2 BULLETIN 748, U. S. DEPARTMENT OF AGRICULTURE. 
The hours of man labor and horse labor do not vary greatly from 
ene period to another. Moreover, the quantity of seed planted per 
acre will not change perceptibly throughout a given period, and the 
applications of manure or fertilizer are not likely to increase or 
MENOMINEE 
: 
GENESEE |LAPEER 
Ap, 
ASSO 
OAKLAN, 
sag 
INDIAN A 
@ Location of factories operating 19/4-/9/5 e Location of idle factor/es 
8 Location ofarea stvdied 
Fig. 1.—Map showing the districts in which records were obtained, also indicating 
the location of the beet-sugar factories in Michigan and Ohio. 
decrease to any marked extent. Other necessary supplies will remain 
fairly constant. In presenting accompanying tables these facts have 
been kept in view, so that if the reader wishes to figure the cost of 
production on the basis of prices other than those prevailing when 
