James Geikie seems to have had no difficulty whatever in picking up the essentials of field geology. He was very diligent and had sufficient physical strength for his work. In time he became a great walker, thinking nothing of covering fifty miles in a day. The open-air life suited him perfectly. He had one of the gifts most valuable to a field-geologist, sometimes described as “an eye for the country,” the faculty of interpreting the geological meanings that underlie surface features. Although never a professed palæontologist he had a working knowledge of Carboniferous fossils, and he was always a keen and critical observer of rocks both in a fresh and in a weathered condition. His early maps, judged even by the standards of the present day, were astonishingly good, and always give the impression that he went thoroughly into the evidence so far as it was available. He was cautious and thorough, and as a result of this his maps show very few deletions due to changes of opinion as fuller information was acquired during the progress of his work. From the first he exhibited great ability as a draughtsman, and his maps and sections are not only very clear, well-proportioned, and pleasing to the eye, but show also an individuality which arose from natural gifts, and was not acquired by copying models. Although at that time geologists on the Survey were not moved about the country so frequently as is now the case, but settled down for several seasons in a well-defined area, James Geikie had no reason to complain of a lack of variety in the ground allotted to him. His early stations in Fife and Kinross included stratified and igneous rocks of Old Red Sandstone and of Carboniferous Age, and in Peeblesshire he made acquaintance with Silurian rocks, which at that time were still very imperfectly understood, and presented many difficult problems then unsolved. It was in Ayrshire, however, that his powers most fully displayed themselves, and the long period of field work in that county from 1865 to 1872 undoubtedly saw the development of his abilities as a field-geologist. In after years many of the best illustrations both of structural geology and of glacial geology that enlivened his books and his lectures were culled from the note-books in which he constantly recorded the results of his observations in that field. From his letters it seems that he disliked the coalfield geology, which necessitated the examination of mining plans, frequent attendance at colliery engineers’ offices, and great absorption in details which are of little general importance. But no one would have suspected this from his field maps, which, if we remember how rapidly his work was done, show much detail of underground structures taken from colliery plans.