The population of Salto is slightly in excess of twenty thousand, and, like every other town along the length of the stream, it serves as a storehouse for the pastoral and agricultural industries of the district. In many respects, however, the situation of the town gives it a commercial scope greater than that of the more southern towns. Although the climate lacks sufficient heat for the production of the banana and similar sub-tropical growths, the variety of fruit is very great. The orange flourishes in exceptional abundance here, and its cultivation forms a valuable addition to the wealth of the district. [Illustration: CATTLE ON THE ROAD.] [Illustration: A CORNER OF THE FRAY BENTOS FACTORY. To face p. 234.] Pleasantly situated, with shaded plazas and avenues, and with the orchards, vineyards, orange-groves, and well-timbered country of its outskirts, Salto lies at the end--or, to be more accurate, the beginning--of the lower Uruguay. Just above the town a white foaming line stretches from bank to bank during the periods when the river is low. But these lower falls are navigable during a considerable portion of the year, and not until Salto Grande, at a point considerably higher up, is the permanent barrier to navigation reached. Between Salto itself and Concordia the river is plentifully strewn with rocks, and, although the channels are deep, it is necessary on this head for vessels to use considerable caution, more especially as the tide races fiercely just here. Indeed, the fluctuations of the stream at this point are very great, and account for the tremendously lofty wooden passenger pier that serves the town. It is in the neighbourhood of Salto that is found the curious water stone that is referred to elsewhere in this book. It is in this province too that exist the topaz and amethyst mines. The visitor, however, need not trouble his head to start out upon any expedition with the object of picking up any of these curiosities. The topaz and amethyst fields are well-defined private property, while the water-stone is as shy and elusive as a four-leaved clover at home. If in quest of these objects, it is wiser to restrict the field of adventure to the Salto shops. It has been noticeable all the time whilst ascending the river that the water has steadily become less tinged with yellow. Above the falls, however, the distinction is far more marked. The stream here is peculiarly limpid, and the effect at a northern spot such as Santa Rosa, almost on the Brazilian frontier, is entrancing. Here the river is at times of a brilliant blue tint--a broad azure ribbon winding between swelling banks covered now with dense folds of vegetation. Viewed from the rising ground in the neighbourhood, the conviction is inevitable that, although the northern waters may have lost a little in commercial importance, the Upper Uruguay can lay claim to a degree of beauty with which the lower reaches, for all their charm, cannot compete. CHAPTER XX