136 Reviews — A. W. Rogers — Geology of Cape Colomj. 



of Good Hope, to promote the study of Natural Science in South 

 Africa, and with the consent of the Geological Commission the work 

 was intrusted to Mr. A. W. Rogers. 



The choice of author could not have been more happily made, for, 

 in conjunction with Mr. E. H. L. Schwarz, Mr. Eogers has surveyed 

 large tracts in the Colony during the past eight years, as well as 

 making himself thoroughly acquainted with the literature of the 

 subject. 



The task submitted to Mr. Eogers was no easy one ; but so skilful 

 has been his performance of it that only those who have attempted 

 to find light amidst the chaos of South African geology will realize 

 its magnitude. Each of the many problems is adequately dealt 

 with and yet kept in fitting proportion. The style is clear and 

 concise, the natural result of a complete grasp of the subject. 

 Simplicity of language, modesty of statement, adherence to fact, 

 characterise the whole work. The descriptions are necessarily brief, 

 but they are sufficient ; there is no burdensome detail such as 

 German writers on African geology abound in. The work of 

 others, including that of his colleagues, receives due recognition ; 

 but the major portion of the volume really represents the results 

 obtained by the field stafi" (three in number) of the Cape Geological 

 Commission, of which Mr. Rogers is the oldest member. 



The book will be found useful to many classes of readers. To 

 those wholly ignorant of South African geology it will form 

 a pleasing introduction ; to the student, lost in the maze of conflicting 

 accounts, it will tell what to follow and what to avoid ; while the 

 specialist, in almost every branch of geology, will find new material 

 to illustrate and amplify the particular line of research on which he 

 may be engaged. 



In the opening chapter the author describes the chief physical 

 features of the colony, its general geological outlines, order of the 

 rock groups, followed by a brief but clear account of the regions 

 occupied by the various rock formations and their tectonic 

 relationship. 



The rocks of pre-Cape age are dealt with in chapters ii-iii. The 

 reader will here find a summary of the work done among these old 

 rocks, the results being mainly obtained by the officers of the Cape 

 Survey. They contain problems of a mineralogical, petrological, 

 stratigraphical, and dynamical character, many of them of worldwide 

 interest, and of especial importance in connexion with the age and 

 succession of the older rocks of other parts of South Africa. Wisely 

 enough, however, the author makes no attempt to force a correlation, 

 either between the two areas in which this complex of rocks occurs 

 in Cape Colony or with the far distant region of the Transvaal. 

 We are pleased to see references to, and ample recognition of, the 

 admirable researches of G. W. Stow in Griqualand West. 



The question of the order of the succession of the different 

 members of the Cape System (Table Mountain Sandstone, Bokkeveld, 

 and Witteberg Series) and their relationship to the pre-Cape rocks is 

 discussed, in conjunction with a description of the rocks, in chapter iv. 



