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and pumps. Some steps were built spirally into the wall of the well 

 to enable visitors to reach the pump platform. A floor has been laid 

 over the well leaving a circular opening twenty feet in diameter. 

 The floor is supported on two isometrical trusses. The entrance to 

 the well is through the boiler house and a side opening in the wall 

 of the well. 



FORCE MAIN. 



The force main leading from the pump to the reservoir is a cast- 

 iron pipe twelve inches in interior diameter. Its length is to be four 

 hundred and sixty-five feet, and the elevation of the point at which 

 it delivers the water in the reservoir is one hundred and sixty feet 

 above the level of the water in the well, and one hundred and seventy- 

 three feet above tide level. The main was made with bell and spigot 

 joints, the bells being five inches deep, and the lead joints were made 

 only three and one-fourth inches deep, the balance of the space being 

 filled by a hempen gasket. 



The force main delivers the water into the reservoir just above 

 its high-water line. The object in pumping to this height, rather 

 than into the bottom of the reservoir, is to insure a uniform press- 

 ure on the pumps. In the force main near the pump is placed a 

 check-valve. This is a self-acting arrangement, by which the pressure 

 of the water in the main is prevented from acting on the pumps 

 while they are not in motion, and consists of an inclined partition 

 across an enlargement of the pipe, with valves on the upper side, 

 which are opened as the water is forced through them from the 

 pumps, and which are closed by the pressure of the water in the 

 pipe above them. At a distance of eighty-three feet from the well, 

 and at an elevation of about sixty-one feet above the surface of the 

 water in the well, there is a branch connecting with a fifteen-inch 

 vitrified pipe, which leads to the lake near the proposed sight of the 

 refectory. This branch will be used when it is required simply to 

 fill the lake. 



At a distance of one hundred and fifty-four feet from the well, 

 and at an elevation of ninety feet above the water in the well, is 

 another branch connecting with a twelve-inch cast-iron pipe leading 

 around the base of Lookout Hill to the uppermost of a series of 

 pools. This pipe delivers the water at an elevation of one hundred 

 and twenty-four feet, and will be used when a supply of water is to 

 be furnished to the pools and cascades situated in the Ambergill and 

 Nethermead districts. 



It will thus be seen that the water from the well can be delivered 



