A scientific English gentleman, now in this country, for the purpose of examining mines for an English company, has sent us, at our request, the substance of a conversation at table on the subject of wood pavements — a matter to which he had given attention in England. His surprise at the uncomfortableness of our streets, in comparison with every thing else in the country, was very strongly expressed, and we think we must allow that this one foot of the centipede march of civilization, has fallen culpably behind.
One would naturally suppose that the immense advantage which London has derived from adopting wood pavement, had been previously felt in this country, where the invention was first introduced from Russia; but it seems that the system has been badly applied both in Boston and new York; for surely there is no reason in the difference of climate, soil, or timber, to render the result so different from what it has been in London, where the experiments are considered as entirely successful.
Wooden pavement has not been tried for four years in England. It is laid in all the great thoroughfares, such as Regent street, Whitehall, Oxford street, Holborn, Strand, Cheapside, the New Road, and a large proportion of the city and West End. It is calculated that it will be universal over London in four or five years more. Since the difference in the results obtained, in the old country and in this, must be attributed to the different method employed, it will not be without interest to describe the English system.
The first experiment, on a large scale, was tried four or five years ago in the broad thoroughfare of Whitehall, on a principle patented by the Count D’Lisle. This system consisted in laying the timber blocks with the grain of the wood inclined at an angle. Each block of wood was diamond shaped, and, when placed, they partly rested on their base and partly on one another.
The angle adopted by Cound D’Lisle was that of the Diagonal section of the cube, but experience has shown that the precise angle is not of importance, and any angle from 55° to 70° will do.
When this pavement was laid first, one row of blocks, about five inches square and seven inches deep was laid across the street inclining from right to left; the second row was then laid inclining from left to right and each block of this second row was fastened by wooden joints to two blocks of the first row. The third row is inclined in the same direction as the first, and fastened to the second, — so that it si perfectly impossible for one block to alter its relative position. The whole mass becomes, as it were, one integral floor of wood; but it is an essential feature to the success of this mode of pavement that, although so solid, the particular mode of arranging the inclined blocks will allow them to expand by damp or contract by drought without any strain and without loosening the blocks. By Count D’Lisle’s plan, if they expand by wet, each block becomes imperceptibly more vertical; if they contract, each block leans a little more on its neighbor, but without any effort to disjoint the whole.
When this sort of pavement was first used, it was, like stone pavement, laid on gravel; but it was ultimately found that the water would get between the gravel and the wood, and the bed would turn to mud. Though the pavement did not break, it floated and waved under heavy weights. To remedy this defect, it was found necessary to form a basement of concrete, which was laid all over the street to the thickness of about 9 to 12 inches, and since this improvement has been introduced the success has been perfect. At the end of four years, in some of the greatest thoroughfares, not one half of the blocks of wood have been replaced, and the original cost in London is, we believe, 13d. Per square yard — thus joining economy to comfort.
The cost of keeping this pavement in repair is about 10 per cent, upon the capital.