PROCEEDINGS OF THE COTTESWOLD CI.UB 6\ 



of this water passes into the Thames, being lost by under- 

 ground drainage in a south-easterly direction. A curved 

 line drawn from Trinity Mill, commencing two miles above 

 Cirencester, through Barnsley Park to Bibury, thence north 

 to Aldsworth, Sherborne Lodge, Windrush Camp, Little 

 Barrmgton and Burford, will probably determine the 

 southern Hmit to the Fuller's Earth within the Thames 

 watershed, between the extreme points at Trinity Mill, 

 above Cirencester, and Burford ; south of this line I 

 believe most, if not all, the spring water is lost to the 

 Thames. 



On its way south, over the Upper Lias, as far as 

 Withington, the Coin receives springs from Brockhampton, 

 Sevenhampton, and the fine springs of Syreford, frequently 

 yielding from three to four million gallons per day. For 

 six miles from its source the Coin flows over the Upper 

 Lias Clay to Withington, draining the sands above, and the 

 extremely flmlted Inferior Oolite receiving feeders from the 

 springs of Andoversford, Frog Mill, and Withington, it then 

 occupies the Inferior Oolite as far as Foss Bridge and 

 Coin St Dennis. From Foss Bridge to Coin Rogers, 

 Winson, Ablington, and the great spring at Bibury, the 

 river flows through the deep valley in the Great OoHte 

 and Forest Marble, which is denuded down to the 

 retentive clays of the Fuller's Earth, over which the 

 Churn runs. 



From Bibury to Coin St Albans, Hatherop, and Quen- 

 ington, and as far as Fairford the Fuller's Earth is lost at 

 the surface, nevertheless it influences the water system 

 as far as Fairford, where all springs cease. 



From Fairford to Lechlade the Coin occupies the 

 argillaceous plain of the Oxford Clay, and enters the 

 Thames close to the Round House, at the junction of the 

 Thames and Severn Canal, one mile west of Lechlade. 



The Coin in its course drains an area of 70^ square 

 miles from the following eight Jurassic Rocks : 



