120 iy TRANSACTIONS OF THE ah? aie 
THE THEORY OF THE CONSTITUTION 
OF MATTER. 
BY ORIN TUGMAN. 
For a long period of time scientists have believed 
that all matter is composed of discrete particles called 
molecules. The evidence for the existence of molecules 
is so well established it is considered unnecessary to re- 
peat all the experimental data bearing on that question. 
It is enough to know that molecules have been counted 
not one by one, but experiments have been devised by 
which it is possible to calculate the number of molecules 
in a cubic centimeter of gas with greater precision, says 
Professor Milikan, than it is possible to count the number 
of people living in New York City. The number of mole- 
cules in a cubic centimeter of any gas at a temperature of 
zero degrees centigrade and normal atmosphere pres- 
sure is calculated to be 
N=26.5 x 1078 
with a probable error of only one-tenth of one per cent. 
That molecules are composed of atoms is also a well 
established theory. The great amount of chemical data 
is sufficient for this theory. 
After we have proved the existence of molecules and 
atoms the next logical question is what are the constit- 
uents of atoms. We want to know what is the structure 
of a carbon atom which gives it chemical and physical 
properties different from a nitrogen atom or an atom of 
lead or any other atom. 
This question has not yet been fully answered but the 
research scientists have made a start toward its solution. 
The problem is being attacked from many sides and many 
phenomena which have hitherto been studied without 
thought of atomic structure are now known to be intim- 
ately related to the structure of the atom. 
As in the study of matter attempts were made to 
