The Danube, which is practically navigable from the town of Regensburg, 281 miles westward of Vienna, and the Black Sea, is the chief important waterway of Austria. Communication is obtained with Prussia by the Danube-Oder canal, and it is now proposed to establish a communication between this canal and the Elbe, in which case, traffic could be carried from Vienna to Hamburg by water all the way. It has been suggested to have communication made between the Danube and the Rhine either by Dilligen, 31 miles below Ulm, _viâ_ Königsbronn, 1640 feet above sea-level, to the Neckar, and from Cannstadt to Mannheim, and alternatively by Kehlheim, Nuremburg, and Bamberg, an ascent of 1375 feet to the Main, whence Mayence would be reached _viâ_ Frankfort. _The Oder and the Elbe Canal._—At an early period in the history of European trade, the desirability of having the Oder and the Elbe connected by an artificial waterway was discussed. This was even more of a desideratum about a century and a half ago than it is to-day. At that time, Stettin, which is built on the west side of the Oder, about 46 miles from its mouth, was perhaps the leading commercial city in Germany, having a large trade with England, France, and other countries on the west, with Scandinavia, and with the Baltic countries. The importance of joining such a port with Berlin, Hamburg, Dresden, and with other cities either upon or near to the Elbe, was manifest. The first canal built for this purpose was that of Plaven, completed in 1745. This canal joined the Havel with the Elbe at Parcy. It is about twenty English miles in length, 40 to 50 feet in width, and has three sluices. It reduces by more than one half the length of the navigation between the Oder and the Elbe. About the same time the canal of Finow was constructed to connect the same rivers by the Finow and the Havel. There are thirteen sluices on this canal. Another canal, called the Frederick William, joins the Oder and the Spree above Frankfort, and, uniting with the Havel near Brandenburg, connects the latter with the Elbe. It is fifteen English miles long, and has ten sluices.