Part 38

One other branch of this subject is worthy of attention. The cleanliness and freedom from offence of the water-closet or of a waste-pipe or drain is in proportion to the frequency with which it is used and to the abundance of the discharge of water through it. A dozen closets used by a dozen persons will be quite likely all to be offensive. If the dozen persons all used only one closet--not a pan closet--the frequency with which its trapping water is removed and the frequency with which its walls are washed would secure its tolerable condition, even if not of the best construction. In this case, as in all others, simplicity should be the controlling principle.

(b) Dry conservancy next after water-carriage is the best and safest system for the removal of human excreta. By dry conservancy is meant the admixture of dry earth, ashes, or similar material with the matters to be disinfected and absorbed. Theoretically, the effect of such admixture is entirely satisfactory; under very careful and intelligent regulation it is practically so. It has been proved, however, by much experience that under ordinary circumstances--that is, where no greater care is given than is ordinarily given to a water-closet or to a common privy--the dry conservancy system is open to serious objections, though always an improvement on the cruder privy-vault. The theory of the effect of a sufficient admixture of earth or ashes with urine and fecal matter is, that by the {219} admission of air thus secured to every part of the material there is a complete oxidation of their organic constituents, similar to, though slower in its operation than, actual combustion in an active fire. In isolated houses and in hospitals, factories, and other buildings not provided with sewerage facilities, there is no question that the earth-closet or the ash-closet affords the best available means for disposal, if we except a system, to be described hereafter, for the distribution of water-carried wastes over or under the surface of suitable ground.

Incidentally--and this is of special interest to the physician--the use of dry earth or of dry ashes in the close-stool of the sick chamber effects not only an immediate and complete deodorization, but without doubt a complete disinfection as well. A quart of dry earth at the bottom of the vessel to receive the deposits, and rather more than a quart with which immediately to cover them, constitutes a means of relief always available and always efficient.

Where the house is provided only with an old-fashioned out-of-door privy the greatest relief and the most complete security may be given at little cost by filling the vault, and placing under the seat a movable box to receive the mixture of fecal matter and of the absorbent material, which, if it is desired to avoid the simple patented appliances made for the purpose, may be kept in a box or barrel in the apartment and thrown down after each use of the closet with the hand-scoop. The objections to the common privy are so obvious, so universal, and so well understood that the practical value of such a means of relief should be appreciated without argument.

(c) Privy-vaults are the sole reliance for the disposal of fecal matter, and often of chamber-slops, of probably 95 per cent. of the population of this country, and of Europe as well. It is curious, in examining the recommendations of public health officers and the requirements of local boards of health, to observe the uniformity with which this most important subject is passed over with the prescription that the vault shall be tight, sometimes that it shall be vaulted over, and sometimes that it shall not be within a certain small number of feet of a boundary-line or of a drinking-water well. These prescriptions are most absurd. It is safe to say, that of the millions of privy-vaults in this country not more than hundreds are really tight; that a still smaller number are so vaulted over as to prevent the free exhalation of the gases of decomposition; that those which are so vaulted over are in all respects of worse sanitary effect than those which have freer communication with the air, and that their possibilities of evil reach many times farther than the limits of distance usually required to intervene between them and the well or the neighboring property. In view of the universality of their use and of the completeness with which modern communities are inured to their presence, it seems almost hopeless to attempt to secure a proper realization of their great defects. They are always the seat of the foulest, and even of the most dangerous, decomposition. They taint not only the air and the soil, but the water of the soil which goes so often to feed our sources of drinking-water, and their local stench is of itself sufficient to sicken all who have not by daily and lifelong habit become accustomed to it. Taking the country at large--farm houses and village houses as well as the dwellings of cities--it is not too much to say that the best sanitary service that {220} can be rendered by those interested in the removal of causes of ill-health would be in securing the abolition of these barbarous domestic appliances. In many ways the cesspool is as bad as the vault, but in some respects the vault is facile princeps as a public and private nuisance of the most annoying and dangerous character. Wherever a public or private sewer is available, wherever disposal by irrigation is possible, and wherever even the crudest attention can be secured for an automatic or simpler earth-closet, the strongest effort should be directed to the absolute inhibition of the common privy-vault.

II. THE REMOVAL OF LIQUID HOUSEHOLD WASTES.--As has been stated above, the liquid household wastes are of much more serious consequence from a sanitary point of view, as compared with excrementitious matters, than the public has been wont to suppose. These, owing to the large amount of water which they contain, are beyond the reach of any system of dry conservancy. They consist almost invariably of a flood of water containing but a small percentage of refuse food, urine, soap, filth of the laundry, grease--everything, in fact, except fecal matter and the coarser garbage and ashes--constituting the waste of the household. Where water-closets are used fecal matter is generally added to the flow, but its relative quantity is small, and its presence or absence does not seriously affect the problem of disposal.

In a house provided with abundant, generally superabundant, plumbing appliances, with a large consumption of water, the whole apparatus is constructed on the theory that all manner of filth is to be taken up by running water and carried well without the house. Where this theoretical end is completely attained there exists a condition of drainage rarely met with and little to be criticised. Unfortunately, the theoretical excellence is rarely secured. Running water confined within a narrow channel, and so compelled to move with force sufficient to give an energetic scouring to the walls of its conduit, may be trusted to carry with it or to drive before it pretty nearly all foreign matter that may have been contributed to it, but the moment this vigorous current is checked, that moment the tendency to excessive deposit begins. It is checked in practice in various ways:

First. By too great a diameter of the pipe: a volume of discharge requiring a velocity of 4 feet per second in a pipe 1 inch in diameter would have a velocity of only 1 foot per second in a channel 2 inches in diameter, and of less than 6 inches per second in a channel 3 inches in diameter. Ordinarily, except as the deposits are removed by decomposition (always objectionable), the deposited matters accumulate and reduce the original bore to the diameter which will secure a cleansing flow. It is the part of wisdom to provide only this bore at the outset or not greatly to exceed it, and it is one of the earliest recommendations of an experienced sanitary engineer to reduce the size of too large bores where they exist.

Second. By the use of traps larger than the pipes leading to them and from them, thus increasing the natural tendency of all traps to stagnation and deposit.

Third. By the use of vertical waste-pipes, which are almost universal, and which are very often necessary. The velocity of a current measured along the axis of the pipe is less if the direction is vertical than if it is laid on {221} a steep slope, because of the tendency of liquids flowing through vertical pipes, which they do not fill, to adhere to the walls and to travel with a rotary movement. I have seen vertical soil-pipes furred with excrement to a thickness of nearly three-eighths of an inch; I have never seen a corresponding deposit in a pipe of good slope where the current was direct. This latter point is rather one of curious interest than of practical value--certainly from the physician's point of view. Even in original construction it is rarely possible to give soil-pipes other than a practically vertical course as they pass from one story to the next. Indeed, the physician need not trouble himself to consider the question of the size or of the direction of this main channel. He will often find occasion to criticise the use of unduly large waste-pipes from single vessels; as, for example, two-inch pipes leading from bath-tubs; two and a half-inch pipes leading from laundry-tubs; and three-inch pipes leading from kitchen-sinks. Where reconstruction is to be undertaken, he may with advantage exert himself to secure in these lateral waste-pipes a diameter never exceeding one and a half inches, and from kitchen- and pantry-sinks, whose outflow is loaded with grease, preferably not exceeding the diameter of one and a half inches, with traps of even a little less size. Where several vessels lead into the same waste-pipe these small diameters may increase the tendency to the emptying of the traps by siphonage, but if proper mechanical traps are used for baths, wash-bowls, and laundry-tubs, and if ample flushing appliances are connected with kitchen- and pantry-sinks, the temporary removal of the trapping-water by siphonage may generally be disregarded. It will seldom happen that the removal of water will be so complete as to prevent the satisfactory closing of the mechanical valve by capillarity, even if it fails, in itself, to make a perfectly tight fit.

A favorite recent requirement of theoretical sanitarians, and one which has perhaps for business reasons been eagerly accepted by the plumbing trade, is what is called the "back" ventilation of traps; that is, the carrying of a vent-pipe from every trap in the house to a point above the roof. In my judgment, there is more to condemn than there is to commend this practice, for I believe that the more rapid emptying of traps by evaporation where they are not constantly supplied by frequent use, the dangers of accident to lead pipe, which is generally used for ventilating purposes, and the misapplication of a large outlay which might better be applied in other directions, constitute convincing arguments against this favorite new method of preserving the integrity of the water-seal. There are a number of traps which are closed by floating balls, or by balls bearing upon the outlet, which seem to be quite satisfactory and efficient. The worst waste-pipes, by far, are those of kitchen- and pantry-sinks which pass a large amount of hot grease. This soon cools sufficiently to congeal, and it attaches itself to the walls of the pipe, where it does congeal until the bore is reduced to what is barely sufficient to furnish the necessary limited water-way. Grease-traps of various forms have been invented with a view to retaining this obstructing material. After much experience with all of them that have been in general use, I have become convinced that the only satisfactory way to avoid the difficulty in question is to retain the outflow of the sink until a certain considerable quantity has accumulated, and until its grease has entirely {222} congealed, then to discharge the whole volume rapidly through a pipe of small calibre. This may be done with Carson's grease-trap by throwing in a pail of water to start a siphon action when the vessel has become filled to its overflow-point. It is more simply accomplished by a device of my own, wherein the whole outflow is retained by a plug at the bottom of a large vessel working after the manner of the plug of a wash-basin, until it is filled to the level of the sink, and then opening the outlet for its sudden discharge.

Good workmanship is as important as, if not indeed more important than, good arrangement. It seems a very simple proposition to say that all waste-pipes, whose office it is to carry foul liquids out of the house, should be made tight in material and in joint. It is a remarkable fact, however, that leaky joints in soil-pipes and in drains are by no means rare. Probably there are few houses, very few, in which they do not occur. The soil-pipe is put together by inserting the small end of each section into the bell at the top of the section below it, practically like putting the outlet of one funnel into the larger upper portion of another. There may be abundant space for leakage at every joint from the top to the bottom of the house, without there being the least show of the leakage of water. The foul air within the pipe may escape freely through a dozen openings, while the heavier liquid flow takes its easiest and most direct course downward from the point of one pipe through the bell of the one below. When we come to the horizontal run of the soil-pipe in the basement, if an imperfection of the joint occurs on the lower side there is an obvious drip, which continues at least until closed by rust. Similar imperfections in other parts of the joint would not be so manifested. It has recently been demonstrated that there is no safety in the construction of soil-pipes short of that absolute assurance which can be secured only by an efficient test. Plugging all the outlets of the soil-pipe and filling it with water, the slightest leak will be exposed.

However defective may be the condition of an iron soil-pipe, vertical or horizontal, it is perfection itself compared with the usual state of a drain laid under the cellar floor; and here is a point where the least experienced inspector of house drainage cannot be mistaken. Under all circumstances, at least in all work hitherto executed, he should demand as absolutely necessary that the drains under the cellar floor be removed, that the earth which has been fouled by the leakage of its joints and its breaks shall be taken out to the clean untainted soil below, and refilled with well-rammed pure earth or with concrete, the drainage being carried through a properly-jointed iron pipe above the pavement, and preferably with a fall from the ceiling of the cellar to near the floor at the point of outlet--in full sight for the whole distance. It sometimes happens that the necessity for using laundry-tubs or other vessels in the cellar makes the retention of an underground course imperative. When retained, the drain should be of heavy cast iron with most securely leaded joints tested under a head of several feet. When found to be tight and secure, it should not be, as ordinarily recommended, left in an open channel covered with boards or flags and surrounded by a vermin-breeding, unventilated and uninspected space, but closely and completely imbedded in the best hydraulic cement mortar. Its careful testing before this {223} enclosure is of course the only condition under which the work can be permitted.

Tightness of all waste-pipes being secured, the next point in order is their proper ventilation. A good deal has been said, and little has been proved, about the different effects on the human system of the gases of decomposition which have been produced in the absence of a sufficient circulation of air, and those produced where the ventilation and dilution are more complete. The probabilities of the case are, of course, entirely in favor of the latter condition, and it is accepted by all sanitarians as an axiom that all water-ways and all vessels in which organic decomposition, even the decomposition of adhering slime, takes place, should be ventilated as thoroughly as possible. Until about ten years ago nearly all waste-pipes were tightly closed at the top, and were shut from the sewer by a trap at the foot, allowing absolutely no communication between the outer air and the atmosphere of the pipe except as fresh air might be carried in through the water-seals of the traps at each end. At about that time it was becoming the general custom in the better class of work to carry a small vent-pipe, often only one inch in diameter, rarely more than two inches in diameter, through the roof of the house, closing it at the top and perforating it with a few inefficient holes. This had undoubtedly the effect of relieving the pressure on the atmosphere of the pipe caused by the filling of unventilated sewers with tide-water or storm-water, or by a sudden increase of temperature from the admission of hot water. Later, it was accepted as a universal rule, and it became a quite general practice, to carry the soil-pipe above the roof with its full diameter, providing its summit with some form of ventilating cowl. All this constituted not ventilation, but venting. Real ventilation was introduced only with the very recent improvement of admitting fresh air at the foot of the soil-pipe, so as to make a complete circulation from one end to the other--a circulation sufficient to produce, by the diffusion of gases, a very fair ventilation of lateral waste-pipes of moderate length. It is now coming to be understood that ventilating cowls, of whatever form, are an obstruction to the movement of air in the absence of wind, and that, as what is needed is never a vigorous current, but always a living one, these cowls had better be dispensed with. We have learned, too, that the most efficient means for increasing the flow of air through the top is to increase its diameter at the top, enlarging the highest length of a four-inch pipe, for example, to a diameter of six inches. With this arrangement, and with a foot-ventilation four inches in diameter opening at a point where it can never be obstructed by rubbish or by snow, there will be secured a condition perhaps more efficient in improving the condition of an imperfectly drained house than any other one thing that may be done.

I have sketched above, in a very hurried manner, the main outline of a system of house-drainage which may be accepted or which may be recommended by a physician with confidence of securing a good result. To go more into detail in technical matters would be out of place in a paper of this character. Before leaving this subject, however, it is important to call attention to the fact that what is recognized in our houses as sewer gas is in far greater degree the product of decomposition taking place within the house-drains themselves than the product {224} of decomposition in the distant sewer forced into the house through its connecting drain. It is emphatically a case of the beam in our own eye as compared with the mote in the eye of our neighbor. It is a rule which has exceptions, but they are few, that the contained air of the house-pipes is far worse than the contained air of the sewer; and the conviction is growing that the use of a trap to the main drain between the house and the public sewer is more often objectionable than advantageous. Such a trap always tends to check the flow of the drain and to induce deposits whose decomposition is objectionable. Wherever the abandonment of the trap is anything like universal the considerable ventilation of the sewer thereby secured brings its atmosphere to a condition which makes it not objectionable, and generally useful, as a source of movement in the air of the interior drain- and soil-pipe.

(a) Public sewers are more or less good or bad entirely according to their character and condition. As a rule, a well-flushed sewer which is used for no other purpose than the removal of foul waste, built on what is called the separate system, and automatically flushed at least daily, may be considered to be, if well laid and tightly jointed, absolutely safe. A public sewer of large size and of irregular construction, receiving not only household wastes, but the wash of streets as well, may be regarded at least as an object of grave suspicion. These general statements may be so far qualified by the character of the sewers of each class as to run very nearly together; that is to say, separate sewers, with leaky joints, irregular grades, defective alignment, insufficient flushing, and inadequate restriction as to the matters they are to receive, will be an intolerable and dangerous nuisance; on the other hand, a large brick sewer built in the best manner and of the best material, with sufficient fall and sufficient supply to maintain itself in a cleanly condition, is free from the serious drawbacks which usually attach to sewers of this class.

With sewerage as with house-drainage it is not worth while to attempt here to give anything like detailed directions for inspection and for reformation. It will suffice to call attention to this one broad and general rule: Every sewer or drain having for its object the removal of putrescible organic matters must be so arranged as to maintain itself in a condition of practically absolute cleanliness, without, as in the case of storm-water sewers, waiting for the flushing effect of storms, which often come only at long intervals, during which the worst condition of decomposition may be established. Whether the sewer be intended for drainage only or for both drainage- and storm-water, if it contains at any time deposits of any kind, it is defective--more or less so, of course, according to the extent and duration of the accumulation.

Although it should be rigidly insisted upon in every case that the sewer should maintain itself free from deposits, there will still be, unavoidably, a certain amount of foul gas produced by the decomposition of the matters coating its walls, and in order to dilute and to remove this, and perhaps in order to modify their original character, the most thorough ventilation is necessary.

Any sewer or other drain which at any time gives forth the odor of putrid decomposition is in bad condition and should be at once rendered inoffensive. So far as I know, there is no exception to this rule. I have met no conditions in towns of any size where absolute self-cleansing may {225} not be secured. It is worth while, however, to repeat here the statement made above, that sewer gas, in so far as it is a serious factor in connection with the drainage of houses, is the product of the interior pipes of the house much more frequently than of the public sewer in the street.

(b) The disposal of liquid wastes by irrigation, so far as this method is applied to the outflow of public sewers, is not of especial interest here, but an important modification has been made of the system of irrigation which is of the greatest consequence in considering the sanitary improvement of isolated country-houses, of hospitals, prisons, etc., and of houses in towns about which there is a small amount of available land. The process which has been found best suited to the purpose is the invention of the Rev. Henry Moule, the inventor of the earth-closet. He found it a serious drawback to the dry-earth system that it was incapable of taking care of the liquid wastes of the house. He devised a method of conducting the liquid into very shallow drains made with open-jointed agricultural drain-tiles, so porous in their character as to allow the liquid carried by them to escape at the joints into the soil, and thus get the benefit of its purifying qualities without the unsightly and often offensive process of allowing the liquid to flow over the surface. The first use made of this system was about 1866. Since that time its use has extended very considerably both here and in England, and many improvements have been made in its details, so that it may now be accepted as entirely satisfactory.

The process in its best development, as applied to the drainage of single houses, may be thus described, many of the appliances used being the subject of patents: The outflow from the house is delivered into a settling-basin or grease-trap of sufficient size to still the flow, to cause solids to settle to the bottom, and grease and other light matters to float at the top. The outlet from this basin is through a pipe having its inlet at some distance below its overflow-point; that is, at the level of the comparatively clarified liquid, below the grease and above the sediment. The outflow passes into another vessel known as a flush-tank, where it accumulates until it reaches the summit of a self-acting siphon. This height being reached, any considerable addition to the flow sets the siphon in action, and the whole contents of the flush-tank are discharged with rapidity into the drain beyond. The discharge completed, air is automatically admitted to the siphon, and no further flow can take place until the flush-tank has again been filled. The drain, of iron or vitrified pipes tightly joined, is continued to the edge of the ground prepared for purification. It here delivers into a series of open-jointed agricultural tiles, laid with their bottoms not more than ten inches below the surface of the ground. The total length of these tile-drains is regulated according to the discharging capacity of the flush-tank, with a view to their becoming entirely filled at each discharge. Within a short time after the flow has ceased the liquid has all left the pipes and entered the soil, its impurities being retained and its filtered water settling away into the porous or artificially drained ground below. During the interval between the discharges of the flush-tank, a day or more, the process of purification (oxidation) of the retained impurities goes on in the soil, and its thorough aëration prepares it to purify the next discharge. This method of {226} disposal is now employed in connection with hundreds of houses, and its use, which has in some cases continued for a dozen years, is constantly increasing. Its application implies a certain amount of fall, but this amount need not be great. The discharging height of the tank need not be more than twelve inches. The main outlet need not fall more rapidly than at the rate of 1 to 300, and the absorption-drains ought not to fall more rapidly than at the rate of 1 to 600. If the tank can be built on the top of the ground, an average surface fall of 1 to 400 can usually be made to meet all the requirements. Where waste matters are to be removed from cellars and basements below the level of the ground, a greater fall is necessary, or the wastes which are there collected must be thrown to the tank by pumping or otherwise.

Where there is a bit of grass-land a little removed from the house (and from sight), it answers a perfectly satisfactory purpose to dispense with the absorption-drains and to deliver the main outlet directly on to the surface of the ground. The effect in both cases is entirely different from what it would be were the flow of the drains not regulated by the use of the flush-tank. The moment we have a constant slight discharge, either on the surface of the ground or into the absorption-drains, we establish a condition of constant saturation which leads to the over-fouling of a small area, which is rarely if ever purified by aëration. For an intermittent discharge some form of flush-tank is an absolute necessity. It is often found in practice, where the flow from the house is considerable, that the discharge of the house-drains into the settling-basin produces such an agitation of its contents as to set in motion and to carry into the flush-tank bits of paper partly macerated, grease, etc. This has been met by a recent improvement, which consists in building a transverse wall in the settling-basin, which checks the current from the house-drain and causes the flow from the house side of the wall to pass over its top in a thin small current which does not materially agitate the contents of that part of the basin from which the outflow pipe is fed.

(c) The cesspool is still the chief reliance of the world at large. There is nothing to be said in its favor save what may be based on the old adage that "what is out of sight is out of mind." There is everything to be said in its condemnation, whether we regard its contents as a great mass of putrefying and infecting filth, as the source of oozings which travel through crevices of rocks, through layers of gravel, through seams in clay, or through lighter soils into and under cellars and into drinking-water wells and defectively constructed cisterns, or as an ever-active gas-retort supplying the pipes of the house with the foulest products of putrefaction. It is in all respects and under all circumstances a curse, unless placed far away from the possibility of tainting the air we breathe or the soil over which we live, or from which we or others take our drinking-water, and even then it had better be abandoned.

The simple drainage of the soil involves a question of the greatest importance. If the ground under the house or about it is at any time, unless perhaps immediately after heavy rains, saturated with moisture, we have to apprehend a condition of insalubrity more or less serious in proportion to the degree of saturation and the degree of foulness with which this is associated. The drainage requirements of land outside of the house are less easily determined, but it requires nothing more than a casual {227} examination of the cellar in ordinarily wet weather to determine whether or not an improvement of its soil-water drainage is necessary. If it is at such times wet, or even persistently damp, thorough drainage is demanded; and it is only necessary to say that this should be secured by some process which can under no circumstances bring the air of the cellar into communication with the air of a sewer or foul drain.

* * * * *

I have purposely abstained in the foregoing remarks from invading the province of the physician or the physiologist by discussing the influence of bad drainage on the health of those living subject to it. It may safely be assumed that physicians who care enough about the subject to interest themselves in investigating the condition of local or general drainage have convictions concerning it which could not be strengthened by the opinion of one belonging to another profession. The assumption is also confidently made that no intelligent medical man will hesitate for a moment to accept the dictum that the site of the house must be dry, and that it and its neighborhood must be entirely exempt from the influence of foul organic decomposition.

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GENERAL DISEASES.