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 73. Boston Navy Yard.—The Boston Navy Yard is of great extent, and contains three large sheds for ship-building, one of which is now used as a store for timber; another is occupied by the ship "Virginia," which has been on the stocks for more than twenty years; the third is empty. The manufacture of rope is carried on on a very extensive scale. A building 1,360 feet long, contains a rope walk where a length of upwards of 1,200 feet of rope may be made. There are also the means of making 24-inch cables.

Machinery is used for making sheaves for ship blocks. An ingenious machine is employed for boring the sheaf, and recessing it on both sides for receiving the bush. Two lathe headstocks are mounted on a frame, and carry the small revolving cutters for making the recesses. An universal concentric chuck, with three "jaws," having a large hole in its centre, is mounted between the headstocks. This carries the work, and has a vertical adjustment.

74. Springfield Armoury.—Springfield Armoury is beautifully situated on an eminence overlooking the town. The various buildings together form a quadrangle; the grounds, which are tastefully laid out, occupy an extent of about 40 acres.

I was conducted over the establishment by