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Page 83 - It is a known fact, that a road lasts much longer over a morass than when made over rock. The evidence produced before the Committee of the House of Commons, shewed the comparison on the road between Bristol and...
Page 82 - ... be made quite dry, and a covering impenetrable to rain, must then be placed over it, to preserve it in that dry state ; that the thickness of a road should only be regulated by the quantity of material necessary to form such impervious covering, and never by any reference to its own power of carrying weight.
Page 83 - The thickness of such road is immaterial, as to its strength for carrying weight ; this object is already obtained by providing a dry surface, over which the road is to be placed as a covering, or roof, to preserve it in that state : experience having shewn, that if water passes through a road, and fill the native soil, the road, whatever may be its thickness, loses its support, and goes to pieces!.
Page 191 - But the great advantage of a rail-way will consist in its affording the means of transporting heavy goods with speed and certainty : if it be only so far as to double the speed of the fly-boats, it must be a material benefit. And recollecting that rail-roads are yet in an imperfect state, while the united talents of our civil engineers have been chiefly devoted to canals for about a century, we may confidently hope that there is yet scope for improvement ; and we may fairly infer that for new works...
Page 83 - Having secured the soil from under water, the road-maker is next to secure it from rain water, by a solid road, made of clean, dry stone, or flint, so selected, prepared, and laid, as to be perfectly impervious to water : and this cannot be effected, unless the greatest care be taken, that no earth, clay, chalk or other matter that will hold or conduct water, be mixed with the broken stone, which must be so prepared and laid as to unite by its own angles into a firm, compact, impenetrable body.
Page 82 - ... that it is the native soil which really supports the weight of traffic ; that while it is preserved in a dry state it will carry any weight without sinking, and that it does, in fact, carry the road and...
Page 193 - ... the two plates. The plates are joined by a dovetailed notch and tenon, and an oblique plug is cast on each plate, which is let into the stone sleeper. But, for the advantage of taking up the plates, to repair any defect, there are plates at every thirty yards, with perpendicular plugs ; such plates are called stop plates.
Page 82 - The roads can never be rendered perfectly secure, until the following principles be fully understood, admitted and acted upon : namely, that it is the native soil which really supports the weight of the traffic ; that while it is preserved in a dry state, it will carry any weight without sinking...