2 Faraday, Biological Aspect of Cancer. 



to act in relation to the environment. But, as Lord 

 Salisbury pointed out in his Oxford address to the British 

 Association, there is an essential difference between the 

 inorganic and the living molecules, in that the former do 

 not breed. An elementary inorganic molecule may, by 

 initiating a series of re-combinations, change the character 

 of a solution many times its own weight ; but it will not 

 change the solution into a colony of molecules identical 

 with itself The living molecule decomposes or re-arranges 

 the solution or milieu in which it is immersed ; but it also 

 reproduces an indefinite series of organised beings like 

 itself by actually converting the surrounding material into 

 such organisms. 



There is another characteristic of the living molecules. 

 They have the power of forming associations based on the 

 operation of the economic principle of the division of 

 labour. From this power results differentiation through 

 many intermediate stages into roots, stem, leaves, and the 

 various parts of the flower in the more highly organized 

 plants ; into blood vessels, nerves, ligaments, skin, and the 

 various organs of the more highly organised animals. 

 But, even still, regarded merely as a vital process, that is, 

 leaving out of the question those ethical problems and 

 results involved in the building up of a habitation for the 

 soul of man, and for the exercise of his spiritual powers, 

 the differentiations resolve themselves into merely a more 

 highly complicated method of reproducing the organism. 

 Apparently allied with this power of differentiation is the 

 production of '' sporting " varieties, the complete organism 

 being thus itself liable to variation in its ultimate form, 

 and apparently retaining the power, under certain con- 

 ditions, of reproducing its variations so that the progeny 

 of the most highly organised resultant form tends to 

 reproduce in its own life-history all the differentiations of 



