Ten years ago two pairs of Romano-British kilns for the manufacture of pottery were discovered by some boys from Bootham School, York, on the slope of the hill from Whitwell to the Crambeck, about thirteen miles north-east of York and five miles from the fortress of Malton. These were excavated by boys from Bootham School under the writer's supervision, and details of their structure and of the pottery made in them have been published. Earlier finds of kilns in the same neighbourhood were then recorded, and these, together with the amount of pottery recovered, made it clear that pottery manufacture had been very extensive in the district. Since that report was published, the importance of Crambeck wares and their wide distribution in the northern military area in the fourth century have been widely recognized. The discovery of another pair of kilns in 1936, which throw more light on kiln-structure than did those of the earlier find, provides, in the light of subsequent investigations, an opportunity for a fuller discussion of the date of their activity than was at that time possible.