jtfrti 



At this depth the baring tackle having fever'al times given way 1 , aad 

 the borer remaining- li-riexfricable from the ground, the further profe- 

 cution of the experiment was abandoned. The different flrata, through 

 which it penetrated, nave furnifhed the following obfervatiohs. 



1. The primary object of getting at fprings of frefh water entirely 

 failed, of which fanguine expectation had been formed by the projec- 

 tor of the experiment, grounded, as it fhould fcem, upon the com- 

 mon opinion, that the foil of all the lower part of itenga/ was particu- 

 larly moift and full of fprings ; an opinion, which this experiment, if 

 it can be taken as affording any criterion of the foil throughout the 

 vicinity of Calcutta, has fo far happily difcountenanced. The firffc 

 appearance of any damp was at the depth of 71 feet, in a reddifh clay 

 with a quarter of fand, and below 76 feet the earth was as dry as be- 

 fore ; though the borer muft have defcended nearly to the level of the 

 fea, which as the crow flies, cannot exceed 70 miles in diflance, while 

 the fall of the river is commonly computed at one inch a mile accord* 

 lug to its bendings. . 



2. The damp of the climate, not being attributable to the moifl 

 nature of the foil, nor affe&ed by it, otherwife than as an admixture 

 of f'altpetre in the foil may be fuppofed to have fome influence on the 

 exhalations from the furface, muft be looked for principally at lead 

 from caufes upon or above the furface • to the want of a general fyftem 

 of drainage in a level country, and the luxuriant vegetation, with in- 

 adequate openings through the woods for ventilation, which prevent 

 or impede the copious falls of rain at the periodical leafon, and not 

 unfrequently at other times, from running off properly. The heavy 

 dews at other feafons, are not probably more than fufficient to fupply 

 the daily exhauflion of the fun, and would rather contribute to the 



