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 3 to 9 inches wide, and of a thickness tapering from ⅜ to ⅛ inch, at the rate of from 7,000 to 10,000 per day, according to the nature of the wood.

Timber is also cut up into laths 4 feet long, at the rate of from 60 to 100 per minute, by a circular saw attended by two men.

26. Saw Mills, Buffalo.—In these mills boards were sawn into "sidings," that is, long wedged-shaped boards for the sides or roofs of houses, by a circular saw, at the rate of 17 feet per minute. The board is introduced at the back of the saw, and moves in the direction in which it revolves. It thus cuts with the grain, and the strength of the cut assists the forward feeding motion of the board.

Subdivision of manufacture is advantageously adopted as a system.

Many works in various towns are occupied exclusively in making doors, window frames, or staircases by means of self-acting machinery, such as planing, tenoning, morticing and jointing machines. They are able to supply builders with the various parts of the woodwork required in buildings at a much cheaper rate than they can produce them in their own workshops without the aid of such machinery.

In one of these manufactories, twenty men