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material was found, this was removed to a depth of six inches, and 

 replaced with gravel or sand. All of the tar walks laid last year 

 have proved satisfactory in all respects. They have not been injuri- 

 ously affected either by heat or cold, and the expense of maintenance 

 has been very slight, for the surfaces have not required renewal, roll- 

 ing or sprinkling. The heaviest lains have not damaged them in the 

 slightest degree. 



The surface water as it flows from these walks into the silt basins, 

 carries no sediment with it, and this incidentally produces a great 

 saving of expense in the care of silt basins and sewerage systems, as 

 so much less material has to be removed from them. The walks 

 made last year which were surfaced with fine screenings from the 

 McAdam stone, did not prove satisfactory, as the smaller particles 

 washed away, leaving the larger and angular fragments on the sur- 

 face, and these were unpleasant to walk upon. The gravel walks laid 

 this season were surfaced with Roa Hook gravel, in all other respects 

 they were made like the stone-dust walks of last year. 



THE LAKE. 



Work upon the lake has been vigorously prosecuted during the 

 season, and all of the portion above the great concourse, comprising • 

 more than twelve acres of water surface, has been completed. The 

 bottom of the lake, over almost the entire area excavated, is com- 

 posed of coarse sand or gravel, than which nothing can be more un- 

 suitable for retaining water. The drainings from the park surface 

 nearly all tend towards the lake, and at times, during the progress 

 of the excavation, the water from heavy storms accumulated to a 

 depth of from one to two feet, but owing to the exceeding porous 

 nature of the bottom, the entire quantity filtered away in a few 

 hours. There being no natural supply of water on the park except 

 surface drainage, it became a matter of vital importance to make an 

 artificial bottom to the lake, which should be as nearly impervious 

 to water as possible. This was done as follows : the excavation was 

 carried to a depth of one foot below the final bottom of the lake, and 

 a layer six inches in thickness of stiff clayey loam was laid on evenly, 

 and carted over and otherwise worked, without special care ; upon 

 this was laid six inches of blue clay of very fair quality, as it was 

 found in the pit, without other mixture with sand and gravel. This 

 layer of clay was thoroughly wet, and carefully cut and worked over 

 with shovels, care being taken to have the water and working reach 

 the lower layer of clayey loam. The puddling on the slopes of the 



