20 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [NOV. 5, 



state of the ground being favourable to such an interpretation, and 

 the nature of the deposit itself likewise tending to strengthen that 

 belief. 



The deposit when first brought up is soft, damp, clammy to the 

 touch, of a dark colour* and nauseous smell, and is capable of 

 being cut through with a knife. Even after remaining at the mouth 

 of the shaft of the Water-way (No. 11) four years, the part of it 

 partially covered with other material retained its soft, moist con- 

 dition. Kept dry for a time, it assumes a much lighter, greyish 

 appearance. 



Tarns. — The Tarns, or small lakes, laid down on the Ordnance- 

 map are not wholly unworthy of notice. " Standing Tarn," a small 

 sheet of water, situated about a mile to the south-west of Lindale, 

 has no surface -inlet or -outlet ; but it has a very open subterranean 

 outlet, which is stemmed by the farmers with straw and mud. 



A Tarn about two miles south of Lindale, called " Longlands 

 Tarn," has also a wide aperture of escape leading underground; 

 chaff thrown in there has been detected in the Stainton-mines, three- 

 quarters of a mile distant. Such an experiment would prove that 

 there is an open passage throughout the distance, and this I believe 

 to be the general character of the ground ; water seldom infiltrates, 

 but courses uninterruptedly on its way. Thus, water pumped into 

 a " Swallow-hole " near the Stainton-mines flowed unfiltrated to 

 Gleaston-mill, a mile further south. Almost all the mines are 

 troubled with water — not merely top-water, but ' under- water,' 

 rushing along at great depths, over which the engines seem to 

 have little power. 



Cavernous nature of the ground. — The facts above stated will be 

 no matter for surprise, when the cavernous state of the ground is 

 taken into consideration. 



The caverns occur in the earth or Drift overlying the Mountain- 

 limestone f. On an accompanying Map (fig. 1), traced from the 

 Ordnance-sheets Nos. 11 and 16, the situations of the respective 

 caverns are attempted to be shown. 



One marked about a quarter of a mile to the south-east of the 

 Lindale Railway-station was disclosed by the surface giving way 

 under the plough, and letting in the horses ; this was about 12 feet 

 deep. 



Another smaller cavern is situated close behind the station. This 

 one I have visited ; like the last, it is close to the surface, and was 

 met with in making a new occupation-road. It was, when discovered, 

 two or three yards broad ; it is now a good deal filled up, but close 

 to a fence under which it seems to pass, an opening is left. I col- 

 lected some of the material forming its roof and sides, specimens of 

 which are in the Society's Museum. 



* Some lately found and brought to me while yet moist could scarcely be 

 distinguished from bog-peat, and it burned like peat-fuel. 



f For calling my attention to these interesting caverns, and for the informa- 

 tion connected with them, I am chiefly indebted to Mr. Lawn, of Ulverston. 

 mining-agent of the Earl of Derby. 



