Chapter II: Part 2

If a stream of pure water is available at a sufficient height, it may be led directly to the reservoir, or its current may be used to drive a water-wheel sufficient to do the pumping. In a majority of cases there will be found at no great distance a stream capable of supplying the water needed throughout the dryest season of the year, but not entirely free from organic impurities. In such cases it is often feasible, by excavating a filtering sump or pump-well at a little distance from the side of the stream, and at a sufficient depth below the level of its bed to secure a supply tolerably purified by filtration through the intervening earth. The distance at which this sump should be placed from the bed of the stream will depend on the character of the soil. The more porous this is, the greater should the distance be. This question as to the source from which the water is to be taken is one which, more than any other, calls for experienced judgment.

Frequently the conformation of the surrounding country is such that, even where there is no constant stream, it is possible by the construction of dams to pond an amount of water, to be furnished by surface washing, sufficient to supply the demands of the longest drought. In this case, as in all others where reservoirs are used, it is important to have a good depth of water, and not to allow, even toward the edges, any considerable shallow area. So far as possible, the depth should be everywhere great enough to prevent vegetation, and in all the shallower parts the surface soil should be entirely removed. As a rule, there should be a depth of at least fifteen feet of water, except near the very edges of the pond, and as much more than this as circumstances will allow.

The distribution of water for private use is a simple question of construction; but, as a matter of taste, too vehement a protest cannot be entered against the common misconception as to what is desirable in the way of public fountains. An instance in point is furnished by the public drinking-fountain in Newport. Some years ago there stood at the foot of the Parade a grand old stone bowl, hewn out of a solid block of granite, and filled by a pipe leading from a copious spring. This was a good, sensible, substantial drinking-trough, perfectly adapted to its use, unpretending and handsome. Later, a public-spirited gentleman, desiring to leave a monument of his regard for the city, gave a considerable sum to be used in providing a suitable drinking-fountain at this point. Those who had the control of the fund lacked either the good taste or the courage to refuse to expend it. The result is that this granite horse-basin--one of the best of its sort--has been removed to an obscure position; and there has been erected in its place a wretched cast-iron combination of bad architecture and bad statuary, such as form a conspicuous defacement of the public squares in Philadelphia, where they serve the double purpose of furnishing water to the people, and advertising a cheap clothing establishment. The one compensation for the violation of good taste inseparable from these constructions is to be found in the fact that they must, sooner or later, lead the public to realize the absolute unfitness of cast iron for monumental and decorative uses. With the artistic influences which are now so active in the instruction of the American people, it is not perhaps unreasonable to look forward to the day when all of these piles of pot-metal shall be relegated to the scrap-heap, and when less offensive fountains shall take their place. We may even hope to see the iron statue and its stove-like support which supplies water to the horses of Newport condemned to the foundry, and its solid old predecessor restored to the position which it ornamented for so many years.

A wide margin may be allowed for the exercise of taste in the arrangement of village fountains; and where private munificence enables the expenditure of a considerable sum, a good amount of exterior decoration may be admissible: but it should always be borne in mind that so much of the outlay as is needed for the purpose should go to secure a good artistic design. Especially should the use of cast iron be avoided, as being from every point of view, and under all circumstances, whether in the shape of cast-iron dogs or deer, or attempts at the divine human form, absolutely and entirely inadmissible for artistic uses. Better a dug-out log horse-trough, overflowing through a notch in its side, as an ornament to the best-kept village green, than the most elaborate pitcher-spilling nymph that was ever cast in an iron-foundry. So far as the mere construction work of public drinking-fountains and horse-troughs is concerned, not much need be said except in connection with the overflow. In cold climates, there is apt to be from all such structures a spilling of water which covers the ground for some distance with ice. This may be avoided by carrying the overflow by a vertical pipe descending through the body of the water by some well-protected channel directly into a drain in the ground, at a depth beyond the direct action of frosts. If the stream is constant, this depth need be nothing like that to which frost penetrates into the soil,--for the constant movement of the water will prevent its freezing, even if covered only a foot deep, though to something more than this depth it will be desirable to have the metal pipe enclosed in a larger pipe of earthenware, giving a space of enclosed air.

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Where there is no public supply of water, it is better in most cases (considering the nearness of wells in villages to cesspools and privy-vaults), to depend entirely upon cisterns. In our climate, where rain is abundant during a considerable portion of the year, the water falling upon the roof of any house, if properly collected and stored, is ample for the whole supply of the family which that roof shelters. This water as it falls is ordinarily free from any impurity that can affect its taste, and from every source of serious fouling; though, after a long-continued drought, it is well to divert and discharge upon the surface of the ground the first ten minutes' flow of a shower, so that the impurities of the air and the dust of the roof may first be removed. After this first dash, lead to the cistern all that follows. Even with this precaution, the water will be more agreeable for use if filtered. There are numerous systems for making filters in cisterns, but no other is so simple nor so durable and satisfactory as the separation of that part of the cistern from which the suction-pipe leads by a wall of brick and cement. It is simply necessary to build a wall of brick set on edge (two and a half inches thick), so as to include about one-quarter of the area of the bottom, sloping it back so as to terminate against the side of the cistern at a height of from four to six feet. This wall should be so well cemented at its joints that water can only pass through the material of brick, and for strength its form should be slightly bulging. A wall of this sort, measuring say six feet at its base, and rising to a height of six feet at its highest point, will transmit an amount of water sufficient to supply the demand of the most constant pumping that any domestic use can require.

SQUARES AND PUBLIC SPACES.

As a rule, the open spaces in a country village are subject to no other criticism than that of neglect; but the exceptions are not rare where an attempt at improvement has resulted in a sort of cemetery look that gives any thing but a cheerful, pleasure-ground aspect.

There is not much danger that persons who are enthusiastic for the improvement of the town in which they live will err on the side of too great simplicity. The public squares and parks of large and wealthy cities are regulated and maintained at great cost and under skilful and artistic management; and they cannot fail to strike country visitors as being in all ways desirable. So indeed they are. They are a chief element of the city's beauty, and, from an aesthetic point of view, their influence is the best to which its people are subjected. But their beauty and their aesthetic influence are both the result of a well-directed expenditure of large sums of money. It is quite natural that an enriched manufacturer or merchant, proud of his native village, should be ambitious to perpetuate the memory of his benefaction by providing for some corresponding decoration of its public green, and that he should attempt to reproduce there, on the smaller scale proportionate to the circumstances, the sort of magnificence that he has seen in the city park. If left to his own sweet will,--as he often is if he is willing to spend money for the public benefit,--he will, unless a rich man of the rarer sort, succeed only in producing a conspicuous imitation.

A park-railing of artistically-worked wrought-iron will be represented by a cast-iron substitute of much more elaborate device; and there will probably be "piled on," here and there, an amount of cheap ornamentation which at the first glance will have a certain imposing effect. In the matter of planting there may be an amount and variety of foreign shrubbery and sub-tropical plants, which, under proper care, would be of great value and beauty, but which, with the neglect to which they are doomed in their village home, are quite certain to abort. In fact, we may expect to see, what indeed we may now see, in painful degree, in many of our smaller towns, a halting attempt at the outside show of the city park, which, in the absence of those elements of artistic selection and appropriateness to the conditions which are to prevail, develop, as time goes on, into an ignominious failure.

The trouble is, that, in all expenditures of this sort, we are apt to begin at the wrong end. In the making of a park, every step that is taken, whether the park be large or small, is a costly one; and, if taken in their reverse order, every step is a wasted one. The chief reason why the final decoration of a city park is so satisfactory is that it is only the crowning work of many processes which have had the best and most careful attention from the outset. The wrought-iron grille, the architectural fountain, the bronze statue, the delicate trees and shrubbery, and the smoothly-finished walks and drives, depend for their success upon a vast amount of costly fundamental work, and a provision for constant skilful care, which have cost a deal of money, and which look to a large permanent outlay. The elaborate fence must stand on no unstable foundation; the fountain must be only the ornamental central point of artistic and well-kept lawns and approaches; the statue must stand amid appropriate surroundings; and all but the simpler native vegetation must have its suitable soil, and be insured its needed protection and care at all seasons. The degree to which these more ornamental features may be given to the village green with any hope of satisfaction will depend almost entirely upon the thoroughness with which it has been prepared to receive them. Could the enthusiastic members of the improvement association be brought face to face with the cost that is needed for quite hidden fundamental work in order to prepare their green for the more elaborate artistic decoration, they would be deterred at the outset from attempting any thing so ambitious. Could they know the cost of the mere work of grading and subsoil cultivation, under-draining, manuring, laying the deep foundation for foot-paths, and securing that perfect growth of grass without which all park-like ornament is robbed of half its value, they would set their faces resolutely against all propositions on the part of public-spirited citizens to veneer their unprepared grounds with misplaced exterior adornment.

If money enough can be provided to do the work thoroughly well from its very foundation, then of course nothing more is needed than that its direction be placed in accomplished hands; but unless this is fully assured, if--as is nearly always the case,--economy is the first thing to be considered, then the rule of action is fully stated in two words, _simplicity_ and _thoroughness_.

Avoid all fantastic ornament, and all decoration of every sort, that would be appropriate only to work of a more complete and substantial character. Let whatever is done be done in the most thorough way. If the ability is only enough to secure good grass, then do every thing that is necessary to furnish the best conditions for the growth of grass, make suitable provision for its care, and attempt nothing further. Good lawn-like grass surfaces, crossed only by foot-worn pathways over the turf, will be more beautiful and more satisfactory than will poor grass and cheaply made and ill-kept walks.

If something more than securing the best grass is possible, then let the next expenditure be in the direction of paths, applying to the construction of these the principles set forth in what has hitherto been said about sidewalks. In the case of level walks, with imperfect means of drainage, it is often desirable to secure the better foundation that is given by filling in to the depth of a foot or more with small stone.

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Whatever may be the natural character of the soil, unless always well drained by a porous subsoil, the first step toward establishing a good lawn is to secure perfect underdrainage. Establish a good outlet at the depth of three and a half or four feet below the surface at the lowest point of the area to be drained, and then, selecting the necessary lines for main drains, lay out parallel lines (thirty feet apart at a depth of three and a half feet, or forty feet apart at a depth of four feet) to include the whole area, and on these lines lay well-constructed drains of small open-jointed tiles. Cover these tiles with the most compact earth that has been excavated, and, after filling to a depth of one foot, tramp or ram this earth tightly. Then fill the rest of the trench, heaping over the lines any excess of material that may need the settling effect of heavy rains to work it into place.

The next step is to reverse or thoroughly mix the whole soil to a depth of at least fifteen inches. This work can be completely done only with the aid of hand-shovelling, but the aid of the plough will greatly facilitate it. Its purpose is to secure such an admixture of the organic matter of the surface soil with the more compact material of the subsoil as will make it sufficiently porous and fertile for the easy penetration of roots. It is best that this work should be done in autumn; and, if the land is level, that the freshly raised subsoil should be left exposed in its rough and lumpy condition--without harrowing--to the frosts of winter. If washing is to be apprehended, then sow the ground thickly with rye, harrowing in the seed only roughly. If the seed is sown early enough, the growth will be sufficient to protect the surface from washing. During the winter, let the whole surface be heavily covered with stable-manure,--the more heavily the better, as there is no limit to the amount of coarse manure that may with advantage be used for the establishment of permanent grass. In the spring, as soon as the ground is dry enough to work easily, plough in the manure with as shallow furrows as will suffice to cover the most of it; then harrow repeatedly, bringing the surface to as true a grade as possible, and sow it heavily with a mixture of Rhode Island bent grass, Kentucky blue grass, and white clover. As soon as the seed is well sprouted, showing green over the whole ground, roll the area repeatedly and thoroughly until it is as smooth and hard as it is possible to make it. As soon as the grass has attained the height of three inches, let it be cut with a lawn-mower, and let the cutting be repeated at least weekly throughout the season of rapid growth, and as often as necessary until the end of autumn.

If paths are to be made, it will simplify matters to make them after the grass has become well established, supposing only a good surface footway of ashes or concrete to be needed; for the small amount of excavation necessary under either of these systems may be scattered over the grass spaces without injury. But if the more thorough system is adopted of underlaying the walk with a foot or more of stones, then the work, except the final dressing of gravel or ashes, should be done in the autumn, or, in any case, before the final preparation of the soil for seeding.

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Concerning trees and ornamental shrubbery for parks and open spaces, it is not possible to give detailed directions here, beyond recommending, as in the case of roadside plantations, that, unless the work is to remain permanently in the charge of an experienced gardener, with the necessary appliances for the care and protection of the more delicate specimens, the arrangement and the selection should be confined to the more hardy and vigorous trees and shrubs which experience has shown to be adapted to the climate and soil of the locality.

For roadsides, and largely in parks and village greens, the world offers no tree that can compare in dignity and grace with the broad-spreading American elm; though, for the sake of variety, and for the sake of an earlier effect, many other trees may be added.

VILLAGE SANITARY WORK.

It is a recently recognized but an old and universal truth, that human life involves the production of refuse matters, which, unless proper safeguards are taken, are sure to become a source of disease and death. The danger is not confined alone nor chiefly to that element of household waste which is most manifestly offensive, but in almost equal degree to all manner of organic refuse. It is true that faecal matters are often accompanied by the inciting agent of the propagation of infectious diseases. For convenience, and as indicating the more probable means for disseminating infection, we may call this agent "germs." It has not yet been demonstrated with scientific completeness that a disease is spread by living germs whose growth in a new body produces a corresponding disorder; but all that is known of the circumstances of infection, and of the means for preventing it, may be fully explained by this theory. Typhoid fever, cholera, epidemic diarrh[oe]a, and some other prevalent diseases, are presumed by the germ theory to be chiefly, if not entirely, propagated by germs thrown off by a diseased body. So far as these ailments are concerned, there is therefore a very serious element of danger added in the case of faeces to the other evil effects which are produced by an improper disposal of any refuse organic matter. That any one or all of these diseases can originate from the decomposition, under certain circumstances of faecal matters, is not clearly determined. There is, however, good reason for believing that one common effect of the gases arising from improperly treated matters of this kind is to debilitate the human system, and so to create a disposition to receive contagion, or to succumb to minor diseases which are not contagious.

The same debilitating effect and the same injurious influences often result from the neglect of other organic wastes. The refuse of the kitchen sink is free from faecal matter; but it contains, in a greater or less degree, precisely the kind of organic material which has gone to make up the more offensive substance. If its final disposition is such as to contaminate the water that we drink or the air that we breathe with the products of their decay, the danger to life is hardly less than that from the decomposition of faecal accumulations.

It is proposed now to set forth, in the simplest way and without much discussion of principles (which may be studied elsewhere), the methods and processes by which village households and communities may be protected against the influences that come from an excess of soil-moisture, from damp walls, and from imperfect removal or improper disposal of organic filth.

We will assume that a village has a water supply sufficient to admit of the use of water-closets in all houses, and to furnish a good flushing for kitchen sinks, &c. A necessary complement of this work--indeed, it should properly precede it--is the establishment of a system of sewers by which all of this liquid outflow may be carried safely away. It would be out of the question in a small or scattered community, especially where roadways are unpaved, to establish any system which should include in its working the removal of surface water. The moment we undertake to make sewers of sufficient capacity to carry away the storm water of large districts, then we enormously increase the scale and cost of the work.

So far as the removal of house sewage alone is concerned, the work need by no means be very costly. If a tolerable inclination can be given to the line of sewers,--say a fall of one in two hundred,--a six-inch pipe will have a capacity quite up to the requirements of a village of two thousand inhabitants using one hundred gallons of water per day per head. It will, however, be safe to use a pipe of this size only when it is true in form and carefully laid, so that there shall be no retarding of the flow at the joints from the intrusion of mortar, or any other form of irregularity. Unless the joints are wiped quite smooth, the roughness remaining will serve as a nucleus for the accumulation of hair, shreds of cloth, and other matters which will hold silt and grease, and form in time a serious obstruction. Nothing smaller than six-inch pipe should be adopted for a street sewer. Unless the work is to be most carefully done, for all but the branch lines, for a population of five thousand, or less according to the fall of the sewer, it will be safer to use eight-inch pipes. These pipes must be laid with great accuracy as to grade and direction. All corners should be turned with curves of large radius and regular sweep, and with an additional fall to compensate for the increased resistance of curves. The weight of the pipe should not be supported upon the sockets (see Figure 3), partly as a question of strength, and partly because any irregularity of form or thickness of the socket would change the inclination of the sewer. The bottom of the trench being brought exactly to the required grade, let there be dug out a depression greater than the projection of the socket, the pipe resting upon its finished bottom for its whole length. (See Figure 4.) Too much care cannot be given to the thorough filling with cement of the space between the socket and the pipe inserted into it; the whole circle being well flushed and wiped, so that there may be no possibility of leakage.

The objection to leakage is twofold: sewage matters escaping into the soil might contaminate wells and springs; and it would also rob the flow through the pipes of water needed to carry forward the more solid contents. The continued efficiency of these small drains for carrying away the solid or semi-solid outflow of the house is dependent very largely upon the presence of sufficient water to create a scouring current. While eight-inch pipes are admissible as a safeguard against imperfect laying, they are liable to the grave objection, that, where the service to be performed is greatly less than their capacity, the stream flowing through them will not be sufficiently concentrated to carry forward the more solid parts of the sewage. Up to the limit of their capacity, six-inch pipes properly laid are greatly to be preferred, as insuring a deeper stream which will more generally attain the velocity of three feet per second, needed to move the heavier constituents of the sewage. The difference in cost between six-inch and eight-inch pipes will be sufficient to cover any extra cost of the most careful workmanship. However much attention may be given to the cementing of the joints, it will be impossible to prevent the running into the pipes of a certain amount of mortar; and the workman should have a swab or a disk of India rubber of the exact size of the bore of the pipe, with a short handle attached to its middle, to draw forward as each joint is finished, and so scrape away any excess of mortar before it hardens.

Wherever it is, or may probably become, necessary to attach a house-drain or land-drain, there should be used a length of pipe having a side branch, oblique to the direction of the flow, to receive such connection. The location of these branches should be accurately indicated on the plan; and they should be closed with a flat stone or a bit of slate, well cemented in place.

It will at times be necessary to use larger conduits than even an eight-inch pipe. Up to a diameter of fifteen inches, it is cheapest to use pipes, but for eighteen inches or more, brick-work is cheaper; and at that size--a considerable regular flow of water being insured--the slight roughness of brick-work offers no serious objection. The use of oval or egg-shaped sewers will rarely be necessary under the circumstances that we are considering; but there may be exceptional conditions where the covering-in of a brook, or storm-water course, cannot be avoided; and in such cases the volume of water may vary so greatly that there will at times be a mere thread of a stream, and at times a torrent. Here the oval form is the best, as concentrating a small flow within a narrow and deep channel, and still giving the capacity needed for exceptionally large volumes. All bricks used for sewers, man-holes, &c., should be of the very hardest quality, and true in form. The general rule is to be kept in mind, that the thickness of the wall of a brick sewer should not be less than one-ninth of the inner diameter; that is to say, that up to a diameter of three feet the thickness of the wall should equal the width of a brick,--four inches. This applies to circular sewers only: the oval form, being less strong, calls for a wall of a thickness equal to one-eighth of the largest diameter.

Connecting drains leading from houses to the sewer are to be made at private cost; but they should be made in accordance with plans furnished by the public authority, and by a workman acceptable to that authority.

The householder might be permitted to take the responsibility of the finishing of his drain, but for the fact that the working of the public sewer calls for the largest amount of water in proportion to the amount of solid matters that it is possible to secure, and thus makes it imperative that this drain should be absolutely tight, so that the liquid parts of the house outflow shall not trickle away through its joints, leaving only the more solid parts to flow into the public sewer.

Properly graded and smoothly jointed, a four-inch pipe will carry more water than even the largest boarding-house or country hotel is likely to discharge. There is, however, a tendency in all house-drains to become filled in the early part of their course by the accumulation of grease and solid matters caught in the grease. Where no form of grease-trap is used, there is a certain argument in favor of the use of six-inch pipes for the upper part of house-drains. The use of a grease-trap, however, should always be insisted upon; and with its aid these obstructing matters will be retained, and the outflow may be perfectly carried by a four-inch pipe.

So far as the public sewer is concerned, it makes little difference what is the size of the house connection drain through the greater part of its course; but the junction with the sewer should, under no circumstances, where six-inch sewer-pipes are adopted, be more than four inches. I should even insist on four-inch connections with an eight-inch sewer. Through neglect, or by reason of improper management, many kinds of rubbish find their way into house-drains; and a four-inch opening will admit as many of these into the sewer as it will be able to carry away. If, by reason of bad construction or neglect, an obstruction is to be caused at any point, it should be in the drain, which the person responsible for it must cleanse or repair.

The grease-trap referred to above may be any form of reservoir which will retain the flow from the kitchen sink until it has time to cool, when its grease will be solidified, and will float at the surface. The outlet from this trap should be at such a distance below the surface of the water, that there will be no danger of its floating matter passing in with the discharge. A very simple device for this purpose is shown in Figure 5. From a trap of this sort the flow is constant whenever additions are made to its contents.

A, Receiver; B, grating; C, ventilator; D, siphon; F, entrance to drain; I, delivery from sink.]

Figure 6 shows the invention of an English engineer, Mr. Rogers Field, which has the effect of retaining all of the outflow from the kitchen sink until it is entirely filled,--say thirty gallons. When filled, any sudden addition of a few quarts of water, as from the emptying of a dish-pan, brings into action a siphon whose entrance is near the bottom of the tank; and this siphon rapidly discharges all of the contents above its mouth in a flow having sufficient force to carry forward not only any solid matters which it may contain, but also any ordinary obstructing accumulations in the drain below. The soil-pipe, carrying the discharge of water-closets, should not be delivered into the flush-tank, but at a point farther down the drain, so that any solid matter it may deposit shall be swept forward by the next action of the flush-tank. The more often the flush-tank is filled, and the greater the proportion of its water to its impurities, the more efficient will be its action. Therefore the slop closet waste leading from the upper story, and even the outlet pipes of bathing-tubs, may with advantage be delivered into it.

Although the flush-tank may receive no faecal matter, and even though the housemaid's sink may not deliver into it, it will contain in the discharge from the kitchen alone an amount of organic matter which will produce offensive and dangerous gases by its decomposition. To provide for the safe removal of these gases, a ventilating pipe should be carried up to some point not near to any window or chimney-top.

From the time the sewers are ready for service no accumulation of faecal matter or other organic household waste should be allowed to remain in the village. All old vaults and cesspools should be filled with earth, and disinfected by the admixture of lime with the upper layers of the filling. The use of water-closets in all houses should be made imperative; and the construction and arrangement of soil-pipes and of all outlets should be regulated by the health authorities.

It is not worth while here to discuss the details of the construction of water-closets and other interior plumbing work, except with reference to soil-pipes and such drains as may deliver the outflow of soil-pipes to the public sewer. The soil-pipe should be of cast iron, carefully jointed with lead, not less than four inches in diameter, and carried by the straightest course possible up through the roof and generally higher than the ridge-pole. Its open top must not be near any window, and if within ten feet of a chimney it should be at least one foot below the level of the top of that chimney. There should be no trap in the soil-pipe, and no trap in a private drain between the outlet of the soil-pipe and the sewer. The reasons for this rule are twofold:--

1. No matter what amount of water may be used for flushing out the soil-pipe, its sides will always be more or less coated with organic filth; and, however slight this coating, there will be a certain amount of decomposition. The decomposition of all such matters must be rapid and complete, not slow and partial. A necessary condition of complete destructive decomposition is an abundance of atmospheric air to supply the oxygen which complete decomposition demands. If the soil-pipe is closed at its top, or if it is obstructed by a trap in the lower part of its course, there can be no such circulation of air as safety requires.

If there is an opportunity for the free admission of air from the well-ventilated sewer to feed the upward current almost constantly prevailing in a soil-pipe open at both ends, the gases resulting from the decomposition will be of a different and less injurious character than where the air is confined,--and by the mere volume of air passing through the pipe they will be so diluted that even were they originally poisonous their power for harm will be lessened.

The gases formed by the decomposition of organic matter in the sewer itself, or in the soil-pipe, have a certain expansive force which is greatly increased by the elevation of temperature, caused, for example, by the discharge of hot water into the pipe or sewer. If the soil-pipe is open at its upper end this expansion will be at once relieved; but if the top of the pipe be closed there will always be danger of the forcing of the feeble barrier offered by the ordinary water-seal trap of a branch pipe leading from a wash-basin or sink. Then, too, the sealing-water of the trap readily absorbs any foul gases presented at its outer end, toward the soil-pipe, and gives it off in an unchanged condition at the inner or house end. Such traps retard, but do not prevent, the entrance of sewer gases into the house. Water-seal traps which are unused for any considerable time are emptied by evaporation, and thus open a channel through which the air of the soil-pipe may find its way into the house.

It is usual in modern plumbing to relieve the pressure of gas in the soil-pipe by what is called a "stench-pipe." This is a pipe from one to two inches in diameter, leading from the highest point of the soil-pipe to the outside of the roof, where it is bent over to prevent the entrance of foreign matter, or is closed at the top and perforated with holes to allow the gas to escape. This small stench-pipe is inadequate for the necessary work. It is very important that there be the freest possible channel for the movement of air; and nothing will suffice for this save the continuing of the pipe, at its full size, to its very outlet. Indeed, angles and bends in a pipe by increasing friction form a serious obstruction.

The arrangement of the soil-pipe here indicated, although excellent and efficient, is susceptible of further improvement by the use of a ventilating cowl or hood at its top. There are many forms of such cowls in use which are effective whenever there is a sufficient current of wind; but most of them require a certain force to bring them into action, and when this force is absent they usually retard the flow they are intended to increase. This is true of a recent invention known as "Banner's ventilating cowl," which so long as the wind blows is a most effective device. When the air is perfectly still, however, it offers by its curved air-way a certain resistance to the current, and in the case of baffling winds and flaws the air may blow directly into its opening.

Among the various inventions of this sort nothing seems so free from objection as the old arrangement known as the "Emerson" ventilator, shown in Figure 7. This gives a straight outlet, protected by a disk far enough above it not to prevent its delivery of air; and it becomes an effective suction cowl, with the least movement of the wind from any side or from above or below. No eddy caused by the angles of gable roofs can give it a backward draught; and if a pipe armed with it be held toward the strongest gale a puff of smoke blown into its other end will be instantly drawn through. As the patent for this invention has run out, it is competent for any tinsmith to make it, and it is a common article of manufacture.

2. What is said above concerning the ventilation of the soil-pipe from end to end relates to the interest of the private owner. The interest of the public gives an equally strong argument in its favor. The sewer should be as far as possible removed from the condition of an "elongated cesspool." There must be no halting of its contents, and no deposit of filth or silt at any point. Within the shortest time possible, every thing received into the sewer must be passed on and delivered at its outlet. Still, however perfectly this may be accomplished, there will always be a certain adhesion of slime to the walls of the sewer; and this slime must always be in a state of decomposition, a constant source of offence and possible danger. The only way to avert this danger is to give the sewer such a thorough ventilation that the decomposition shall be rapid and safe, and that the resultant gases shall be at once diluted with fresh air.

This may be measurably accomplished by the simple ventilation of the sewer itself, through open-topped man-holes; but such ventilation is less effective in the case of small sewers than of large ones. In the case of either large or small sewers, it will be vastly increased if we compel every householder who makes a connection with the sewer, to carry a drain and soil pipe, nowhere less than four inches in diameter, from the point of junction with the main line to the open air above the roof. Where houses are near enough to make the use of a public sewer advisable, the aggregate of these soil-pipes, having almost constantly an upward current, will make such a draught upon the sewer, to be supplied by a downward current through the man-hole covers, as will maintain a perfect and continuous ventilation.

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Important as it is to secure the proper arrangement and construction of sewers and house-drains, it is still more important to provide for the safe disposition of the sewage.

We must begin at the outset with the understanding that all sewage matters not only are of no value to the community, but that it will cost money to get rid of them.

There is hardly an instance, after all the efforts that have been made, of the _profitable_ disposal of the outflow of public sewers. The _theoretical_ value of the wastes of human life is very great, but the cost of any method for utilizing them seems at least equally great. The question of cost is so much more important (to the community) than the question of agricultural value, that the practical thing to do is to make such disposition as will cost the least, while fully meeting the best sanitary requirements.

So far as village sewage is concerned, there are three means open for its disposal: to discharge it into running water or into deep tide-water, to use it for the surface irrigation of land, or to distribute it through sub-irrigation pipes placed at little distance below the surface of the soil. Experiments are being made with more or less promise of success in the direction of the chemical treatment of this liquid so as to purify its effluent water, and retain in a solid form, and in combination with certain valuable added ingredients, all of its undissolved impurities. None of these processes can as yet claim consideration in regulating public works.

The cheapest way to get rid of sewage is to discharge it into a running stream or into tide-water. So far as the community itself is concerned, this is often the best way; but there will very often arise the objection that the community has no moral or legal right to foul a stream of which others make use in its further course. Where the amount of water constantly flowing is very large, and where the discharge is rapid,--any given part of the sewage reaching the open air within a few hours from the time of its entering the pipes,--and where it flows in moving water for a considerable distance before reaching others who may have occasion to use the stream, no practical danger is to be apprehended. But where the sewage is more foul, more sluggish, or exposed in the open current for a shorter time, the danger may be serious. The pouring of sewage into tide-water is always admissible where floats show that there is no danger of a return and deposit of solid filth; but the delivery at all stages of the tide, in the immediate neighborhood of salt marshes and mud flats, and in land-locked harbors, is to be avoided.

Where an unobjectionable natural outflow cannot be provided, the irrigation of agricultural lands affords the best relief. The action of vegetation, the oxidation which takes in the upper and well-aerated layers of soil, and the well-known but not yet fully explained disinfecting qualities of common earth, are effective in removing the dangerous and offensive impurities, and in converting them into a more or less important source of fertility. Precisely how far this system may be available during winter, it is not easy to say. While the earth is locked with frost, there must be very little, if any, infiltration; but, as an offset, the action of a low temperature upon the sewage matters will clearly be antiseptic; and it is only necessary to provide against an undue washing away of the surface of the ground during thaws, and against the flowing of the sewage beyond the proper limits.

Generally in the neighborhood of villages it will be easy to find lands over which the delivery may be carried on throughout the year without objection. The sewer, or some form of covered channel, should lead far enough from any public road to avoid offence. From this point it may be led by open gutters to the land over which it is to be spread,--or rather through such a system of surface gutters as will enable us to deliver it at different parts of the field, according to the requirements of the crops, and so as to use fresh land at frequent intervals, leaving that which has been saturated to the purifying processes of vegetation and atmospheric action.

The gutters having been made, it is easy, by the use of portable dams,--of thin boiler-iron, like broad shovels,--which may be set in the course of the flow, to divert the current into any branch channel, or to stop it at any desired part of this channel. All the gutters having sufficient descent to lead the sewage rapidly forward, it is usual to set a dam near the far end of the gutter, and allow the sewage to overflow and run down over the surface until it has reached as far as the formation of the ground and the quantity of the liquid will allow it to spread. This portion having received its due amount of the liquid, the dam is moved to a higher point, and the overflow is allowed to spread over a second area. In this way, step by step, we irrigate all that may be reached by a single gutter. Then the moving of the dam in the main line turns the water into another gutter, and this is proceeded with in like manner. In practice it is found best to begin the overflow at the farthest end of the lowest-lying gutter, working back step by step until the higher parts of the field are reached. It would be better that there should be land enough to require the irrigation of any given area not oftener than once in one or two weeks. The amount required for a given population cannot be determined by any fixed rule,--so much depending on the amount of water used _per capita_, and on the absorptive character of the irrigated soil. In the case of villages, one acre to each five hundred of the population would generally be found ample.

There are several instances of the successful use of a much smaller area than is here indicated, by the use of intermittent downward filtration. The most noted success in this direction is that at Merthyr-Tydvil in Wales, a large mining town, where the allowance is only one acre to each two thousand of the population. There are two filter-beds of light loam over a gravelly subsoil thoroughly underdrained with tiles at a depth of six feet. One of these beds is cultivated with some crop like Italian rye-grass, which bears copious irrigation; and the other by some crop like wheat, which, in the absence of irrigation, will thrive on the fertility left over from the previous season. The volume of sewage is very great, but the action of the six feet of earth in removing its impurities seems to be complete; the water flowing out from the drains having been proved by analysis to be really far purer than the standard fixed by the Rivers Pollution Commission.

It is an important condition of this system that the sewage, where its quantity is small, shall be stored in tanks until a large volume has accumulated, and that it then be rapidly discharged over the soil. There is no objection to an actual saturation of the ground, provided the soil is not of such a retentive character as to be liable to become puddled, and so made impervious. The tanks being emptied, the flow ceases until they are again filled. During the interval, the liquid settles away in the soil, by which its impurities are removed. Its descent is followed by the entrance of fresh air, and the oxidizing action of this, accompanied during the growing season by the purifying effect of the growing crop, leads to an entire decomposition or destruction of all organic matters.

The third system--the distribution of sewage through irrigation-pipes laid at a depth of ten or twelve inches below the surface of the ground--has its efficiency attested by numerous instances in private grounds. I have adopted this system for disposing of the sewage of the village of Lenox, Mass., where there was no other means available short of cutting an outlet, at great expense, through a considerable elevation. This method is an extremely simple one, and is available in every instance where even a small area of land lying slightly below the level of the outlet is to be commanded. The arrangement of the sub-irrigation pipes is easily made: Suppose that in land having an inclination of about one in two hundred, occupied by grass or other growth, a trench be dug twelve inches deep, that there be laid upon the bottom of this trench a narrow strip of plank to insure a uniform grade, and that upon this plank is laid a line of common agricultural land-drain tiles, say two inches in diameter. However carefully these tiles may be placed, there will be at their joints a sufficient space for the leaking out of any liquid they may contain; the tiles being laid either with collars around the joints, or with bits of paper laid over them, to prevent the rattling in of loose earth during the filling. The excavated earth is to be returned to its place, well compacted, and covered with its sod. Suppose this drain to have a cross-section equal to three square inches, and a length of one hundred feet, its capacity will equal about sixteen gallons, or a half-barrel. If this amount of liquid be rapidly discharged into the drain, the inclination being slight, it will at once be filled or nearly filled for its whole length, and the liquid will leak away in tolerably uniform proportion at every joint along the line, and will saturate the surrounding earth. The plan adopted at Lenox, and recommended for all small villages which cannot secure a better outlet, is simply a multiplication of these drains to a sufficient extent.

A description of the manner in which the Lenox work is arranged will illustrate the adaptation of the system to its circumstances. As circumstances vary, the adaptation must be modified. (See Figure 8.)

The main outlet sewer delivers at a distance of about one-half mile from the last junction with a branch sewer. It is a six-inch pipe five feet below the surface of the ground, and it delivers into a flush-tank like that shown in Figure 6, but having a capacity of about five hundred cubic feet. This tank stands at the upper side of a field having an inclination of seven in one hundred. There is a branch from the main sewer, above the tank, supplied with a stop-cock, by which, in case of need, the sewage may be carried on down the hill without going into the tank. The outlet from the chamber below the siphon leads off in another direction down the hill, and has a stop-cock and a branch which will allow its flow to be diverted. The discharge of this diverted stream and the discharge through the branch of the main above the tank, both deliver into a horizontal surface gutter to be well grassed, and lying at the top of the land to be irrigated. By this arrangement, should repairs become necessary in the tank, the flow may be turned into the gutter; or, should it be desired for any reason to use the outflow of the tank for surface irrigation, the second branch outlet will deliver it into the same gutter, where, the outflow being uniform along the whole length of five hundred feet, the stream will pass in a thin sheet off on to the descending ground. The hill-side, immediately below the gutter, is brought to a true grade and covered with grass. As its inclination is much greater than would be admissible for sub-irrigation drains, these are laid _obliquely_ in parallel lines at intervals of six feet from one end to the other over the whole graded slope. These drains are connected at their upper ends with the direct outlet-pipe leading from the siphon chamber. They have an aggregate length of about ten thousand feet. The method of operation is as follows:--

The capacity of the tank is supposed to equal about two days' discharge, or about thirty-five hundred gallons; and the whole capacity of the drains is about half that of the tank, so that the rapid emptying of the whole volume into them will insure their being pretty thoroughly filled from end to end. This arrangement will provide for the saturation of the soil about once in two days, and will leave a sufficient interval between the periods of saturation for the thorough dispersal and aeration of the filth.

The extent to which this system will be interfered with by frost, it is impossible to say. This will probably be less than would be supposed, for the reason that the ground would often be covered with snow, and that the sewage will have sufficient warmth to exert considerable thawing influence. Whenever the discharge of the liquid through irrigation pipes is shown to have become obstructed by freezing, it will only be necessary to divert the flow, and turn it into the surface gutter to be distributed over the ground.

It is possible that in this case, as in the one which has been under my observation for six years past, there will be no interruption of the working because of cold; but, should the interruption become serious, I shall propose the planting of evergreen trees in parallel rows midway between the drains. The protection that would thus be afforded, both by the trees and by the drifting snow which they would gather, would probably keep the ground free throughout the winter. Incidentally to the chief advantage of this system, there will be, so long as the land is in grass, quite an addition to its product.

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