William Hewson (1739-74): the father of haematology.

William Hewson has been called the father of haematology. Initially working alongside the Hunter brothers in London in the mid-18th century, he advanced our knowledge of red and white cells (but mistakenly thought some red cells started as white cells and could not recognise different varieties of white corpuscles), showed that it was fibrinogen and not the cells that led to coagulation, greatly advanced our knowledge of the lymphatic system in humans, fishes and amphibians, explored the functions of the thymus and spleen and, investigated pneumothorax and surgical emphysema. His life, cut short at 35 years, was often intertwined with those of the Hunters, Alexander Monro secundus and Benjamin Franklin. This paper reviews his work, his relationships and his impact on a nascent science.