the inner surface of the chest. This double 

 integument, known as the pleura, or the visceral and parietal layer of 

 the pleural membrane, communicates both with the lungs and with 

 the upper air-passages, and is more or less affected by every morbid 

 condition of the respiratory organs. Pleurisy, or the congestion of 

 the pleural membrane, is generally an inflammatory complication of a 

 chronic catarrh. The original affection may have apparently subsided. 

 Counter-irritants, alcoholic tonics, etc., have subdued the cough ; with 

 the exceptiori of an occasional uneasiness about the chest, the condi- 

 tion of the patient seems greatly improved ; only an abnormally rapid 

 pulse justifies a suspicion that the smothered fire has not been wholly 

 extinguished. A change of residence or plenty of out-door exercise 

 may perhaps ratify the sham-cure. A normal pulse would give assur- 

 ance that the masked fever has really subsided. But under less favor- 

 able circumstances an oppressive heat and a strange feeling of un- 

 easiness will some day announce the approaching crisis of the latent 

 disorder. Chills follow at shorter and shorter intervals, and at last 

 a pricking pang in the region of the upper ribs reveals the seat of the 

 affection. Breathing soon becomes so painful that the patient finds 

 no rest in a horizontal position, but has to sit up in his bed, and may 



