174 Disinfection by Hot Air. ing disinfected in it without any charge, or in the case of others, at the following nominal charges: Charges for disinfecting articles at the hot-air chamber. Per day of 9 hours, at disinfecting temperature (300°) ... ... (These charges include coals and attendance.) Disinfecting single blankets, each per pair of double s. d. 80 5 0 0 1 ... quilts, each ... 0 14 0 1 Articles belonging to the poor are disinfected gratuitously, if ordered by medical or relieving officer. It is to be regretted that the citizens of Dublin do not more frequently avail themselves of the great advantages which this hot air chamber offers as a means of stamping out scarlatina, whooping cough, and similar diseases. If this chamber were in constant requisition, I can hardly doubt but that the mortality from zymotic diseases in Dublin would soon be sensibly diminished.1 0 1 02 03 02 The engraving shows the construction of the chamber. The walls and ceiling of the compartment in which the clothes are 2 Anyone requiring clothing to be disinfected at the hot air chamber should write a day previously to the articles being sent to the keeper of the chamber, Corporation Depot, Marrowbone-lane. The articles may be enclosed in sacking or matting and sent in a hand or other cart, but not in a cab or similar vehicle. Deodorization of Sewage. 175 heated are built of brick, and its floor is composed of perforated iron plate. The heat is radiated into the compartment from the exterior surface of a coil of iron pipe, 80 feet long, and which acts as part of the furnace flue. The products of the combustion which takes place in the furnace escape into the atmosphere, without viously mixing with the air contained in the close chamber; no emanations from the infected clothes can pass into the atmosphere, and consequently no one need feel alarmed at the close propinquity of the apparatus. pre Sewage Disinfection.-Solution of chloralum, carbolic acid, or of some such metallic salt as copperas, should occasionally be poured into the sinks, and all other places leading to the sewer. The ash-pit or midden is benefited by the occasional sprinkling of a disinfecting liquid. If there be a cistern of water devoted exclusively to the W. C., pour into it daily a wineglassful of carbolic acid solution. One pound of chloralum powder, five pounds of sulphate of iron, or one pint of carbolic acid are sufficient quantities to add to five gallons of water; if the sewers be very offensive, somewhat stronger solutions may be applied; whilst for watering streets the solution may be ten times weaker. On the whole, carbolic acid seems the best application to sewage. For manure heaps and liquid manure, chlorine and chloride of lime are very unsuitable, whilst iron per chloride and chloralum are suitable applications. If the manure be quite fresh, quick-lime is a good preservative, but this substance acts unfavourably on stale manure. One pound of freshly burnt quick-lime is sufficient for 100 gallons of fresh liquid manure, and it will preserve its fertilising qualities for a long time. The following substances include all the really useful disinfec tants and antiseptics: Nitrous Fumes.-On dissolving copper in nitric acid a colourless gas is evolved, which, on coming into contact with the air, absorbs oxygen from the latter, and produces ruddy fumes-a variable mixture of nitrous acid and hyponitric acid. These fumes are, perhaps, the most powerful of the gaseous disinfectants, but they are so dangerous to life that they should only be used under the immediate superintendence of a scientific or medical man. Chlorine. By heating black oxide of manganese with about four times its weight of commercial muriatic acid, a yellowish green gas, termed chlorine, is evolved. It possesses a very powerful odour, and cannot be safely inspired, even when largely diluted with air. The gas can also be obtained by adding 5 parts of alum cake to 4 parts of bleaching powder, or chloride of lime; or, but in an impure, but equally efficacious, state, by the addition of one part of oil of vitriol to three parts of bleaching powder. A few crystals of potassic chlorate (chlorate of potash), placed in a saucerful of muriatic acid, slowly evolve chlorine. It is a colourless gas, and, like chlorine, cannot be breathed without injury to the lungs. Sulphurous Acid is prepared by burning sulphur. Muriatic Acid.-The acid liquid known in commerce by the name of spirits of salts, or muriatic acid, is water containing in solution about one-third of its weight of hydrochloric acid gas. By boiling the commercial article, the gas which it contains is, in great part, expelled, and it acts as a disinfectant of moderate power. The liquid also possesses disinfecting properties. Condy's Liquid is a solution of permanganate of potassium in water. It acts by freely parting with a large proportion of the oxygen which it contains, when it comes in contact with organic matter, especially if the latter be in a decaying state. Although by no means so powerful as some other disinfectants, it possesses the great advantage of being without odour, and it is, therefore, well adapted for use in the sick room. Carbolic Acid.-Pure carbolic acid is a white crystalline solid; but the commercial article is a thin, tar-like liquid, with an odour resembling that of a mixture of tar and creosote. This substance acts by reason of its great antiseptic virtues. When mixed with animal or vegetable substances, it prevents them from fermenting or becoming putrescent; but it allows them to undergo a very slow and harmless kind of decay, or oxidation, during which process no hurtful matters are evolved. It destroys animalcules and minute plants; but in this respect it is excelled by other sanitary agents. There can be no question as to the valuable disinfecting properties of carbolic acid, and it is to be regretted that its odour is objectionable, and that so many accidents have occurred from persons drinking it in mistake for porter and other liquids. Tar, and tar oils, possess, but in a much feebler degree, the disinfecting properties of carbolic acid; whilst picric acid and benzoic acid (a dear substance) are probably more powerful sanitary agents than carbolic acid. Vinegar and ammonia, though used as disinfectants, are of but little value as such. Sulphate of Copper (Bluestone or Blue Vitriol).—According to the recent experiments of Dr. Dougall, bluestone possesses germdestroying and anti-putrefactive properties equal to those of chloride of aluminium: it differs from the latter, however, in being poisonous. Sulphate of copper instantly removes the odour of sulphuretted hydrogen. Nitrate of Lead has been used as a disinfecting agent, but not largely. It rapidly removes the odour of sulphuretted hydrogen, and may be applied to foul sewage. This salt is poisonous. Sulphate, Sulphite, and Chloride of Zinc are, especially the latter two, good disinfectants, particularly for sewage; but they have the disadvantage of being poisonous. "Burnet's Solution" is simply chloride of zinc dissolved in water; it may be easily prepared by dissolving pieces of zinc in muriatic acid. Ferrous Sulphate (Sulphate of Iron, Copperas, or Green Vitriol) is the cheapest of the heavy metallic salts used for disinfecting purposes. It is applied to manure heaps and sewage; but it is not a powerful sanitary agent. Ferric chloride, or perchloride of iron, has been employed rather largely as a sewage deodorant. It is prepared by dissolving rust of iron in muriatic acid. Bichromate of Potassium (bichromate of potash) is extolled as a disinfectant by Dr. Angus Smith-a distinguished sanitarian, and still more recently by Dr. Dougall: the latter says of chromic acid (prepared by adding sulphuric acid to bichromate of potassium) that its antiseptic power is double that of carbolic acid, and that "it must ere long take the foremost place as a sanitary agent." I think, however, that chromic acid is hardly likely to become a cheap disinfectant. Surgeon-Major O. Nial's experiments with potassium chromate gave results similar to those of Dr. Dougall. "Bisulphite of Lime" has been largely used as an antiseptic, but chiefly for the preservation of meat and other kinds of food. It has been highly commended by several chemists. "M'Dougall's Powder" is a compound of calcium sulphite (sulphite of lime) and carbolate of calcium (carbolate of lime). It is extensively used as a deodorant for sewage, stables, &c. Alum, Lime," Superphosphate of Magnesia," and other earthy bodies, are, or have been, employed as disinfectants, chiefly in the case of sewage. Alum and other salts of the earth alumina appear on the whole to yield tolerably satisfactory results as sewage deodorants. Charcoal in lumps has been found useful in absorbing foul gases from the air of dairies, stables, &c. CHAPTER XVII. SPREADING OF DISEASES AND HOW TO PREVENT IT. A person suffering from a contagious disease is, with respect to the rest of the community, very much in the same condition as a lunatic-both are dangerous to health and life. They are, however, usually treated in a very different manner. The lunatic, if he exhibit the slightest tendency to do violence to any one, is, on the production of a medical certificate, summarily deprived of his liberty, and placed under such conditions as may be deemed necessary to prevent him from injuring any one. On the other hand, the small-pox or scarlatina patient is not interfered with. He may, when barely convalescent, mix, without let or hindrance, in crowds, travel in tram-cars, railways, carriages, and cabs, go to places of worship and amusement, and, in a word, scatter the seeds of disease broadcast amongst the population. But it may be said that the law prohibits persons suffering from contagious diseases from exposing themselves in public. The 26th section of the Sanitary Act, 1866, certainly provides a penalty for such an act; but who ever heard of any one being prosecuted for a breach of this law. People are daily prosecuted all over the United Kingdom for allowing the existence of house nuisances, rooms to be overcrowded, tenement houses to be dilapidated; and but rarely, indeed, do we read of the prosecution of persons for spreading con. tagion amongst the people. Perhaps I may take an extreme view of this matter; but I hold that every person suffering from such a disease as small-pox should be deemed to be dangerous to the community, and should be placed under such conditions as would at least diminish the amount of mischief which such persons at present occasion. No doubt, any such interference with a patient would be considered by many a high-handed procedure, and an unwarrantable interference with the liberty of the subject; but there are few laws enacted for the well-being of the community that do not interfere with the so-called liberty of the subject. The liberty claimed for a scarlatina patient or convalescent is the liberty to freely communicate their disease to healthy persons, and that freedom is certainly one which the body politic, for its own sake, is justified in refusing. There are great practical difficulties in the way of compulsorily isolating infected persons and the convalescent from contagious disease; but they are not insuperable. The law relative to exposure of persons affected with contagious disease should be strictly enforced. No person suffering from such maladies should be permitted to remain in any house containing more than one family, or in any dwelling in which there is not ample accommodation. The prompt removal of persons affected with contagious disease to hospital would materially lessen the current stock of contagion. With respect to convalescents, they should be detained until such time as their medical attendants pronounced them free from contagion, or at least not likely to be capable of communicating disease. Of course, convalescent hospitals should be provided in such cases; but the sanitary authorities have power to erect a sufficient number of these useful institutions. The immediate removal of the contagious sick, and their detention until free from contagion, I look upon as indispensable measures for the eradication of zymotic diseases. Clothing and bedding frequently are the media of propagating disease. Those belonging to persons who have died from small-pox, scarlatina, &c., are frequently sold or sent to the pawnbroker, without having previously been disinfected. In this way disease is often spread. Some years ago I discovered that the cast off straw from the patients' beds in a fever hospital was systematically sold, instead of being burned. No doubt, many poor persons who bought this fever-infected straw and lay upon it contracted the disease. |