420 



FAUNA ANTIQUA SIVALENSIS. 



XXVI. NOTE ON AN EXTEAOEDINARY VARIETY 

 OF ELASTIC SANDSTONE.' 



I HAVE lately had sent to me to look at, by Captain 

 McNaghten, of Kurnal, a specimen of rock which has sur- 

 prised me beyond measure. It is a slab of sandstone 14 

 inches long by 5| wide, and two inches thick, and looks like 

 a long brick. It exactly in appearance resembles the building 

 sandstone used at Agra. It is flexible and elastic in every 

 direction ! If you place it flat on a table, and press the 

 hand on one end and raise the other, you can bend it to a 

 certain extent, and see the undulations moving along to 

 the fixed end. If you seize it by both ends, one in each 

 hand, and make an action as if jou intended breaking it, 

 you can see and feel it hard like a piece of whalebone, but 

 of course in an infinitely smaller degree, and the undulations 

 are observed propagated from end to end. If you tap it on 

 the side with the finger as you would a miissak of water, it 

 yields pretty much in the same fashion, propagates an un- 

 dulation, and instantly recovers its form. If you press it at 

 the sides it gets narrower, and if you pull at the ends it 

 elongates ! but it always recovers its original form. Is there 

 any account on record of so extraordinary a sandstone ? 

 Should there not, I may send you some notes about it. It 

 is not known where the specimen came from. 



H. E. 



' This note was communieated to the 

 Secretary of the Asiatic Society of 

 Bengal in April 1837, and was published 



in the 'Journal' of the Society, vol. vi. 

 p. 240.— [En.] 



