72 ENGLISH FIELD SYSTEMS 



two-field and three-field modes of tillage reduces, in short, to the 

 utilization of an additional one-sixth of the arable each year. 

 The resort to fallowing, the equitable apportionment of strips to 

 fields, the pasturage arrangements — all the essential features of 

 the system — remained unchanged. A divergence so slight is 

 scarcely one which would evince tribal or racial peculiarities. 

 It would indicate, rather, differing agricultural opportunities as 

 interpreted by men whose fundamental ideas about agriculture 

 were the same. This consideration leads to the inquiry whether 

 the simpler two-field tillage gave place, as civilization advanced, 

 to the somewhat more elaborate three-field one. 



As there was little difference in size between the areas within 

 which two-field and three-field husbandry prevailed in the thir- 

 teenth century, so the extant evidence does not clearly indicate 

 priority of one over the other in point of time. Of the situa- 

 tion before the feet of fines begin at the end of the twelfth cen- ' 

 tury we know little. Although one or two Anglo-Saxon charters 

 seem to refer to two fields, they constitute no ground for a general- 

 ization. Certain inferences, however, are possible in this con- 

 nection. If we admit that a two-field arrangement was simpler 

 than a three-field one, and discover that at a later time town- 

 ships sometimes exchanged the former for the latter, we shall not 

 be unready to believe that the three fields which were existent 

 by 1 200 may themselves have been the outcome of a similar trans- 

 formation. Were this the case, the original system of the English 

 midlands should be looked upon as one of two common arable 

 fields. For this reason the occurrence of the transformation at a 

 later time becomes a point of importance. 



Two- and three-field arrangements did not, as we have just 

 seen, correspond with tribal usages, but simply with agricultural 

 opportunity. Hence a change from one to the other was a 

 matter of opportunism. As demands upon the soil increased, 

 and as it was observed that the three-field system brought under 

 tillage one-sixth more of the arable each year than did the two- 

 field system, the question must have arisen whether it would pay 

 to change a township's arable fields from two to three. It might, 

 of course, have been argued that in the long run a two-field 



