APPENDIX. 351 
of his labour and time, and some trifling expenses, 
which we shall mention hereafter. 
As to the proprietor, we suppose him, in one in- 
stance, to have had, for a length of time, a suf- 
ficiency of mulberry-trees on his own lands, to obtain 
the given quantity of leaves ; and, on the other hand, 
we suppose the proprietor does not possess trees 
enough, and is desirous of increasing them. 
To obtain 21,000 pounds of mulberry-leaves, the 
proprietor need only have sixty grafted mulberry-trees, 
each producing pounds ; sixty trees producing 
15 pounds ; sixty producing 221 pounds ; sixty 
trees producing 30 pounds ; sixty, producing 37, ! ; 
as many producing 45 pounds ; sixty producing 52£ 
pounds ; sixty producing 60 pounds ; sixty pro- 
ducing 67| pounds ; and ten trees producing 75 
pounds ; — in all, 550 mulberry-trees. And as we 
must take into our consideration, that in these climates 
only one fourth part of these trees can be stripped 
every year, and consequently rests one year, it will 
require 732 trees. 
A property which has for some years afforded 732 
mulberry-trees of various sizes, such as I have de- 
scribed, and in which more are planted every now 
and then, to replace those that die, will yield 21,000 
pounds of leaves. 
There should be round the foot of a thriving mul- 
berry-tree a fallow space of ground, of about four feet 
square, for many years, that the roots may re- 
ceive external air, and draw the nutritious moisture 
