218 Copt. Hutton's Geological Report. [No. 111. 



their original sites, where combining with other soils, they would form 

 strata peculiar to those situations. 



It is probable that these sudden overwhelmings of the district now call- 

 ed Kunawur, may have happened more than once, both from this and from 

 other lakes ; for although the Spiti lake had burst through its rocky bar- 

 riers and found an outlet for the superabundant waters, it would merely 

 have expended itself to a level with the opening it had made, at which 

 point it would again remain until the accumulating supplies from the 

 snow-clad peaks above, and the never-ceasing flow and action of the 

 waters upon the already ruptured rocks, should again have brought 

 about a similar outpouring of its waves, and thus would the lake gradual- 

 ly sink by the same never-failing means, from level to level, until its 

 whole body of waters was expended, and so leave those trickling and ap- 

 parently insignificant snow streams which had ultimately caused its expul- 

 sion from the valley, not only to usurp its former bed, but to form by 

 their united waters the present river Spiti. 



From these facts a question naturally arises, as to the probable source 

 from whence the vast beds of marine exuviae found in the higher portions 

 of this valley have been derived, and the answer to it must entirely de- 

 pend upon the origin we assign to the lake itself. That is, if these moun- 

 tains and the lake were in existence before the Mosaic deluge took place, 

 it will follow, that the quality of the waters must have undergone a change 

 from fresh to salt by the influx of the ocean, and it might on this account 

 be contended by some that the marine shells rising with the waters, were 

 here left living when that ocean again subsided to its proper bed; that 

 as from that period the waters of the lake would gradually part with their 

 saline properties, as the snows around continued to pour down their limpid 

 streams, causing the lake again to resume its pristine freshness, it becomes 

 evident that those marine animals, exclusively formed and adapted for an 

 existence in salt waters, could only have survived there for a short time, 

 and would then have been deposited in one vast accumulation. But had 

 this been the case, the exuviae must have belonged to species still existing 

 in the seas, whereas we find them all to be the spoils of extinct animals ; and 

 again, had such been the case, they would have been imbedded in strata of 

 the tertiary formation, whereas, we find them in those of the secondary de- 

 posits, which are referrible to a period long antecedent to the Mosaic flood. 

 Thus, we must at once abandon this first position. 



Secondly. If we suppose that the lake was formed at and by the deluge, 

 and afterwards by the constant accession of snow water became fresh, — 

 the effect, as regards the marine deposits, will still be the same; and con- 

 sequently this second supposition must be abandoned likewise. 



