183 7. J Experiment in Fort William. 237 



the situation of the two is similar enough. The calcareous infiltra- 

 tion which has consolidated the sand and gravel of the Sewalik and 

 Nerbudda matrix has been wanting here, and perhaps from its greater 

 distance from the hills alone, the sand here is in a much more com* 

 minuted state : — geologically speaking, however, the whole of the 

 fossils may belong to the same period of alluvial deposit — or, in 

 other words, to an indefinitely distant epoch of the present system of 

 quiescent operations in land and flood, whose gradual action has sub- 

 sequently accumulated the superjacent beds of clay, abounding in 

 minute fresh-water shells, extending for thousands of square miles 

 — and again over them towards the delta of the Ganges, other more 

 recent and extensive beds of blue clays, colored with vegetable debris 

 and containing imbedded peat and wood, by which they are identi- 

 fied with Jthe existing soil of the Sunderban forests. The mind is 

 lost in contemplating the immense periods which such a deposit 

 would demand at the hardly visible rate of present accumulation : — 

 yet there are other causes of wonder in the several beds of coarse 

 granitic angular gravel and nodular or pea iron ore which have been 

 traversed by the auger before reaching the fluviatile sand beneath, 

 These may indicate the volcanic upheavement and subsequently gra- 

 dual decay of granitic and ferruginous hills, pending the progressive 

 deposit of the alluvium, concerning which, however, we can know 

 nothing certain, and need not therefore lose ourselves in conjectures. 

 In like manner it might be advanced that the whole of the clayey strata 

 were deposited in fresh water as the saliferous sand and sandstone of 

 Upper India has been in salt water — and that the animals whose 

 exuvise are now brought to light at so many points, were the inhabi- 

 tants of the borders of a prodigious bason. In the upper beds of blue 

 clay penetrated in digging tanks and canals, bones have occasionally 

 been met with (see the note on those found at Dumdum in Vol. II., 

 page 649), but unfortunately none have been preserved. The occur- 

 rence of the remains of quadrupeds at one or two distant points of the 

 series is sufficient to establish the conclusion that their existence has 

 been coeval with the whole deposit ; while the sharp unworn angles 

 of the fort bone prove that the animal to which it belonged had lived 

 and died in the immediate neighborhood. 



In the accompanying sketch I have attempted to delineate of full 

 size, Colonel Macleod's fossil bone, which may be designated without 

 hesitation one of the most precious rarities ever deposited in the 

 Museum of the Asiatic Society. 



J. P. 

 2 i 



