Effect of Climate and Soil upon Agriculture 23 
(g) Organized commerce falls to the level of barter in regions 
where people are scattered and productive labor runs low. 
(1) Highly organized government exists in regions where labor 
is much divided and people become interdependent. 
Without the aid of ideas and material from a number of sources the 
presentation of matter in this article would scarcely have been possible. 
I am pleased therefore to make acknowledgment to the following: 
Prof. H. F. Williams, Farm Management Extension; Prof. G. A. Love- 
land, Meteorology; Dr. G. E. Condra, Geography and Soils; Dr. R. J. 
Pool, Botany; Prof. E. Hopt, Field Crops; Dr. G. O. Virtue, Political 
Economy and Commerce. 
