The Ebro has its rise from the source, Fontibre, in the province of Santander, and takes a south-easterly course of 466 miles, through the provinces of Santander, Burgos, Navarre, and Aragon, almost parallel with the Pyrenees, till it falls into the Mediterranean, through a sandy delta stretching some fifteen miles into the sea below Amposta. The descent for the first 200 miles of its course is exceedingly rapid, but after that the fall is gradual till it reaches the sea. In its course it receives the waters of many tributaries, both on the left from the Pyrenees, and on the right from the Idubeda mountains and the sierras of Southern Aragon. Were it not for these tributaries little of its waters would reach the Mediterranean, so dry and arid are the Bardenas of Navarre, and the Dehesas of Aragon, through which it flows. The Spaniards have a proverb that it is the Navarrese and Aragonese streams--the Arga, the Ega, and the Aragon--which make a man of the Ebro. Farther down, the Gallego runs in near Saragossa; while the united waters of the Cinca and the Segre at Mequinenza pour a far larger volume of water into the parent bed than it contains itself. From the right, the principal streams are the Xalon, with its tributary the Xiloca, which joins the Ebro between Tudela and Saragossa, the Marten, and the Guadalope near Caspe. The Ebro, notwithstanding its length, the number of its tributaries, and the extent of its basin, 25,000 square miles, is of little use for navigation. A magnificent canal--first projected and commenced by the Emperor Charles V. (I. of Spain) then after a lapse of more than two centuries taken in hand by Charles III., in 1770--runs from Tudela to Saragossa; thence to the sea it still remains in project only. The part already finished is falling into decay; and it is only the excellent quality of the masonry, and of the cement or mortar employed, that retards its utter ruin. The traffic is very small; and even as a means of irrigation its waters are allowed greatly to run to waste. At the apex of the delta from Amposta to San Carlos de la Rapita a canal of eight miles has been cut for purposes of navigation; but the formation of a bar, and the silting up of the bay, have rendered it almost useless. The other rivers which flow into the Mediterranean, between the lower course of the Ebro and the Pyrenees are the Fluvia, which flows into the gulf of Rosas, the Ter, which passes by Gerona, and the Llobregat near Barcelona. All are torrential streams, unfit for navigation; but their waters, if all utilized for irrigation like those of the Llobregat, would be sources of immense wealth to the country.