Reviews—Geological Survey of Great Britain. 313 



Coal-basins of North StafforclsHre. Both of these coal-tracts are 

 abruptly bounded on the west by the great " Eed-rock Fault ; " and 

 on the east, from beneath them, come out the barren Millstone-grit, 

 and underlying Yoredale shales and Mountain-limestone. These, 

 broken by great faults, undulate in broad troughs and arches over 

 the High Peak district, and then pass beneath the great coal-fields of 

 Western Yorkshire. In the country under notice, some other patches 

 of Coal-measures have been preserved in the great synclinal of 

 Millstone-grit, called the Goyt Trough. To point out the exact 

 definition of all these coal-areas, and the real position and out-crop 

 of their several coal-seams, has been, of course, one of the main 

 objects of the Geological Surveyors, — these points having direct prac- 

 tical bearings on the commerce and welfare of this important manu- 

 facturing district. With the aid of the many proprietors, managers, 

 and others, who are duly mentioned in the Preface, the details of the 

 numerous coal-workings have been got together, and scientifically 

 collated, and now plainly illustrated for the benefit of all. Great 

 good must arise from this ; for those now working the coal can learn 

 with certainty the relationship of the strata in their several pro- 

 perties to those in the neighbourhood, and may be spared uncertainty 

 and expense in further operations. Moreover, in the immediate 

 vicinity of Stockport, some square-miles of " red-ground " along 

 the great fault are shown to consist of Permian strata, close upon 

 the Coal-measures, and allowing these latter to be reached, and not 

 of the red strata of the Triassic series high up, overlying both Per- 

 mian-beds and Coal-measures, and too thick to allow of profitable 

 sinking. 



Other points of interest and, indeed, results of much value, are to be 

 found in the admirable delineation and description of the geological 

 structure of the district, formed (beneath its coating of Boulder-clay, 

 sand, and gravel,) simply of a succession of Carboniferous, Permian, 

 and Triassic strata, broken, however, by innumerable faults, mainly 

 with a N.S. direction, but often transverse and oblique. The general 

 geological structure and its relation to the hills and rivers, the nature 

 of faults, landslips, the causes and results of denudation, and other 

 alKed subjects, are here treated of by really good observers, and clear 

 and cautious thinkers. The illustrative sketches and diagrams, as 

 well as the reduced map, are admirable ; and, whilst the coal-owners 

 and " practical men " will have these explanations of the Maccles- 

 field map at their elbow for constant reference, pure geologists will 

 scarcely find a page but must interest them, either by descriptions, 

 elucidations, or suggestions relating to the various deposits treated of 

 (Palceozoic, Mesozoic, and Post-Tertiary), as to their origin, modifica- 

 tions, and actual condition. The Appendix, enumerating the Fossils 

 found in the several sets of strata of the district, is, in itself, an 

 important addition to paleeontology. Eecurring to the Memoir 

 itself, we must remark that Messrs. Hull and Green have taken 

 much pains to explain the relationship of the "Yoredale Series" in 

 Yorkshire, Derbyshire, and Staffordshire ; and they have with great 

 care worked out the different members of the " Millstone-grit 



