WASHINGTON SQUARE is located between Fourth and Seventh streets, at the lower end of Fifth avenue. The site was originally a Potter's Field, and it is said that over one hundred thousand persons were buried here in days gone by. The square contains a little over nine acres, and is handsomely laid out, and adorned with a fountain, around which passes the main carriage drive, flowers, shrubbery, etc. The trees are among the finest in the city, and are kept with great care. An iron railing formerly surrounded the grounds, but in 1870-71 this was removed, and Fifth avenue was extended through the square to Laurens street. This street was widened and called South Fifth avenue, thus practically extending the avenue to West Broadway at Canal street. The square is surrounded by handsome residences. On the east side are the University of New York and a Lutheran Church. TOMPKINS SQUARE is one of the largest in the city, and is laid off without ornament, being designed for a drill ground for the police and military. It occupies the area formed by avenues A and B, and Seventh and Tenth streets. UNION SQUARE, lying between Broadway and Fourth avenue, and Fourteenth and Seventeenth streets, was originally a portion of the estate of Elias Brevoort. In 1762 he sold twenty acres lying west of the "Bowery Road" to John Smith, whose executors sold it to Henry Spingler for the sum of 950 pounds, or about $4750. The original farm-house is believed to have stood within the limits of the present Union Square. About the year 1807 Broadway was laid off to the vicinity of Twenty-second street, and in 1815 Union Square was made a "public place," and in 1832 it was laid off as it now exists. The square is regular in shape, and the central portion is laid off as a park, and ornamented with shrubbery, flowers, walks, and a fountain. It is one of the prettiest parks in the city, and covers an area of several acres. It is oval in form, and is without an enclosure. [Picture: THE WASHINGTON STATUE IN UNION SQUARE.]