Part IV.] 
PRUNING AND THINNING. 
245 
your hands pass over 100 feet of rope; and, for 
every foot your hands ascend, your body only 
ascends half a foot, and your hands descend 
again half a foot. Again, if you haul a weight 
up to a bough by a double rope fifty feet from 
the ground, fifty feet of rope will pass through 
your hands, and no mechanical advantage is 
gained. But if you haul yourself up fifty feet 
by a double rope, 100 feet of rope will pass 
through your hands; and as in ascending the 
whole space the hands will pass over twice the 
space of rope, so at any particular part of the as¬ 
cent they will require only half the exertion. 
The saw should have a loop to the handle, so 
as to hang on your arm while climbing. A rope 
or belt round the tree and your body, which you 
can lean back against while at work, adds infi¬ 
nitely to your power. 
March and April are my two months for prun¬ 
ing trees which do not bleed. At that time 
branches have returned their downward sap for 
the nutriment of the root, and have scarcely yet 
begun to receive the new supply upward, and 
they will bequeath their annual share of this to 
the leader and other heirs of your choosing; and, 
the leaves being off, you can clearly see to which 
the talents should be entrusted. 
r a 
Best time for 
pruning. 
