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retain grades, in places, so heavy that a team is unable to haul more than half, or perhaps one-quarter, the load it can on all the remainder of it. Roads which are steep in the line of their axis are not only more severe on teams, but they are dangerous, and much more expensive to keep in repair. Various opinions have been expressed by engineers and essayists on this subject. Mr. H. F. French, of Boston, Massachusetts, in a very able paper on roads, contained in the report of this Department for 1866, says: “In view of every consideration, except drainage, the level line is probably the best; but, as drainage is essential, and, as will be seen when we come to consider the construction of roads, it is desirable to make them as flat as possible transversely, a slight slope in the length of them is found expedient. This slope should be one in two hundred, which is sufficient for drainage without injury by washing, and adds little to the draught."
A grade of one in two hundred is a very desirable one, so far as draught is concerned, but it is nearer level than is practicable on any considerable proportion of our country roads; and, as regards drainage, it will be of little service. Much lateral slope is objectionable, but we do not consider that a slope of one-quarter of an inch to one foot is so, while it is sufficient to provide lateral drainage, which is more efficient than longitudinal drainage. The widest track of country wagons does not exceed fire feet, and, with a slope of one quarter of an inch to one foot, the difference in the height of the wheels when tlie vehicle is on the side of the road, is but one and a quarter inch, and this is reversed in returning. It often occurs in rural districts that it is practicable to drive a large proportion of the distance on the summit of the road bed, where the vehicle will be on a level. It is next to impossible to prevent road surfaces from rutting to some extent, and,a - slope of one in two hundred” only, while it is so gentle that there will be no tendency to wash, will certainly keep surface water on the road-bed so long that much of it will be absorbed, which may be avoided in lateral drainage, without injury to vehicles, displacement of lading, or inconvenience to passengers. It is not practicable to give a rule for the exact amount of longitudinal grade of roads, as they are affected by so many circumstances. Primarily the best provision for business traffic should be considered paramount to all else, yet this has often to be modified by local circumstances, whether in regrading old roads or in locating new ones. In the latter, if the locality is mainly unsettled, and the probabilities are that the building sites will be most popular near the summits along the line of the projected road, the engineer should prospect contiguous lands, and so inodity the route that the necessary laterals may connect with the road by grades that shall be easy, safe, and inexpensive.
There has been a very general and striking change in the taste evinced in locating rural homes, country seats, and farm buildings, of late, to provide for which a corresponding change in the roads by which they are to be reached has become indispensable. Formerly, the popular site for rural buildings was under the lee of clerated ranges of land, near the streams, or springs at the base of hills, to accommodate which the public roads generally traversed the banks of streams, in which position the drainage of all the high lands must pass under or over them. The advantages of the modern system are numerous, and the disadvan. tages few. The salubrity of the high sites, the more extensive and pleasant view secured from the buildings, as well as from the summit or the hill-side road by which the buildings are reached, the reduction of cost of construction and maintenance of such roads, the superiority of thic grade generaily obtainable, as compared with those along the streams,
and the greater feasibility of securing dryness about the buildings, as well as of beautifying the landscape in their vicinity, are among the most prominent alrantages of the modern selections over the primitive. Some have urged as objections to the high sites, that they are bleak and cold, and that water is not convenient. The former objection is fully met in the inodern improved methods of building, and of economically generating and circulating heat; while, by the use of improved hydraulic apparatus, the supply of water is inade ample, and luxuries unknown in the old system are fully enjoyed.
Where objectionable grades, say of ten feet to one hundred, the hear. iest that should ever be tolerated, are unavoidable, the following instructions for construction and repair should be observed : Avoid short curves in the road; make the bed wider on the hills than on the plains, and especially in the curves. If the road runs along the side of a slope, grade the surface of the bed, so that all water falling on it shall be cast to the gutter on the upper side, as there is great danger of accident in icy times, if any portion of the bed has a lateral slope with the hillside. On such road provide low water bars across the road at intervals of thirty to forty feet. These bars should be placed obliquely, and should discharge all the water in the gutter on the upper side. If the gutter is disposed to wash, it should be paved, and the curb of the pavement on the road side set so low that water from the road-bed may low into the gutter the entire distance from bar to bar, instead of being required, as is frequently the case, to flow in the ruts of the road-bed until it reaches the bar, which it often overflows and washes away continuing to flow on the road until dangerous gullies are cut, requiring much expense to repair them. If the hill is long, sav one-fourth to half a mile, the water should be carried across the road in culverts, one hundred to one hundred and fifty feet apart. The best and cheapest common road culvert may be made of hard-burned terra cotta pipes. On hilly roads they are rarely required of more than eight to ten inches caliber. These pipes need no sleeves, or bells, nor any cementing of the joints; and are less expensive than the common stone culvert, even where the stones are at band. The capacity of the pipes, owing to the smoothness of their interior surface, is mucli greater than that of a stone culvert of the same area of cross section. The pipes should be burned like hard, red brick, and are then as durable as granite. The pipe culvert should receive the water from a shallow well, walled up with stones or bricks. This well should be in the line of the gutter on the upper side of the road. The water from the gutter should fall into the well over a flag on the wall of the well, and between two side walls, carried up with the other walls to a height sut: ficient for a proper opening, when the well and the opening in the upper side should be covered with a strong flag. This flag should orerlap the inner face of the wall of the well at the opening, at least one foot, that animals may not step into the well. This arrangement makes the upper end of the culvert sightly, secure, and free from all dangerous effects. The trench in which the pipes are laid should have a fall, so that the water from the culvert may be discharged upon a natural surface, as it will be less liable to gully it than an artificial bank.
STONES ON EARTII AND GRAVEL ROADS.
In preparing earth and gravel road-beds, all small stones, down to half the size of a hen's egg, should be removed from the surface soil, as the tendency is for them constantly to work up to the surface, where they are injurious to the feet of the horses, and to vehicles, wear and
Fig. 1.-Elevation of the grader c; oak plank, 3'' x 194 16'; h, pole on which horses work; d, frame of 2' x 31 posts for driver to
Fig. 2.--Plan of grader, showing mode of attachment to horses, with rolling fulcrum wheels f. The end of frame attached to
bolted to under side of pole. The dotted lines show position of grader
Fig. 3.—Plan of plate 6, £ inch thick.
WILKINSON'S IMPROVED RUT SCRAPER AND GRADING MACHINE.
break the lading, and destroy the road. The wheel of a loaded vehicle, alling from a stone over which it has rolled, even if it is not more than !wo inches in height, will injuro a road surface more than the natural rolling wear on a smooth surface in running a mile. The same may be Said of the effect of loose stones on a macadamized road, only that the damage to the latter is more serious than to the earth-road surfaces, which will in some degree repair themselves; but the displaced, inacadamizing material is strewed upon the surface of the road, greatly increas. ing the evil. Next in importance to drainage is the removal of loose stones from the surface of the road, and the best and cheapest mode in íhus clearing earth and gravel roads is to run the rut scraper or grader over the road, commencing at each margin with the scraper, so set that the surplus earth, stones, &c., will be continally deposited toward the center of the road. Having passed the scraper over the entire surface, by passing up one side and down the other, all the small stones to be removed will be deposited in a narrow row on the middle of the road. bed, from which they may be rapidly gathered by the use of the malleable cast-iron coal-scoop, which being latticed allows the earth and gravel to fall through. Loose stones may thus be removed from the surface of earth and gravel roads at perhaps one-tenth the cost of handpicking, and all ruts filled at the same time. The loose stones on mac. adlamized roads should be frequently picked off, and the side tracks kept in order by the use of the grader, as above described.
Great advantage and economy result from passing the rut scraper over earth and gravel roads as soon after every rain-fall as the soil becomes dry enough to flow before the scraper, and readily fall into the ruts and depressions in the road surface. Where water is allowed to stand until evaporated from the ruts, large and frequently dangerous mud-holes are the consequence; and as they are generally repaired by casting in stones, small and large, the road is made worse, instead of better. Mud-holes in roads are striking examples of a veritication of the adage that “prevention is better than cure;” and prevention can be effected in the most simple and economical manner, by the use of the rut scraper. If taken in time, it is rarely necessary to haul soil for repairs, that removed by the scraper from the margins of the ruts generally being all that is requisite to raise the depressions to the proper grade.
The objectionable course of conveying surface water across roads on the surface, instead of by the use of a proper culvert, is common in all parts of the country, even on macadamized roads charging heavy tolls. The damage annually done to teams in such cases is more than the cost of a culvert. These water crossings are often, in winter, a sheet of ice ten to twenty feet in length and as wide as the road, in crossing which teams are often seriously injured by slipping.
WATER FOR TEAUS.
It is a matter of so great importance that a full supply of water by the roadside be provided for teams, at intervals of at least an average of five miles, that the subject should no longer be neglected, but a provision for securing a supply should be made in the county road laws. Except in very flat dry countries, it is generally practicable at trifling cost to arrange water troughs at proper intervals, so that water will flow in and out perpetually. The supply-pipe should always be inserted into the bottom of the trongh, and not rise much above the surface of the water when the trough is full; for, if it does, the water is apt to be blown about and to freeze, so as to make the approach to the trough danger