2 BULLETIN 696, U. S. DEPARTMENT OF AGRICULTURE. 
for instance, occur in areas wherein relatively high prices prevail 
for corn. In the South lower production, higher prices, and smaller 
consumption of wheat and other cereals go hand in hand. 
Such price differences are not accidental; they are traceable to 
fundamental conditions which in many instances are contrary to 
the general tendencies. Particularly is this true in the producers' 
price, or " farm price," which is the basic as well as the first and 
lowest price of food products. 
The present investigation is confined chiefly to the influence of 
producing areas, trade routes, and consuming centers upon prices 
paid to farmers for corn and to a survey of the regional differences 
in such prices. 
Existing types of agriculture are determined by a combination of 
physical and commercial factors. Physical limitations upon most 
agricultural products may be said to be measured by the average 
yield in bushels to the acre. High or low yields per acre decrease or 
increase costs of production. It is also apparent that commercial 
limitations on production are to a large degree reflected in the price 
obtained by the farmer. 
When the varying farm prices of a product are properly charted on 
a map they are seen to increase or decrease in determinate directions. 
The regions of lowest and of highest prices are thus shown clearly, 
also regions or zones of intermediate prices. The directions of the 
price movement vary with each product. Small areas appear where 
farm prices are higher or lower than in the surrounding territory 
or zone. 
The " geography of farm prices " is thus a controlling element in 
crop selection. Climate and soil are, of course, the dominating 
physical factors which determine local types of agriculture. But 
the local farm price is an index of commercial conditions that are 
hardly less important. Given a sufficiently high price, obviously 
products could be grown profitably under unfavorable physical con- 
ditions. 
DATA EMPLOYED AND METHOD OF TREATMENT. 
" Isotimes." the term used for lines bounding areas of like price. 
Counties as basis of measurement, and a five-year average employed to 
distinguish normal from spasmodic price differences. 
To the lines delimiting areas of like price the term "isotimes" 
(price lines) has been given, 1 similar to "isotherms" and "isobars" 
as applied to lines running through points of like temperature or 
barometric pressure. Just as the course of climatic changes is out- 
lined in the latter two so are local or general commercial disturbances 
reflected in the isotimes. 
i Th. H. Engelbrecht. 
