stand at once why the leading symptoms of a cold are violent flow from the nose, sneezing, coughing, with the accumulation of phlegm, and painful soreness in the throat. These symptoms "become intelligible at once from the point of view of local poisoning, and we see in all the circumstances of a cold the "protective efforts" which Nature makes to eject the poison—of whatever kind it may be—from the parts which are specially attacked, just as we often see in diarrhœa the effort to get rid of an irritant, or in fever, with its rapid disintegration of tissue, of the poison that has attacked the system. Of course, as in pneumonia, some slight chill often immediately precedes the attack of cold—the chill, by its arrest of skin action, throwing more poison into the blood, which is sufficient to determine the attack in the predisposed part.
We believe, therefore, that few healthy persons would be subject to cold, unless they lived in impure air. With an old person, or a person in lowered health, it is different. A defective machinery for the circulation of the blood or for respiration might readily result in the waste-poisons being imperfectly separated from the blood, and thus such persons would live in the same state of blood-poisoning and preparation for attack as a young and healthy person does who constantly breathes bad air. Where we have cases of liver or kidney attack following upon a severe chill, we may suppose either that the poisons retained (or formed) near the surface of the body pass into the blood, and then act through the nervous centers upon those organs which happen to be specially susceptible; or that the poisons, imperfectly breathed out at the lungs, are carried directly to those organs.
We wish that it were possible to follow the subject further, but we have already overstepped the limits which the kindness of the editor has allowed. We can only say, in conclusion, that we are convinced that very grave issues are dependent upon the question of pure air in our houses. We suspect that not only liability to cold, but to gout, rheumatism, lumbago, neuralgia, some forms of headache, and many forms of nervous irritation are to be conquered by constantly giving lungs and skin a fair chance of getting rid of these poisons; we feel sure that the irritable temper that so often accompanies severe literary work, and at last ends in the "break down," must largely be put to the account of the impure air breathed through long hours; and we suspect
- The fact that the air that we breathe is delayed for some little time in the bronchia passages before reaching the lungs probably increases the local poisoning, and therefore the predisposition for attack by the germ of the parts when we breathe bad air. In this way perhaps the lungs are protected at the expense of the bronchial passages; and a cold is the violent occasional expurgation of those parts which are specially exposed to the poison.