=Value of Fumigation.= The actual value of fumigation is a debatable point. Under the best conditions, its efficacy is not a hundred per cent.—far from it—while under unfavourable conditions, when poorly done, its efficacy is so low as to be almost nil. The house whose cracks have been improperly stopped, and the old house, with open chimneys, loose windows, and apertures which cannot be closed, are not made safe by this process. Under such conditions, fumigation not only fails to remove the danger, but it produces a false sense of security. Unless properly done, it were better not to do it at all. We should prefer instead to depend upon vigorous house-cleaning, the use of hot water, soap, and the scrubbing brush, and the destruction of all infective material. Moreover, even under the best conditions, formaldehyde has no powers of penetration. Its action is purely superficial, and only useful for plane surfaces, such as walls, ceilings, and so forth. The most dangerous articles, such as clothing, carpets, bedding, and the like, are totally unaffected by it. We ought to stop teaching that fumigation alone will clear up these infected houses and make them safe for future habitation. The public has been misled as to the value of this measure, and allowed to place far more reliance upon it than has been justified by experience. It is high time for enlightenment. The most that can be said for fumigation is that undoubtedly it kills _some_ germs—so many that it is worth while to continue the practice of it, but too few to afford adequate protection. It must be supplemented by other and more radical measures. =Formaldehyde.= Formaldehyde in one of its preparations is the chemical most generally used, and is more valuable than sulphur, which is now discarded. In most cities, the Health Department attends to the fumigation. In small towns or rural districts, where there is no fumigating corps, formaldehyde is usually given upon application to the local or State Board of Health. In some localities, especially in country districts, there may be no appropriation for this disinfectant, which the householder must then buy himself.[4] Footnote 4: There are many formaldehyde preparations on the market, simple and easy to use, but these may be unobtainable. In this case, an effective method is the combination of formaldehyde with potassium permanganate. For a room containing 1000 cubic feet of air space (a room 10 feet long, 10 feet wide, and 10 feet high), the amount needed is: Potassium permanganate, oz. 111.; liquid formaldehyde, pint 1. Place the formaldehyde in a large galvanized iron bucket (holding 8 to 10 quarts), and drop the permanganate into it. The room should be left closed for six hours; a longer time is unnecessary, a shorter time ineffectual. All cracks, of course, should have been previously stopped.