Page:Madras Journal of Literature and Science, series 1, volume 6 (1837).djvu/146

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Account of the Operations
[July

rock, and charged with 12-lbs. of powder each, at intervals of four and five feet.

24th. The holes were not sunk to the required depth, as the divers could not reach the bottom with their hands, and the sand or powdered stone was washed out of the ladles before reaching the top. Directed an auger to be made with a tin tube for this purpose. The work was, however, very good, and 1414 cubic feet of stone removed. The boat- swain with the convicts did more work than the sappers, which must be attributed to the excellent superintendence they were under.

25th. The holes were now sunk to the required depth, and one 10-lb. charge fired, which made a crater of about four feet in diameter. The other holes were charged with less, as the rock was found not to be of great thickness; three craters were produced, but the rock was not aa usual rent beyond the actual effect of the charges. We regretted much not having it in our power to have simultaneous discharges, which would make a large excavation at once. The present method will be tedious and fatiguing, from the length of time it takes to charge and return to the same spot. The rock is so exceedingly soft it offers little more resistance than clay, so on a perfectly flat body the effect was comparatively trifling; a considerable portion of rock had been detached, and 1524 feet was removed, through the energy of the person before mentioned, boatswain Morris; 103-lbs. of powder expended, in seventeen charges, without a single failure. The leather cases well dammered and dusted with lime, answer better than tin cases, and are of much less cost.

27th. Received a letter from the assistant government agent at Jaffna, and also the boat and machinery for weighing stones. The frame and wheel of this machine are calculated for a boat of double this size, and as much above the centre. It will not answer for stones of any weight, which is much to be regretted, as the machinery is of the best description, and the boat a beautiful model. Removed today 1143 feet of stone, part of the hands being employed on the Jaffna boat.

23th.—The wind has changed decidedly to the south, with more current and sand than we had before experienced, and the water discoloured. Three charges only fired, from the difficulty of finding the holes, but removed 1715 cubic feet of stone, the greatest quantity yet taken up.

29th.—Tried a raft, with a small iron windlass, as a weighing boat, which worked very well, but requires seamen and a European to manage it. Removed 1620 cubic feet of stone, though the current was strong from the south. We had previous to this been principally engaged on the south side of the reef, as being the most sheltered, but now ordered the work to the centre and north. A boat arrived from Colombo, with timber and catamarans, the wood of the latter very spongy, and in an advanced stage of decay. The season is too far