The semi-arid regions can only support a reasonable population under conditions of the strictest economy and wisdom in the use of the water supply, and in addition to their other economic uses the forests are indispensably necessary for the preservation of the water supply and for rendering possible its useful distribution throughout the proper seasons.

While going through these mountains last summer and reflecting upon the prodigious changes which the sheep have brought about in a few years, it occurred to me that we must look to Oriental countries in order to see the final results of sheep and goat grazing in semi-arid climates.

I venture the prediction that the sheep industry on naturally semi-arid lands is doomed; that the future feeding of both sheep and cattle will be on irrigated lands, and that the forests will be carefully guarded by State and Nature as natural reservoirs.

Our route led us out of the Chuquibamba Valley by a long, hard climb up the steep cliffs at its head and then over the gently sloping, semi-arid desert in a northerly direction, around the west flanks of Coropuna.

The uncultivated spots were covered with cacti, thorn bushes, and the gnarled, stunted trees of a semi-arid region.

Here again the statistics require interpretation, for in the spread of the frontier the addition of large farms in the arid and semi-arid regions may raise the average, or the breaking up of large plantations in the South may decrease the average, without this indicating any essential change in the technical conditions of farming in the country generally.