8 
PRACTICAL' PART 
ladder against a tree. A common ladder must 
have four bearings; and if either of these should 
give way, the ladder will turn over. A wide- 
based ladder needs only three bearings; that is, 
it is as safe from turning over with one bearing 
above as with two. 
DESCRIPTION OF WATER-CASK. 
I have found the following sort of water-cask 
very useful; either for common watering, or for 
the conveyance of liquid manures : 
A pair of old gig wheels, four feet in diameter. 
A thirty-six gallon cask, thirty-two inches high. 
Swing this cask between the wheels by two iron 
arms, fifteen inches of the cask above the arms, 
seventeen inches below them. Or the arms 
which pass through the boxes of the wheels 
may be attached to an iron circle large enough 
to receive the cask, which will rest on the circle 
by three supports. 
An iron handle to pass over the top of the 
cask, and sufficiently free from the cask to allow 
of its being tilted. The handle to take on and 
off the axle with a hook and screw. 
A pair of old gig shafts to take on and off the 
handle. 
