Oct. 19, 1876] 



NATURE 



557 



yet lost none of the vigour and elasticity of youth, have 

 of course rendered much of the information contained in 

 it obsolete. The only work of more recent date which 

 occupies somewhat the same ground is D'Archaic's " His- 

 toire des Progr&s de la Gdologie," which aimed at doing 

 for all those portions of the globe which had been geolo- 

 gically explored, what Conybeare and Phillips had at- 

 tempted for England alone. This work is one of the very 

 highest order of merit ; its author being equally dis- 

 tinguished for his industry in the compilation of 

 materials, his skill in arranging them, and his bold- 

 ness and originality in generalising from them. But 

 such a design as that of the " Histoire des Progr^s " was 

 perhaps too ambitious to be within the compass of the 

 efforts of any single individual ; at all events, after the 

 portions relating to the Tertiary and Secondary strata 

 had appeared in a series of eight volumes, between the 

 years 1847 and '60, the work, which had up to that time 

 been published by the Geological Society of France under 



the auspices of the Minister of Public Instruction, was 

 finally abandoned. 



It will be seen, therefore, that Mr. Woodward's 

 handy volume, the title of which is given above, 

 appears very opportunely ; and, supplying as it does 

 a real need of the geological student at the present 

 time, it is certain at once to take its place as the 

 most useful general work of reference on English Geology 

 which exists. After a careful perusal of it, we find 

 scarcely anything calling for qualification of those terms of 

 high commendation in which we are constrained to speak 

 of its general accuracy and excellence of arrangement ; 

 of the happy way in which the mean has been hit between 

 conciseness of description and fulness of detail ; and of 

 the manner in which the work has been made to include 

 the latest results of geological research. 



At the time when Conybeare and Phillips wrote, many 

 portions even of those Secondary strata of England, the 

 successful classification of which had been the chief among 



Fig. I.— The Cheddar Cliffs. 



the triumphs of William Smith's genius, were as yet 

 almost unknown to geologists ; the labours of Sedgwick 

 and Murchison, which were destined to replace the con- 

 fusion that reigned among all the older deposits, by the 

 clear succession of the Cambrian, Silurian, and Devonian 

 systems, had not^ then commenced ; add as yet the 

 paltEontological studies of Lyell and the stratigraphical 

 researches of Prestwich had not dispelled the almost 

 equal obscurity which prevailed concerning the order of 

 the Tertiary formations. There are perhaps few ways in 

 which the strides made during the last fifty years in our 

 knowledge of the geology of this country can be more 

 vividly realised than by a comparison of the sketch-maps 

 prefixed to the volume of Conybeare and Phillips, and to 

 that of Mr. Woodward respectively. Such a comparison 

 will render strikingly apparent the great advances which 

 have been made in developing the true structure of the 

 country, both through the researches of private individuals 

 and the labours of the National Survey ; and it will 



equally serve to demonstrate the necessity of such a work 

 as that which Mr. Woodward has now given to us. 



The avoidance by the author of this work of all refer- 

 ences to the equivalent formations on the continent of 

 Europe, or even to those in other parts of the British 

 Islands — although perhaps a necessity dictated by the 

 limits he had set himself — creates some serious difficulties, 

 which are more especially felt when questions of classifi- 

 cation come to be treated of. It is altogether vain to 

 hope that such problems can be decided by an appeal to 

 the Enghsh representatives of the formations alone. To 

 discuss, for example, the question of the classification of 

 the Silurian, Devonian, and Permo-Triassic (Poikilitic) 

 formations, without any reference to the typical develop- 

 ments of these strata in Bohemia, the Eifel, and Central 

 Germany respectively, is surely a most unsatisfactory 

 and inconclusive proceeding. 



In adopting Sedgwick's classification of the Cambrian 

 and Silurian strata instead of that of Murchison, the 



