John MacCulloch is famous for his pioneering work on Scottish geology producing the first geological map of the country.
Descended from the MacCullochs of Nether Ardwell in Galloway John MacCulloch was born in Guernsey on 6th October 1773. In his early adult years he studied medicine at Edinburgh where he qualified as M.D. in 1793 whereupon he entered the army as assistant surgeon. Attaching himself to the Artillery he became chemist to the Board of Ordnance. He still continued, however, to practise for a time as a physician.
In 1811 he communicated his first papers to the Geological Society.They were devoted to an elucidation of the geological structure of Guernsey and of Heligoland. This work probably led to his being selected in the same year to make some geological and mineralogical investigations in Scotland. He was asked to report on the suitability of Scottish mountains for a repetition of the pendulum experiments previously conducted by Maskelyne at Schiehallion. In the course of the explorations necessary for the purposes of these reports, he made extensive observations on the geology and mineralogy of Scotland. He also produced a collection of Scottish rocks and minerals which he presented to the Geological Society in 1814. In that year he was appointed geologist to the Trigonometrical Survey; and in 1816-1817 he was President of the Geological Society.
Although the fundamental principles of geology had been formulated and published by James Hutton, little investigation had taken place on the detailed geology of Scotland up until the time of MacCulloch. With passion MacCulloch set about investigating Scotland’s geology. One of his most important labours was the examination of the islands along the west coast at that time not easily visited, and presenting many obstacles to a scientific explorer. The results of this survey appeared (1819) in his two volume work Description of the Western Islands of Scotland, including the Isle of Man, which forms one of the classical treatises on British geology. He was elected Fellow of the Royal Society in 1820. He continued to write papers, chiefly on the rocks and minerals of Scotland, compiling such an amount of information that persuaded the Government to employ him in 1826 to prepare a geological map of Scotland. From that date up to the time of his death he returned each summer to Scotland and traversed every district inserting the geological features upon the then state-of-the-art topographic base map of Samuel Arrowsmith. He completed the field work in 1832, and in 1834 his map and an accompanying memoir were ready for publication. However, he died on 21st August 1835 following an accident on his honeymoon, and both the map and memoir were published posthumously in 1836.
Today, John MacCulloch’s geological map of Scotland hangs in the stairwell of the Geological Society I London, a fitting reminder of his pioneering work and place in the history of British geology. For most people MacCulloch’s name will forever be associated with a fossil tree he discovered at Burgh on the west coast of Mull.
Some of MacCulloch’s other works:
A Geological Classification of Rocks with Descriptive Synopses of the Species and Varieties, comprising the Elements of Practical Geology (1821)
The Highlands and Western Isles of Scotland, in a series of letters to Sir Walter Scott (4 vols. 1824)
A System of Geology, with a Theory of the Earth and an Examination of its Connection with the Sacred Records (2 vols. 1831)