The Effect of Inflation on the Money Supply

Book transfers are when you and the person you're doing business with both have an account with the same banker. It's one of the things that allows you to speed up the velocity of money in later medieval Europe. There is not as much of a trade deficit between Europe and the East as there had been 50 or 60 years before. The effect that that has on the money supply, it's a question I'm not super familiar with.