xiv INTRODUCTION 



marked contrast to the perennial character of the matter and 

 the energy which circulate within it. 



The elementary phenomenon of life is the contact 

 between an alimentary liquid and a cell. For the essential 

 phenomenon of life is nutrition, and in order to be assimilated 

 all the elements of an organism must be brought into a state 

 of solution. Hence the study of life may be best begun by the 

 study of those physico-chemical phenomena which result from 

 the contact of two different liquids. Biology is thus hut a 

 branch of the physico-chemistry of liquids; it includes the 

 study of electrolytic and colloidal solutions, and of the 

 molecular forces brought into play by solution, osmosis, 

 diffusion, cohesion, and crystallization. 



In this volume I have endeavoured to give as much of the 

 science of energetics as can be treated without the use of 

 mathematical formulae; the conception of entropy and 

 Carnofs law of thermodynamics are also discussed. 



The phenomena of catalysis and of diastatic fermentation 

 have for the first time been brought under the general laws of 

 energetics. This I have done by showing that catalysis is only 

 one instance of the general law of the transformation of potential 

 into kinetic energy, viz. by the intervention of a foreign 

 exciting and stimulating energy which may be infinitely 

 smaller than the energy it transforms. This conception 

 brings life into line with other catalytic actions, and shows us 

 a living being as a store of potential energy, to be set free 

 by an external stimulus which may also excite sensation. 



In a subsequent chapter I have dealt with the rise ol 

 Synthetic Biology, whose history and methods I have described. 

 It is only of late that the progress of physico-chemical science 

 has enabled us to enter into this field of research, the final one 

 in the evolution of biological science. 



The present work contains some of the earliest results of 

 this synthetic biology. We shall see how it is possible by 

 the mere diffusion of liquids to obtain forms which imitate 

 with the greatest accuracy not only the ordinary cellular 

 tissues, but the more complicated striated structures, such as 

 muscle and mother-of-pearl. We shall also see how it is 



