208 



puted with an assumed maximum rainfall of two inches in an hour, 

 and under the supposition that one half of that amount will reach the 

 drains within twenty -four hours. 



Steps have been taked to inaugurate a series of observations upon 

 the rainfall in connection with this system of tile drainage, from 

 which it is expected that valuable information will be obtained in 

 regard to the proportion of rainfall which reaches the tile in a given 

 time. 



None but round pipe tile have been laid, and closely fitting col- 

 lars have been used throughout for the smaller diameter, and even 

 upon the three inch mains whenever they could be obtained. 



The systems were arranged with mains, secondary mains and 

 laterals. The mains were generally three inches in diameter, the 

 secondary mains two inches, and the laterals one and a half inches. 



Generally the mains followed the principal depressions in the 

 surface, the secondary mains, the minor depressions, and the laterals, 

 were laid out at intervals varying from twenty-five to forty-five feet, 

 depending upon the character of the soil, and were nearly at right 

 angles to the secondaries. 



WATER SUPPLY. 



The water supply for the park water-pipe system is at present 

 obtained from the Nassau Water Department. 



A sixteen inch main of this system connects with a twenty inch 

 main of the city distribution at a point near Prospect Hill reservoir. 



This main has branches of various diameters, diverging to differ- 

 ent parts of the park. 



Hydrants are placed at convenient points along the drives for 

 obtaining water for sprinkling the roads, walks and for other pur- 

 poses. 



The patent cement pipe, manufactured by the Patent Water and 

 Gas Pipe Company, of Jersey City, has been adopted. 



It affords me great pleasure to acknowledge the very efficient 

 assistance I have received from Mr. John Bogart and Mr. John Y. 

 Culyer in their respective departments. 



The rapid and uninterrupted progress of the work this season has 

 been facilitated alike by the promptness with which all necessary 

 supplies and material have been furnished by Mr. Culyer, and by 

 the intelligent energy displayed by Mr. Bogart, aided by his efficient 

 corps of assistants, in laying out the work to be executed. 



