Thomas Darwin was the last of eleven children born to Charles Robert Darwin and Emma Wedgwood. Scattered details of his early years can be found by focused reading of obvious sources — primarily the preserved correspondence of Emma Darwin (particularly the letters to her maiden Aunt Fanny Allen) as well as the affectionate but unpolished accounts of Charles Darwin’s life by various descendants. The writings of Charles Darwin also contain a number of references to his youngest son. These include his Autobiography as well as his text Expression of the Emotions in Man and Animals where descriptions of Thomas appear on three occasions. In what is likely a unique source for any life story, there are also the ‘scientific’ observations of Thomas contained within one of his father’s unpublished diaries.
Little preserved material relates to Thomas’s adolescence or early adulthood. There are the brief annual reports of his student experience at Clapham, a boarding school attended by other members of his family. Accounts of Thomas’s subsequent two years at Cambridge University are largely confined to the transcriptions of his readings to the Plinian Society, a student group devoted to discourse on the natural sciences, as well as a preserved expense notebook with its list of purchases incurred during Thomas’s brief research excursion to Sheffield. There is also Thomas’s single letter to his father, and his father’s response, both widely published in various compilations of Darwin correspondence. Finally, brief reminiscences of Thomas appear in an acquaintance’s personal memoir.
According to Darwin family legacy, an otherwise healthy Thomas tragically and abruptly died of tuberculosis while travelling in Canada following his second year at Cambridge. The expanded, and surprising life story of Thomas presented in The Evolution of Inanimate Objects emerges from a range of previously unappreciated collections of primary sources.