32 Reviews—Dr. Geikie—Tertiary Volcanic Action. 
O59 JE se a A 
I.—Tur History or Voxucantc ACTION DURING THE TERTIARY 
Prriop 1n THE BritisH Istus. By ArcHiBaLD Gerrxiz, LL.D., 
F.R.S., Director-General of the Geological Survey of the United 
Kingdom. (Transactions of the Royal Society of Edinburgh, 
vol. xxxv. 1888, pp. 21-184, with 2 Maps and 53 Woodcuts. 
Reprinted, 4to. Edinburgh, R. Grant & Son. Price 18s.) 
\HE work before us, probably the most important of the original 
papers by the author, must be read by every one devoted to the 
special study of volcanic action ; at the same time it contains results 
of such high interest to all geologists, that in due course it will 
doubtless be regarded as one of the ‘ classic’ memoirs of this prolific 
age. 
ae the outset the author gives a brief sketch of the labours of 
previous observers. Foremost among these was Macculloch, and of 
his great work on the Western Islands of Scotland, Dr. Geikie says, 
«Few single works of descriptive geology have ever done so much 
to advance the progress of the science in this country.” It is 
pleasant to see the labours of the pioneers so fully acknowledged, 
and in reference to Ami Boué, who published in 1820 his Essai 
géologique sur l’ Ecosse, it is remarked that “the value of this work as 
an original contribution to the geology of the British Isles has 
probably never been adequately acknowledged.” 
From time to time during the past 30 years Dr. Geikie has pub- 
lished the results of his own observations on the volcanic rocks of 
Scotland, but it was not until 1879 that he ‘‘ appreciated for the first 
time the significance of Richthofen’s views regarding ‘massive’ or 
‘fissure-eruptions,’ as contradistinguished from those of central 
volcanoes like Etna or Vesuvius;” then, however, when traversing 
some portions of the volcanic region of Wyoming, Montana, and 
Utah, he “saw how completely the structure and history of these 
tracts of Western America explain those of the basalt-plateaux of 
Britain.” 
In the mean time an elaborate Memoir by Prof. Judd on the 
Ancient Volcanoes of the Highlands was read before the Geological 
Society of London; and it is important to notice that the conclusions 
of Dr. Geikie are to a very large extent at variance with those of 
Prof. Judd. The latter had recognized the basal wrecks of five 
great central volcanoes in the Western Islands; whereas Dr. Geikie 
has not been able to discover evidence of any great central volcanoes, 
and has found the order of outflow of the successive groups of rocks 
to have been the reverse of what Prof. Judd believed it to be. 
In the present memoir Dr. Geikie commences his history of 
volcanic action with an account of the basic dykes, which traverse 
so large a part of Scotland, and extend also into the North of Ireland, 
the Isle of Man, and the North of England. Of these dykes, that 
in Cleveland is one of the best-known English examples. The 
author then describes the great volcanic plateaux, which, in spite of 
vast denudation, still survive in extensive fragments in Antrim and 
