NATURE 



217 



SCIENTIFIC WORTHIES, 

 XXVI 11.— Sir Archibald Geikie. 



SOME MONTHS ago the British Association for the 

 Advancement of Science was holding its annual 

 meeting at Edmburgh under the presidency of Sir Archi- 

 bald Geikie, F.R.S., Director- General of the Geological 

 Survey of the United Kingdom. 



It may well be said that a more appropriate choice 

 could hardly have been made by the Council of the 

 learned Association. Not only is Sir Archibald a 

 thorough Scot, born and educated in Scotland, where 

 he fulfilled for many years the most important duties as 

 a member of the geological staff, and later as a professor 

 in the University of Edinburgh, but, having long been 

 engaged in the supervision of the Scottish Survey, he 

 mapped with his own hand many hundreds of square 

 miles of country, and through the entire scenery of Scot- 

 land there is not a single point with the peculiarities of 

 which he did not make himself thoroughly familiar. His 

 knowledge of the ground is not at all restricted to geo- 

 logical relations. In Sir Archibald the qualities of the 

 geologist are combmed with those of the enthusiastic 

 lover of landscape, and his able pencil excels in drawing 

 original sketches in which the outlines, peculiar shades, 

 and, one might say, the general spirit of the scenery are 

 fixed with the most striking accuracy. Obviously, there- 

 fore, he was the right man to be placed at the head of the 

 Edinburgh meeting, which many prominent foreign in- 

 vestigators attended in the hope of afterwards travelling, 

 both as tourists and as men of science, through the most 

 interesting fields of the Highlands. Nobody could have 

 been better fitted to introduce them to the countr}'. When 

 putting Sir Archibald in the chair at Edinburgh, the 

 British Association not only did due justice to one of the 

 most distinguished sons of " mcdern Athens," it also 

 took the best course to secure from foreign guests the 

 fullest recognition of the various merits of Scotland. 



Sir Archibald Geikie was born at Edinburgh in 1838. 

 We learn from a notice in the Mining Journal that he 

 was educated at the Royal High School and at the Edm- 

 burgh University. When he was only twenty years old 

 he became an assistant on the Geological Survey for 

 Scotland, and proved so able that in 1867, when the 

 Scottish branch of the Survey was made a separate es- 

 tablishment. Sir Roderick Murchison deemed he could 

 not do better than confer the directorial powers on the 

 young assistant whom he had appreciated at work. Four 

 years later, the chair of Geology and Mineralogy at the 

 University having been founded by Sir Roderick with a 

 concurrent endowment by the Crown, Archibald Geikie 

 was invested with the new professorship, which he resigned 

 only at the beginning of 1881, when he was appointed to 

 succeed Sir Andrew C. Ramsay as Director-General of 

 the Geological Survey of the United Kingdom, and 

 Director of the Museum of Practical Geology in Jermyn 

 Street. 



That the new Director had not disappointed the hopes 

 ihe had excite. I, appeared with sufficient clearness when, 

 NO. 1210, VOL. 47] 



some time ago, the Queen conferred on him the honour of 

 knighthood. Now it is our duty to note the chief features 

 of his activity, and to state what personal part Sir Archi- 

 bald Geikie has played in the recent progress of science. 

 It is scarcely necessary to say that his geological achieve- 

 ments are too important to be conveniently reviewed in a 

 few lines. Nevertheless we shall try to give a general 

 idea of the prominent results to which his name must be 

 attached. 



Early appointed, as he was, as an officer of Scotland's 

 Survey, he had, from the beginning, to deal with the 

 most puzzling problems involved in the stratigraphy of 

 the Highlands. The case was a very difficult one, and 

 gave rise to much controversy between Sir Roderick 

 Murchison and many other geologists, among whom it will 

 be sufficient to quote the respected name of Nicol. As in 

 the Highlands gneisses and ordinary crystalline schists 

 were seen resting, with apparent conformity, on Silurian 

 strata, it had been admitted by Murchison that the 

 sequence was a normal one. Therefore the crystalline 

 schists had to be regarded, in spite of their Archaean 

 appearance, as metamorphosed Silurian deposits. Such 

 an assumption had a considerable bearing on other 

 geological problems, as it rendered highly probable the 

 theory that the so-called primitive gneisses were altered 

 sediments, and had nothing to do with the early crust of 

 the molten globe. 



That Sir Archibald should at first have taken his 

 Director's side is not at all surprising. But he was never 

 quite satisfied ; and his love of truth led him, as soon as 

 he was in a position to do so, to undertake a detailed re- 

 view of the facts. Since the discovery of Silurian fossils 

 in the rocks of N.W. Sutherland, it had been recog- 

 nized that the key to the structure of the Scottish High- 

 lands was to be searched for in that re^jion. Accordingly, 

 in the years 1^83 and 1884, MM. Peach and Home were 

 entrusted with a careful study of the Durness and EriboU 

 districts. They were very far from being directed to 

 obtain means of justifying the old survey. " It was a 

 special injunction to the officers " (we quote Geikie's own 

 words) " to divest themselves of any prepossession in 

 favour of published views, and to map the actual facts in 

 entire disregard of theory." 



From the work ably carried on by the distinguished 

 surveyors, and verified on the spot by the Director- 

 General, it appeared clearly that Murchison had been 

 deceived by prodigious terrestrial disturbances, of which, 

 at the time, nobody could have formed an idea. Over 

 immense reversed faults, termed thrust planes by Geikie 

 and his officers, the older rocks on the upthrow side had 

 been, as it were, pushed horizontally forward, covering 

 much younger sediments ; and the displacement attained 

 the almost incredible distance of more than ten miles. 

 Sometimes an outlier of the displaced ground was found 

 capping a hill, while the remainder had been swept away 

 by erosion, and the strangeness of the case led the observer 

 to write, " One almost refuses to believe that the little 

 outlier at the summit does not lie normally on the rocks 

 below it, but on a nearly horizontal fault." 



Disturbances of that kind had already been noticed in 

 some coal-basins, as, for example, on the southern limit 

 of the French and Belgian coal-field, where similar 

 outliers had been termed by M. Gosselet " lambeaux de 



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