22 GEOLOGY. 



Ireland, and over the greater part of England. The later ice-sheet was 

 thinner and less enduring than the earlier ; for it has not destroyed 

 all the glacial beds produced during the second period. The ice-sheet 

 gradually shrank into valley-glaciers. Where the retreat of the ice 

 was rapid, no marginal deposits were formed ; but where there were 

 pauses in the retreat of a glacier, kaims, eskers, and moraines have 

 been left. The author enters into some detailed arguments to show 

 that eskers are not marine, but are more likely to have been formed at 

 the end of a glacier. The gravel-terraces along the river-valleys are 

 believed to be glacial, formed when the centre of a valley (or the bed 

 of a stream) was occupied by a glacier; into the hollows between the 

 glacier and the hills gravel would be washed down. The glaciation of 

 the western coast of Scotland has been more extreme than that of the 

 eastern coast. Ear more rain falls on the west coast than on the east 

 coast ; and the author infers that a like distribution of snow occurred 

 during the glacial period. W. T. 



Jolly, W. Second Report on Eossils from localities of difficult access 

 in North- Western Scotland. Rep. Brit. Assoc, for 1873, p. 412. 



Eossils have only been found near Durness ; these have not yet been 

 determined. It is desirable that search should be made along the strike 

 of the limestone between Eribol and Skye. W. T. 



Jones, Prof. T. R. Water Supply and " Divining Rods." Geol. Mag. 

 dec. 2, vol. i. p. 579. 



Notes the occurrence of the Oyster-bed of the W^oolwich and Reading 

 series at Bussock Camp, three miles N. of Newbury. This was found 

 in sinking a well, in which no water was obtained. The spot had 

 been chosen by means of the divining-rod, by an expert, *' who had 

 the reputation of having been most successful at Sandleford, near 

 Newbury!" W. T. 



JuDD, J. W. The Secondary Rocks of Scotland. Second paper. On 

 the Ancient Volcanoes of the Highlands, and the Relations of their 

 Products to the Mesozoic Strata. Quart. Journ. Geol. Soc. vol. xxx. 

 pp. 220-801, plate (map and sections). 

 There have been two great periods of volcanic activity in Scotland 

 — one, extending from the commencement of the Old- Red-Sandstone 

 period down to the close of the Palaeozoic era, the other during 

 nearly the whole of the Tertiary period. During each of these vol- 

 canic periods a great extent of continental land appears to have existed 

 in the same areas. During each volcanic period the extension of fel- 

 spathic lavas has preceded that of the basaltic varieties : in the case 

 of the Palaeozoic volcanoes the transition from one kind to the other 

 appears to have been gradual ; with the Tertiarj^ volcanoes, however, 

 the eruption of highly silicic lavas was followed by an interval of rest, 

 after which highly basic rocks were ejected from the same vents. The 

 older volcanoes ranged N.E. and S.W., coinciding with the direction 

 of the main axis of upheaval. The Tertiary volcanoes ranged N. and 

 S. There appears to have been no volcanic outburst in Scotland 



