98 THE DOWNFALL OF THE DERVISHES or a whisky and Rosbach, are common beverages in the evening. It is often very difficult indeed—especially when one is on the march—to keep such luxuries cool, but the ingenious “‘sparklets,” which were brought out to the Sudan in thousands, will always, if fairly good water can be got, provide one with a decent drink, as the sudden liberation of the compressed gas cools the water as well as aérates it.

It is worth while being really thirsty and hungry to understand the pleasures of drink and food. Our English meals follow each other with such regularity and diversity that one seldom realises what it means to crave for food and drink as a primary instinct. But oh! the joy of a deep draught of cool water after long hours of abstention in the desert, or, what is almost as bad, a long course of brackish water—saline water, which quenches one’s thirst for the moment only to increase it by the after-taste. Once when I was travelling with Mr. Bent, I remember how I was walking in a stony ravine after six days of nothing but brackish water; suddenly, to one’s delighted vision, a little brook of limpid water appeared