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Boring Operations in Fort William, [No. 103. 



On the 28th of April the actual excavation of the bore was com- 

 menced with a six inch auger, being that adapted to the tubing 

 it was intended to employ. On the depth of 120 feet being attained, 

 the quicksand, which had rendered the first attempt abortive, was 

 again met with. The experience of its previous effects had render- 

 ed apparent the necessity of securing firmly the joints of the tubes, 

 which was acco'rdingly done by means of four short, but strong 

 screws, in the manner represented in sketch No. II. To this precau- 

 tion the success of the work so far was undoubtedly to be attributed, 

 as the difficulties were found most serious from the loose, even semi- 

 fluid, consistence of the sand, which on the removal of a portion of 

 the water, then standing in the tubes within 15 feet of the surface, 

 immediately rose to seventeen feet, and though the work was conti- 

 nued night and day, actually rose faster than its removal could be 

 effected, so that at the end of eleven days and nights of incessant toil, 

 it had risen from 124 to 103 feet. 



Hence it became evident, that the only mode of overcoming the 

 obstacles presented by the sand, was to force the tubes down till 

 coming in contact with some firm stratum, the sand should be exclud- 

 ed ; by unrelaxing perseverance and much labour, frequently with an 

 advance of not more than a few inches in the day, the tubes at length 

 attained a depth of 157 feet. The sand was then perceptibly gained 

 upon, and at 159 feet a stiff clay was reached, and the borer which 

 during the prevalence of the sand was always behind the tubing, 

 now passed it, and in twenty-four hours attained a depth of 175 feet. 



The open auger it was found could not be used with effect ex- 

 cept in working through clay ; a valved instrument, therefore, called 

 the "Mudshell," had hitherto been employed for raising the sand. 

 This tool however here became useless, from some defect in the action 

 of the valve, which failed either to admit or retain the sand, now 

 coarse and gravelly, and in consequence it was found impracticable 

 to penetrate with it beyond 175 feet. One of the augers however 

 being fitted with a valve, and otherwise altered so as to retain the 

 sand, was employed with partial success, but not to an extent suffi- 

 cient to prevent the sand rising in the tubes, since after working 

 twenty-one days, and the tubing having been forced down to a depth 

 of 177 feet 2 inches, it was found impossible to work the auger 



