84 Revieus—A. G. M. Thomson— Old Red Sandstone. 



Carboniferous beds of Central Scotland. On this interesting poii»t, 

 which Dr. Traquair leaves unexplained, we turn to the later paper 

 by Dr. Peach and Dr. Home. These authors deal with the 

 structure of the Canonbie Coalfield, which occupies a small tract 

 between the Liddel Water and the river Esk in the south-eastern 

 part of Dumfries-shire. They describe the Glencartholm shales as 

 occurring in a volcanic group, above the Fell Sandstones, and 

 probably below the horizon of the Scremerston coals of the eastern 

 border counties. The shales form a rich paleeontological zone, which 

 was discovered by Mr. A. Macconochie, and found to contain a large 

 number of new genera and species, including plants, brachiopods, 

 lamellibranchs, cephalopods, scorpions, eurypterids, ostracods and 

 other Crustacea, as well as fishes. The zone has not elsewhere 

 been detected, but some of the many species have been found in the 

 Calciferous Sandstone group elsewhere in Scotland, and Dr. Peach 

 is confident that other species will likewise be found away from 

 the Canonbie district. 



In their description of this district the authors begin with the 

 Old Red Sandstone, which has yielded scales of Ilolopti/chius ; and 

 they then give details of the strata and fossils of the Lower and 

 Upper Carboniferous, the Millstone Grit being taken as the base 

 of the Upper division. Workable coals occur at various horizons 

 above the Glencartholm beds ; and some estimates are given of 

 the coal-supply in concealed portions of the area. The work is well 

 illustrated by a coloured geological map and sections, and it contains 

 an exhaustive account of what is known of the ai'ea from a scientific 

 and practical point of view. 



IV. — The Position of the Old Red Sandstone in the 

 Geological Succession. By A. G. M. Thomson, F.G.S. 8vo ; 

 pp. vi, 224. (Dundee : John Leng & Co., 1903.) 

 rpHIS book is divided into five sections, but otherwise it has no 

 \_ headings, no illustrations, no details of sections, not even an 

 index. The object of the author is to saggeat " certain hypotheses, 

 well supported by circumstantial evidence," and he proceeds to 

 state that " These hypotheses, in the first place, are intended to 

 shew that the conditions under which the Old Red Sandstone was 

 produced may not have been of the character of inland lakes without 

 free connection with the sea ; and, in the second place, that the 

 conditions which produced the Old Red Sandstone way not have 

 begun only after the close of the conditions which produced the 

 youngest of the Silurian beds, nor have terminated before the date 

 of deposition of the oldest of the Carboniferous beds." 



The entire work appears to us to be a case of much ado about 

 nothing. There is not a single reference to any other published 

 view, otherwise the author might have spared himself the long and 

 laboured arguments to support hypotheses with which perhaps 

 a good many geologists would be inclined to agree. He might at 

 any rate liave fortified himself with reference to Hypothesis No. 1 

 by quoting the Rev. W. S. Symouds, ''Records of the Rocks," 1872,. 



