ON LIFE. WHAT IS IT? 449 



entity equivalent to the " spirit " of theology, and alto- 

 gether undemonstrable by the most finished and scientific 

 methods of research, although clear to " the mind's eye," 

 and acceptable as an article of scientific faith. Nerve 

 energy, in actuating the machinery of life, allies itself with, 

 or actually becomes, muscular energy, operates through 

 capillary attraction and subtle forms of chemico-physio- 

 logical affinity, and accomplishes the dynamics of life by 

 affiliating itself with the physics and chemistry of" organism 

 in action." 



2 F 



