118 ECONOMIC ESSAYS IN HONOR OF JOHN BATES CLARK 
of the factors, (3) the degree to which the actual course of wages, 
interest rates, and the proportions of the total product received 
by the factors have conformed to what would be expected from 
our analysis once the elasticities, etc., are known. 
I have for overayear® been attempting to determine inductively 
from English and American experience the probable nature of the 
supply curve of labor and capital. The relationship between the 
short-run supply of labor and the rate of real wages has been 
tested as regards the proportions gainfully employed, the stand- 
ard hours worked, the percentages of absenteeism, turnover, ete. 
The interconnections between the movements of real wages and of 
birth and net fertility rates have also been studied in great 
detail, as have the relationships between real wages and the total 
number of man hours offered for sale. 
The supply curve of capital has also been explored by com- 
puting indexes of the growth of physical capital in both England 
and the United States, and correlating these changes with changes 
in the rate of interest. 
Several other lines of investigation have also been started 
and it is hoped that all of these inductive studies may soon be 
published. It is not pretended, however, that more than a begin- 
ning can be made by any one man. A large group of inductive 
workers is needed to secure the concrete values for the many 
unknowns, and thus put content into what are at present, rather 
empty economic boxes. If this article serves only to indicate 
the nature of the problem, to analyze the forces at work, and to 
stimulate others with the desire of adding concrete material for 
the solution, it will have fulfilled its purpose. 
1 Since the early part of 1925. 
aan 
SIS