The granite-eube roads are preferable to macadamized in point ofdurability, and therefore are more eligible in this respect fur places where there is great traffic, but neverthe less there are objections which partly outweigh these ad van tages, 'one of which, of considerable importance, arises from the circumstance of the wear and tear of vehicles being very great on such roads on account of the frequency and violence of the concussions to which th•ly are subject ; and although the draught upon macadamized roads is, generally speaking, heavier than upon pavement, yet this ad vantagels probably more than neutralized by the concussions alluded to, which form a great impediment and injury to vehicles travelling I wiekly Another objection is, that a horse has not nearly so secure a footing upon paving as upon a broken•granite road.
A system of tram-roads has been adopted flw special traffic on some roads with great advantage, as in the Commercial and East India Dock roads, where two parallel lines or tramways of masonry are laid for the wheels to run upon, the space between being paved with the ordinary paving. These trains were made of large blocks of granite 5 or 6 feet in length, 16 inches wide, and 1• inches deep, and have been found to stand the heavy traffic much better than ordinary pavement would have done.
Roads paved with blocks of wood are of comparatively recent invention, and offer many advantages over common roads, in the evenness of the surfhce, but more especially by the prevention of noise, which is a great inconvenience on paved roads. It is to be regretted, however, that with such advantages it has defects, which, until removed, will put an effectual bar to its general employment ; we allude to its want of durability, and consequent expense, but more espe cially to its slipperiness in wet and damp weather. The for mer objection we feel confident may be removed by employing greater care in the construction and drainage of the substruc ture ; and the latter has been remedied, in some degree, by spreading broken granite on the surface.
In concluding this article, we beg to recapitulate the prin cipal points to be attended to in the construction and manage ment of roads :—viz.; a good solid foundation,properdrainaga, and efficient cleansing. We subjoin a table of the compara tive costs of various kinds of Roads with some cursory obser vations on their peculiarities.
ROD, a linear measure of 161 feet. Also a superficial measure of :274 square feet, by which brickwork is usually calculated ; the rod contains 272-1 square feet of brickwork, a brick and halt' thick, or 30G cubic feet.