380 SCIENCE PROGRESS 



coalfield of Mons with the South of England. It is to Godwin- 

 Austin that the credit belongs, for he was the first to elaborate 

 the theory and to trace the connection between cause and effect, 

 in that he first enunciated the now generally accepted principle 

 that recent folds in the earth's crust correspond to the deep- 

 seated folds in the basement rocks beneath. In other words, 

 the line of a long-since buried mountain-chain could be detected 

 by physical features at the surface at the present day. In the 

 hand of an experienced geologist this principle is a most 

 valuable instrument, but it requires care and deliberation in its 

 employment. 



At the beginning of the Permian Epoch, those infinitely 

 remote days which followed the deposition of the Coal 

 Measures, the latter extended in an unbroken sheet over vast 

 areas of the world. It is probable that a continuous forest 

 stretched from South Wales across Europe into Asia, perhaps 

 even as far as Japan. During the Permian Epoch a great 

 series of earth movements set in, attributed to the contraction of 

 the earth's crust due to the secular cooling of the interior of 

 the planet. As the earth shrank, wrinkles were formed on its 

 surface ; these wrinkles ran in two main series, one north and 

 south and the other east and west ; the tops of these ridges 

 were exposed to the inclemencies of the weather, and the 

 deposits of Coal Measures were washed away from these 

 summits, down into the valleys where they reinforced the 

 already existing deposits. The tops of these wrinkles or folds 

 are termed anticlines, and the lower parts synclines. It follows 

 that, if we could trace these on the map, we could mark out the 

 coalfields, or coal-basins, which lie in the synclines, and avoid 

 wasting trouble and time by looking for coal on the anticlines. 



This is exactly what Godwin-Austin did. He traced a great 

 anticline across the south of England, from Pembroke across 

 the Mendips, past Kingsclere and Maidstone, along the North 

 Downs towards Folkestone, where it makes a bend to the 

 south and is continued in France from Cape Grisnez along the 

 hills of Artois into Europe. This is called the Pembroke- 

 Mendip anticline by Boyd Dawkins, but is more generally 

 known as the Axis of Artois. It is really a buried mountain 

 range, composed of very ancient rocks, older even than the 

 Coal Measures, which repose upon the floor thus provided. 

 These ancient rocks appear at the surface in Pembroke ; then 



