llG li:tter X. 



moving at the same instant, but without the slightest 

 interference with each other. 



Can any thing be more admirably adjusted than all 

 this ? By means of a system of tubes and cells va- 

 riously arranged, the whole of the important business 

 of the conveyance of food to the leaves, and of the 

 peculiar properties formed there from the leaves to 

 the centre of the stem, and down to the extremest 

 roots, is carried on in the most certain and effectual 

 manner, even in the loftiest and most gigantic forest 

 trees. Only conceive what a wonderful combination 

 of powers must be provided to enable a tiny leaf, not 

 perhaps half an inch long, on the highest branch of 

 a tree, to procure its food from roots sometimes 250 

 feet off, or at a distance equal to six thousand times 

 its own length. 



But I must not dwell further upon this subject, in- 

 teresting as it is ; to works on Vegetable Physiology 

 you must refer for a full elucidation of all such 

 matters. 



Bearing in mind, that the Oak tribe is constantly 

 known by its imperfect apetalous flowers, and its 

 singular involucre, you are in no danger of forgetting 

 it. Formerly, the Birch and Alder, the Poplar and 

 Willow, and the Plane, were considered as also be- 

 longing to it ; and the whole w ere called Amentaceous^ 

 because of their stamen-bearing flowers being con- 

 stantly arranged in catkins, or amenta, as they are 

 technically designated. But these trees are so ex- 

 tremely dissimilar in other respects, that they now 

 form several independent tribes. 



