Such a development of wealth in Venice and Genoa implies a large producing and consuming area behind them, able to take and pay for the costly products of India and China. Before the end of the thirteenth century the volume of European trade had swelled to great proportions. How full of historic and literary interest are the very names of the centres and leading routes of this trade as it was established in those days, with its outlook upon the Mediterranean and the distant East! Far up in the North we see Wisby, on the little isle of Gothland in the Baltic, giving its name to new rules of international law; and the merchants of the famous Hansa towns extending their operations as far as Novgorod in one direction, and in another to the Steelyard in London, where the pound of these honest "Easterlings" was adopted as the "sterling" unit of sound money. Fats and tallows, furs and wax from Russia, iron and copper from Sweden, strong hides and unrivalled wools from England, salt cod and herring (much needed on meagre church fast-days) from the North and Baltic seas, appropriately followed by generous casks of beer from Hamburg, were sent southward in exchange for fine cloths and tapestries, the products of the loom in Ghent and Bruges, in Ulm and Augsburg, with delicious vintages of the Rhine, supple chain armour from Milan, Austrian yew-wood for English long-bows, ivory and spices, pearls and silks from Italy and the Orient. Along the routes from Venice and Florence to Antwerp and Rotterdam we see the progress in wealth and refinement, in artistic and literary productiveness. We see the early schools of music and painting in Italy meet with prompt response in Flanders; in the many-gabled streets of Nuremberg we hear the voice of the Meistersinger, and under the low oaken roof of a Canterbury inn we listen to joyous if sometimes naughty tales erst told in pleasant groves outside of fever-stricken Florence. [Sidenote: Effects of the Mongol conquests.] [Sidenote: Cathay.] [Sidenote: Carpini and Rubruquis.] [Sidenote: First knowledge of an eastern ocean beyond Cathay.]