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 excellent work, It is a great thing to walk much, to get a thorough geographical idea of the tract of country you ave about to examine. Suppose at the meeting of your "committee on the drift deposits" you with a friend have undertaken the examination of a district including, say ten square miles. Then the best thing to do is to learn this little region thoroughly, to master the course of every brook and streamlet, the position of every house and hedgerow. The number of new facts that are sure to turn up will surprise you.

A complete list of what has already been written upon the drift would more than fill one number of this magazine. "The Great Ice Age," by Mr. Jas. Geikie, (2nd edition, 24s., Daldy, Isbister, and Co.,) is an excellent book. Mr. Searles V. Wood, jun., is another high authority on the subject, to whom I am personally indebted for much kind advice. Unfortunately Mr. Wood's papers are chiefly in the "Journal of the Geological Society" or in the "Geological Magazine," but if may safely be said that no one has done more remarkable and original work in connection with the glacial deposits (chiefly of the eastern counties) than Mr. Wood, In "Geological Survey Memoirs," lately published by Mr. de Rance ("Superficial Geology of S.-W. Lancashire," 17s.) and by Mr. S. B. J. Skertchley (the "Fen-Land," 40s.) we get, of course, most reliable and interesting information, but the price of these works is to individuals almost prohibitory. Such works, however, may well be aided to the libraries of all our societies. I will endeavour to review these two books in our next (October) number. In H. B. Woodward's "Geology of England and Wales" (Longmans, 14s.) there is also a good and full resumé.

No very special training is needed on the part of those who are willing to lend a helping hand. For instance, we want to know how far the chalky boulder clay of the eastern counties extends to the west and south, and also the relations to it of certain beds of flinty gravel and sand. Now everybody knows the appearances of a lump of chalk and a piece of flint, and we ought to be able to fix the westward extension of these beds to a certainty. I have never seen the clay full of bits of chalk in size from a pin's head upwards, at any point west of Charnwood Forest, but then I have not enjoyed many opportunities of examining the drift of Staffordshire, Warwickshire, &c. The flinty gravel appears to stretch further west, but what is its limit in this direction? Again, in the midland district we hold the key to the correlation of the deposits of the cast and west coasts. It is now thought that the glacial deposits of Lancashire and Cheshire are of a later date than the "mid-glacial sands" and chalky clays of the east coast. We must endeavour to track each set of deposits as far inland as possible, and observe their relative behaviour.

With this branch of geological study is bound up the question of the origin of man. If in the Victoria Cave, near Settle, clear evidence is obtainable of pre-glacial or inter-glacial man, why should not other evidence of his presence in the centre and north of England be found?