12 GEOLOGY* 



Passes under review the Drift-deposits of Lancashire, Cheshire, the 

 Lake District, the Avon, Hoxne, Bedford, Thames Valley, Medway, 

 Folkestone, S. and S.W. coasts, and French coast. The sequence of 

 beds is described ; and the author believes that the succession of glacial 

 beds in Hertfordshire and the E. of England can be correlated with 

 that of Lancashire. The glacial submergence was greatest to the 

 N.W. ; the country S. of the Thames was probably not submerged. 

 In the N.W. of England many of the valleys are pre-glacial ; these 

 were largely filled up during the glacial period, and have been re-exca- 

 vated since. The valley of the Lower Thames is post-glacial. W. T. 



Desmarets, Nicolas. L'Ancienne Jonction de I'Angleterre k la 

 France ; ou le Detroit de Calais, sa formation par la rupture de 

 risthme, sa topographic, et sa constitution geologique. Paris, 

 12mo, 1875, pp. xvi, 114 ; map and diagram. [Reprint of a Prize 

 Essay at the Academy of Amiens, in 1751.] 

 The first part treats of the reasons, historical and physical, for be- 

 lieving that at one time an isthmus joined England to the continent — 

 the gradual narrowing of the sea, and the similarity of the strata and 

 of the hills on either side, being dwelt upon. The second part treats 

 of the means by which the isthmus has been destroyed. Volcanic action 

 is rejected, there being no evidence of it. Detailed description is 

 given of the action of weather and frost on rocks, especially on chalk 

 cliff's ; and it is shown that the constant wearing action of the tides, 

 aided by the weather, suffices to wear away cliff's. The rapid narrowing 

 of the channel, then closed at the apex, would give great force to the 

 western waves. Komney Marsh is believed to have been formed from 

 the material worn away. Frequent illustrations are drawn from coast- 

 action in other parts of the world. W. T. 



Dixon, James S. On an Ancient River-course at Auchinlea, parish 

 of Shotts. Proc. Glasg, Nat. Hist. Soc. vol. ii. pt. 1. 



Gives an account of a river-course in the main coal seam of the 

 Lanarkshire coal series by the Midhill Pit. The depth from the sur- 

 face at one point was 130 feet ; hence the author thinks that the river 

 must have been of long duration. J. E. T. 



Du Noyer, G. V., Prof. J. B. Jukes, and Prof. E. Hull. Explanatory 

 Memoir to accompany sheets 102 and 112 of the Maps of the 

 Geological Survey of Ireland. With Palaeontological IS'otes by 

 W. H. Baily. Edit. 2. Pp. 75. 19 woodcuts. 8vo. Dublin. 

 The chief places in the district are Dublin, Kingstown, Malahide, 

 Swords, and Skerries, with Howth and Lambay Island. A considerable 

 portion of the Dublin mountains is included to the south. The forma- 

 tions are : — Granite, Trappean Ash, Felstone Porphyry, Diorite ; Cam- 

 brian, L. Silurian, Carboniferous (Limestone and Shales), Pleistocene 

 (Drift), Bog, Alluvium. The granitic rocks stretch southwards from 

 near Kingstown into the Dublin mountains, in which localities the 

 L. Silurian, often highly metamorphosed, is also found. At Howth the 

 Cambrian beds appear, and the northern portions of the district are 



