And herewith I will leave these lakes. It would be very interesting to visit them again in ten or twenty years' time and ascertain in which direction their development is tending, whether the river is minded to pour still greater quantities of water into the desert, or entirely to withhold from them its maintenance. One visit like mine is indeed sufficient to tell us what a country such as this is like, but only a second visit can supply data for deducing reliable conclusions regarding it. I have deliberately dwelt at length upon these lakes, because they contribute in a high degree to the understanding of several other problems in this same region, to wit the bajir depressions and their relief, the progress of the dunes, the river's caprices, and the continuous shrinkage of Kara-koschun.