Edward Anthony Jenner, (1749 –1823) was an English physician and scientist from Berkeley, Gloucestershire, who was the pioneer of smallpox vaccine. He is often called "the father of immunology", and his work is said to have "saved more lives than the work of any other man".
Dr Stephen Maturin, the ship's surgeon in Patrick O'Brian's Master & Commander series is, to my mind, one of the best doctors in fiction ever created. The character is imbued with the author's deep knowledge of Sir Joseph Banks while instilled with knowledge gleaned from diaries of ship's surgeons. The diaries are held in the Greenwich Library.