The plates facing pages 385 and 452 of this number represent the culminating point of archaeological air-photography. They were taken by Pilot Officer Jonas, R.A.F., between I I and 12 o'clock on the 16th of May 1929, using a K.Z filter. The sites lie half a mile apart on the hill called Woodbury, less than a mile south of Salisbury Cathedral, between the Blandford and Bournemouth roads. Woodbury is three miles south of the aerodrome at Old Sarum, from which they were taken and where I found them when taking over obsolete negatives on behalf of the Ordnance Survey (where they now are). They were taken during pin-pointing, as part of the ordinary routine of training; but that these particular sites were selected for practice is due to the keenness of the photographic section at Old Sarum, which has been closely associated with the development of this branch of air-photography from its birth. (It was the Old Sarum section that obtained many of the first archaeological air-photographs ever taken, including those of the Stonehenge Avenue, in 1921, and of the Celtic fields round Winchester, in 1922). Regarded merely photographs, from a technical standpoint the negatives are as nearly perfect as possible. The wonderful definition of the crop-marks is probably due partly to the use of a K.2 filter, partly to the dry spell during the first half of 1929.