PROCEEDINGS OF THE COTTESWOLD CLUB 75 



on its western side from the basin of the Upper 

 Thames, and Swill Brook, by its water system draining 

 in a different direction to that of the Churn, the Ampneys, 

 and Coin, or from south to north ; the waters of the 

 Dance, Ray, Cole, and Highworth Streams flowing from 

 the Cretaceous, Kimmeridge Clay, and Corallian Rocks of 

 Swindon and Highworth on the south, over the Oxford 

 Clay to Cricklade and Lechlade. 



This broad Basin is drained chiefly by the Ray and 

 Cole, both of which rise in the Chalk, and receive their 

 waters through numerous tributaries flowing from the 

 Chalk and Upper Greensand escarpment of Chisledon, 

 Liddington, and Bishopstone, and over the broad plain 

 of the Gault and Kimmeridge Clay to the Thames. 



Basin of the (Swindon) Ray 



The Ray rises in the Upper Greensand at Wroughton, 

 a western branch uniting at North Lanes, a third to the 

 west at Elbro Bridge and Haydon, where the main stream 

 passes to and enters the Thames near Water Eaton 

 House, east of Cricklade. 



The supply of water during heavy rainfall is large, 

 rapidly draining the surfaces of the Impervious Oxford 

 and Kimmeridge Clays which occupy the chief area of the 

 basin. 



The Ray drains 36)^ square miles from six divisions 

 of the Jurassic Rocks, but chiefly from the Oxford Clay, 

 Coral Rag, and Kimmeridge Clay, and from the Cretaceous 

 escarpment along the southern divide of the basin ; its 

 direct course to the Thames is between eight and nine 

 miles, one half being over the Oxford Clay ; neither the 

 Kimmeridge or Oxford Clays yielding any springs. 



The diversity of the strata comprising the structure of 

 the drainage area of the Ray may be gathered from the 

 following table : 



