Eeviews — Geological Survey — Stoke-on' Trent. 565 



Brook Waterworks, identified by Mr. E. Kidston, and published in 

 the Transactions of the North Staffordshire Field Club for 1889. 



Chapter iii deals with the Lower and Middle Coal-measures : an 

 artificial horizon, the Ash Coal, is taken as the base of the Middle 

 Coal-measures. We ourselves should have felt inclined in the first 

 place to make no subdivision, or to have placed it at the horizon of 

 the 7 foot Banbury seam. Mr. Gibson seems doubtful of the utility 

 of this subdivision, and it is difficult to see what good purpose it 

 serves. He has wisely not given different colours to the two 

 divisions on the map. 



The lowest part of the coalfield, below the Winpenny Coal, is 

 not well known, and none of the coals are now worked. The 

 measures are about 1,200 feet thick. Garbonicola acuta, Lingula 

 Credneri? occur in them at different horizons, as well as the 

 marine fossils indicated. A note at the bottom of p. 19 informs 

 us that the section marked with an asterisk is by Mr. Barrow. 

 The asterisk has been omitted, but presumably the article on the 

 Shaffalong Coalfield is referred to. The important seam in the 

 Cheadle Coalfield known as the Froghall ironstone, a hajmatite 

 which lies on or a few feet above the first grit in the neighbouring 

 Cheadle Coal basin, has not been proved to be present either in the 

 Shaffalong or Biddulph Valley basins. 



It is pointed out that throughout the Coal-measures in North 

 Staffordshire the measures between the coal-seams thin out rapidly 

 to the west and thicken to the north. It is a well-known fact, and 

 the Millstone Grit and Pendleside Series also thicken rapidly to the 

 north and north-east, indicating the direction of the land whence 

 the detrital matter was obtained. In connection with this subject 

 we are informed (p. 25) : "On compai'ing the shaft sections in this 

 area [Biddulph] with those in the Longton district it will be noticed 

 that there is a larger proportion of sandy material in the northern 

 area." Naturally sand grains, being heavier, would not be transported 

 so far as the lighter shale particles. 



The nodules with marine fossils over the 7 foot Banbury seam at 

 Lycett Colliery are strongly suggestive of the fauna and general 

 character of the roof of the Bullion coal of Lancashire. The different 

 character of the coals as regards cokeing (spelled 'cooking,' line 16, 

 p. 32) is of interest, those on the east side of the coalfield not having 

 this quality, but the same seams on the west cokeing well. 



Chapter iv deals with the Upper Coal-measures, and is well worth 

 study. Mr. Gibson has previously indicated the main features of 

 his discoveries and views on this important series of rocks. It is 

 not therefore necessary to give his table here in detail. It suffices 

 to say that there are four well-marked subdivisions, which he names 

 the Keele Series, 700 feet ; Newcastle-under-Lyme Series, 300 feet ; 

 the Etruria Marls, 800 to 1,100 feet ; the Blackband Series, 300 to 

 450 feet; of which the last is of economic importance, as it contains 

 several valuable Blackband ironstones resting on coals which are 

 worked together, although on p. 17, line 19, it is stated that the 

 Upper Coal-measures contain no workable seams of coal. It is of 



