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system of surface gutters above recommended, is very large, and the annual waste of fertility and the damage from loss of fences, bridges, buildings, and even of human life, are so great as to warrant a notice in this connection, apart from its direct pertinency to the general subject in hand. We have been frequently called to relocate roads that have been entirely destroyed by floods in collateral streams, many of which roads had been repeatedly destroyed in places, and as often rebuilt. Au ordinary degree of sagacity and common sense should have suggested the folly of locating such roads originally so low as to be subject to such casualties, and certainly the repeated ocular evidence of the error committed by the pioneer road surveyor (for such he must be called, as there was no engineering in the case) should have deterred the commissioner of highways from reconstructing such roads on the same sites. Many cases of injudicious road construction and waste of public money could be cited, were it necessary, to establish the fact that reform and retrenchment, greater skill and wiser legislation, are needed for the more economical and efficient management of the public roads throughout the country.

As the existing road laws in all the States are generally "unsatisfac tory," a recital of many of them in this article is unnecessary. Oscar I. Strong, of Pocahontas County, Iowa, reports the following road laws in that State: "The board of supervisors has the general supervision of roads in the county, with power to establish or change them as provided by law. The town trustees levy a road tax each year of not less than one mill nor more than three on the dollar of the taxable property in each road district. A road supervisor is elected in each district, who has the supervision of the roads in his district, and it is his duty to keep these roads in as good repair as he can with the funds at his disposal; it is also his duty to require each able-bodied man between twenty-one and fifty years of age to perform two days' labor on the roads, between April and August of cach year. The operation of the law does not give satisfaction. The average amount of work done on our roads does not exceed six dollars per mile per annum. The best road in the county is made of saw-dust."

E. M. Mackemery, of Leavenworth County, Kansas, reports as follows: "All the principal roads in the county are under the supervision and care of a scientific engineer, who is the adviser of the board of county commissioners. The roads are graded, and worked on an established system, and all thoroughly and substantially bridged with blue limestone of superior quality. In no State in the Union is there a greater pride, or a more intelligent appreciation of the value, comfort, and pecuniary profit arising from a well-devised system in, and a thorough improve inent of, all classes of roads. An experience of twenty-nine years in Illinois, Iowa, and Missouri has established the conviction that more gratuitous labor is performed on the roads of Kansas than in any other western State. At a cost of a little less than $250,000 the county has bridged every stream on the principal roads leading from Leavenworth City. The city of Leavenworth has also, at a large expenditure, built all stone bridges, even beyond the city limits, to facilitate trade with the interior. After roads are opened, the annual amount expended per mile does not exceed $250.

Arthur Parks, of San Bernardino County, California, states that "every male citizen in the county, Indians excepted, is taxed one day's work or two dollars per annum, besides which there is a small direct tax. The law is generally enforced, but is not satisfactory, as it is not suflicient to keep one-fourth of the roads in order. Private subscriptions of

one hundred dollars each are not rare for mending our ways.' The citizens of this county fully indorse the leading paragraph of your cir cular; and, realizing its correctness, we are determined to take hold with a will, and have good highways."

There is great similarity in the systems of taxation for road purposes, it being generally a "poll tax" in labor, varying in the different States from one day to five per annum; and in some portions of the country a money tax, varying from one mill to two cents on the one hundred dollars; and in others a tax for bridge purposes alone, as high as four cents on the one hundred dollars of taxable property. Owing to the abundance and excellence of material in some regions, and the scarcity and inferiority of it in others, there is a difference of at least tenfold in the cost of construction and maintenance of good roads. Good ones are the exceptions in all the States. Those of eastern New York and of New England have generally a surface superior to those of almost any other portion of the country, but the grades are rarely reduced to what they should be. To the steepness of the grades in the line of the axis of the roads in those regions, and to the care in surface drainage, their dryness and smoothness of surface are mainly attributable, as it causes them to shed water rapidly.

The proper mode of construction of a road adapted to a large amount of heavy traffic, at all seasons of the year, depends greatly on local circumstances. The perfection and the durability of a road must, of course, depend on the material used in its construction, all other circumstances being equal. We shall treat the subject in the order in which the earthy and the mineral materials, in the various parts of the country, possess their respective superiority for use in the construction of county roads: First, the macadamized or broken stone road; second, the gravel, or proper admixture of natural pebbles of various sizes with a proper quantity of clay and sand, or loam; third, rotten rock, of various character; fourth, rotten rock, artificially mixed with clay; fifth, loam, in a natural state; sixth, artificial loam, made by mixing clay and sand; seventh, clay; eighth, sand.

THE MACADAMIZED OR BROKEN STONE ROAD.

For the sake of brevity in treating class No. 1, we shall designate the rock to be used by the terms hard and soft. The mode of preparing the foundation of a Macadam road should be modified according to the character of the soil of which it is to be made. It may, however, be premised that one essential condition to be secured in the use of every character of material is that of dryness. This secured, almost every variety of soil will form a suitable substructure for a macadamized road. It would be difficult to furnish specifications for the great variety of cases that may be presented, but we shall endeavor to give such general instructions as will meet all probable cases intelligibly, and will commence with the most difficult circumstances likely to be presented, viz., an extensive plain, level, or nearly so, with a tenacious clay soil.

To effect drainage under such circumstances there are but two modes known to the writer: First, by surface drainage, by the use of open ditches, or gutters, excavated on both sides of the road in the manner described. If practicable, the fall should be made both ways, from a point as nearly central as may be, and each gutter be extended to a point of discharge lower than the plane. The advantage of draining both ways is, that with ditches of the same depth at their discharge end, the fall will be doubled. In case the distance is great, and the labor of

producing sufficient fall in the ditches is considered too expensive, it will then be judicious to test the practicability of the other method. This consists in what we call pit-drainage. Its practicability can always be ascertained by digging a well, or by boring with a pile or post auger. If a stratum of sand or gravel, which will absorb water, is reached at a reasonable depth, say not more than forty feet, this plan may be adopted. Three or four wells, equally distributed as to distance will be ample to drain a mile of road. If the wells are to be stoned with rough stones, they should be excavated six feet in diameter, and the depth continued three feet below the surface of the stratum which is found to absorb water. The rough stone wall may be laid dry, but the stones should extend from the inner face to the bank, the smaller ends forming the inner face, thus forming a complete arch of every layer of stones. The wells may all be on one side of the road, or a portion of them on each side, and they should be covered with a strong lattice of cast iron, with meshes about two inches square.

The gutters should fall each way toward the wells, and the low places in the gutters on the other side of the road should be opposite the wells. At each of these low points a well a foot or two in depth should be excavated and stoned up. A tile or a stone drain with good fall should connect the shallow with the deep well. The greater the fall in these cross drains, the smaller may the conduit be, and the less the liability to clog. A slight circular depression should be made in the bottom of the surface gutters around the wells, in which the sediment in the drainage water may be deposited before it flows into the wells. It sometimes occurs that the water, not being carried off rapidly enough, will rise up to, and even above, the top of the well; but this is rare, and the foregoing mode will generally provide satisfactory drainage under the circumstances described. When practicable, the surface gutters conveying the water to streams or to ravines may be of more simple and of preferable construction. Where the water is to be conveyed a long distance, say half a mile in one direction, a fall of three inches to one hundred feet will answer. This will require the gutter to be six feet eight inches in depth at the discharge end. The bottom of the gutters must be smooth and graded with accuracy. The angle of the slope of the banks should not exceed thirty-five degrees.

In tenacious clay soils the margin of the surface of the substructure, on which to place a Macadam road-bed, should be at least one foot above the bottom of the gutters. It should be made smooth and solid, and have an underdrain at each margin of the macadamizing from six to twelve inches in depth, and an average of twelve inches in width. These drains may have a fall each way for five to seven rods, to a low point from which a lateral drain should extend under the side road to the gutter into which they are to discharge. The longitudinal underdrains are to be made of broken stones, and are to be filled up to the level of the surface upon which the macadamizing is to rest. The earthbanks on each side of the macadamized portion of the road should be twelve inches in height, and be sufficiently sloped to be self-sustaining until the broken stone has been applied, which will render them perfectly secure. The stone should be so broken that all, or nearly all, the pieces will pass through a two-inch ring. This is the rule adopted in England, where this kind of road has reached the greatest perfection. We say "nearly all," for of course there will occasionally be stones which, unless too much time is spent in breaking them, will not come up to the standard. This subject is one of the utmost importance; and, if we are to be governed by the opinion of Macadam himself, we find

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him declaring that cubes of one and a quarter inch are better than any larger; and he affirmed before a committee of the House of Commons, that his experience went to prove that the expense of keeping roads in repair was almost in the exact ratio of the sizes of stone used in each instance. Thus, a road constructed of metal broken down to cubes of one and a quarter inch would require to keep in repair but one-half the outlay necessary for one constructed of cubes of two and a half inches; so that the increased cost of construction in using the smaller broken metal will be fully compensated for by the saving in repairs and greater durability. In speaking of the metal as being in the form of cubes, it is not intended to convey the idea that each piece of stone must be a perfect cube, and all of equal size; practical men will of course understand that the term is figurative, and that the metal must of necessity be more or less irregular, and vary in size considerably. The broken stone for a new road should be applied to the depth of twelve inches and twenty feet in width to produce a first-class road. The lateral slope either way from the center of the road should correspond with that of the surface of the foundation; this slope should be about onequarter of one inch to a foot. There should be an earth side track on either side of the macadamized portion of the road. The earth road, when dry and in good order, is more desirable than the Macadam, and materially saves the wear upon it. The foregoing specification, although referring more particularly to a road nearly level longitudinally, is equally applicable as a direction for macadamizing any road of the width mentioned.

The preparation and application of broken stone in road-making have hitherto been very expensive, thus presenting great discouragement to those desiring to improve roads upon this system, which we have no hesitation in pronouncing the best all things considered, as yet discovered. The cost, however, has of late been greatly reduced by the introduction of the "Blake Stone-Breaker," a machine of immense strength and efficiency, which has been satisfactorily tested in practical use. Thirty perches (twenty-five cubic feet to a perch) of the hardest trap boulders can be broken into the best road metal in ten hours by this machine. It requires about nine horse power to perform this amount of work in the time given. In a single hour it has been known to break four perches, or one hundred cubic feet, of stone of the foregoing character. With this machine the cost of breaking is reduced to thirty cents per perch, using coal at $5 50 per ton, and labor at $1 50 per diem, and an engineer at $2 50 per diem, who assists the two laborers employed in feeding the machine. The average day's work for a good hand in the spring, summer, or autumn is less than one perch, and in winter still less. The average price of such labor is about $1 50 per day at present, so that the reduction of expense by the use of the machine is not less than eighty per cent.

The stone-breaker referred to has elevators connected with it, which carry the stones to a considerable height above the machine, where they are deposited upon a sieve, through which the fine sand produced in breaking the stone passes, and is deposited by means of a chute in a tight compartment on the ground; while the stones running over the sieve are deposited in a kind of hopper, from which they are loaded upon wagons or carts by simply opening a slide or trap. In this manner the cost of loading is reduced to a nominal figure, being done almost instantaneously; while, if done by hand by shoveling from the heap, the cost of loading would be nearly half as much as breaking.

After what has been said with regard to the sand being carried down

through a chute into a tight compartment, we will explain why the trouble is taken to separate the sand from the broken stones at all, or care taken to deposit it in a tight compartment. It was found that this sand, produced by the trituration of stones of this quality in the process of breaking, is the very best material yet discovered for manufacturing "concrete stone" under the Ransom patent of England, which is rapidly coming into use in this country. About one hundred pounds of sand are made for each perch of stones broken, and all yet made by the machine in question has found ready sale to the "Ransom Concrete Stone Company of Maryland," at one cent per pound. It will be seen that in the neighborhood of cities, where the concrete stone is being manufactured to any considerable extent, a road may be macadamized at a very low cost, if indeed it is not found that the stones can be broken and applied at a cost which shall be less than the proceeds of the sale of sand produced from the amount of broken stone required, thus preparing the road metal free of cost, and leaving a profit to the constructors besides.

In the application of the broken stones to form a road-bed, although the process is simple, it is important that the surface of the earth substructure be kept free from ruts and tracks, as any depressions will fill with water, and soften the foundation at these points, thus causing the road to settle unevenly. Depressions in the stoned surface cannot be well repaired without "picking up" the metal to the depth of several inches. The material used in repair should be somewhat smaller or finer than that of which the road is formed. The portion repaired is to be thoroughly rammed with a "paver's rammer," and, when finished, should be slightly above the surface around it, which remains undisturbed. When the metal has been properly graded on a new road, the surface should have a slight dressing of clay, and a heavy roller should be passed over it until the metal comes to its bearing, before vehicles are allowed to pass over it. A road-bed twenty feet in width and twelve inches in thickness will require 4,224 perches of broken stone to the mile. The surface grade of the earth side tracks should correspond with, and be a continuation of, the grade of the macadamized portion. The side tracks should not be more than nine feet in width, as unnecessary width increases the difficulty of surface drainage.

Many professional road makers will take exception to the clay surface dressing, but it has been thoroughly tested in practice, and always with success. The effect is to bring the metal to a bearing at once, and to prevent the action of the wheels from destroying the angularity of the surface metal, a very important quality, as it is almost impossible, after the surface stones have become rounded, to get them to bind one with another, and form a first-class road surface. The quantity of clay applied should be sufficient only to fill the interstices between the stones. on the immediate surface, when the metal has come to its bearing. Another advantage of such an application is to render the superstruc ture of macadamizing water-proof, almost from the first, the importance of which, in assisting to maintain a dry foundation, is almost sell evident.

THE GRAVEL AND OTHER ROAD-BEDS.

Where the natural soil of a road consists of gravel of proper texture. in its natural state, the process of producing a very desirable road, for all except very heavy traffic, is simple and inexpensive. It only requires to have the surface of the road-bed raised by repeated plowings, the

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