1848.] 



an Artesian Well at Tuiicorin, 



269 



stage of planks formed for the people to work on. I should mention 

 that salt water was met with at the above depth. The next thing 

 was to fix one of the 6 inch diameter iron pipes in the centre of the 

 pit, after which was done the boring commenced. 



The nature of the soil bored through (sand and blue clay mixed, 

 the former, however, predominating) made it advisable to use an 

 auger, and occasionally an instrument termed a shell, furnished with 

 ''a valve opening upwards to raise the water as well as sand from the 

 interior of the pipe. Every time the auger was removed the head of 

 the pipe was struck with a heavy wooden rammer, to assist its 

 descent, and in this way 6 feet of pipe were inserted the first day. 

 On the 16th the second pipe was fitted on (each pipe being 9 feet in 

 length) and driven down to the depth of 5 feet, making 1 4 feet in 

 all. At this depth there was no diiBculty in keeping the bore free 

 of water by means of the~valve shell. The soil brought up continu- 

 ed to be of the same description as before, but the ingress of water 

 was much less than on the first day. On the 17th, the second pipe 

 was driven to a level nearly with the surface of the water in the pit, 

 or about 19 feet from the surface of the ground, at which depth a 

 much firmer clay, with shells intermixed, was met with. It was 

 found necessary to loosen this a little by means of the screw auger, 

 before the common one was introduced, and even then some difficulty 

 was experienced in working through it. The percolation of water 

 from below was very trifling. A small crab winch was used for 

 raising and lowering the boring rods as occasion required. The 

 party engaged on the work consisted of 16 men, 8 of whom were 

 employed alternately in turning the auger and raising the rods. From 

 the 17th to the 27th idem very little progress was made in the 

 bore, owing partly to the heavy rain which fell in the interim, and 

 partly to the breaking of the iron pin connecting the upper and low- 

 er boring rods, whereby the latter was left at the bottom of the bore, 

 and had to be drawn up separately. In doing this, the rope, to 

 which the lifting instrument was attached, broke, and both fell to 

 the bottom together. A long iron bar hooked at one end was then 

 introduced into the bore, and by its means the broken part of 

 the rope, with the instrument attached, was drawn up. The next 

 attempt, with a stronger rope, was successful in withdrawing the 

 lower rod from the bore, and a new pin being inserted the 

 boring proceeded. At the depth of 20 feet a whitish clay with 



VOL. XV. NO. XXXIV. X 



