Scurvy is now almost a forgotten disease, but it would be difficult to exaggerate its importance in the history of a maritime nation such as our own. To the historian of medical science it is equally interesting, because the various and extraordinary variety of theories concerning it reflect in themselves the intellectual climate of the past. By their repeated refusal to accept the conclusions of an experimental method, by their pedantic reliance on a priori reasoning or antiquated prejudices, the medical authorities of all countries delayed the conquest of this terrible disease long after a cure had been established by men who had practical experience of it. If anyone imagines that even in scientific knowledge progress is inevitable, let him remember that scurvy continued to be the curse of the sea and the hardship of explorers so recent as Scott and Shackleton a hundred years after it had been eliminated in the fleets of Nelson's day.