THE CELL AND PROTOPLASM. 151 



a machine, and its parts are separate machines. 

 Each part is further made up of still smaller 

 machines until we reach the realm of the micro- 

 scope. Here still we find the same story. Even 

 the parts formerly called units prove to be 

 machines, and when we recognize the complexity 

 of these cells and their marvellous activities, we 

 are ready to believe that we may find . still 

 further machines within. And thus vital activity 

 is reduced to a complex of machines, all acting 

 in harmony with each other to produce together 

 the one result life. 



