Professor P. F. Kendall — The English Eskers. 101 



sections exposed in the construction of the great railway station 

 at York : he has very generously placed all his notebooks in my 

 hands. 



The Memoir of the Geological Survey, published in 1881, described 

 the ridges, and gave excellent diagrams exhibiting their structure 

 but significantly refrained from speculation on the subject of their 

 mode of origin, which was said to be part of a very large subject 

 and not to be discussed in a local memoir. My own contribution 

 appeared in 1894 (not 1893 as stated by Professor Gregory). Fox 

 Strangways ^ in 1895 added many details and supported the morainic 

 theory, which he applied also to other areas of Yorkshire. 



Except brief summaries by myself in the Victoria History of 

 Yorkshire and the Handlmch der Regionalen Geologic, the only 

 addition to the knowledge of these ridges prior to Professor Gregory's 

 is the brief allusion to them by Professor Bonney in his Presidential 

 Address to the British Association, a few isolated observations iipon 

 a borehole at Escrick, and references to the laminated mud overlying 

 the mounds near York. 



Let us now see what Professor Gregory has to say. " Two 

 curved bands of glacial sands and gravels occur in this part of 

 Yorkshire. ... A second curved band of boulder clay capped by 

 sand and gravel is marked on the Geol. Surv. Map (Sh. 93 S.E.), 

 passing 5 miles south of York through Catton to Escrick and 

 Stillingfleet (35 feet)." It is difficult to attach any other meaning 

 to the figures " 35 feet " than that this is the height of the ridge 

 above Ordnance Datum. In fact, the village does not stand on the 

 ridge, which here ranges from 85*9 down to 50 feet, where it is 

 truncated by the valley of the River Ouse, but at one intermediate 

 point it falls to 48 feet. Professor Gregory's figures are grossly 

 misleading. 



Of the southern ridge Professor Gregory remarks " Its height is 

 about 30 feet above the adjacent plain ; its slopes are gentle, and 

 it shows neither the humpiness characteristic of moraines, nor the 

 steep sides of kames. I saw on it no large erratics. It appears 

 to be a rise left by denudation. This view agrees with that of 

 Professor Bonney . . . ' the so-called moraines near York . . . 

 do not, in my opinion., show any important difference from ordinary 

 hills of sands and gravels, and their materials are wholly ixnlike 

 those of indubitable moraines that I have either seen or studied 

 in photographs.' " 



Before coming to any decision regarding these remarkable ridges 

 one would have expected a geologist to make himself familiar with 

 their form, constitution, and relation to the adjacent deposits, 

 especially as he comments on the fact that the published information 

 deals " rather with the distribution of the drifts than with their 

 composition and structure ". To supply the omission Professor 



^ Proc. Y. G. and P. Soc, vol. xiii, p. 18 et seq. 



