THE ORGANISM AS A MECHANISM 61 



fact we do not obtain these theoretical conversions, 

 for some of the electrical energy is dissipated when we 

 employ the machine as a motor, and some of the 

 mechanical energy is likewise dissipated when we 

 employ it as a dynamo. 



The entity that we call energy is the product of 

 two factors, a capacity-factor and an intensity-factor. 

 Thus : — 



Mechanical energy of water power = quantity of water x height at which it is 



situated above the water-motor. 



Energy of an electric current = quantity of electricity x electrical potential. 



Chemical energy = equivalent weight of the substance x 



chemical potential. 



What is it that determines whether or not an 

 energy-transformation will occur ? It is the condition 

 that a difference of the intensity-factors of the energy 

 in different parts of a system exists. Water will flow 

 from a higher to a lower level, doing work as it flows, 

 if it is directed through a motor. Electricity will flow 

 if there is a difference of electrical potential. A 

 chemical reaction will occur if two substances before 

 interacting possess greater chemical potential than do 

 the products which may possibly be formed during 

 the interaction. Coal and oxygen possess greater 

 chemical potential than do carbon dioxide and water, 

 therefore they will combine, forming carbon dioxide 

 and water. Energy-transformations will therefore 

 occur wherever it is possible that differences of intensity 

 or potential can become abolished. The energy that 

 may thus flow from a condition of high to a condition 

 of low potential, undergoing a transformation as it 

 flows, is the available energy of the system of bodies 

 in which it is contained. A closed vessel surrounded 

 by an envelope impervious to heat, and containing a 

 mixture of oxygen and hydrogen, is an isolated system 



