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　　Such drafts were used for giro systems of banking as early as Ptolemaic Egypt in the first century BC.

　　Jiaozi （Song Dynasty）， the world's earliest paper money.

　　However the use of paper money as a circulating medium is intimately related to shortages of metal for coins. In the 600s there were local issues of paper currency in China and by 960 the Song Dynasty， short of copper for striking coins， issued the first generally circulating notes. A note is a promise to redeem later for some other object of value， usually specie. The issue of credit notes is often for a limited duration， and at some discount to the promised amount later. The original notes were restricted in area and duration， but the Yuan Dynasty， facing massive shortages of specie to fund their occupation of China， began printing paper money without restrictions on duration. By 1455， in an effort to rein in economic expansion and end hyperinflation， the new Ming Dynasty ended paper money， and closed much of Chinese trade.

　　In Europe the first banknotes were issued by Stockholms Banco， a predecessor of the Bank of Sweden， in 1660， although the bank ran out of coins to redeem its notes in 1664 and ceased operating in that year. It was in the early 1690's when the Massachusetts Bay Colony issued the first permanently circulating banknotes. The use of fixed denominations and printed banknotes came into use in the 18th century.

　　The first polymer banknote， the 1988 Australian $10 note

　　The ease with which paper money can be created， by both legitimate authorities and counterfeiters， has led both to a temptation in times of crisis such as war or revolution to produce paper money which was not supported by precious metal or other goods， thus leading to hyperinflation and a loss of faith in the value of paper money， e.g. the Continental Currency produced by the Continental Congress during the American Revolution， the Assignats produced during the French Revolution， the paper currency produced by the Confederate States of America， the financing of the First World War by the Central Powers （by 1922 1 gold Austro-Hungarian krone of 1914 was worth 14，400 paper Kronen）， the devaluation of the Yugoslav Dinar in the 1990s， etc. Banknotes may also be overprinted to reflect political changes that occur faster than new currency can be printed.

　　Most banknotes are made of heavy paper， sometimes mixed with linen， cotton， or other textile fibres. Generally， the paper used is different from ordinary paper： it is much more resilient， resists wear and tear， and also does not contain the usual agents that make ordinary paper glow slightly under ultraviolet light.

　　The first kinegram banknote， the 1988 Austrian 5000 Schilling note （Mozart）

　　In 1988， Australia produced the first polymer banknote， made from biaxially-oriented polypropylene （plastic）， and in 1996 became the first country to have a full set of circulating polymer banknotes. Since then， other countries to adopt polymer banknotes include New Zealand， Romania， Brazil and Mexico， with many others issuing commemorative polymer notes. Polymer banknotes were developed to improve durability and prevent counterfeiting through incorporated security features， such as optically variable devices that are extremely difficult to reproduce.

　　In 1988， Austria produced the 5000 Schilling banknote （Mozart）， which is the first foil application （Kinegram？） to a paper bank note in the history of bank note printing. The application of optical features is now in common use throughout the world.

　　地图发展史

　　ES 551 —— James S. Aber

　　What is a Map？

　　A map is a graphic representation or scale model of spatial concepts. It is a means for conveying geographic information. Maps are a universal medium for communication， easily understood and appreciated by most people， regardless of language or culture. Incorporated in a map is the understanding that it is a "snapshot" of an idea， a single picture， a selection of concepts from a constantly changing database of geographic information （Merriam 1996）。

　　Old maps provide much information about what was known in times past， as well as the philosophy and cultural basis of the map， which were often much different from modern cartography. Maps are one means by which scientists distribute their ideas and pass them on to future generations （Merriam 1996）。

　　Early Maps

　　Cartography is the art and science of making maps. The oldest known maps are preserved on Babylonian clay tablets from about 2300 B.C. Cartography was considerably advanced in ancient Greece. The concept of a spherical Earth was well known among Greek philosophers by the time of Aristotle （ca. 350 B.C.） and has been accepted by all geographers since. Greek and Roman cartography reached a culmination with Claudius Ptolemaeus （Ptolemy， about A.D. 85-165）。 His "world map" depicted the Old World from about 60°N to 30°N latitudes. He wrote a monumental work， Guide to Geography （Geographike hyphygesis）， which remained an authorative reference on world geography until the Renaissance.

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