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“ The old stone might last twenty years longer; but, at all events, would be worth 8s. per yard after ten years wear. That statement was made on a calculation of using the very best material ; but most of the pavement is laid down at from 7s. to 10s. per yard.
“ A macadamised, or broken stone road, requires for keeping in repair the first year, and every year after, two coats of three inches thick, to allow for wear: the coating costs ls. 9d. each yard : the cleansing and scraping cost 10d. each yard, as under:
£ $. d. First cost, per superficial yard - - 0 7 6 Two coatings, at 1s. 9d. each per yard,
for ten years - - - - 1 15 0 Cleansing, at 10d. per yard, for ten years - - - - - 0 8 44
Per yard - 2 10 10
“ The surveyor to the Commissioners of Westminster Bridge stated that the expense of paving
and keeping in repair the bridge for twenty-two years (from 1802 to 1824) was 3,494l., including 1,165l. for new pavement in the first year, making an annual expense of 1591. About two years ago the bridge was macadamised, and the year after cost 1,5071. 12s. 6d. There was a covering ordered in June 1825, which cost 172. 10s., besides Mr. M‘Adam's annual charge of 3001. The surveyor said he thought it now required another covering like that of last year, at the expense of 4701. 10s., as he had examined the road, and found the broken stones, on an average, not more than three inches thick.”
The following is also taken from a London paper, and shows what was the result of converting the pavement over Blackfriars' Bridge into a broken stone roadway :
Blackfriars' Bridge. “ The report presented to the Court of Common Council last week, from the General Purpose Committee, relative to Blackfriars' Bridge, stated, that the City Surveyor having declared Mr. M‘Adam had completed his contract for macadamising the same, the Committee had subsequently employed him to keep the bridge in repair, and that he had since delivered in a bill to them for no less than 4731. odd, for such repairs, during a period of only eighteen weeks. The Committee further stated, . that they had advertised for tenders to keep the said bridge in repair for twelve months, and several
offers had been made them; one offering to do the same at between 300l. and 4001., while a second tender was so high as 900l. In fact, it appears that the traffic over this bridge, which has greatly increased since it has been macadamised, is now to that amazing extent, that the new granite is ground to powder almost as quickly as it is laid down. It being thus evident that, to keep it in a proper state, the bridge would cost 1,0001. per annum, and the City having no separate funds for that purpose, the Committee recommended that it should be repaved on its present surface, on an estimated cost of 1,500l.; the expense of keeping which in repair used to average under 120l. per annum. The report further stated that Mr. M‘Adam offered, at the time of the alteration being effected, to keep the bridge in repair for 130l. per annum.”
In streets where the traffic is very great, a great saving of expense might be effected by paving about fifteen or twenty feet on each side, and having only about twenty or twenty-four feet of broken stone road in the middle. The drivers of heavily-laden waggons and carts would walk with more security on the sides than in the middle; and they could, therefore, drive their waggons and carts on the pavement, while the middle would be left free for lighter carriages.
In all hot climates roads should be paved, because neither small broken stones nor gravel will become bound together in a solid mass without moisture.
ROADS PARTLY PAVED AND PARTLY MADE WITH
To make a road of this kind, sixteen feet of the middle should be perfectly well paved, according to the rules already laid down, and the remainder of it on each side of the pavement should be made with small broken stones. The advantages that would be derived from such a road would be1st, to save the labour of horses, as before explained in treating of pavements; and, 2dly, to diminish the expense of repairs.
If a road of this description be constructed with good materials, and in a workmanlike manner, it will require but a moderate expense to maintain it in excellent order; but constant attention will be necessary to keep the part where the pavement and the broken stones join from being cut into ruts.
Whenever the traffic of a road is so great as to wear down three inches of hard broken stones in a year, the middle part of it should be paved. At this rate of wear half a cubic yard of materials will be requisite for every lineal yard of eighteen feet of the breadth of the road. This will make the expense of new stones alone, for a road thirty-six feet wide, per mile per annum, (supposing the cubic yard of broken stones to cost twelve shillings,) amount to 1,0561.
As it has been already shown that while the tractive force on a good pavement is 33 lbs., that upon a gravel road is 147 lbs., or, in other words,
that the labour of horses in drawing over gravel roads is more than four times as great as it is in drawing over pavements, it ought to be an invariable rule, in those districts where no other materials can be procured except gravel, to use pavements for those roads on which there is a large traffic. Thus, for instance, all the principal roads from London to the stone districts ought to be paved. If the pavements were perfectly well made, and all the hills reduced to inclinations of 1 in 40, a single horse would be able, without difficulty, to draw two tons weight upon them, and the present charges for the carriage of goods and merchandise might be reduced one half.
The following remarks of Mr. Telford on roads paved in the middle are taken from his first annual report on the Holyhead Road, dated 6th May 1824, p. 7:—
“ As there is an ascent the whole way from London to the Archway road, it is particularly desirable to have the road surface as hard as possible. Flints are much too weak. What has been done for improving the Kensington road suggests a proper remedy, and the complete success of this experiment fully justifies the same plan being adopted on this trust.* I am fully aware of the
* At the time when this was written a considerable portion of the old pavement remained. It had been laid down upwards of thirty years, had cost very little in repairs; and the complete success of the experiment, on a road formerly so bad, and on one of such great traffic, was fully acknowledged by all scientific road-makers. But as soon as the Metropolis Road Commissioners