THE ORIGIN OF LIFE — UNDISCOVERABLE. 



43 



been green with chlorophyll. If this supposition be right, as soon at 

 the first speck of protoplasm was formed it must then have developed 

 chlorophyll ; but the lowest organisms now existing, with which 

 Haeckel would compare the first living beings, as far as we know 

 have none. They all live upon organic substances, alive or dead, and 

 their products. 



There is yet another contrast. It is a fundamental fact or law 

 that no inanimate mineral, whether solid, liquid or gaseous, if in 

 motion, can direct itself. There must be a vis a tergo, or a directing 

 power, to determine its path ; so, when we see the result of molecular 

 motion, as, e.g., in the development of a thigh-bone with an arched 

 summit in order to support the whole weight of the body, we discover 

 a structure very different from a basin-like depression of clay to which 

 an artesian well can be sunk, however useful that depressed bed of 

 clay may be to stop and hold the water. 



What, then, determines molecular motion ? Mr. James Croll * 

 asked this question in 1872, and says the correct answer will solve the 

 fundamental problem of Nature. 



The only thing that can and does do it is directivity. 



It is this " directivity " of life which alone determines in what 

 organs the several ingredients of the blood shall be deposited, severally. 

 But all this is something over and above the purely metabolic processes, 

 executed with lifeless force and matter, alone. 



McCabe adds : " Another conjecture is that life may be itself 

 a simple and eternal form of energy, like electricity."! If so, we should 

 expect to find it to be interchangeable with other physical forces, 

 according to the principle of the conservation of energy. 



What, then, is the result of this inquiry ? McCabe says, 

 " The evolutionist must assume that something like the [imaginary] 

 biogens [i.e. life-begetters] preceded the microbe in point of time." \ 

 But the supposed biogen is still a particle of plasm ; and we have not 

 in Nature any series of inorganic substances bridging the distance 

 between plasm and inorganic matter, or between imaginary biogens and 

 living microbes. He then alludes to Pfluger's observation that 

 cyanogen (bicarbide of nitrogen), only made by intense heat may have 

 supplied the physical basis of life ; inasmuch as our earth passed 

 through and cooled from a condition of great heat, " Why may not 

 vast quantities of cyanogen or cyanic compounds have been produced 

 at that time ? " then follows an imaginary series of chemical changes 

 involving one " might," one " should," and eight things that " would " 

 occur ; yet the whole is purely imaginary. 



We thus return to our starting-point. The " yawning gulf " is still 

 there, and, so far as we can see, it is likely to remain. 



The whole difficulty lies in the fact that we do not know what life 

 is, nor how it acts or guides forces which cannot guide themselves, 

 nor how it holds chemical forces in its power, making organic substances 



* Philosophical Magazine, July 1872. 



t Op. cit. p. 63. { Op. at. p. 65. 



