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in a similar manner until the proper depth is obtained, which varies between 6 inches and 9 inches, according to the class of road or street. The surface is finished with a transverse fall frons the centre to the sides of 1 inch in 4 feet. In towns and villages the side channels are paved with good pebble paving, and in country districts the side channels, or “water tables,” are formed in the surface, by the junction of the same with the edge or curb of the footpath, or side margins; and the surface water is discharged through small outlets 9 inches by 6 inches, built under the footpaths and fences, into the open back drains. In making roads across peat bogs, their nature and depth is first carefully ascertained. If the bog is sound, and resting on a clay or firm bottom, the road can be made without brushwood or timber. The side-drains are first cut for such a depth into the solid sound peat as will not lower the water more than about 18 inches or 2 feet below the surface of the intended road. Outside parallel drains are then cut, at distances and depths calculated according to the nature of the bog, and the depth to which it may eventually be cut out for fuel. The side drains are connected with the outside parallel drains by small cross drains. The whole is then allowed to stand for a few months, to drain and settle down. When so drained and consolidated, and the water has assumed its altered level in this part, the space to be occupied by the roadway is then cleared, by removing all the top and light portions of bog, down to the sound solid peat; on this is laid a layer of good tough grass sods with grass side down, and over these is laid clay, or good stiff soil, in thin layers carefully punned for a depth of from 6 inches to 9 inches; over this (if obtainable) is spread a layer of fine gravel or coarse sand, and then the broken metal is laid on, as described for upland roads. The Author does not use stone pitching or heavy stones for a solid foundation in making bog roads. If a floating or “shaking” bog has to be crossed, the side and parallel drains are made as described, but each as shallow as possible so as to avoid weakening the mass of floating peat crust. After the drains are cut on such bogs, the site usually sinks very much, and must stand until it attains somewhat of a permanent level. The top is then cleared over the site for the roadway, and a bed of gorse, heather, or very fine bushes, is carefully laid down on the wet peat, and layers of fascines or strong brushwood well crossed are laid over it, of size and depth according to the weight of the traffic to be carried. All the brushwood, &c., is filled in with moist peat, the whole being brought up in this way to the proper level, on which grass sods are laid, and the roadway is constructed as already described for firm bogs. It is essential that all the brushwood, &c., should be laid below the line of saturation at such a level as will ensure its being kept constantly wet, together with the peat packing; as peat being a powerful antiseptic, all, if kept in a wet state, is preserved from decay. When the Irish roads came under the control and supervision of trained and experienced civil engineers as County Surveyors, they were found to be in a very bad state, and the country was too poor to warrant the expenditure needed to remake them. Consequently all that these officers could do was to try and improve the roads as far as possible with the means at their disposal, and this has been no easy task under the existing conditions, which are briefly as follows:— (1) The grand jury are bound to put up all work to tender, and to accept the lowest tender, even if the amount named is obviously inadequate, provided the tenders be considered bond fide and the sureties sufficient. (2) The contracts are usually let to men who are ignorant of and unskilled in the performance of the work that they undertake. (3) The sums allowed by Presentment Sessions are often quite insufficient, while in other cases, if a “job" has to be perpetrated, . more money than is needed is allowed by the Sessions. These are some of the difficulties with which the County Surveyors have to contend, and they are only able to overcome them by the exercise of constant care and vigilance, and by fearless discharge of their duties. In 1836 there were 13,191 miles of roads under repair and maintenance by the grand juries in Ireland, the annual cost being £228,316, or an average cost of £1768, per mile. In 1895 there were 53,064 miles of roads under them, at an annual cost of £660,532, or an average cost of only £12 98. per mile. Had the average expense remained unchanged, the total expenditure would now be £918,007, or £257,475 in excess of the present outlay. This fact is all the more remarkable when it is remembered that the usual pay of a labourer in 1836 was but 6d. per day, while the present rate of pay averages from 18. 6d. to 2s. 6d. per day. Moreover, since 1836, all the main and post roads have been placed under the grand juries. These latter roads were previously maintained by the Board of Public Works and by the various turnpike trusts. In the face, therefore, of an increase of between three- and fourfold in the price of labour, and with the addition of
all the roads that are most expensive to maintain, there has actually been a saving to the country of no less than £257,475 per annum. The total cost of supervision by County Surveyors, together with their assistants and staffs, is at the rate of about 4} per cent. on the expenditure. The tax for the repair and maintenance of the public roads amounts to an average rate of about 18. in the £1 on the valuation. The highest prices paid for the repair and maintenance of county roads are found in the immediate vicinity of the cities of Dublin and Belfast, where steam-rollers are employed, and there the cost reaches £394 to £470 per mile; while in the wholly rural districts the prices fall to £2 per mile, and even, less. The principal materials available for repairing and maintaining roads over the greater part of Ireland, are the different kinds of limestone, which vary considerably in character and in hardness, from the light friable and indurated chalk to the hardest blue limestone. In some districts trap, basalt, granite, syenite, whinstone and clay-slate are, however, in use. In all parts of the country it is necessary to employ the nearest available materials, as means of transit are wanting to bring stone from a distance. Limestone, though good enough for roads of light traffic, is, as is well known, not well adapted for roads carrying heavy traffic. The system pursued by the Author in effecting the improvement of roads, has been, first, to pick out any large stones making their appearance at the surface, and to replace them with broken metal; second, to increase the thickness of the crust of the roads, and to bring them to a better formation; and third, to improve the drainage as far as possible. In the case of old roads which have never been properly constructed in the first instance, this course was the only suitable method, since many such roads were originally simply lanes, pass-ways, or private roads. These were subsequently presented for “repairs” merely by the grand jury, though they should really in many cases have been presented “to re-make,” as they have since become important thoroughfares. It is often surprising to find how much has been accomplished by the above-mentioned methods in bringing these imperfect roads into fairly good condition at a nominal cost, but such roads are not of course adapted for continuous heavy traffic. The Author has in his charge about 1,000 miles of public roads under maintenance and repair, and the only local stone available is blue or grey limestone, either in the rock or in drifts of gravel and boulders. In certain of the mountain districts it is possible to make use of the local clay-slate or sandstone grit, but these materials are of inferior quality, and they can only be employed for mountain-roads, where the traffic is very light.
A large number of Irish roads traverse great stretches of peatbogs or floating morasses, some of which are of considerable depth, and the Author has found that in the maintenance of these roads the management of the longitudinal side-drains is of the greatest possible importance. If the subsoil is drained too much, the peat, when it becomes dry, loses all its glutinous matter, rots away and crumbles under the crust of the road, and the road then becomes liable to drop into holes. He has found that the soundest bog-roads are those in which the level of the water in the longitudinal side-drains is kept at about 18 inches below the surface of the road. This can best be managed by forming small, shallow side-drains with cross drains to discharge the flood-water into larger parallel drains, cut into the bog at a considerable distance away from the road, and made deeper than the adjacent side-drains. Under such circumstances the peat beneath the road always retains sufficient moisture to keep it in a sound condition, and it does not part with its adhesive qualities; while in the case of roads crossing peat-bogs, which have been cut out for a considerable depth below the level of the road, and too close thereto, the roads are always in an unsound condition, and they appear to expand or contract according to the state of the weather. The crust.of the road is then broken up, and is caused to ravel in very dry weather, though it heals up again and remains firm when the weather is wet. The Author has further observed that roads over peat-bogs are not so much injured by frosts as are the upland roads.
The system of repair generally adopted in Ireland is that of “darning” or patching, and the Author's specifications (Appendix II) provide that the parts to be repaired are to be picked and loosened to a depth of , inch (rather more at the edges), the new materials are then to be spread over the same, and are to be blinded over and consolidated with a pounder. In very wet weather, and after frost, on roads of heavy traffic, the picking and pounding are omitted, as the stones bind at once; but if the roads are repaired during spring, summer or autumn, picking and pounding are required. On the roads in the Author's charge, the metal for light traffic districts is broken between 1 inch and 1% inch in size, and for roads of heavy traffic to about 2-inch gauge. Gravel is also extensively used for light traffic roads and for summer repairs, in those districts in which it is procurable.
Iti is advisable to apply the patches of new metal alternately at each side of the road, extending therefrom to a little beyond the centre, and at distances of from 25 yards to 30 yards apart. A clear footway is thus obtained for horses to travel on without treading on the fresh patches which the wheels roll in, and ease and comfort is experienced in driving when only one wheel crosses a patch at one time. If the roads are systematically repaired in this way, taking up alternate portions and not applying too much material at any one operation, they may be brought into very good condition without the aid of rolling. It is well to provide for a stipulated annual minimum supply of materials, calculated according to the requirements of each road, so far as the same can be ascertained. These supplies should be delivered by measurement on or before the 25th September in each year, and should be worked into the roads on or before the 1st April following, with the exception of a small stock of finer materials for summer repairs. Steam-rolling has not been adopted to any extent in Ireland, except in the outskirts of the large towns; and the powers under the Grand Jury Acts are insufficient to admit of the purchase or use of such rollers by County Surveyors. The footpaths along certain of the public roads are principally made with a surface of gravel or fine screenings from the road metal. In a few cases near towns, concrete, asphalt and tarpaving have been used for this purpose; but the employment of concrete in situ has not been recommended where gas- and waterpipes exist, owing to the difficulties of opening, closing, and repairing it. The repair and maintenance of ordinary footpaths are generally included with the cost of the adjoining roads, and the figures already quoted comprise the outlay upon the footpaths. The system of letting contracts for repairs to the local farmers, though it is attended with some advantages, is fraught with drawbacks. As the contractors, with the aid of their sons and friends, themselves execute the work, it is difficult to ensure regular and systematic attention to it; and the plan is open to considerable jobbery and to certain dishonest practices, which can only be kept in check by the utmost vigilance on the part of County Surveyors and their assistants. If honest local contractors could be secured who would undertake contracts for roads over a considerable extent of country, the system might answer well, but it is impossible, in most places, to find substantial men willing to accept such work. Moreover, skilled workmen are really needed for the repair and maintenance of roads, but they cannot be procured except by training, and most