How we lost the cure for scurvy

Recently I have been re-reading one of my favorite books, The Worst Journey in the World, an account of Robert Falcon Scott's 1911 expedition to the South Pole. I can’t do the book justice in a summary, other than recommend that you drop everything and read it, but there is one detail that particularly baffled me the first time through, and that I resolved to understand better once I could stand to put the book down long enough.