chap, x.] FOUNTAINS. 345 
( 
which the water will rise. If a cistern be 
formed on the top of a summer-house, ten 
feet and a half high* and a pipe from that be 
carried down a sufficient depth into the 
ground to secure it from frost, and thence 
horizontally to the orifice which is to form 
the fountain, that orifice, if it be only half an 
inch in diameter, will throw up a jet of 
water ten feet high, and will continue play¬ 
ing till all the water in the cistern is ex¬ 
hausted. The conducting pipe for such a 
fountain should be two inches and a quarter 
in diameter, and it should be furnished with 
a valve or stop-cock, which may be turned 
at pleasure, and by which the water may be 
either suffered to ascend through the orifice, 
or retained in the conducting pipe. The 
reservoir cistern must be kept full by a 
forcing pump, or hydraulic ram; or, in the 
neighbourhood of London, by high service 
from the water company which supplies the 
dwelling. Any cistern, sufficiently high 
above the garden, will do. Where a cistern 
in the roof is supplied with a high service 
pipe, a fountain with a jet thirty or forty 
feet high, according to the height of the 
