1847.] executed on the Sea Beach , Madras, 



185 



tecting cylinder nine inches, after which all attempt at sinking- 

 them deeper was given up and the auger and water cylinder con- 

 tinued in action throughout the day. The soil — coarse sea sand, — as 

 hitherto ; and, from the quantity brought up a depth of 28 feet should 

 have resulted, but at no time during the day did we exceed a depth 

 of 24 feet 3 inches, making it plainly appear, that although sand may 

 be excavated until the whole Beach be undermined, still a greater 

 depth than that now arrived at cannot be attained without the pro- 

 tection of a cylinder to accompany the auger ; notwithstanding this, 

 a depth of 14 inches was all that could be reached by the auger 

 when worked by five men — showing, that the soil although permea- 

 ble to sea water, is still capable of resisting in an eminent degree 

 the advance of solid bodies. 



Sixth and seventh Tuesday^ 29th, and Wednesday, 30th. — Having 

 day, 33 ft. 0 ill. completed the manufacture of an Iron cylinder of 

 23 feet in length by 6J inches diameter, it was lowered within 

 the 9 inch cylinders hitherto employed, and boring recommenced. 

 In the course of the day, as the smaller cylinder began to des-t 

 cend, the larger one likewise began gradually to settle, and dur- 

 ing this and the following day (in proceeding from 24 to 34 feet) 

 the two cylinders continued to advance simultaneously with the pro- 

 gress of the boring. 



Ei°-hthday 34 feet Thursday, 31 si. — The cylinders had becomes lug- 

 10 inches. gigh in their movement and consequently a corres- 



ponding small depth of boring only was effected, viz. (1 foot 10 

 inches) although a large amount of sand had been brought up by the 

 water cylinder. 



i^inth day. 44 feet Friday, August Is^.— The large amount of exca- 

 3 inches. vation, effected yesterday, rendered the descent of 



the cylinders this day most decided. The soil consisted of layers 

 of sea sand with broken shells and stiff black mud ; — the borer was 

 unable to penetrate beyond a depth of 10 inches into the soil, not- 

 withstanding which, the progress made by the water cylinder was 

 most rapid, in as much as a depth of 9 feet 5 inches was gained dur- 

 ing the day, the cylinders settling a little but not quite keeping 

 pace with the borer. 



Tenth day 47 feet ^^.twday , 2nd. — The larger cylinders advanced very 

 3 inches. sluggishly to-day, and notwithstanding a large amount 



of excavation was effected we had only gained three feet during the 

 day, or had arrived at 47 feet 3 inches from the surface soil consist- 



z 



