564 TEE POPULAR SCIENCE MONTHLY. 



eludes too much vitalism to suit our present purpose, which is to link 

 the organic to the inorganic world. 



We, therefore, cannot allow our scientific inquisitiveness to be ar- 

 rested by the interposition of a mere name, or qualitas occulta. We 

 do not wish to make known to others that contraction actually occurs 

 in the living substance, for that is notorious. We wish to ascertain 

 for ourselves how this contraction is effected whether it is the work 

 of entirely new forces exclusively appertaining to life, or whether it is 

 the mechanical expression of molecular forces, with which we are al- 

 ready familiar in the domain of inorganic activities. Is it a specifically 

 vital force which executes the contraction of motility ? Or is it a 

 molecular activity of a known kind which gives rise to vital motion ? 



This simple question may appear to some very unexciting; yet, 

 upon its answer turns, nevertheless, the entire problem of life ; for it 

 is just at this point that the doom of vitalism has to be sealed. Vital- 

 ism or evolution : these two conceptions of Nature are incompatible. 

 Vitalism means essentially the era of metaphysical agencies, the sway 

 of extraneous powers coercing a resisting world of stubborn matter. 

 Evolution means the era of inherent efficiency, the interaction of intrin- 

 sic powers ever elevating the constant realm of transient existences. 

 It is of great importance, then, not to be deceived with regard to the ex- 

 act manner in which this decisive vital act, the contraction of motility, 

 is at all times being performed in Nature. 



Fortunately, our monera give us plain information upon this point. 

 It can be proved that it is chemical decomposition by which the lique- 

 fied and expanded material of the conical projection is caused to assume 

 its former condition and place in space. The living substance contracts 

 because it suffers decomposition, as can be directly witnessed. On the 

 strength of this observation it would be quite legitimate to infer that 

 it must have been chemical composition which also caused the reverse 

 activity which made a portion of the protoplasm start out from its 

 globular limitation, and form a projection measuring in length in some 

 cases more than three times the diameter of the main body. But \v T e 

 are not reduced to mere inference in this instance, so important to 

 the understanding of vitality. By means of various accompanying ap- 

 pearances we can visibly ascertain that it is really a process of chemical 

 composition which underlies the liquefaction and expansion of motility. 

 This leading property of vitality is brought into actual play by the 

 expansion of a certain substance in course of composition, and by the 

 contraction of the same substance in course of decomposition, expan- 

 sion and contraction being merely the physical concomitants of a defi- 

 nite chemical occurrence. This is shown on the one hand by the 

 products of decomposition being separated and eliminated under our 

 view, and on the other hand by the combining substances being brought 

 together, and effecting their union during inspection. We have no 

 occasion, then, to appeal to the intervention of any specific force in 



