282 



NATURE 



[October 28, 1920 



The Floor of Anglesey.' 

 By Prof. Grenville A. J. Cole, F.R.S. 



THE thoughts of travellers across Anglesey in 

 the Irish mail-train are usually controlled 

 by a previous vision of the breakers rolling in on 

 Colwyn Bay ; yet many must have been attracted 

 by glimpses of grey homesteads set on elongated 

 mounds, farmlands alternating with strips of marsh 

 and moor, and here and there the "desert 

 scenery " of some sunlit groove, bounded by low 

 terraces of ancient rock, along which the sand 

 has drifted inwards from the sea. In 1895 Mr. 



of research ; but nothing in Anglesey proved 

 foreign to his aim as he carried out his work. The 

 result is a memoir presented by its author to the 

 Geological Survey, and thus to the general public, 

 accompanied by a map reproduced on the scale of 

 one inch to one mile. Mr. Greenly 's generosity has 

 led him even to provide much of the cost of pub- 

 lishing these two handsome volumes. Geologists 

 in many countries will associate themselves warmly 

 with the thanks so well expressed by Sir Aubrey 



F.o. 



-The foldioj of the Mona complex, fr >m the South Stack, Holyhead. Height seen 445 ft. From " The Geology of Anglesey," by permission 



of His Majesty's Stationery Office. 



Edward Greenly retired from the staff of the Geo- 

 logical Survey to devote himself to the geology 

 of the island. For twenty-four years he pursued 

 his investigations, recording' his results line by 

 line upon the six-inch maps. The antique com- 

 plex,^ offering problems similar to those faced by 

 him in the Scottish highlands, was his first object 



1 (r)" The Geology of AnKlesejr." By Edward Greenly. (Memoirs of 

 the Geological Survey.) Vol. 1.. pp. jtl + 388-(-pl .les i-xxvi ; Vol ii 

 pp 389-98o+Platesx<viB-lx + i6 folding plates. (Southampton : Ordnance 

 Survey Office; London: E. Stanford, Ltd., iqio.) Price two vols 

 3 guineas net. ' *' 



(2) Geoloaical Survey of England and Wales " Anjlesey." Colour- 

 prmted map, one mcS to one mile. (Southampton: Ordnance Survey 

 Office, 1930.) Price 21. 6rf 



NO. 2661. VOL. 106I 



Strahan in his preface. May we be allowed to 

 join also in the author's gratitude to Mrs. Greenly 

 for her co-operation in long years of preparation? 

 A comparison of the map, which is so clearly 

 produced, in spite of all its detail, with the hand- 

 coloured sheets issued in 1852 will best reveal 

 the changes of view that studies in other areas 

 have brought about. When J. F. Blake, in 1888, 

 read his memorable paper on "The Monian 

 System of Rocks," we were still in the grip of 

 what may be called the pre-cambrian controversy. 

 Lapworth had recently published his work on the 

 north-western highlands of Scotland ; the Geo- 



