THE CARBON THEORY. 335 



on the material nature of the organism, just as all the 

 physical and chemical qualities of every crystal are 

 determined solely by its material composition. Now, as 

 the elementary substance which determines the peculiar 

 material composition of organisms is carbon, we nmst 

 ultimately reduce all vital phenomena, and, above all, the 

 two fundamental phenomena of nutrition and propagation 

 to the properties of the carbon. The peculiar-chemico- 

 physical properties, and especially the semi-Jiuid state oj 

 aggregation, and the easy decomposihility of the exceedingly 

 composite albuminous combinations of carbon, are the 

 m^echanical causes of those peculiar phenomena of motion 

 which distinguish organisms from anorgana, and luhich 

 in a narrow sense are usually called " life!' 



In order to understand this " carbon theory',' which I have 

 established in detail in the second book of my General 

 Morphology, it is necessary, above all things, closely to 

 examine those phenomena of motion which are common to 

 both groups of natural bodies. First among them is the 

 process of growth. If we cause any inorganic solution of 

 salt slowly to evaporate, crystals are formed in it, which 

 slowly increase in size during the continued evaporation of 

 the water. This process of growth arises from the fact 

 that new particles continually pass over from the fluid state 

 of aggregation into the solid, and, according to certain laws, 

 deposit themselves upon the firm kernel of the crystal 

 already formed. From such an apposition of particles arise 

 the mathematically definite crystalline shapes. In like 

 manner the growth of organisms takes place by the accession 

 of new particles. The only difference is that in the growth 

 of organisms, in consequence of their semi-fiuid state of 



