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element” constitutes the essence, or is the source, of the 
elastic forces in all ponderable bodies — a question here 
passed by. 
Besides the above mechanical forces, we have to consider 
the two other forces, namely, the chemical and vital forces. 
The affinities and repulsions of the component parts of 
matter, by which its mutations are affected, constitute the 
chemical forces. These forces are of varying and complex 
intensities, and are still but vaguely understood even by 
our most able practical chemists ; yet the reality of such 
forces is extensively evidenced to our senses, though they are 
seldom such as can be distinctly measured like the mechani- 
cal forces. 
With respect to the vital forces, they are of a still more 
complex and recondite nature, and we must be content in 
our present state of knowledge to place these forces among 
the many other sublime and mysterious laws impressed 
upon organic matter by an all- wise Providence, and which 
are not yet placed within the range of man’s mental vision. 
We simply know that the vital forces are, in part, controlled 
by the will, and a greater portion of them are called into 
action by organic stimulants ; and since both kinds of action 
cease with death, they are properly treated as vital forces. 
Whilst we know not how the vital forces control the me- 
chanical and chemical forces exerted in and by living beings, 
there is no lack of proof that they do in fact command the 
other forces exerted through organic nature. 
I shall here cite an eloquent passage from an essay (given 
in a popular journal, Once a Week, for 13th October, 1865) 
by one of the most able exponents of what is called the 
“New Philosophy,” as follows, namely : — “The great philo- 
sophical doctrine of the present era of science, as the conser- 
vation of energy has been worthily styled — teaches us that 
the activity which we see manifested in all the natural 
forces is a constant quantity, or in other words, that there 
