WONDERS OF THE MICROSCOPE. 
278 
organs of animals visible to the unassisted eye. While little^ 
if any, anatomical analogy is discoverable between the larger 
parts of animals and plants, the closest ties of organization 
are exhibited by the microscope in the minute sections; and 
it is demonstrable, as we shall hereafter attempt to show, 
that a unity of plan in structure and development may be 
traced throughout the organic world. 
In organized beings nature works out her most secret 
processes through structures too minute for observation 
unless by the assistance of the microscope. The microscope 
widens and extends the power of vision, and creates a new 
world of observation. By it that which the unaided mind 
could only imagine, or vaguely indicate as a possible exist¬ 
ence, is demonstrated, and the structure which was a puzzle 
and a mystery becomes perfectly understood. When we 
inspect with our unaided vision any animal or plant, we 
detect a variety of evidences of organization or structure; but 
there is in every part of every vegetable or animal production 
an almost infinite amount of organization wholly invisible to 
the unassisted sight, and which is revealed only by the 
powers of the microscope. 
The vegetable and animal kingdoms, with a wonderful dis¬ 
tinction in form and function, have yet relations so close, and 
a dependence so absolute, that the principles which regulate 
the growth and functions of one cannot be understood without 
reference to the other, and researches prosecuted by the aid 
of the microscope are every day increasing our knowledge of 
the details of this great fact. 
It is only a few years ago that the existence of cells 
in plants, if not altogether ignored, was regarded as a 
matter of little or no consequence, and vegetable phy¬ 
siologists speculated on the functions of plants, without 
knowing anything of the agencies by which they were 
produced. Microscopic research has, however, shown us 
that it is in the interior of these minute constituents of 
vegetable tissue that all the functions of plants are carried on. 
Hence we may truly say that the principles of the anatomy 
and physiology of the vegetable cells are the principles of 
vegetable anatomy and physiology. 
By the aid of the microscope the physiologist is able to 
study the several organs of which vegetables are composed. 
If, for instance, it is desired to ascertain the mode of growth 
in cells, we may appeal to the simple Algae. Here the 
observer may trace, step by step, the division of the “ primi¬ 
tive mother cells/ 5 with nothing to prevent his view; or, if 
he takes one of the simple Conferva, he can ascertain exactly 
xxxii. S7 
