1911 Encyclopædia Britannica, Volume 16… (1911)
“ Geology came to absorb all his leisure time, and he commenced to investigate the Silurian rocks of the Southern Uplands, and to study the graptolites and other fossils which mark horizons in the great series of Lower Palaeozoic rocks. His first paper on the Lower Silurian rocks of Galashiels was published in 1870, and from that date onwards he continued to enrich our knowledge of the southern uplands of Scotland until the publication by the Geological Society of his masterly papers on The Moffat Series (1878) and The Girvan Succession (1882) . ”
