Against this general explanation of the enclosure movement, it is urged, first, that the withdrawal of land from cultivation began long before the date at which the enclosure movement, caused by an alleged rise in the price of wool, is ordinarily said to have begun. The fourteenth century was marked by agrarian readjustments which have a direct relation to the enclosure movement, and which cannot be explained by the Black Death or the price of wool. Even in the thirteenth century the causes leading to the enclosure movement were well marked. Secondly, the cause of the substitution of sheep-farming for agriculture in the fifteenth and sixteenth centuries cannot have been a rise in the price of wool relatively to that of grain, because statistics show that the price of wool fell during the fifteenth century, and failed to rise as rapidly as that of wheat in the sixteenth century. Thirdly, a mere comparison of the relative prices of grazing and agricultural products cannot explain the fact that conversion of open-field land to pasture continued throughout the seventeenth century in spite of prices which made it profitable for landowners at the same time to convert a large amount of grass-land to tillage, including enclosures which had formerly been taken from the common fields. If these facts are accepted the explanation of the enclosure movement which is based upon a comparison of the prices of wheat and wool must be rejected, and the story must be told from a different point of view.