Nor is this the only care, the thriving 
and fertility of plants and trees depends much 
upon the happy influence and concurrence 
of a great variety of other circumftances. 
Thus many trees are unfruitful by being 
planted too deep, whereby their roots being 
in too moifl: a ftate, and too far from the 
proper influence of the Sun, whofe power 
greatly decreafes the deeper we go, as we 
fee in Experiment 20. they imbibe too much 
crude moifture, which tho’ produdive of 
wood, is yet unkindly for fruit. 
Or if when not planted too deep, they 
are full of crude fap, either by being too 
luxurious, or too much fliaded ; or are plan- 
ted in a moifl, when they delight in a dry 
foil, then the fap is not fo fufficicntly di- 
gefled by the Sun’s warmth, as to be in 
that dudile ftate, which is proper for the 
producing of fruit. 
And thus the Vine, which is known to 
thrive well in a dry, gravelly, rocky foil, 
will not be fo fruitful in a moifl, ftifF, clay 
ground ; And accordingly we may obferve 
in Experiment the 3d, that tho’ the Vine 
imbibed and perfpired more than the Ever- 
green, yet it perfpired lefs than the Apple- 
tree, 
