India, July 27 -- The Chinese empire takes its first steps towards lighter, more representative money by issuing tokens or promissory notes on leather. In Sichuan, as trade booms, strings of coins are becoming too bulky to haul around, so black-and-red mulberry-paper receipts begin to be used instead. Sixteen merchants are awarded the right to issue these, and the government ultimately takes over, issuing the world's first fixed-denomination banknotes. They are essentially backed by bullion; a trader needed to hand over strings of coins and take an equivalent note in return. These notes could then circulate until someone returned to the merchant-banker to claim the corresponding coins. Of course, soon enough the notes are doing the rounds w...