1888 - 89 .] Meetings of the Society. 817 
has already received the award of the Makdougall-Brisbane 
medal. 
Though their literary grace will doubtless make many of his 
writings classics in the literature of the science, it is perhaps on 
account of his original work in the study and classification of the 
igneous rocks of Scotland that he will most deserve the recognition 
and gratitude of geologists. With the exception of Maclaren’s 
excellent detailed work among the rocks of Arthur’s Seat and the 
Pentland Hills, all previous writers had looked upon the volcanic 
rocks of Scotland as mere eruptive mineral masses. Mr Geikie was 
the first to treat them, as a whole, from a chronological point of 
view as the records of a long succession of volcanic eruptions, the 
relative geological dates of which could be certainly fixed. In 1861 
he contributed to this Society a paper giving a first sketch of a 
classification of the volcanic phenomena of Scotland, which may be 
said to have struck the keynote of all his subsequent researches in 
this subject. The more detailed studies of later years have indeed 
enabled him to modify some of the views there enunciated, but the 
main broad outlines remain as they were originally traced. Year 
by year he has filled in these outlines from a detailed study in the 
field. He was thus enabled to add a new chapter to the volcanic 
history of his native country by the discovery of the remains of 
volcanoes of Permian age in the counties of Ayr and Dumfries, of 
the existence of which he was ignorant in 1861. 
After many years of investigation he gave to this Society his 
paper upon the “Carboniferous Volcanic Pocks of the Basin of the 
Forth,” which was published in our Transactions in 1879. It was 
doubtless from the exhaustive manner in which the microscopic 
structures of these rocks was there worked out that the eyes of 
Continental geologists were opened to the fact, long insisted upon 
by him, that there is really no essential difference between the pro- 
ducts of Palaeozoic volcanoes and those of the present day. 
Some of Mr Geikie’s earliest labours among the volcanic rocks 
were devoted to the great basaltic tracts of the Inner Hebrides. 
They seem to have had a peculiar fascination for him, for we find 
him returning to them again and again during more than thirty 
years. In the midst of other researches, he has never lost sight of 
the claims of these Western Islands. To gain further insight into 
their geological history he has made excursions to Auvergne, the 
Eifel country, Vesuvius, the Lipari Islands, and to Western America, 
and now at length, gathering up the results of this long-continued 
research, he has presented them to the Royal Society of Edinburgh 
as the memoir on the “History of Volcanic Activity during the Tertiary 
