utmost was made of the sources from which water is drawn; no pains have been spared to extract every possible drop of water from the heart of the hills within a considerable distance, and to convey it undiminished by evaporation to the city.  This is done by underground channels called kanats, which are excavated with great ingenuity and skill, and are marvels of industry.  This system prevails all over Persia, and existence as well as the fertility of the soil mainly depends on the water-supply thus obtained.  The sandy expanse round Yezd in the desert of South-eastern Persia has been made literally to blossom like the rose by means of these subterranean channels, some of which are tunnelled for a distance of thirty miles.  I was there in spring-time, and was then able to see what a wonder-worker water is in Persia.

The pressing need of more water for Tehran has now drawn attention to the proposals of some years ago for increasing the supply.  One of these was to divert to the south an affluent of the Upper Lar, which rises in the Elburz range, and flows into the Caspian.  It was seen that this could be done by cutting a new channel and tunnelling from a point sufficiently high, where the stream runs in an elevated valley between the double ridge of the range.  The work would have been similar, but simpler, to what was completed last year in Madras, where the upper Periyar stream was changed from a western to an eastern flow.  The execution of the Lar project would be easy, and it would not practically affect the volume of water in the main stream, which receives many tributaries below the proposed point of piercing the watershed.  But the Lar Valley was one of the Shah’s summer retreats, and a favourite pasture-ground for his brood mares and young stock.  It is, moreover, a popular resort of flock-owning nomads, and as the Shah’s love of camp life there led him to fear injury to the grassy plains and slopes of his favourite highlands, the project was abandoned.

There was another scheme to construct a series of reservoirs by means of strong barriers at the foot of the lower ravines of the Elburz range, eight miles north of Tehran, in which to keep the winter water which comes from the melting snow.  The whole mountain-chain is covered with snow each year from top to bottom.  In April and May the snow melts, and the precious water flows away where it is not wanted.  Were this water stored, it would be made available in the succeeding hot months.  The sloping plain between the hills and the town is capable, with irrigation, of great fertility, and the construction of these reservoirs would prove a veritable gold-mine.