Bonney, T.G. (Thomas George), 1833-1923

Thomas George Bonney was born 27th July in Rugeley, the eldest of 10 children born to Reverend Thomas Bonney, master of Rugeley Grammar School, and his wife Eliza Ellen, daughter of Edward Smith of Rugeley. At the age of 14 he attended Uppingham School, where he was head boy, before attending St Johns College, where he graduated as Twelfth wrangler in the Mathematical Tripos in 1856 and obtained a second class in the classical tripos. Illness prevented him from sitting for the theological Tripos as well.

After a period of ill-health and recovery spent in the Alps, Bonney taught at Westminster School in 1857 teaching mathematics. During this time he was ordained deacon in 1857 and priest the following year. He was then elected to a fellowship of St Johns College, Cambridge becoming a tutor in 1868.

Whilst he attended some of Adams lectures, he never studied geology formally. He started teaching the subject in 1869, taking further responsibility when Sedgwick was in his later years. He was not elected to success Sedgwick however.

He learned and taught the techniques of preparing rocks in thin sections and examining them microscopically. He was particularly interested in the igneous and metamorphic rocks in Alpine regions and the Lizard in Cornwall, Salcome, and Charnwood Forest, Wales and the Scottish highlands. He contented the German tradition of linking rock types with age, and regarded the rocks in Charnwood as Precambrian, whereas they had been mapped by the Geological Survey as Cambrian.

In 1877 Bonney accepted the Yates-Goldschmidt Professor of Geology at University College, London although remained in Cambridge until 1881. He became secretary of the British Association for the Advancement of Science and subsequently moved to London to set up home with his sister in Hampstead. He wrote regularly for The Standard until 1905, when he returned to Cambridge to resume his connections with St Johns.

Bonneys interest in Glaciology was life-long and he was a considerable Alpine climber. Both his second paper to the Geological Magazine and his presidential address to the British Association in 1910 dealt with the subject.

He emphasized the importance of fitting observations and theory, and his many visits to Switzerland caused him to dispute the efficacy of ice as an erosive agent that could gouge out rock basins and create lakes, and he remained unconvinced of the formation of cirques by plucking action or of more than superficial modification of river valleys by moving ice. His theory was derived largely from the earlier suggestions of Charles Lyall that glacial markings could be attributed to the rasping action of floating icebergs.

Bonney was a preacher at the Chapel Royal, Whitehall 1877-1878, gave the Boyle lectures in 1890 and 1891, was Hulsean lecturer for 1884, Rede lecturer in 1892, and honorary canon of Manchester.

Bonney joined the Geological Society in 1860 of which he became Secretary and later President. He was awarded the Wollaston Medal in 1889. He was also President of the Mineralogical Society (1884-6), the Alpine Club (1883), of section C of the British Association (1886). He was elected FRS in 1878 and served on the Societys council on three occasions, and was vice-president from 1898-1899. He held honorary degrees from Dublin, Sheffield and Montreal.

Bonney died 10th December 1923. He was unmarried. He wrote his autobiography Memories of a Long Life which was published in 1921, although it says little about his geological work.