17. The weight of the chain for the length _x_, =
112 0·1143 _x_³
--- _p_ π _x_² --------------;
800 2
18. The height of the water pressure for the highest position, without
the counterweight =
3 _p_ π - 0·1143 _x_
--------------------;
56 π
A Dictionary of Arts, Manufactures and Mines containing a clear exposition of their principles and practice · 第 180 / 421 题