291 



lake was protected from the action of the sun during the progress of 

 the work, by a layer of gravel and stone three indies thick. These 

 will also protect the slopes from the action of the waves in Summer. 

 The slopes of the main lake arc made with an inclination of one foot 

 vertical to five feet horizontal. The puddling on the bottom of the 

 lake was covered with water as it was laid, and thus protected from 

 injury by the sun. 



The clayey loam which was used for the lower layer of the 

 puddle was found in great abundance over nearly the entire area to 

 be occupied by the lake, just beneath the surface soil. The blue 

 clay used was found in the Hart range, and is a remarkable deposit. 

 A search was made by borings on all portions of the park where 

 clay was likely to be found, and at this point it was discovered about 

 three feet below the surface. This covering was removed, and the 

 excavation of the clay carried to a depth of twenty-three feet before 

 the bottom of the deposit was reached. Immediately below the clay 

 is a mass of boulders, which rest upon a bed of sand. Over seven 

 thousand yards of clay have been taken from this deposit, and the 

 indications are that a large quantity still remains. 



A temporary dam, with proper weirs, was constructed at the 

 lower end of the completed lake, and the drainage waters of the park, 

 from the fill rains, soon filled the lake to a depth of three feet. From 

 careful daily observations of the water level it has been ascertained 

 that the leakage is so slight as to indicate that the method of pud- 

 dling adopted is entirely successful. 



Two of the Hart Beck pools have been completed, with proper 

 masonry dams, which are covered with rock work. The puddling of 

 these pools consists of but six inches of clay, as the bottoms were 

 of a clayey character. The slopes of the pools are generally three 

 feet horizontal to one foot vertical. 



AGRICULTURAL DRAINAGE. 



But little agricultural drainage has been laid during the season. 

 That laid last year has, almost without exception, proved very effica- 

 cious, and is generally in good working order. 



WATER SUPPLIES. 



The water distribution system has been extended by continuing 

 the six inch main around the lake toward Franklin avenue, and the 

 twelve inch main in the direction of Fifteenth street. The patent 

 cement pipe is still used, and that which was laid last year is in 

 good condition, and requires no repairs. 



