The ridge of hills is a most important feature in the geology of this desert region.[[2]] It is to be traced from Cutch Bhuj, strongly or faintly marked, according to the nature of the country. Sometimes it assumes, as at Chhotan, the character of a mountain; then dwindles into an insignificant ridge scarcely discernible, and often serves as a bulwark for the drifting sands, which cover and render it difficult to trace it at all. As it reaches the Jaisalmer country it is more developed; and at the capital, erected on a peak about two hundred and fifty feet high, its presence is more distinct, and its character defined. The capital of the Bhattis appears as the nucleus of a series of ridges, which diverge from it in all directions for the space of fifteen miles. One branch terminates at Ramgarh, thirty-five miles north-west of Jaisalmer; another branch extends easterly to Pokaran (in Jodhpur), and thence, in a north-east direction, to Phalodi; from whence, at intervals, it is traceable to Gariala, nearly fifty miles due north. It is a yellow-coloured sandstone, in which ochre is abundantly found, with which the people daub their houses.
These barren ridges, and the lofty undulating tibas of sand, are the only objects which diversify the almost uniform sterility of these regions. No trees interpose their verdant foliage to relieve the eye, or shelter the exhausted frame of the traveller. It is nearly a boundless waste, varied only by a few stunted shrubs of the acacia or mimosa family, some succulent plants, or prickly grasses, as the bharut[[3]] or burr, which clings to his garment and increases his miseries. Yet compared with the more northern portion, where “a sea of sand without a sign of vegetation”[[4]] forms the prospect, the vicinity of the capital is a paradise.
There is not a running stream throughout Jaisalmer; but there are many temporary lakes or salt-marshes, termed sar, formed by the collection of waters from the sand-hills, which are easily dammed in to prevent escape. They are ephemeral, seldom lasting but a few months; though after a very severe monsoon they have been known to remain throughout the year. One of these, called the Kanod Sar, extends from Kanod[[5]] to Mohangarh, covering a space of eighteen miles, and in which some water remains throughout the year. When it overflows, a small stream issues from the Sar, and pursues an easterly direction for thirty miles before it is absorbed; its existence [281] depends on the parent lake. The salt which it produces is the property of the crown, and adds something to the revenue.