53 



ready for the plates and roof. The outer walls are of broken Ashlar 

 masonry, formed of small sized stones obtained by breaking boulders 

 found on the Park. The trimmings are of mountain Graywacke and 

 Ohio stone. The interior walls are of brick, and are finished. 



* WALKS. 



The greater portion of the walks made during the year have been 

 surfaced with pine tar concrete, laid under a contract with the Fiske 

 Patent Pavement Flagging Company. The cost for preparing the 

 substructure for the tar walks has been materially reduced this season, 

 as the concrete was laid upon the natural soil, wherever it was of tol- 

 erably porous material. In sections where a clayey or retentive ma- 

 terial was found, this was removed to a depth of six inches and re- 

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

 proved satisfactory in all respects. They have not been injuriously 

 effected either by heat or cold, and the expense of maintainance has 

 been very slight, for the surfaces have not required renewal, rolling, or 

 sprinkling. The heaviest rains 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 surface, and these 

 were unpleasant to walk upon. The gravel walks laid this season were 

 surfaced with Eoa 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 composed 

 of coarse sand or gravel, than which nothing could be more unsuitable 

 for retaining water. The drainings from the Park surface nearly all 

 tend towards the Lake, and at times, during the progress of the exca- 

 vation, the water from heavy storms accumulated to a depth of from 

 one to two feet, but owing to the exceeding porous nature of the bot- 



