LOFTUS TURKO-PERSIAN FRONTIER. 303 



force in the more northerly basin, at regular intervals, but in the 

 other irregularly, at intervals of five or seven seconds, gurgling from 

 belovs', and throwing up a strong jet to the height of a foot above the 

 surface. The temperature of the two springs is the same, viz. 96° 

 Fahr., indicating a common origin. The water is strongly nitrous 

 and chalybeate. As the surface of the water cools, numerous thhi 

 lamellae of cream-coloured carbonate of lime are formed, and float 

 about like scum. These lamellae are sometimes two inches long, and 

 about the thickness of a wafer ; the upper surface is smooth and 

 shining, as if strongly glazed, and the under surface frequently shows 

 its crystallized structure. They are carried along by the water as it 

 flows from the basins, and form a thin coating upon the surface of 

 the rapidly forming travertin. Under the feet these lamellae crackle 

 and break like thin " cat-ice." 



As the water flows onwards, cooling in its passage, it deposits its 

 heavier calcareous matter in small granules of cream-coloured car- 

 bonate of lime, which become cemented together by the continual in- 

 filtration of the water through them, and at length are sufliciently 

 compact to be called travertin. In passing over and among these 

 forming granules, the water is soaked up as if by a sponge, and hence 

 it has frequently been described by travellers as becoming petrified on 

 the spot ! 



The process of deposition of the calcareous particles is without 

 doubt exceedingly rapid ; but not sufliciently so to be observed 

 instantaneously. 



Sometimes the calcareous matter is deposited in thin concentric 

 circles (the exterior one frequently a quarter of an inch in diameter), 

 granulated on the surface. The great body of the water, however, 

 passes over the curved mass of the travertin into the ravine below, in- 

 creasing the bulk with additional layers. The travertin assumes the 

 stalactitic form when the water flows over some pendent plant or 

 other body ; in such cases a rippled and honeycombed aspect is 

 produced. From the hot springs to the bottom of the ravine is a 

 depth of about 60 feet, — a solid mass of travertin ; while at three 

 times that height above the springs the older and altered deposit 

 rests on the slope of the felspathic rock. 



Other springs flow in small streams from holes in the travertin ; 

 they are less saline, and more strongly chalybeate, while the tempera- 

 ture does not exceed 90° or 92° Fahr. 



Above the village is the basin of an extinct spring. The hot 

 springs of Derik are much resorted to for every species of complaint 

 to which the Kourd is subject. 



It may be worth while to recur to the various changes which have 

 taken place since the deposition of the red sandstones and gravel 

 beds, which I assume to be of the same age as the similar beds 

 occurring near Dizful, and containing evidences of the existence of 

 feline animals, and therefore of comparatively modern formation. 

 We have : — 

 1 . The elevation of these beds from an horizontal into a vertical 



