These great water highways necessarily interpose a formidable obstacle to the spread of population in either direction, and although the introduction of steam ferriage and the construction of the Brooklyn bridge have modified the inconveniences of tran.sit across broad rivers, the general trend of population continues to the northward. Elevated railroads and the development of transportation facilities have brought all portions of the county within easy reach, and New York is steadily absorbing the outlying territory. Morrisania and Fordham have already been appropriated, and, with the accelerated ratio of increasing population, the day is probably not far distant when almost the entire county will have become little more than a suburb of New York.

A writer of twenty years ago,' speaking of the contemplated imjjrovements beyond the then northern boundaries of the city, says : " Assuredly this region will be the site of the future magnificence of this metropolis. During the coming five or ten years the Fifth Avenue will no doubt be soonest built up, and built up grandly, but the city will not stop on that account; it will be succeeded by an age of imperial magnificence. That will be the day for the now neglected west side of the island. The poetical prophecy,

' Westward the star of empire takes its way,'

and which is fast becoming historical truth, will receive another illustration." Much of this prediction has already been realized and a comparatively brief period in the future may be expected to work a wonderful transformation in the physiognomy of those portions of Westchester County which as yet have not assumed the distinctively urban character.