Then the tree perspires in the same manner that we do: that is odd. But what is the middle pulpy bark, with its green colour and sticky feeling?
Botanists call that the Chlorophyll or colouring matter. The inner bark is the liber, which you see to be soft and fibrous like, being full of sap.
Why, this is something like our skin, as there is a watery stuff between our cuticle and the skin that has the blood in it. I have heard of people writing on bark: that must have been on the liber.
It was so. The English wrote on the bok or bark, and thus we have the word book; while with liber we connect the word library. But we shall return to the liber in another lesson.
Is the cuticle always naked?
No, some plants I have seen with hair over the skin, and others with something like scales.
Having talked of the bark, boy, we will turn to the stem. What are your notions about it?
My eyes and fingers tell me that, after I pass the liber of the bark, I reach the fresh-looking white ring of wood, and that after that the wood which is still in rings gets harder and drier toward the centre. But I thought there was pith in the middle of a tree: how is it there is none seen here?
Because these woody layers or rings have crushed it in time. I must say a little about this pith. You know it is soft enough; that is, because it is composed of small cells filled with juices at first, and then with air.