http://www.npg.org.uk/collections/search/portrait/mw40351/Adam-Sedgwick?
Adam Sedgwick by Samuel Cousins, after Thomas Phillips mezzotint, published 1833, NPG D5929Adam Sedgwick by Samuel Cousins, after Thomas Phillips mezzotint, published 1833, NPG D5929
© National Portrait Gallery, London
Darwin used letter-writing to establish networks of collectors, informers, and what was in effect a virtual thinktank. His correspondents, many of whom he never met, were his research assistants, his critics and his scientific colleagues. The other side of the coin is that they used him as a patron and a source of authority. And as a result, his correspondence allows us not only to study his scientific methods and the development of his ideas but to look much more widely at the practice of science by a very broad range of people, and to look at them both individually and collectively.