226 REPORT— 1902. 



clay, so that it was impossible to obtain any definite evidence regarding 

 the thickness of the bed. 



Further, although boulder clay was proved to underlie the alluvium 

 on both banks of the Ribble, it was impossible to obtain evidence of its 

 existence in the river-bed, as this consists of coarse shingle which could 

 Iiot be penetrated by the hand-boring apparatus. 



In order to clear up this matter satisfactorily it will be necessary to 

 engage the services of a professional well-sinker and to have one or two 

 boreholes put down by mechanical meana» 



Investigation of the Streams tributary to, or in the neighbourhood of, 



Alum Pot. 



A series of small springs rises beneath the drift and peat near the 

 wall at the north end of Whit-a-Green : these run together and form a 

 small stream which sinks at P 34, a small pot-hole amongst long grass. 

 Fluorescein was introduced here and reappeared in half an hour at a 

 small opening some hundred yards to the south of P 34 : here the 

 stream can be traced on the surface for 20 yards, when it again 

 sinks. 



The fluorescein was put into P 34 at 4 p.m., and was traced the 

 following day at S 52 ; then overground to P 35, where it again sank 

 to reappear at S 49 ; thence it flowed to P 36, and so underground to 

 S 50, finally sinking at P41. 



The fluorescein sinking at P 41 did not afiect any of the springs on 

 Font Green, but was again seen in Footnaw's Hole. 



This water must therefore go by a deep course, and eventually join the 

 underground flow from Alum Pot to Turn Dub, vid Footnaw's Hole. 



Whit-a-Green Spring. — This rises on the higher slopes of Simon Fell 

 at a height of 1,600 feet, and flows over the surface of the rocks of the 

 Yoredale Series till it reaches the underlying Carboniferous limestone at 

 1,250 feet, where it sinks at P 29. 



A trial with fluorescein resulted in proving that this water flows out 

 at S 55 and falls into the middle opening of Long Churn, known as Dickon 

 Pot, P 30, where it joins the main stream occupying that channel. 



The channel by which this stream flows can be traced for a consider- 

 able distance by means of a series of openings to the surface, and it was 

 found to be possible to actually traverse the tunnel throughout almost 

 its entire length ; but the exploring party was eventually stopped by the 

 roof coming down to the water level. 



Small Spring to the North-east of last (S 53). — There is never much 

 water in this spring, and it is quite dry in seasons of drought. It 

 probably derives its water from the peat at its head. 



The water sinks at P 28 and issues, as proved by a fluorescein test, 

 at S 55, along with the water from P 29, 



The undergroutid junction of these two streams was afterwai'ds 

 ti-aced, though it was found to be impossible to follow the whole length 

 of the passage, the roof being too low, and there being deep pools of wa,ter 

 lying in the bottom. 



It may be mentioned in passing that as this was a short run methy- 

 lene blue was tried for the test, but although only a small quantity of 

 water was flowing at the time it was not seen at S 55 ; one-fourth 

 the quantity of fluorescein, however, succeeded two hours later. 



