246 Professor J. W. Gregory — The Solway Basin — 



this identification is responsible for the difficulty in the inter- 

 pretation of the geology of the Solway-Carlisle basin, its careful 

 reconsideration is justifiable. 



If Mr. Holmes' identification of the rock from the Abbey town and 

 Bowness bores be correct, there would be a double series of Gypseous 

 Shales, one above and one below the ' St. Bees Sandstone. The 

 existence of the Lower Gypseous Shales is undoubted ; they separate 

 the St. Bees Sandstone from the Penrith Sandstone. The Geological 

 Survey maps express some hesitation as to whether this series should 

 be included in the Permian or the Trias, but they show it as certainly 

 situated between the St. Bees and the Penrith Sandstones. 



The claim for the existence of the Upper Gypseous Shales rests 

 upon the identification of the sandstone at the bottom of the Bowness 

 and Abbeytown bores as the St. Bees Sandstones. It may appear 

 most unlikely that such an expert in the geology of North- Western 

 Cumberland as Mr. Holmes could be mistaken in this determination ; 

 and his view has been further recommended by the improbability of 

 the conclusion offered as the alternative, namely, that the Stanwix 

 Shales are the eastern continuation of the Gypseous Shales of the 

 Great Orton and Bowness bores. Nevertheless, several considerations 

 suggest that the sandstone at the base of the Abbeytown and Bowness 

 bores is really the Penrith Sandstone. 



1. Though the two formations are usually easily distinguished, 

 mistakes are possible, as some layers of the St. Bees Sandstone contain 

 redeposited Permian material ; most of the sandstone in question was 

 clearly not typical St. Bees Sandstone. 



Mr. P. Fleming Smith, the Manager of the Vivian's Boring and 

 Exploration Co., Ltd., the present title of the firm which, as the 

 Cumberland Diamond Boring Co., put down the bore in 1875-6, tells 

 me that the report-book of the bore shows that few cores were 

 obtained from the last 200 or 300 feet and none from the lowest beds. 

 The report-book is supported by the testimony of one of the charge 

 men on the staff of the Company who worked at the boring. He 

 states that the lowest bed " of soft sandstone made no core ". Hence 

 any identification of the rocks at the bottom of the bore must have 

 been based on fragmentary material. 1 The debris of the St. Bees 

 Sandstone and Penrith Sandstone might easily be mistaken ; and 

 under those circumstances the determination of the material at the 

 lower end of the bore as St. Bees Sandstone cannot carry weight 

 against the general stratigraphical evidence. 



2. Mr. Holmes was probably predisposed by his classification of 

 the Bed Bock Series of Cumberland to regard these sandstones as the 

 St. Bees Sandstone, for he made this identification also for the 

 sandstone of the Bowness bore, of which the only description is " red 

 stone ". 



1 In the Carlisle Memoir, issued 1899 (p. 20), the identification of the soft 

 red sandstone as the St. Bees Sandstone is advanced on the examination by 

 Mr. Holmes and his late colleague R. Russell of " the cores showing this lowest 

 bed ". As no cores,were obtained from that bed if the identification were based 

 on cores, they must have come from some upper part of the boring or from 

 another locality. 



