189 



EVIDENCES OF GLACIAL ACTION 

 NEAR INGLETON. 



ROBERT R. BALDERSTON, 

 Ingle ton. 



The evidences of glacial action, as indicated by drift-formation, are 

 very considerably manifested in the neighbourhood of Ingleton, in 

 the valleys of the Greta, Twiss, and Doe. Ingleton itself stands on 

 Drift 70 feet thick, whilst on the opposite side of the river, in Enter 

 or Tenter Banks, the accumulation is at least 140 feet from top to 

 bottom. This deposit consists of boulders 6 feet and less in diameter, 

 for the most part derived from formations seen in the neighbouring 

 hills, or from others situated elsewhere, but presenting a similar 

 character. These boulders, when in situ, are found lodged indiscrim- 

 inately in earth varying to some extent in character, according to the 

 locality examined. In certain places — as, for instance, the neighbour- 

 hood of the church — there is a preponderance of sand and gravel as 

 compared with clay ; in others, the latter substance is more inclined 

 to predominate. In the cutting between the Cemetery and Yarlsber, 

 a good section of the lighter and finer description of Drift was 

 recently exposed; in some places there were pockets or local deposits 

 of sand, a little of a light colour, but the greater part of very dark 

 hue, and mixed with small pebbles of quartz, spar, and other sub- 

 stances ; few boulders of material size were to be seen, whilst the 

 constituents of the gravel element, where this was predominant, were 

 small in size, and not approaching the nature of shingle. The 

 general situations in which the constitution of the Drift is most satis- 

 factorily examined are the river's bed or the banks immediately 

 adjacent, the streams having cut their way between slopes of Drift 

 towering above to the height of 100 feet to 150 feet, whence they 

 have rolled or gradually been dislodged by the undermining action of 

 water, so as to collect below, conveniently for the geologist's inspection. 

 The description of boulders prmcipally observed are: (i) Sandstones 

 from the Yoredale Millstone Grit series ; (2) Black Marble occa- 

 sionally from the Yoredales; (3) Productus Limestone from the same 

 series ; (4) Crinoidal Limestone from the upper portion of the last- 

 named formation ; (5) Mountain Limestone, upper and lower ; 

 (6) Blocks and boulders from the grainless, non-fissile, Lower 

 Llandeilo beds, locally known as 'Calliard'; (7) Numerous examples 

 of the coarse-grained, derivative, green porphyry, found in situ in 

 patches — not dykes or beds — at a point two miles distant from 

 Ingleton, on the S.E. side of the Doe; finer-grained examples of 



July 1888. N 



