Page:Encyclopædia Britannica, Ninth Edition, v. 17.djvu/496

458 calated beds of coarse-grained dolomitic marble and thinner layers of serpentine. These rocks have been usually sup posed to be Lower Silurian, but Professor Newberry holds that they have so great a similarity to some portions of the Laurentian range in Canada that it is difficult to resist the conviction that they are of the same period. The deep troughs through which the Hudson and East Rivers now find their way through New York harbour to the ocean are supposed by the same geologist to have been excavated in the late Tertiary period, in which Manhattan Island and the other islands in New York Bay stood much higher than they do now, when Long Island did not exist, and a great sandy plain extended beyond the Jersey coast some 80 miles seaward. Manhattan Island, for half its length from the southern point, slopes on each side from a central ridge. On the upper half of the island the ground rises precipitously from the Hudson River in a narrow line of hill, which again, on the eastern side, sinks rapidly into a plain bordering on the Harlem and East Rivers, and known as Harlem Flats. The surface is throughout rocky, with the exception of this plain, and levelling on a great scale has been necessary in laying out streets. The district beyond the Harlem river, which extends as far north as the city of Yonkers, is traversed by lines of rocky hill running north and south, and still thickly wooded. The original settlement out of which New York has grown was made on the southernmost point of the island, and it has, since the beginning of the 18th century, spread due north and from river to river.

The street called Broadway runs for nearly 3 miles along the crest of the island, forming for that distance the central thoroughfare from which streets spread with some regularity to the water on each side. The lead ing thoroughfares originally followed the line of the shore, along which the ear liest buildings were chiefly erected, the central ridge being the last to be occu pied, until the city reached what is now known as Wall Street, the site of which was marked by a rampart and stockade extend ing from river to river across the island. Within this space the streets were laid out either as convenience dictated or as old pathways suggested, without any general design or any atten- tion to symmetry, and were named, for the most part, after prominent settlers. The first regular official survey of the city, tracing the line of the streets, was made in 1656, when Wall Street was its northern limit. In 1807 the present plan of the city was adopted, with its broad longitudinal avenues crossed by side streets at right angles, beginning at a point about two miles from the Battery and running the whole length of the island. The erection of buildings along these streets has led to the levelling of the region below the Central Park, but in the park the varied outline which once characterized the whole island is still retained. The precipitous banks of the Hudson river at the upper end have also compelled a treatment in which the original configuration of the ground is pre served, and the streets and roadways are adapted to it. The city in its growth northward absorbed several suburban villages known as Greenwich, Harlem, Manhattanville, Fort Washington, Morrisania, and Kingsbridge.

General Aspect. The appearance of New York everywhere but in the leading thoroughfares is usually disappointing to strangers. The pavement of all the streets, except Broadway and Fifth Avenue, is bad, and the street cleaning in all but the principal streets is very defective. The lower part of the city, which is the centre of trade, is generally well kept, and contains a large number of imposing buildings. Wall Street in particular, which is now, after Lombard Street, the most important haunt of moneyed men in the world, has several banks of effective architecture, together with the United States custom house; while Broad Street, which runs off from it at right angles, besides having the stock exchange, is being rapidly occupied at its upper end by handsome buildings of vast proportions intended for the offices of merchants and bankers. After the city had spread beyond Wall Street, the well-to-do portion of the population and the leading retailers seem to have clung to Broadway as the great lino of traffic and trade. For one hundred years the wealthy residents built their houses along it, or, if in the streets running off from it at right angles, as near it as possible ; and the shops followed them up closely. As population grew during this period the private dwellings of the better class simply moved up farther on Broadway and the adjacent streets, leaving the old houses to be converted into shops. The farther from Broadway, and the nearer the river on either side, the cheaper land was, and the poorer the class of houses which sprang up on it. This fondness for Broadway in a great degree explains the aspect of the city. About a mile and a half from the Battery, or southernmost point of the island, the cross 