BY JA3»IES C. COX, M.D., F.L.S., ETC. 27'J 



to allow the rods to become jammed by the quantity of sand or 

 debris of the boring which was suspended in solution while the 

 drill rods were rotating, and by a cessation of this motion the 

 sediment settled down and jammed the rods. This was proved 

 to be the case when an attempt was made to haul up the rods. 

 A force of about 15 tons was employed, with large double and 

 treble blocks, and ro]De of large dimensions which snapped like 

 a thread as soon as a strain was exerted. Finding that this 

 power was insufficient to raise the rods, one of Sir William 

 Armstrong's powerful steam hydraulic pumps was used to force 

 a pressure of water down the tube to remove the sediment. This 

 proved ineffectual, owing, no doubt, to the corroding of the jjipes 

 with the wet sand, which prevented the water from passing 

 between the tube and the borehole. So great was the pressure 

 that, while the pump was working at the rate of 100 revolutions 

 per minute, when the pressure must have been considerably over 

 1000 lbs. to the square inch, one of the tubes burst, and thus put 

 an end to pumping operations. Another method for raising the 

 rods was then tried, which proved so far successful that 1400 feet 

 of rods were drawn from the hole. No doubt the whole of the 

 1860 feet could have been successfully extracted had not the stand 

 piping, which had been driven through the sand for 143 feet from 

 the surface, shifted its seat, or original position, on the hard rock 

 to which it was first driven. The shifting of a quarter of an inch 

 on one side would have been sufficient to permit the sand to come 

 in, and fill the bore. I may here mention that the stand-pipe 

 was fixed to its place on the rock by cement, which casing of 

 cement must also have been displaced and broken before the sand 

 coidd enter. 



I have thus given you a hurried sketch of the strata met with 

 in this important experiment. A minute analysis will still be 

 required of each core of rock ; and it is to be hoped that it will 

 fall into the able hands of our Government Gfeologist, when we 



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