that include, with the hurtful gases named under the first head, many organic forms which, transferred to a suitable soil, are capable of working havoc with life and health; and, fourthly, by those more organized bodies in various stages and ferments that have a definite existence, and that multiply the diseases to which they are most allied, whenever they meet with suitable fields for propagation.
Disinfection is practised by fits and starts. With us it has been mainly a summer practice, when our nostrils encounter the smell off offensive matters. Contagion seizes a house, or a town, and for a time the sanitary inspectors, and the awakened people themselves, distribute even the most noxious disinfectants without system, and with the inevitable result of expending the most money with the least possible good result. The destruction of valuable property, a senseless panic, and a relapse into the indulgence of time honored abuses, are the common results of outbreaks of typhus or typhoid fevers, of smallpox, cholera, or any other of the many diseases by which we are punished for grave derelictions of duty. We cannot neglect with impunity the maintenance of personal and household cleanliness ventilation, and an abundant supply of pure water. Soap and soda are the simplest expedients at our disposal for cleansing purposes. Experience teaches us that ancient cities, and even modern human dwellings, are admirably suited to act as reservoirs of contagion, and are constantly polluted by the excreta of the healthy as well as of the sick. We have, therefore, been compelled to resort to disinfection. But such has been our short sightedness in the matter, that the employment of any agent to destroy infection is too often evaded, and has usually been rendered most distasteful and even painful. A nauseous coating has been put upon this very simple pill. A poor woman is sent to the oil shop for a little chloride of lime; a foul room is thereby rendered unbearable, the place has to be thrown open, disinfection is not attained, and the maximum of discomfort is attended with a minimum of benefit.
Some medical men are, I fear, blamable for not estimating with greater precision the real benefits derived from the use of volatile disinfectants. They are all irritating and of bad odor, and a popular belief has arisen that, unless they are foul and caustic, they can do no good service. A distinguished chemist, Mr. J. A. Wanklyn, has very recently shown that the constitution of a poisoned atmosphere cannot be modified even in a small dwelling by an expenditure of material that would be certainly beyond the means of a wealthy person. To diminish the evils of a malign atmosphere, he says, "ventilate," and, while admitting the correctness of this, I shall humbly attempt to show that means may be employed for fixing the poisonous particles floating in a fever chamber without rendering the air of that chamber irrespirable, or without killing a patient by draughts of cold air.
Disinfectants are employed as deodorizers and as contagion destroyers. Such agents as carbolic acid prevent the decomposition of
