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upon a circle of fifty-four feet in diameter, and the whole carefully 

 leveled. A band of wrought iron fifty-four feet in diameter, half an 

 inch thick, and twenty-two inches wide, was then obtained and placed 

 upon this ring of plank. The band was made 'of sheets about four- 

 teen feet long, the ends of which were placed together, forming butt- 

 joints; over these ran covering plates, three feet long, and double 

 countersunk rivets were used to secure them. These having been 

 put in place and brought to a true circle, a ring of oak timber, cloven 

 inches thick, eleven inches wide on the top, and two inches wide at 

 the bottom, was placed inside of the iron band, the thin edge resting 

 on the short plank, and being in contact with the iron. This was 

 securely fastened to the band by means of bolts and spikes. Upon 

 this was laid another ring of oak timber six inches thick and twenty- 

 four inches wide, the inner diameter of the ring being fifty feet. 

 These two rings were securely fastened together by spikes ten inches 

 long and half an inch square. Seven courses of oak of the same 

 dimensions as the last were then laid up, making a total depth of 

 timber of four feet, the whole securely spiked and bolted. The iron 

 band reached to the top of the second six-inch course of timber, and 

 the third course projected over its edge so as to come flush with the 

 outside of the iron, thus forming a shoulder against which the iron 

 could press, and which would prevent its being forced upon the out- 

 side of the curb. Forty holes were then bored through this four 

 feet of timber, to receive the rods of one and one-half inch round 

 iron which were sixteen feet long. These rods were passed through 

 this mass of timber, and were held in position at the top by a turn- 

 plate. The wall of brick masonry, two feet thick, was then com- 

 menced upon this wooden curb, and carried up to a height of ten 

 feet, where four layers of pine timber, each six inches thick and six- 

 teen inches wide, were introduced. These were placed in the center 

 of the wall, and the iron rods passing through them were securely 

 bolted down with heavy washers and nuts. The wall was now six- 

 teen feet high, besides the cutting edge, which projected ten inches 

 below the main wall, and was securely bolted together. While this 

 was being done, a suitable derrick had been obtained, and so placed 

 that the boom would swing over the wall and command the interior 

 space also. Iron buckets for hoisting out the sand, and a six-horse- 

 power hoisting engine were procured. Work was then commenced 

 upon the excavation. The material from within the wall was exca- 

 vated and thrown into the iron buckets, and was then hoisted out and 

 taken away. The excavation in the center was kept below that at 

 the sides, and when sufficiently advanced, the material from inime- 



