THE ANIMAL AS A PRIME MOVER. 335 



directs it, which is constructed to differentiate it from other energies, 

 to give it form and purpose, to afford it a vehicle, is the spinal nerve of 

 the vertebrate and the equivalent organ in other creatures. 



The psychical energies, including consciousness, intellection, emotion, 

 which are essential characteristics of the vital machine, and which, in 

 the case of those with which we are principally concerned, at least 

 influence to an important degree its power, endurance, and efficiency, 

 all depend for their effective display and fruitful exertion upon the 

 preservation in good health and perfect form of the upper brain. A 

 touch upon the surface of that organ impairs the action of the mind; 

 the destruction of a ganglion takes away the power of expression if not 

 of thought; the lesion or degeneration of its tissue measures a propor- 

 tional loss of psychic energy. With the organ sound and strong, its 

 action depends, as every day's experience shows us, upon its nutrition 

 and repair. Like the body, it is seen to be a machine which guides 

 and applies energies derived from external sources. All its energies 

 come or an initial supply brought through the blood channels from the 

 digested food, and both body and brain exhibit characteristic modes of 

 guidance and application of the transferred and transformed energies 

 originally stored in air and food. Body and brain are apparatus for 

 absorption, transformation, and employment of characteristic forms of 

 energy. Their methods of absorption, modes of transformation, and 

 processes of application constitute important and attractive as well as 

 legitimate problems in physical research. Tracing back the path by 

 which all matter came in from space to construct the material world 

 and retracing the path over which the energies came out of the ether 

 and its accompanying stock of all the energies, are companion problems. 



The origin of energies displayed in the vital machine is found in the 

 food consumed, and the apparatus of the body is simply, as is now well 

 proven, employed in the freeing of these energies from their potential 

 form in the chemical affinities of oxygen for carbon, hydrogen, nitrogen, 

 and the elements of various other compounds, and the diversion and 

 direction of the resultant energies of various kinds and always equiva- 

 lent quantity in the performance of internal and external work. Brain, 

 nerve, muscle, gland, all give proper direction to appropriate energies; 

 none originates energy or has power, intrinsically, of doing work. They 

 are all characteristically and kinematically similar to the organs of the 

 machines constructed by man. But the ultimate physical source of all 

 energies, so far as identified, is the heat and light of the sun; while in 

 turn the source of the energy of the sun's rays is presumed to be the 

 mechanical energy of colliding atoms, molecules, star dust, all celestial 

 bodies, the comets, planets, suns, worlds. The distinctive energies are 

 simply, as we suppose, different modes of motion of atoms and mole- 

 cules and masses, if physical ; but we find no light yet thrown upon the 

 nature of the more subtle energies of vitality, of intellection, of mind, 

 or upon their relation to matter. 



Conclusions of serious import, of singular interest, of engrossing 



