Popular Science Monthly/Volume 1/May 1872/Disinfection and Disinfectants
|DISINFECTION AND DISINFECTANTS.|
By WILLIAM EASSIE, C. E.
THERE are certain rules to be promulgated respecting the protection of human life from contagion, or from the injurious effects of decomposing organic matters, which may be gleaned from the experience of ages, and which as yet have never been laid down with sufficient clearness.
A writer in a medical journal, the other day, pointed out, from the "Odyssey" of Homer, the great solicitude of Ulysses for the purification of his house with sulphur, and the history of purgation could go still farther back, and bring to light many other interesting memorabilia. This, however, hardly comes within the scope of these short papers; neither, as I said before, would any attempt to explain the cause of disease, for it would only be a repetition of wise things said before. Happily, too, the grim dwellers of the threshold are now watched with eye of lynx and nerve of steel, and their newer thrusts at poor mankind met or parried. Names like those of Drs. Parkes and Sanderson, in this respect, are fast becoming household words. For the purposes of this chapter, however, I cannot forbear from condensing the remarks of Dr. Angus Smith, with respect to disease generally. According to this authority, the classes of disease may be caused—firstly, by gases easily diffused in air, such as carbonic acid, nitrogen, marsh gas, and others; secondly, by vapors falling in cold air and taken up in fogs, volatile bodies in fact, that concentrate in cool temperatures, and not to be classed with gases; thirdly, by putrid or decomposing substances, 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 organic matter, and therefore favor a state of atmospheric purity; but carbolic acid is not a deodorizer. It makes, but it does not absorb or destroy, fetid vapors: and it is for this reason that M. Lemaire and others have recommended the use of carbolic acid in conjunction with sulphate of zinc, salts of iron, chloride of lime, and so on.
There is indisputable similarity between the working of putrid germs and of the seeds of the most virulent plagues. Fevers were classed of old as putrid diseases, and any one who has witnessed the prompt decomposition and the foul emanations of fever stricken beings, whether human or brute, can readily understand that it was no very India rubber like stretch of the imagination that led our forefathers to confound contagion with putrescence.
It is, however, necessary to learn that, in practising Disinfection, we have to neutralize the products of, or check the decay of healthy matter separated from living plants or animals, and that we have likewise to destroy specific elements of contagion, elements which differ in the various maladies that are known to be transmissible from the sick to the healthy. In order to illustrate this, let us take the case of sewage. The excreta of healthy human beings decompose, and the sewer gases belong to the class of irrespirable gases which cannot be absorbed into the system without producing serious ill effects, and even symptoms such as characterize a putrid fever—vomiting—faintness followed by prolonged stupor—fetid diarrhœa, and even death. The results are apparently undistinguishable from typhus fever. The line of demarcation, between a malignant fever produced under such circumstances and fevers due to a specific virus, has not yet been satisfactorily established.
The foregoing symptoms result also from decomposing matters passing into the blood otherwise than by the lungs, and whole hecatombs of slain, through the instrumentality of hospital gangrene, pyæmia, puerperal fever, and allied diseases, testify to the great dangers arising from the diffusion of solid or fluid matters in a state of decomposition. In dealing with the excreta of the sick, it is not the volatile elements and simple gases that we have to fear, but the materials that adhere to any thing and every thing on and around the sick, and, if ever we allow them to pass from the sick room, it is quite impossible to control them. If we even let them pass in any quantity from room to room or house to house in atmospheric currents, we cannot trace them until they have victimized fresh subjects susceptible to their pernicious influences.
For our purpose it may be accepted as proved that successful disinfection must aim at preventing decomposition in simple putrescible matters, or must aim at attacking fever germs as soon as discharged by the patient. It is desirable that a disinfectant should be an antiseptic—viz., an agent that arrests chemical change in animal or vegetable matters, and it must be a deodorizer, or capable of fixing the most noxious gases evolved. It has been erroneously believed that sulphuretted hydrogen is the principal deleterious gas which disinfectants have to encounter the worst kind of vermin to ferret out. Prof. Way, however, asserts that the gaseous elements that are usually foul smelling and hurtful are ammoniacal.
The best disinfectant to deal with sulphuretted hydrogen, such as is evolved in the emptying of a foul ash pit, would be salts of iron or chloride of zinc. Salts of iron and copper are antiseptics and very active deodorizers, and would have been used even more extensively than they have been, had they been harmless. But the iron salts stain all they come into contact with, and copper salts are injurious to life. Zinc salts are also inimical in this latter way. A disinfectant, to be available in the homes I am endeavoring to depict, must necessarily be harmless, and until quite recently it was not easy to find such an agent. The alkaline permanganates have been extolled as disinfectants. They are in many instances admirable deodorizers, but the fact that permanganates are sparingly soluble in water renders their employment very difficult, except in dealing with small accumulations of putrid matter. The use is too limited to enable us to rely on them for systematic disinfection.
There is one volatile deodorizer and disinfectant that has been recommended very strongly in some cases by Dr. B. W. Richardson and Mr. Spencer Wells, and that is iodine. In some virulent diseases attended with fetid discharges, a little iodine placed in a box, with a little muslin to confine it, is sufficient to render the room tolerable to the attendants upon the sick. For similar purposes, peat, seaweed, wood, or animal charcoal, have been recommended, owing to the avidity with which they condense the gases of decomposition within their pores. For some years, Prof. Gamgee has used charcoal charged with sulphurous acid as an active antiseptic, and he now suggests the use of charcoal mixed with chloride of aluminium, or, as he popularly calls it, chloralum. The sulphurous acid renders air irrespirable, but chloralum, which is a deliquescent chloride of aluminium, attracts and neutralizes the noxious elements of a poisoned atmosphere.
Having attempted to show that disinfection must be an everyday practice in the household, and that disinfectants must necessarily be harmless antiseptic deodorizers, it is not difficult to establish a code of rules of almost universal application. There is a caution that should be given at all times in a household: Servants cannot be expected to understand the use of disinfectants any more than they can be trusted to carry out a system of ventilation. Disinfection and ventilation, therefore, should, to a large extent, be automatic processes and, happily, such things are to be found.
A fusion of the two processes of disinfection and ventilation has been tried, of late, in the following manner: The space occupied by a top pane of glass is fitted up with a piece of metal which slants from the bottom upward, and the top is rounded in shape and perforated. Inside this wedge shaped ventilator are two shelves, pierced with holes, the top one being made to carry a box of charcoal and the bottom one a piece of sponge. By this double contrivance the inventor and patentee, Dr. Howard, of St. John's, Canada, claims not only to absorb the watery vapor of the incoming air by the sponge, and disinfect any foul air that may seek entrance by means of the charcoal, but also to warm the cold air by the amount of friction it has to undergo in its ingress through the body of a ventilator which is already somewhat heated by the warmth of the room. If the wind blows too strongly upon the outside mouth of the ventilator, Dr. Howard proposes a sliding valve to work up and down inside the pane occupied by the apparatus. I cannot but regard such a contrivance as a clumsy one. It may be said to stand in the same relationship to either per feet ventilation or perfect disinfection that spurious freemasonry does to what is called the pure craft masonry, or certain litharges to good white lead. There is no necessity, either, to filter the air of a room in such a manner.
There can, however, be a strong case made out why the water closet pans of a house should be disinfected, and I am able to point out an apparatus which fulfils every requirement for that purpose. It is exhibited in the diagram, both in section and elevation, and is known as Brown's patent self acting disinfector. The object is to deliver at every upheaval of the handle a certain portion of a fluid disinfectant; formerly it was exclusively Condy's fluid, now it is chloralum. The construction is the essence of simplicity. In a metal, glass, or earthenware vessel, holding a gallon of disinfecting fluid, a metal siphon is fixed, and the bottom is coiled and has a small inlet as shown, by which means the siphon fills itself. When the closet handle is raised, the water rushing down the supply pipe to flush the basin causes a vacuum in the disinfecting siphon, and its contents are blended with the water. By this means a portion of the deodorizing fluid is retained in the trap or basin where it has no sinecure of work to perform. The siphon refills in a few seconds, and, as only a certain quantity is discharged, a pint of disinfecting fluid, costing one shilling, mixed with sufficient water to make up the gallon, will serve about 140 distinct actions of the closet. The cost of the apparatus is about ten shillings, and it can be fixed in an hour to any patterned water closet whatever. The vessel containing the fluid is usually fixed upon a bracket in a corner above the seat. This kind of apparatus can be fixed to a tap in the stable, or anywhere else, and water containing a percentage of the medicated fluid drawn off into buckets, or run off into the pavement drains. They can be obtained at the depot, 58 The Exchange, Southwark.
Such disinfectors are not new, but the above is the simplest. A patent automatic apparatus of a similar kind was introduced some lit tie time ago by Mr. Spencer. It is also worked by the handle of the closet, and fixed on the wall above the seat, but it is too dependent upon a complicated action of wires and cranks its cost is, moreover, thirty shillings. Similar contrivances are sold, adaptable for the earth closets now in use. Whether it be true or not that the partisans of the earth closet first drew attention to the disinfection of the excreta, I do not know, but at all events they were not far behind. I have already given an example of these as applied to the earth or ash closet. As a matter of course, they are chiefly powdered disinfectants. Mr. Bannehr, in his improved ash closet, uses a simple carbonaceous powder, chiefly as an absorbing medium.
Nothing could be more wearisome than wading through the history of disinfectants, and yet an occasional smile would be sure to light up the way. Who would propose to burn incense to the God of Stinks at various times throughout the day, in the shape of patent pastils, composed chiefly of charcoal, sulphur, and nitrate of potass? Or who could be brought to look, Hindoo fashion, on his patrimonial open drain or sewer as a river Ganges, and with religious punctuality set adrift upon the water there a sacred vessel which would admit a certain portion of such water, and also containing a phosphuret which would decompose in contact with the water, the gas and flame thus evolved being understood to neutralize the evaporating poison of Siva, the destroyer? And yet men have paid for leave to rivet such absurdities upon us, and the cry is, "Still they come." Since the time of M. Legras, who, in 1849, claimed to discover and patented not less than twelve disinfectants (three liquids and nine powders), what have householders not had to endure?
Apart from the many simpler disinfectants, such as earth, ashes, charcoal, peat, salt, sulphur, gypsum, alum, vinegar, and tar water, etc., suitable for the coarser purposes of a farm, the disinfectants for the house now in commerce may be reckoned on the fingers of one hand. I have already given a general indication of the action of each, and will only add that these useful agents have now been brought to such a state of perfection, that the person who chooses to make up his own mixtures, puts himself in the position of an ague patient, who, ignoring the labors of chemistry, prefers the powdered Peruvian bark to the sulphate of quinine.
The disinfectant used in a household ought certainly to be a nonpoisonous one. Fortunately, or unfortunately, there is not any choice, for the only one of this description is chloralum, now adopted by the Board of Trade. This is the popular name bestowed upon it by its inventor, Prof. Gamgee. It contains 1,500 grains of hydrated chloride of aluminium to the pint, or about 15 grains to the ounce, and is sold in a fluid and solid state. Slightly diluted, the former will disinfect secretions in the utensils of a sick room; and, exposed in a saucer in its concentrated form, I have found it to remove even the smell which is given off by a newly painted room. In its powdered state it may be sprinkled in cellars, larders, dustbins, ash pits, stables, piggeries, poultry houses, and wherever a smell is continually arising. In the deodorization of sewage, while being pumped over the garden, one gallon of the fluid, or three pounds of the powder, will suffice for 150 gallons of sewage.
As regards the disinfection of clothing in the laundry, Mrs. Meredith, the patroness of the Discharged Female Prisoners' Aid Society, lately wrote to the Standard newspaper as under:
At the wash houses referred to by this lady, a great number of women are employed, and nothing but the washing of the sick is carried on.