128 ECONOMIC ESSAYS IN HONOR OF JOHN BATES CLARK 
pleasant neighborhood, congenial neighbors, and all other 
qualities which add to the pleasure and comforts of living. The 
amenities arise mainly from the use of land for residences, either 
urban or rural. In some cases a considerable part of the value 
of land consists of so-called “amenity value.” This does not 
hold true in the same degree in the case of most other forms of 
income. 
In this connection it will be seen that land economics, which 
has been developed largely as a result of observation, statistical 
inquiry and research, is reaching conclusions in regard to the 
income of land similar to those formulated years ago by Professor 
John Bates Clark. Now Professor Clark’s works give a splendid 
illustration of deductive reasoning of a high order. It should be 
particularly gratifying to Professor Clark to find that some of 
those who started out, as the present writer did, with views very 
much opposed to his have been forced by their own independent 
researches to approach his views. The writer would not say that 
he has reached entire agreement with Professor Clark. He has 
come far closer to an agreement and acknowledges a growing 
appreciation of the work that Professor Clark has done. 
One of the things that is urgently needed in the interest of 
theory and practice now is careful research into the increments 
in land values and their causes, as well as into decrements and 
their causes. Some investigations have been conducted in New 
York City, showing that through a long period of years the 
increments in vacant land values were less than the rate of 
interest paid on deposits in savings banks. We find very gen- 
erally in economic treatises, and especially in popular discussions, 
the idea advanced that an increase in population means an 
increase in land values. The researches that have been conducted 
do not bear this out. So far as urban land is concerned, there 
may be a very considerable increase in population with stationary 
or even declining land values. With growing population we may 
have a fall in the value of agricultural land. The general prin- 
ciple is clear and may be stated as follows: In a dynamic society 
we learn how to utilize better and better the surface of the 
earth. Consequently, with a stationary population land values 
will decline. The force acting in the other direction is the growth 
of population. In recent years particularly in the United States, 
although it is also true in many other countries, improved methods