CHAPTER I. 



ON THE GROWTH AND STRUCTURE OF TREES. 



The stems of Dicotyledonous and Coniferous* trees 

 may be described as of comparatively uniform structure 

 and mode of increase, and are usually very firm, yielding^ 

 the most solid and best description of timber, their 

 solidity and strength fitting them admirably for use in 

 carpentry, and for many domestic purposes. 



The most common form of stem is the cylindrical, 

 but it is occasionally found grooved or fluted, and not 

 unfrequently flattened, approximating to an oval ; the 

 cylindrical form being, for most purposes, the best for 

 conversion into beams, joists, boards, etc. 



Botanists speak of the stem as the " ascending axis " 

 of a tree, from its taking an upward direction and giving 

 off branches. In the Elm, these branches take an 

 oblique upward direction; in the Birch, they are also 

 oblique, slightly pendulous, and flexible ; those of the 



* Dicotyledons and Conifers are trees, etc., which augment their woody- 

 structures by periodic additions to the outside of that which is first formed ; 

 as long, therefore, as they grow a new layer of wood is normally added to 

 the outside of the previous growth. The Monocotyledons — i.e. Palms, etc., 

 etc. — differ from the above, in having their woody structures formed in suc- 

 cessive strands, so isolated in softer cellular material as to be almost useless 

 for timber. To a certain extent the stems of Tree-ferns resemble the latter 

 in this particular. 



