146 BOARD OF AGRICULTURE. 



The cell was taken as the groundwork of my scheme, for 

 microscopic study had familiarized me with these unities of 

 vitalized structure, and belief in a reign of law had led me to 

 a firm conviction that the working of natural law was univer- 

 sal ; and if completed structure was governed by any power, 

 then the individual parts of that structure must be influenced 

 by the same ruling. Hence the search after truth must be 

 from the simple to the complex, rather than the reverse. 



Every change of matter must be produced or caused by 

 some previous condition, for every effect must have its cause. 

 This which accomplishes is called a force, and the change 

 is the measure and exponent of the force used. Force is, 

 therefore, a conception of a real existence, which, although 

 unseen to our eyes, and not cognizable to our senses, can be 

 studied from its effects, for these are seen and recognized, 

 and may be grouped ; they can in turn be converted into 

 the unseen, and again be reconverted into the seen, and, 

 through modern science, so measured and accounted for, 

 that it may be said with certainty, forces are indestructible. 

 Forces are also strictly subject to the law of quantity. 

 A given quantity of one force can produce a definite 

 quantity of another. The conversion of a force may change 

 its apparent character, and the phenomena produced by 

 the two forms may be widely different. This is illustrated 

 in heat and motion, electricity and magnetism, animal and 

 vegetable life. 



Like causes produce like effects when acting in a similar 

 manner on similar material. We know that forces may be 

 represented by forms, and that difference of form will indi- 

 cate a difference in the construction of the force. 



Force is the agent which produces changes. It has, as a 

 conception, a numerical value and a direction of action. It 

 can, therefore, be increased or diminished, and its direction 

 may be interfered with or antagonized by other force. The 

 concrete force is the equilibrium of all these opposing forces. 

 Any change must be produced by an equivalent change in the 

 force which is represented by the object undergoing change. 



This work is but applying the doctrine of persistence of 

 force to vitality, as it has already been applied to physics. 

 The forces governing vitality, chemistry and physics, must 



