SAP

The fluid which is absorbed by the roots from the earth, then sent Upwards into the stem, and afterwards conveyed from the leaves, where it is a imilated and altered,to the bark. In its crude state it consists of little except water holding earthy and gaseous matter in solution, especially carbonic acid; but as it rises through the ti ue of the stem it di olves the secretions it meets within its course, and thus acquires new properties, so that by the time it reaches the leaves it is entirely different from its stale when it first enters the root. The course taken by the sap in its pa age through the stem is by the whole of the ti ue included within the bark, provided it is all permeable; but as, in many plants, the central part of the stem becomes choked up with solid matter deposited in the ti ue, it usually happens, especially in trees, that the course of the sap Is confined to the outer part of the wood, hence called sap- [s. 1101]