The natural southern boundary of the table-land occupied by the parade ground is a rapid slope that occurs about in the line of Sixty-Sixth street; in this slope it is proposed to sink one of the transverse roads; and on a level plane below it, stretching to the south, a playground about ten acres in extent is located, as indicated on the plan. We have thought it very desirable to have a cricket ground of this size near the southern boundary of the park, and not far from the Sixth and Eighth avenue railroads, which offer the most rapid means of access from the lower part of the city.[8] [8] The playground has been arranged as here recommended. In this playground sites are suggested for two buildings of moderate dimensions: one for visitors to view the games, which would be appropriately located on a large rock that overlooks the ground; and the other for the players, at the entrance from the transverse road, by which an exit could be obtained from the playground after the other gates were closed.[9] Only one mass of rock of any considerable magnitude would require to be blasted out for the purpose of adapting this ground to its intended purpose; its position is indicated on the plan by a red cross, and the object of its removal will be seen on examination. This part of the design is illustrated in study No. 2. The ground at the south-west corner of the park it is proposed to fill in sufficiently to make, on the plan indicated, an agreeable Eighth avenue entrance. [9] NOTE, 1868.—The foundation for this building was laid during the last season. * * * * * [Sidenote: The lower lake.] To the south-east of the promenade, and between the Fifth and Sixth avenue entrances, it is proposed to form a lake of irregular shape, and with an area of 8 or 9 acres. This arrangement has been suggested by the present nature of the ground, which is low and somewhat swampy. It is conceived that, by introducing such an ornamental sheet of water into the composition at this point, the picturesque effect of the bold bluffs that will run down to its edge and overhang it, must be much increased;[10] and that by means of such a natural boundary, this rocky section of the park will be rendered more retired and attractive as a pleasant walk or lounge. The proposed effect of this part of the design, as it will appear from the Fifth avenue entrance, is indicated on study No. 1.[11] [10] NOTE, 1868.—An improvement of the soil and of the skylines of this rocky section, contemplated at the time the plan was made, was last year carried into execution, by means of earth filling on the more prominent summit levels.