Encounters with Charles Hartt, Louis Agassiz and the Diamonds of Bahia: The Geological Activities of the Reverend Charles Grenfell Nicolay in Brazil, 1858-1869

The Reverend Charles Grenfell Nicolay (1815-1897) made an important contribution to early geological work in Western Australia as a scientific adviser to the Colonial government and founder of the Colony's first public collection of rocks, minerals and fossils. During his early career he taught geography at King's and Queen's Colleges in London, before leaving London in 1858 to serve as the Anglican Church Chaplain to the British residents in the city of Salvador, Bahia, Brazil. We describe here some of his geological activities in Brazil over the period 1858-1869. He assisted Charles Frederick Hartt (1840-1878) and Louis Agassiz (1807-1873) on the Thayer Expedition of 1865-1866 in their geological investigations of the province of Bahia, most notably providing geological descriptions of the diamond deposits of the Chapada Diamantina, then a diamond province of world importance. After returning to England, he presented his findings on the Chapada Diamantina to the British Association for the Advancement of Science meeting in Norwich in 1868. From May to August 1869, he made a brief return visit to Brazil acting as a geological advisor to the Brazilian Turba Company, who were hoping to exploit bituminous sedimentary deposits adjacent to the Bahia de Camamu, Bahia, in the production of oil and gas. Following his arrival in Western Australia, he corresponded with the Reverend William B. Clarke (1798-1878), in 1871-1872, on the subject of Brazilian diamonds, as Clarke sought to understand the diamond occurrences in eastern Australia. Through Clarke, Nicolay's description of the geology of the Chapada Diamantina was circulated to the Australian scientific community.