DETAILS OF CONSTRUCTION. 



In working the force this year, one main object has been to com- 

 plete unfinished work in various parts of the Park, as far as possible. 



WORK IN VICINITY OF THE PLAZA. 



The unfinished portion of the Plaza at its junction with Union 

 street, has been graded and paved with Belgian pavement ; the curb 

 has been set from this point to the junction of 9th Avenue and the 

 Plaza, and the pavement laid from the latter point down to the head 

 of the west mound. 



The Plaza street has been put in temporary repair for the better 

 accommodation of travel, and a part of the permanent planting put 

 in. 



The picket fence at the entrance has been replaced by an iron 

 rail of galvanized pipe 1| inches in diameter, with locust, posts. 

 This fence is so set as to provide a sidewalk of SO feet in width. An 

 iron cover has been placed on the overflow chamber of the fountain. 



ARCHWAYS AND BRIDGES. 



CLEFT RIDGE SPAN. 



This archway is constructed of Beton Coignet (a concrete of su- 

 perior manufacture), under a contract with the N. Y. and L. I. 

 Coignet Stone Company, Dr. J. C. Goodridge, jun., Superintendent. 



The work was commenced ia the month of September, and is 

 now nearly finished. Its location is at the easterly end 'of Breeze 

 Hill, and the archway carries the main walk from the Plaza, under 

 the drive, to the pedestrian concourse. Its span is 20 feet, and 

 length CG feet. The exposed surfaces are made up of block courses 

 of this material, formed in moulds, and much of this work is of an 

 ornamental character. The foundation and backing are monolithic. 



The process of manufacturing this material is, briefly, as follows : 

 Certain proportions of lime, cement, and sand with sufficient quan- 

 tity of water to form a hydrate of lime, arc thoroughly incorporated 

 by machinery, the material on which the coloring depends being in- 

 troduced at the same time. To secure excellence in fabrication, it is 

 found necessary to regulate in a systematic manner the water re- 

 quired. Great stress is therefore laid upon the fact that, the quan- 

 tity of water must not exceed what is barely sufficient " to convert 

 the ' matrix ' into a stiff viscous paste ;" each grain of sand, gravel, 

 or particles of broken stone must also be sufficiently covered with 



