the additional number (if any) that might be employed; then the river-meadows, woodland, pasture, fisheries (i.e. fishing weirs), water-mills, salt-pans (if by the sea), and other subsidiary sources of revenue; the peasants are enumerated in their several classes; and finally the annual value of the whole, past and present, is roughly estimated. The organisation of the returns on a feudal basis, enabled the Conqueror and his officers to see the extent of a baron's possessions; and it also showed to what extent he had under-tenants and the identities of the under-tenants. This was of great importance to William, not only for military reasons but also because of his resolve to command the personal loyalty of the under-tenants (though the "men" of their lords) by making them swear allegiance to him. As Domesday Book normally records only the Christian name of an under-tenant, it is not possible to search for the surnames of families claiming a Norman origin. Scholars, however, have worked to identify the under-tenants, most of whom have foreign Christian names. The survey provided the King with information on potential sources of funds when he needed to raise money. It includes sources of income but not expenses, such as castles, unless they needed to be included to explain discrepancies between pre-and post-Conquest holdings of individuals. Typically, this happened in a town, where separately-recorded properties had been demolished to make way for a castle. Early British authors thought that the motivation behind the Survey was to put into William's power the lands, so that all private property in land came only from the grant of King William, by lawful forfeiture. The use of the word antecessor in the Domesday Book is used for the former holders of the lands under Edward, and who had been dispossessed by their new owners. Subsequent history Custodial history Domesday Book was preserved from the late 11th to the beginning of the 13th centuries in the royal Treasury at Winchester (the Norman kings' capital). It was often referred to as the "Book" or "Roll" of Winchester. When the Treasury moved to the Palace of Westminster, probably under King John, the book went with it. The two volumes (Great Domesday and Little Domesday) remained in Westminster, save for temporary releases, until the 19th century. They were held originally in various offices of the Exchequer: the Chapel of the Pyx of Westminster Abbey; the Treasury of Receipts;