()IIG\N IZATION OF WOOD. 
19 
There are for instance three arrangements 
of woody fibre; the first and most usual, in 
which the sides of the cells are free from 
dots; the second, in which they are spotted 
with minute grains; the third, in which 
they have regular marks or glands. Our 
ordinary woods are composed of the fiist; 
the cycadean tribes and their allies of the 
second; and pine wood of the third. So 
constant and pervading is this distinction, 
that it may be detected even in a fragment 
of fossil wood ; and thus is revealed the for¬ 
mer state, and somewhat of the history of 
an obscure petrifaction. The microscope 
applied to a thin slice of carbonized matter 
sheds light upon its dark structure, and 
claims for it a rank among the pines, or 
palms, or forest trees of the earth. By the 
aid of such examinations most of the results 
of fossil botany have been attained. The 
simplicity of structure, and boundless variety 
of form, afford one of the proofs, so often 
met with in these studies, of the affluence of 
the Creator’s wisdom, as displayed in his 
works. 
Economy of causes, and prodigality of 
effects; simplicity of laws, and complexity 
