Meanwhile, a different set of afflictions had come upon the engineer and contractors in sinking the lake shaft and driving the heading toward shore. This shaft was intended to be built by sinking a cast-iron cylinder 10 ft. in diameter, made up of sections bolted together. Work was begun July 5, 1892, and the sinking was accomplished first by weighting the cylinder, and afterwards by pumping out the sand and water within it until the pressure from the outside broke through under the cutting edge and forced the sand into the cylinder, allowing it to sink a little. From 10 to 30 cu. yds. of sand were carried into the cylinder each time, and finally it was feared that if the process continued, the crib, which had been previously erected, would be undermined. On Sept. 6, therefore, the contractors were ordered to discontinue this method of work. No change was made, however, until Oct. 1, when the cylinder had reached a depth of 68 ft., and by this time there was quite a large cavity underneath the crib. This was refilled, and the cylinder pumped out, and excavation begun inside of it. On Oct. 11 a 2¹⁄₂-ft. deep ring of brickwork was laid underneath the cutting edge; but in trying to put in another ring beneath the first, two days later, the sand and water broke through the bottom, driving the men out, and filling the cylinder to a depth of 16 ft. with sand. The pumps were started, but the water could not be lowered to a greater depth than 60 ft. At the request of the contractors, the city engineer had a boring made at the center of the shaft to determine the character of the material to be further penetrated. This boring showed that sand mixed with loam and gravel would be found for a depth of 26 ft., then would come 15 ft. of red clay, and finally a layer of hard clay like that penetrated by the shore end of the tunnel. About the middle of December the contractors made another attempt to pump the shaft, but finding that the water came in at the rate of 25 gallons a minute, abandoned the attempt. In the latter part of February preparations were made to put an air-lock in the shaft and use compressed air. Hardly had the work been begun by this system when, on April 20, 1893, a terrific easterly storm swept the top of the crib bare of the buildings and machinery, and drowned all but one of the 15 men at work there.