Background

Ethnicity: MacCulloch was descended from a Scottish family, the MacCullochs of Ardwell, Galloway.

MacCulloch was born on October 6, 1773, in Guernsey, United Kingdom, the third of eight children of James MacCulloch, a wine merchant of Roscoff, and his wife, Elizabeth de Lisle, a daughter of Thomas de Lisle, a Guernsey jurat.

Education

MacCulloch entered Edinburgh University to study medicine and graduated a Doctor of Medicine in 1793. His interest in geology arose during his stay in Edinburgh, possibly because he attended the lectures of John Walker, professor of natural history, who included geology and mineralogy in his course.

Career

MacCulloch's first appointment was as assistant surgeon to the Royal Regiment of Artillery, a branch of the army controlled by the Master General and Board of Ordnance. In 1803 he was appointed chemist to the Board of Ordnance. From 1807 he also practiced at Blackheath, near London. He became a member of the newly-formed Geological Society of London in 1808 and its president in 1816. In 1811 he gave up his medical practice and thereafter was employed by the Board of Ordnance in tasks requiring knowledge of geology. He spent the summers of 1811 to 1813 in Scotland, investigating what rocks could be used safely in mills for grinding gunpowder. In 1814 the Board of Ordnance appointed him geologist to the Trigonometrical Survey then being carried out in Scotland. This involved two tasks. One was to choose sites geologically suitable for setting up the zenith sector used to determine the meridians; the other was to select a mountain geologically suitable for determining the earth's density.

While engaged in this work MacCulloch used his spare time to record additional geological information with the intention of constructing ultimately a geological map of the whole of Scotland; and he tried to persuade his employers that official support for the preparation of such a map would be in the national interest. His employment in Scotland was terminated in 1820. During this period MacCulloch also lectured in chemistry during the winter at the Royal Military Academy at Woolwich and later held a similar post at the East India Company's College at Addiscombe, where he also taught geology. He was elected a fellow of the Royal Society in 1820. In the next few years, MacCulloch spent some time in completing for the Board of Ordnance reports on the work he had carried out in Scotland. In 1826 his post as a chemist was abolished. He was then informed that for the purpose of completing a geological map of Scotland he could transfer his services to the Treasury, which would pay him a salary and expenses.

From 1826 until about 1832 MacCulloch visited Scotland every summer to complete his geological survey. The question of whether his geological map should be published caused some delay, but eventually the Treasury sanctioned publication. MacCulloch died as a result of a carriage accident in 1835; the map was published, posthumously, in 1836.

MacCulloch was the author of a large number of books and papers of geological, mineralogical, and chemical interest. Contemptuous of stratigraphical paleontologists, MacCulloch once described them as "namby pamby cockleologistso and formation men." Nevertheless, in A Description of the Western Isles of Scotland (1819), he recorded the occurrence of Jurassic fossils in the islands of Skye and Raasay and remarked on their similarity to those found in Jurassic rocks in Somerset and Gloucestershire in England. MacCulloch also found for the first time organic remains (Serpulites maccullochii) in the Cambrian quartzite in the northwest highlands of Scotland. Though he did not recognize the significance of this discovery, it later proved of great importance in working out the complicated overthrust rock succession in this area. His Description of the Western Isles of Scotland was MacCulloch's most important book. The numerous islands described, large and small, many of which hadnot previously been examined by geologists, contain rocks ranging in age from Precambrian to Tertiary, including many igneous rocks. His descriptions of the igneous rocks and the sketches and maps in the accompanying atlas promoted a true understanding of the nature and origin of igneous rocks at a time when the mistaken views of Werner on their origin.

MacCulloch's geological map of Scotland, on a scale of four miles to the inch, was the first large-scale geological map of the country. It differentiated eighteen rock types and was largely, if not entirely, based on his own observations. It as a remarkable achievement for one man, especially considering the difficulties of access to the remoter parts of the country and the inaccuracies of the only topographical map available. Though gradually superseded by other maps

during the nineteenth century, some of the areas he described had still not received detailed examination even as late as the mid-twentieth century. MacCulloch's observations greatly advanced general knowledge of the varied rock formations in Scotland, especially that of the igneous rocks. Though his work is now largely forgotten, it was appreciated in his time by Lyell, who made several references to it in both his Principles of Geology and his Elements of Geology.

Achievements

• MacCulloch's most important work was that carried out in Scotland. Here his knowledge of mineralogy and chemistry proved invaluable in studying the igneous and metamorphic rocks, which occur over about three-quarters of the country. He was an acute observer of geological phenomena, and the value of his published work was often enhanced by his careful sketches of the field relations between the different types of rock.

Works

More photos

• book

  • A Description of the Western Islands of Scotland, Including the Isle of Man: Comprising an Account of Their Geological Structure; With Remarks on the Agriculture, Scenery and Antiquities

    (Volume 1)

  • 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 1824
  • A System of Geology, with a Theory of the Earth and an Examination of its Connection with the Sacred Records 1831
  • Proofs and Illustrations of the Attributes of God, from the Facts and Laws of the Physical Universe: Being the Foundation of Natural and Revealed Religion 1837

Views

In some respects, MacCulloch was conservative in outlook. He was unwilling to accept new geological ideas unless supported by evidence acceptable to him. He examined the lithological and mineralogical characteristics of the sediments carefully and accepted that their contained fossils yielded information about the physical conditions existing at the time they were formed. He believed, however, that contemporaneous knowledge of fossil forms and their distribution was inadequate. He felt that their use as stratigraphical indexes and for correlation was unreliable and likely to cause confusion, even though by about 1820 they were quite widely used for this purpose.

MacCulloch's "theory of the earth" was largely Huttonian in concept, modified by the suggestion - perhaps derived from Cuvier - that a succession of revolutions might have brought about the extinction of some forms of life. An unusual feature of the work is the inclusion, in an appendix, of advice on the qualifications required of a geologist; on describing geological observations; on the instruments required; and on constructing geological maps. Much of this information is still useful.

Membership

• Geological Society of London , United Kingdom

  1808

• Royal Society of London , United Kingdom

  1820

Personality

Quotes from others about the person

• In an obituary notice, Lyell recorded "that as an original observer MacCulloch yields to no other geologist of our time, and he is perhaps unrivaled in the wide range of subjects on which he displayed great talent and profound knowledge," and he added that he had "received more instruction from his labors in geology than from those of any living writer."

Connections

MacCulloch married Louisa Margaretta White in 1835.

Father:

James MacCulloch

Mother:

Elizabeth de Lisle

Spouse:

Louisa Margaretta White

References

• Dictionary of Scientific Biography Volume 7
  1973