SIDEWALKS.
No one thing has more to do with the comfort of those living in country villages than sidewalks which are good at all seasons of the year. Those fortunate villages which are built on a gravelly soil, with a perfect natural drainage, need little more in this direction than such a conformation of the surface as will prevent water from standing on the footway when the ground is frozen. At all other times it sinks naturally away into the earth. It is much more often the case that the character of the soil or subsoil prevents a settling away of water, or that subterranean oozing from higher ground keeps the earth throughout the spring and autumn, and after heavy rains in summer, damp, and often sloppy. Wherever the ground is of such a character as to prevent the rapid sinking to a considerable depth of all excessive moisture, there is sure to be a disagreeable condition of the footway whenever the lower soil is locked with frost, and the surface is thawed. Even with the best drainage, natural or artificial, this condition will exist for a short time while frost is coming out of the ground; but with good drainage it is of so temporary a character as hardly to justify any expensive finishing of the surface, except perhaps in the case of the most frequented walks.
To overcome occasional sloppiness where the difficulty is not deep-seated, there is no cheaper nor better device than to dress the surface with coal-ashes. Indeed, if these are used to a sufficient thickness, they are practically as good as concrete or the best gravel. When first applied, they are dusty and unpleasant; but the first wetting lays the dust, and they soon settle to a firm consistency, and make a very pleasant walk, with the great advantage of being entirely barren, and preventing the growth of weeds and grass. If the ashes of a village are collected and screened, the cinders being used at the bottom, and the surface being smoothly dressed with the finer material, they will make as satisfactory walks, even where the use is considerable, as any other material. The color is unobtrusive, and the surface soon becomes hard enough to bear sweeping. Those who are more ambitious for effect may prefer a walk made of tar-and-gravel concrete; and this, if well made, is good, durable, and satisfactory. So far as the improvement association is concerned, it can find many ways for expending the difference of cost between ashes and concrete, which will accomplish a much more telling result.
If gravel can be obtained without too much expense, it may be used with excellent results to a depth of from one to three inches, according to the porosity of the subsoil,—more being needed where the ground is inclined to become soft. In using gravel it is best either to screen it, using the coarser parts below and the finer parts at the surface, or, after applying it, to add a thin layer of earth, barely sufficient to fill its spaces,—to "bind" it so as to give it a firm and solid consistency. Loose and rattling gravel makes a handsome walk to look at, but an unpleasant one to walk upon. Nothing is more agreeable than well-trodden, dry, root-bound earth, as where grass has been worn away by frequent use; but this becomes at once objectionable on being saturated with rain or moistened by melting frost.
FIG. 1.
It is a common impression, that all thoroughly good foot-paths must be dug out to a considerable depth, filled with loose stones, and dressed at the top with some good finishing material; but this is not necessary even for the best work. The great point is to secure a thorough draining of the sub-stratum, so that there shall be no rising of ooze-water from below, and so that the ground shall be free from such saturation as to cause heaving during frost. This condition may be secured by a suitable draining of the ground immediately under the walk, and by the use of a well-compacted and tightly-bound surface covering of such form as to shed or turn away rain-water. Figure 1 (p. 31) shows the cross section of a foot-path six feet wide on slightly sloping ground, where we have to apprehend an oozing of subsoil water from the land at the highest side. The centre of the walk is slightly crowning,—say one inch higher than the sides,—so that rain falling upon it will flow readily toward the grass-border at either side. To prevent the ponding of water at the sides when the ground is frozen, the surface of the walk at its edges should be well above the level of the adjoining ground; but it may be necessary under some circumstances to furnish, here and there, a channel or surface-gutter across the walk, to allow the accumulation at the higher side to escape. Rarely will deep gutters at the sides be necessary or desirable. If the walk is laid at a sufficient height to turn water on to the adjoining ground instead of receiving water from this, it will be easy to keep it dry. We will assume that the path in question is to be made over a tenacious clay soil, with a considerable oozing from the hillside,—the most unfavorable condition that can be found, especially in cold climates. The first thing to be secured is the cutting-off of the subsoil water from the hill. This may be done by digging a trench as narrow as possible,—six inches will be better than more, as requiring less filling material,—to a depth of three feet. In the bottom of this drain lay a common land-tile drain, with collars at the joints if these can be procured, and, if not, with a bit of paper laid over the joints to prevent the entrance of loose material, and to hold the pipes in place during construction. The ditch should then be filled with cinders, gravel, or coarse sand. If stones are to be used, they should be broken to a small size,—not more than one inch in diameter,—and the loose bits should be mixed with them in the filling. Very small interstices will be sufficient to allow water to pass freely through, while if large stones are used, with large interstices, there will be danger of a washing-in of earth sufficient in time to obstruct both the stonework and the tile. The smaller the tile, so long as it is sufficient for its purpose, the better; for lengths of five hundred feet or less, an interior diameter of an inch and a quarter will be sufficient; from this to one thousand feet, use an inch and a half bore. If possible, before exceeding this length, secure an outlet for the water in the roadside gutter or some other channel of exit. The tile-drain, at a depth of three feet, will remove all subsoil water from under the walk, and all that may be delivered into the loosely filled trench at its side. The loose filling of the trench should not be carried nearer than within six inches of the surface of the ground, and should be covered with fine and well-packed earth to prevent the entrance of surface-water which would soon carry in silt enough to stop its action. Whatever covering is adopted for the walk itself, it must be of such a character as to prevent any thing like a free admission of surface-water. Concrete will do this perfectly; and either ashes, or gravel dressed at the top with ashes, if well raked and rolled at the outset to a smooth surface, will soon become so bound together as to shed pretty nearly all rain falling upon it. The difference in cost between a walk made in this way, and one dug out for its whole width to a depth of two feet, and filled first with stone and then with gravel and a suitable surface dressing, will be very important; and it is safe to say that the cheaper will be at least as good and durable as the more expensive method. In all construction of sidewalks, whether public or private, regard must be had to the surface conformation, and some device must be adopted for preventing the flow of water upon the walk from the adjoining ground, and for the easy delivery of storm-water falling upon the walk itself.