Reviews — The Work of the Geological Survey. 471 



II. — Memoirs of the Geological Survey of England and 



Wales. 



1.— The Geology of the South Wales Coalfield. Part IV : The 

 Country around Pontypridd and Maes-Teg, being an account of 

 the region comprised in Sheet 248 of the Map. By Aubrey 

 Strahan, M.A., F.G.S., R. H. Tiddebian, M.A., F.G.S., and 

 Waloot Gibson, B.Sc, F.G.S. 8vo; pp. vi and 134, with 

 plate of sections and 6 text illustratious. (Issued July, 1903 ; 

 preface dated 28th February, 1903. Price Is. 6d.) Illustrating 

 Sheet 248 of the Geological Map of England and Wales (scale 

 1 inch to 1 mile), colour printed. (The map is sold separately, 

 price Is. 6d.) 



2. — The Geology of the Cheadle Coalfield. By George Barrow, 

 F.G.S. 8vo; pp. iv and 62, with 2 illustrations in the text 

 and geologically coloured map of the Cheadle Coalfield. Price 

 with map, 2s. (Preface dated 12th March, 1903.) 



3. — Summary of Progress of the Geological Survey of the United 

 Kingdom and Museum of Practical Geology for 1902, with 

 Introduction by J. J. H. Teall, M.A., F.R.S., Director. 8vo ; 

 pp. iv and 240, with 9 illustrations in the text. London, 1903 

 (received 20th August, 1903). Printed for H.M. Stationery 

 OflSce ; sold by E. Stanford, London, etc. (or of Messrs. 

 Dulau & Co., 37, Soho Square, W.). Price Is. 



rpHB Geological Survey memoirs recently published, whose titles 

 X we quote above, are of considerable interest. 



1. The first of these is a continuation of " The Geology of the 

 South Wales Coalfield," ^ comprised in Sheet 248, and is the fourth 

 part of the memoir descriptive of this region, including the 

 important part of the coalfield extending from Pontypridd on the 

 east to Cwmavan on the west, and from Aberaman and Glyn-corwg 

 in the north to Llantrisant and Mynydd Margam in the south, 

 embracing the greater part of the range of the best steam-coal. 



Sir H. T. De la Beche, Sir W. E. Logan, and Mr. D. H. Williams 

 made the first survey of this area on the old map ; probably most 

 of the work was by De la Beche himself, but the western part was 

 surveyed by Logan before his connection with the Geological 

 Survey. The original maps were exhibited by Logan in 1837 at 

 the British Association in Liverpool, and attracted the attention of 

 De la Beche, with the result that they were handed over to the 

 Geological Survey and incorporated in the official maps, while 

 Logan himself became a member of the staff. Sheet 36 was 

 published in or before the year 1845. 



The re-survey was made on the 6 inch scale, under the super- 

 intendence of Mr. Strahan, and published in 1899. The eastern 

 part of Sheet 248 was surveyed by Mr. Strahan, the south-western 

 part by Mr. Tiddeman, and the northern part by Mr. Gibson. 



1 See previous review, Geol. Mag., June, 1903, p. 269. 



