May 27, 1898.] 



SCIENCE. 



725 



2. The atomic matter whicli flows into 

 the organism in metabolism suifers change, 

 both molecular and in mass, without inter- 

 fering with the continuous operation of the 

 genetic phenomena of the organism as a 

 whole. 



3. The energy which is added to that of 

 the organism by way of this acquired 

 matter does not determine the course of the 

 genetic phenomena, since, as has been 

 said, the same matter behaves differently as 

 it enters different organisms, and different 

 matter is made to behave according to the 

 law of the organism which it unites with. 



4. The thing transmitted from parent to 

 offspring, through which alone we are able 

 to trace the determining power of the ge- 

 netic phenomena in each case, cannot be 

 matter alone, for matter is in itself inert; as 

 Maxwell tells us : " We are acquainted 

 with matter only as that which may have 

 energy communicated to it from other mat- 

 ter, and which may, in its turn, communi- 

 ■cate energy to other matter. Energy, on 

 the other hand, we know only as that which 

 in all natural phenomena is constantly pass- 

 ing from one portion of matter to another." 

 {' Matter and Motion,' p. 165, 1878.) 



5. Hence it follows that that which de- 

 termines the individuality of the genetic 

 phenomena of a living body, constitutes the 

 integrity of the organism as distinct from 

 a mass of matter, and preserves its iden- 

 tity through all the changes it undergoes, 

 is energy, not matter. 



6. A living organism physically behaves, 

 not like an identical mass of matter, but 

 like a stream of matter slowlj' entering and 

 departing from the field of some continuous, 

 identical form of energy. It behaves like 

 a magnet, or a heated body, the phenomena 

 exhibted by which are temporary and de- 

 termined by what is called a particular form 

 of energy resident for the time in the mass, 

 and not determined by the particular ma- 

 terials, or arrangement of materials, of 



which the body is composed.. Whenever 

 the non-living matter from outside enters 

 the living organism it exhibits for the first 

 time the vital phenomena, and when it 

 passes out of the field of the organism these 

 peculiar phenomena cease and are not set 

 up again till the matter comes again into 

 the field of a living organism. Thus the 

 physicist explains the color of an opaque 

 object, not as the property of the material 

 body as such, but as a phenomenon pro- 

 duced by the reflection of light energy by 

 the body. The matter has color only as 

 illuminated from without by light energy. 



A GENETIC FOEM OF ENERGY. 



This train of analysis leads to the recog- 

 nition of a genetic form of energy, on the princi- 

 ple of classification used in physical science. 

 The physicist already recognizes the three 

 forms — chemical, molecular and molar en- 

 ergy. The basis of that classification is the 

 distinction between the three kinds of ma- 

 terial units whose relation to each other, in 

 each case, is disturbed in the phenomenal 

 expression of energy of the several forms. 

 Chemical energy is expressed when the re- 

 lation of atoms changes. Molecular energy 

 is the form of the energy when molecules 

 change their relations ; and it is molar 

 energy which is exhibited when bodies or 

 masses of matter change their positions in 

 relation to each other. The genetic phe- 

 nomena, above described, differ from the 

 phenomena of each of the three classes 

 named in that they concern changes of re- 

 lation of living organic bodies only. It 

 seems, therefore, appropriate, on this basis 

 of classification, to speak of genetic energy 

 as a fourth form of energy of equal rank 

 with the chemical, molecular and molar 

 energies of the physicist. 



The recognition of this peculiarity of 

 genetic energy gives at once rational mean- 

 ing to such terms as doing, varying, acquir- 

 ing, etc., which are appropriate when ap- 



