INK TIMASSir SYSTKM ."'''.1 



i>r the Geological Survey, though it was described a> IVimian in 

 tlit- "Summaries of Progress" for 1896 and 1898. These lower 

 beds are about 1000 feet thick, and consist of bright-red sandstones 

 with conspicuous current bedding, thus re>eml>ling tin- Penrith 

 Beds ratlu-r than the St. Bees' sandstone. They are overlain and 

 overlapped by conglomerates, which are probably of Triassic age, 

 though they seem to follow in conformable succession. 



3. South-Western Area 



In this district there is nothing comparable with the Lower 

 Mottled sandstone of the Midlands, and in the typical section of 

 the. south coast of Devon, near Budleigh Salterton, the Bunter is 

 less than 500 feet thick. It is composed of the following bed- : - 



2. Coarse red sandstones . . . from 350 to 400 feet. 

 1. The Pebble Bed or conglomerate . about 80 feet. 



The Pebble Bed rests directly on the red Permian marls 

 mentioned on p. 333, but without any sign of erosion, for the lowest 

 pebbles are embedded in a sandy clay which is continuous with the 

 marl below. The mass of the Pebble Bed consists of well-rounded 

 oval pebbles of quartzite and hard grit embedded in a matrix of 

 red sand ; it exhibits current bedding and includes lenticular layers 

 of sand. Some of the pebbles contain Devonian fossils, and others 

 are Silurian and Ordovician, resembling the Gres armoricain and 

 the Gres du May of Brittany and the Ordovician rocks of Cornwall. 

 Dark, compact, tourmaline rocks also occvir, like some which occur 

 in the metamorphosed /ones round the granite masses of Devon 

 and Cornwall. 



According to Professor Bonney, however, the majority of tin- 

 pebbles do not resemble Devon and Cornwall rocks, while there 

 are some of a hard red quartz-felspar grit which resembles the 

 Torridon sandstone of Scotland, but is equally like some parts of the 

 Gres felspathique at the base of the Ordovician in Normandy. It 

 is, in fact, now generally conceded that this assemblage of pebbles 

 was brought by'a river or rivers from the south, i.e. from Normandy 

 and from land which then occupied the southern part of the 

 English Channel. Oval quartzite and quartz-grit pebbles have, in 

 fact, been dredged from the floor of the Channel at many points 

 from 15 to 50 miles south of the Eddystone. 



This conglomerate can be traced inland through Devonshire 

 into Somerset, but the pebbles become smaller in that direction, 

 and the quartzites becomes less and less abundant, till at Burlescoml >< 

 the bed passes into a sandy gravel composed chiefly of small quart/ 

 and grit pebbles. 4 



