region beyond the visible red. To satisfy these conditions Professor Max 
Planck proposed a modification as follows: 
Gere 
Sone af C and © are constant. 
i o where ¢ base of natural log. 
¢O@rA-1 
As far as recent determinations have been carried out, this law holds true 
and gives practically a complete energy curve of a black body for desired 
temperatures. Not only did the statement of this law serve to reconcile 
purely theoretical conclusions with experimental determinations but paved 
the way for a more advanced step toward the explanation of the mechanism 
involved in radiation. 
It is evident that we have yet to establish the connecting link between 
the thermal condition of a body and the radiant energy sent out into space 
by that body. If we go back to the theory developed by Maxwell we can 
easily see how this energy is propagated when once started in the ether. 
This theory clearly accounts for its speed, for interference and diffraction 
phenomena, but it apparently fails to closely associate thermal condition 
and the subsequent radiant energy. Planck found that this formula did not 
satisfactorily represent the relation existing between the frequency and the 
amount of energy involved, i. e. why, as a body grows hotter, does its color 
change from dull red to yellow and then white, unless there was some definite 
mathematical relation existing between the frequency and amount of energy 
given out by each vibratory particle. In an endeavor to determine this 
relation, Planck was led to advance the Quantum theory or hypothesis wherein 
he develops a type of function which apparently agrees with the facts better 
than any theories previously held. In doing this he has made a unique 
assumption, leaving the idea of the equi--partition of energy so necessary 
to the former theories, he has put forth the idea of the distribution of energy 
among the molecules of a substance through a mathematical consideration 
of probability. It is interesting to note in this connection that Planck states 
that the reason why no absolute proof of the second law of thermo-dynamies 
has ever been given is that it rests not on unchangeable mathematical 
relations, but upon mere probability or chance. Following out this idea he 
assumes that there may not be a steady, uniform flow of energy from a 
heated body, but that this may be propelled outward in quantities which 
