Herrick, Physiological Problems. 371 



spot. This trace is projected on a second tuning fork also in varia- 

 tion and the compound harmonic trace on the screen is a resultant 

 not only of the rectilinear motion of the ray reflected in each case but 

 also of the varying rates of motion of the ray producing the trace. 

 The trace is a projection of a composition of motion in space upon a 

 plane and the curious variations observed are very instructive in 

 assisting us to conceive of such a simple process as the combination 

 of O and H to form H2O in dynamic terras. From this illustration 

 the dynamic concept is clearly grasped if w^e admit that whatever 

 type of energy H and O may be respectively (certain directions and 

 rates of motion in our illustration), when these are compounded 

 there results not a somethmo- m which these are somehow bound 

 together but a new direction and a rate of motion or a new locus 

 formula. 



The objection that may be raised that during the process of 

 growth and consequent increase of size there must be an actual 

 increase of substance (and so of matter) in the body is seen to be 

 inapplicable. It is not claimed that any matter is created during 

 growth. It is simply assimilated, i. e., reduced to conformity with 

 the matter already existing in the body. Dynamically expressed 

 this assimilation simply means that the less highly differentiated 

 types of motion of the surrounding inorganic world are affected 

 by the rhythm of the more highly complex organic forces. Im- 

 agine the universe to consist of one homogeneous sea of sluggish 

 activity. Introduce in any way a suitable rhythm at one point 

 and in due course this more vigorous or more rapid rhythm will 

 have imparted itself to the whole universe. It is calculated that, 

 given a suitable medium, the offspring of a single protozoan would 

 in a few years fill the world. We need not contemplate the 

 extreme case but in our own bodies the same law is manifest, the 

 limitations giving rise to an equilibrium between trophism and 

 resistance being more various than in the protozoan. 



Naegeli says that "the configuration of the idioplasm is rather 

 a phylogenetic than a geometric problem. The development of 

 the anlage in the main conforms to this phylogenetic arrangement. 

 By reason of the fact that the organism in its ontogeny successively 

 passes through those stages through which its phylum passed, the 

 idioplasmic anlages appear in the same order in which they origi- 

 nated" {op. cit., p. 50). Naegeli was also perhaps the only writer of 

 the mechanical school to discuss clearly the possibility of modifica- 



