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WORK NOT WORRY. 
of the cells, by the aggregation of which any individual 
among the higher plants is formed, has an independent life 
of its own, besides the incidental life which it possesses as a 
part of the organism at large ; so that the life history of the 
individual cell is, therefore, the very first, and absolutely 
indispensable basis, not only for vegetable physiology, 
but for the science of life in general. The first problem 
to be investigated is, “How does the cell itself originate V’ 
Schwann, in 1839, first applied the doctrine that each 
integral part of the animal body possesses an independent 
life of its own, in virtue of which it performs a series of actions 
peculiar to itself, provided that the conditions of these actions 
be supplied ; yet it derived a new significance from the idea 
with which he connected it—that the integral parts are either 
cells, or derived from cells , and that their independent life is 
therefore cell life. This idea was based on the results of 
microscopic observations on the development of the animal 
tissues. For Schwann found that however diverse may be 
the structure and actions of the component parts of the 
animal organism in their fully developed condition, there is a 
period in its history when it is nothing else than an ag¬ 
gregation of cells, all apparently similar to each other; and 
as in some of the tissues—for example, in the blood— 
corpuscles, fat, cartilage, epidermis, epithelium, and the gray 
matter of the nervous centres, the cellular character is pre¬ 
served through life. This was the problem which Schwann 
set himself to elucidate, and which it has been generally con¬ 
ceded that he did much to solve. 
(To he continued.) 
WORK NOT WORRY. 
It is not work that kills men ; it is worry. Work is healthy; 
you can hardly put more upon a man than he can bear. 
Worry is rust upon the blade. It is not the revolution that 
destroys the machinery, but the friction. Fear secretes acids; 
but love and trust are sweet juices .—Henry Ward Beecheds 
Life Thoughts . 
