2 A Retrospect of Geology for Forty Years. 



Some articles, indeed, might with benefit have been curtailed, a few 

 might perhaps have been omitted without detriment to science, while 

 here and thei'e asperities in correspondence might have been softened 

 or removed with evident advantage. 



Our First Decade was characterized by many articles and much 

 discussion on various forms of Denudation, in which Scrope, John 

 Ruskin, Jukes, Colonel George Greenwood, 0. Fisher, D. Mackintosh, 

 Hull, Whitaker, Green, Kinahan, Topley, and others took part. 

 Escarpments and valleys, lakes, and the relative importance of 

 sea versus rivers came again and again to the front, the last- 

 named subject being dealt with in a masterly way by Whitaker 

 in his classic essay on Subaerial Denudation. The origin of the 

 Chesil Beach and the adjacent features was considered, and even the 

 ancient valley system of Pre-Triassic times in the Bristol area and 

 Charnwood Forest, which has quite lately been a subject of interesting 

 observations, was briefly discussed by G. Maw. 



Glacial geology and the causes of changes of climate occupied the 

 attention of S. V. Wood, jun., James Geikie, James CroU, W. Boyd. 

 Dawkins, and D. Mackintosh ; and Geological Time was also brought 

 before our readers. 



The study of Igneous rocks with microscopic aid came into 

 prominence. Interest was stirred up by P. H. Lawrence's trans- 

 lation of B. von Cotta's work, " Rocks Classified and Described." 

 David Forbes and Samuel Allport dwelt on the importance of the 

 study and gave an impulse to research. Forbes and Sterry Hunt 

 entered into controversy on certain questions of chemical geology. 



The recognition of ' Eozoon ' as a foraminifer was in these early 

 days largely accepted. It was held to have built up in reef-like 

 masses the limestones since altered into marbles in the great 

 Laurentian gneiss of Canada. Eozoonal structure was also seen 

 in the green and white marble of Connemara. 



Sir Roderick Murchison wrote on the Laurentian rocks of Britain, 

 Bavaria, and Bohemia; and cores of the ancient gneiss (now grouped 

 as Archaean) were recognized by H. B. Holl at Malvern and by 

 others elsewhere. 



Hicks, aided at first by Salter, commenced his brilliant researches 

 among the Lower Palasozoic rocks of Wales, and the results of some 

 of these, together with the now classic paper of T. Belt on the 

 Lingula Flags, are included in the volumes. Hughes dealt with 

 the break between the Upper and Lower Silurian rocks of the Lake 

 District, in a paper which (if we are rightly informed) found little 

 favour in the eyes of Murchison. 



Other topics received treatment ; J. Ruskin wrote on Banded 

 and Brecciated Concretions, S. P. Woodward on Banded Flints, 

 John Morris on the Oolites and Lower Cretaceous rocks, and Meyer 

 on Cretaceous rocks, while G. Maw described interesting pockets 

 of white clay, etc., in the Carboniferous Limestone of North Wales, 

 Derbyshire, and North Staffordshire. 



In the Second Decade the desii-ability of having a detailed 

 record of geological and palseontological literature was brought 



