EYTHM OF MOTION. 183 



concrete in the offspring, is but at first a transference of 

 forces possessed by the parent. To illustrate more fully : 

 the piece clipped from a polype is but a portion of the polype 

 formed by the same forces, and its development impressed by 

 the same force which caused the development of the body 

 from which it was derived. Therefore, in the absence of 

 counteracting influences, there must be resemblance between 

 the two pieces, the parent and the new individual, — the off- 

 shoot. The law of variation is also a development under this 

 law ; for causation, being universal, and the environment 

 under constant change, it is inconceivable that two individuals 

 should be exact counterparts of each other, no matter how 

 near their kinship. Thus constant changes produce corre- 

 sponding variations, and, so long as vitality exists, there is a 

 constant effort on the part of living structure to maintain 

 itself in equilibrium with the various forces affecting it, and 

 we hence have the possibility of evolution. In the phrase, 

 heredity with variation, we have an expression for conditions 

 which are unmistakably directed and ruled by law. 



On a general law of vital periodicity . — Herbert Spencer, in 

 his "First Principles," devotes a chapter to the Rythm of 

 Motion, in which he develops the fact that all changes appear 

 to possess a periodicity of character, and that wherever there 

 is a conflict of forces not in equilibrium, a rythm results ; yet 

 as motion is never absolutely rectilinear, rythm is necessarily 

 incomplete. We find this same law exemplified in animals, — 

 the vital functions all tending to run their course in fixed and 

 recurrent periods, as illustrated by gestation and the phenom- 

 ena accompanying it, certain processes of development, etc. 

 In like manner, as the geysers of Iceland are intermittent, — 

 their spoutings ceasing, until, in process of time, sufficient 

 forces are accumulated to overcome the resistance of the 

 column of water which is expelled by the explosion, — so are 

 certain vital actions which require the expenditure of much 

 power, and even as is a priori probable, all actions whatso- 

 ever have a period of apparent quietude while they are accu- 

 mulating the forces necessary for overcoming the antagonistic 

 forces which they meet ; for conflicts are continually occurring 

 in nature, and a struggle exists, real, although often unnoticed, 

 to maintain that constant equilibrium which is the objective 



