3s8 SECTIONAL TRANSACTIONS.— C. 



works. Since the region is one of low relief, storage of water in reservoirs 

 plays an insignificant part. The River Trfent supplies some of the needs 

 of neighbouring industrial concerns and is a waterway of much value. 

 A huge reserve of water for human consumption is preserved in the Bunter 

 Sandstone and is the chief source of supply for Nottingham and many other 

 towns and a much larger number of villages. The Lincolnshire Limestone 

 holds a large volume of water which unfortunately fluctuates greatly with 

 the seasons. The Spilsby Sandstone is proving a valuable reservoir for 

 East Lincolnshire. The chief building stones of the area are provided by 

 the Magnesian Limestone north of Mansfield and the Lincolnshire Lime- 

 stone at Lincoln and near Ancaster. The latter is also extensively used in 

 making foundations for roads. The Keuper Marl near Nottingham and 

 the Lias clays at Lincoln and Grantham supply material for brick making. 

 The floor of the Trent valley and the terraces on either side provide vast 

 stores of gravel for concrete and for road surfaces. A narrow belt of 

 country running north and south through the area provides hydraulic 

 limestones for making cement and gypsum for making plasters. The 

 Lincolnshire wolds also contain extensive beds of cretaceous iron ore. 



Mr. S. G. Clift. 



The exploitation of the Nottinghamshire Concealed Coalfield only dates 

 back to 1859 when the Shireoaks Colliery struck the Top Hard seam at 

 a depth of 1,500 ft. beneath the Permian limestone. The progressive 

 easterly movement of collieries has made two facts clear, the one that the 

 cover of newer rocks increases eastwards at a rate of 100 ft. to the mile, the 

 other that the folds and faults of the visible field continue undiminished 

 under that cover. 



The normal easterly dip of the seams soon gives place to a pronounced 

 rise and what was thought to mark the eastern rim of the field has proved 

 to be but one of those concealed folds. A borehole to the east of the River 

 Trent has proved the existence of valuable reserves of coal beneath Lincoln- 

 shire. Though the eastern limit is conjectural, the limit of exploitation 

 under modern conditions cannot extend much beyond Lincoln where the 

 overburden of newer rocks reaches 3,000 ft. 



The coals of Nottinghamshire are primarily house and industrial fuels 

 of low- ash content and free burning qualities. The lower seams of the 

 Middle Measures maintain their thickness eastwards and must form a vast 

 potential reserve. The thinning of the Coal Measures in a S.E. direction 

 does not affect the coal seams to the same extent. 



The field is an original basin of sedimentation with the basin-like character 

 accentuated by pre-Permian movements. 



Advances in the technique of sinking have made possible the exploitation 

 of Coal Measures lying beneath heavily watered strata, but the effects of 

 colliery subsidence on water undertakings situated on the Bunter Sandstone 

 are being watched with anxiety. 



Dr. D. A. Wray. 



Recent investigations made on the cores obtained from deep borings 

 on the borders of Lincolnshire appear to have an important bearing on 

 the probable easterly extension of the East Pennine coalfield. Two borings 

 carried out not far from the Trent and ten miles to the north of Gains- 

 borough revealed some 1,700 ft. of Coal Measures underlying 1,500 ft. of 

 Permian and newer rocks. From the evidence of the non-marine lamelli- 

 branch found, all the productive Coal Measures were represented, but in 



