244 W. H. Hudleston — Creechharrow in Piirbeck. 



This diagram, wbicli has an horizontal extension of about 8 miles 

 from south to north, is intended to represent the general topographical 

 and geological structure of the Trough of Wareham on a meridian 

 both east and west of Creechbarrow. The section itself may be 

 tak6n more particularly to repi'esent a meridional line to the 

 westward of that hill drawn through West Creech, Binnegai", and 

 Bere Heath. Accurate detail is not attempted, but the thoroughly 

 exceptional character of Creechbarrow can be gathered from the 

 dotted outline of the hill itself, projected on the section. We 

 perceive at a glance that the Tertiary beds in this hill are just 

 twice as high above sea-level as they are in the normal or general 

 section between the Purbeck Hill and the Frome Eiver. The latter 

 is the northern boundary of the Isle of Purbeck.^ 



Having thus impressed upon the meeting the thoroughly ex- 

 ceptional character of Creechbarrow in its relation to the rest of 

 the Tertiary beds in the neighbourhood, I next endeavoured to 

 adduce some reasons for the explanation of this anomaly. Premising 

 that hills, as we see them now, ai-e the outcome of certain elevating 

 forces of a remote period, and that they have been fashioned by 

 meteoric agencies, which themselves are modified by various internal 

 and external peculiarities, I ofi'ered three possible suggestions or 

 theories to account for the existence of Creechbarrow as we now 

 see it, and for its exceptional relation to the Bagshot Beds of the 

 immediate district, which largely consist of potter's clays of different 

 qualities (the Pipeclay beds). 



(1) The first of these suggested explanations may be summed up 

 under the heading " Exceptional development of the Creechbarrow 

 Beds themselves." It is well known what valuable workings in 

 the clays at the foot of the Purbeck Hill have been carried on 

 for nearly a century. This has been one of the most important 

 industries of East Dorset. We may trace the line of the old 

 workings exactly as if drawn on a map all the way to Corfe Castle. 

 An old workman who had long been engaged on this business 

 pointed out to me some time ago that Creechharrow bulges all these 

 beds and throws them out of line. Such a state of things tends to 

 prove that there is something peculiar in the original composition 

 of this monticle. It may be inferred also from the above statement 

 that the Creechbarrow Beds contain no potter's clay. An inspection 

 of the map showing the curve of these workings will prove at once 

 how correct was the old workman's remark about the bulging of the 

 Pipeclay series.^ So much for theory No. 1. 



(2) The second explanation, or rather suggestion, had reference 

 to the proximity of the great thrust-plane which governs the 

 tectonic constitution of so much of the Isle of Purbeck. "It is 



^ The general structure of the Trough of Wareham is uo doubt that of an unclu- 

 latino- syncline, hut owing to the softness of the Bagshot Beds accurate stratigraphy- 

 is not attainable. I am inclined to believe that the original bottom of the syncline 

 is represented by the Plateau -gravel on Binnegar Plain, and that both the Frome and 

 Puddle Valleys have been excavated subsequeutly. 



2 Map to accompany the forthcoming paper iu the Proc. Dorset Field Club. 



