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far larger, but not so numerous as the former. In some 

 trees there are also several rows of tubes, which emit 

 a thick milky liquor. 



6. The Pith is the middle of the wood. It consists 

 of various rows of hollow globules, covered with a fine 

 membrane. In some trees it contains a peculiar juice, 

 which sometimes hardens or grows black. In tender 

 shoots the pith (which is frequently hexagonal) is not 

 exactly in the middle, but is neftper the bark on the 

 south side than on the north side of the plant. It is a 

 constant observation, that the pith lessens as the tree 

 grows. Some have imagined it to be the heart of the 

 plant, but this cannot be; for some trees will flourish 

 and bear fruit after the pith is taken out. Besides 

 this, there is in some trees a blea, a white and a tender 

 substance between the bark and the wood. 



7. The Root has nearly the same vessels as the 

 trunk ; through it the juice passes that nourishes the 

 plant. The roots of some plants are full of hollow 

 threads, which transmit nourishment to the upper 

 parts : this in other plants insinuates itself through the 

 pores that are in the bark of the root. The branches 

 of a plant agree with the trunk in all the essential parts 

 of its structure. 



If no moisture comes to the roots of trees they can. 

 not grow; but if it comes only to the points of the 

 root, though all the rest remain dry, they grow well. 

 For the root shoots out yearly a sharp pointed tender 

 part, somewhat like the sharp bud on the end of a 

 sprig, by which it not only enlarges itself in breadth, 

 as the branches do above, but also receives its nourish, 

 ment, and that tender part moves toward the soft and 

 moist earth ; so that to loosen the earth at the points 

 of the roots, much helps the growth of all plants. 



8. On the smallest part of the branches grow the 

 Leaves; of these we may observe, 1, The fibres of 

 the leaf stand not on the stalk in an even line ? but aU 



