In the valuable chartulary of the abbey of Burton-on-Trent, preserved at Beaudesert, there are full accounts of the tenantry on their Staffordshire and Derbyshire manors drawn up about the year 1100, as well as some like entries of the year 1114. It would be very difficult to find such easy tenures on any secular manors of approximate date. In a variety of cases a house was held for which a single day’s harvest work per week for the lord was the only charge. The proportion of _ad opus_ tenants on these estates was unusually small; thus at Mickleover, out of a total of seventy-eight only twenty-two had to make any return in labour, and in each of these cases the villein held two bovates or oxgangs of land in return for two days’ labour a week at harvest-time, the occasional carrying of a load to the lord’s garden, and ploughing once in the winter and twice in the spring. Their position, too, is also shown by the fact that they were cowkeepers; for time was allowed them, when working for the lord, to drive home and milk their cows, and generally to attend to their stock. In two other Mickleover cases _ad opus_ tenures of two bovates of land had recently (1100) been commuted by the abbot for 2_s._ a year, a sum which gives a good idea of the comparatively small amount of exacted labour. In the adjoining township of Littleover there were twenty-two villeins, including Goderic the reeve, the majority of whom held two bovates of land; but in only four cases did they make recompense to the lord by labour. On the same manor there were, in 1114, five men in charge of the plough oxen (_bovarii_); each of them held one bovate of land and two acres of marsh in return for making or providing the irons of three ploughs, the amount of demesne land being sufficient for three ploughs. On another of the abbot’s Derbyshire manors, Willington, there was no “inland” or demesne land, but there were thirty-two bovates, seven of which, sufficient for two ploughs, were held by the lord. The remaining twenty-five bovates were thus held:--One, with part of the church meadow, by Goderic the priest; Unifred, six bovates for 6_s._; Soen, four bovates for 6_s._; Serlo, two bovates for 2_s._; Lewin, the reeve, one bovate for 1_s._; Hotin, one bovate for 2_s._; Godwin, half bovate for 11_d._; Lewric and Lewin, each two bovates for 32_d._ and two days’ work a week from July to Martinmas; Edwin and three others, each one bovate for 16_d._ and two days’ work for the like period; Godric, half bovate for 8_d._ and half day’s work for the like period; and Lewin, the smith, one bovate by the service of two ploughs, or for 16_d._ and work as above.