PAVEMENT FOR ROADS. As the advantages of good roads through the country are unquestionable, so the bene fits of well paved streets in cities are no less apparent. Good roads are an evi dence of civilization. The Indian follows the trail of his forefather, and gives evi dence of some kindred instinct like the brute, but the civilized man levels the mountain and fills up the morass, to make a permanent pathway for the horse and his rider, the carriage and its driver. The importance of good roads was not un known to the ancients, and to the Car thagenians, a commercial people, is the invention of paved roads traced. From them the Romans learned the art as they did that of ship-building. During the reign of Julius Ciesar, the Capital was in communication with the chief towns by well paved roads which branched from the seven-hilled city, at one time, to every province of the empire. The Romans introduced their system of roads into Britain, and they were made upon a gigantic scale, with an eye to permanency, at being the common opinion then that the Roman Empire was to endure for ever.
The Perrine pavement lately laid down in New-York is a pavement made of ob long blocks of trap, each of about 10 inches long, and six broad, and six deep, neatly trimmed. The ground is excavated about 14 inches, and a strata of 4 inches gravel mixed with sand and some plaster of Paris is laid down and well beetled and levelled and then sprinkled with water. Then another strata is laid down of the same stuff and treated in the seine way, making it slightly convex. On the top ;of this these oblong blocks are laid in among a bed of sand mixed with ground burnt brick. These blocks must be ac curately laid and well rammed down, and in our opinion will make the best pave ment for a business city like New-York, where there is an immense amount of travel.
The idea of paving the streets of mod ern cities is derived from, and based upon the Roman roads. Many of these are still in perfect repair in Italy, especially in the neighborhood of Rome. The stones are generally of trap rock, of a polyangu lar shape, of a very large surface, and about fourteen inches deep. They are slightly pyramidal, and set with their broad faces upwards. They are well fit ted together, and sometimes laid in ce ment, though not always. In Naples, the blocks are rectangular (mostly square) of about two feet, by two surface, and six inches in thickness, well fitted to gether, placed diagonally on the street, and laid in a thick bed of Roman cement. This pavement excels in solidity and even ness, but becomes dangerously smooth, hence it is necessary, from time to time to cut grooves on its surface. The city of Rome is paved with blocks which are parallelograms, of about ten inches square surface. They are laid in a thick bed of
cement. In the cities of Northern Italy, the roads may be called stone railroads, as the tracks for the wheels are broad flat stones, laid with precision, while the tracks for the horses' feet, between the lines, are paved with small stones. This is a good pavement, when well made, and was partially carried out on the great turnpike between the cities of Albany and Schenectady, in New-York. None of these kinds of pavements are suitable for such a city as New-York.
A great number of different kinds of pavements have been tried in New-York city. The cobble stone or small boulder pavement, is the oldest, and not a bad pavement when well laid down, but this is seldom the case, and one great difficulty in the way of its endurance, is the great variety in the quality of the stones. Wooden blocks were at one time suppos ed to be the best of all pavements, before their enduring qualities were tried. The pavement which has got the name of " Russ" in this city, is nothing more nor less than the Neapolitan pavement, only its pozzoloni bed of concrete, for the diagonal blocks, is made in sections. It will soon have to be treated in this city, after it becomes smooth, like the pave ment in Naples. This is the only objec tion to it, but'ts a very serious one.
Pavement with rough tops is best for steep inclines, to allow horses to pull heavy loads up the same, and although not re quired in such a city as New-York, it may be good for some other city. The Perrine pavement is not suitable for streets like Broadway, where the carriages and canni busses will be continually crossing the tracks, and it will be expensive for re pairs, because there is so much street lift ing for gas pipes and common sewers. The Rum and Perrine pavements are solid and lasting, but we must look to a pavement that will be enduring, easily repaired, easily laid down, and that will obviate the surface difficulties of the two pavements mentioned.
A new system has been tried in Lon don, and has been tested for ten years with the most gratifying results. This method is to remove the subsoil to the depth of sixteen inches, then lay a layer of 4 inches of strong gravel, well rammed down, then another layer of gravel, and a little chalk is well rammed, and a third of the same stuff, all well rammed, and the street made slightly rounding. Stones of good granite four inches deep, three inches thick, and four inches long, are then laid down in fine sand, each care fully placed not to rock in its bed, and the whole surface well rammed down. This system has been found, by thorough experience, to be infinitely preferable to the large blocks, and for that reason it is well worthy of the attention of our city authorities.