This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1877 edition. Excerpt: ... CONTEXTS. CHAPTER I. MECHANICAL POWERS. FAGS Elementary Works on Natural Philosophy . 17 Elements of Machinery 17 The Lever 20 Th3 Inclined Plane .29 The Wedge 32 The Screw 34 The Pulley and Cord 40 The Crank 42 CHAPTER II. FLY AND BALANCE WHEELS. Centrifugal Force and Circular Motion ..... 50 Action and Reaction 54 Friction 63 CHAPTER III. TRANSMISSION AND TRANSPORTATION OP MOTIVE POWER. CHAPTER IV. PECULIARITIES AND PROPERTIES OF WATER. Taking Levels Fitting down Sills under Water .... Washing out a Mill-race or Foundation by Sluicing Pressure of Water ...... Velocity of Falling Water ..... Tables (iii) INTRODUCTION. The occupation of a millwright differs from that of almost all other tradesmen and mechanics, in that he is compelled to accommodate his work to a greater variety of circnmstances, conditions, and contingencies. For instance, a millwright is employed to build two saw-mills, one is to be in or near a city, convenient to foundries and machine-shops, where a great variety of waterwheels, and all the other machinery required for its construction can be obtained cheaply and in abundance. But the water power and site are valuable here, and he must select the water wheels, and adapt every part to do the required amount of work with the least possible waste of water and room, and all the machinery and many of the fixtures will be of iron. The other saw-mill is to be built back in the interior of the wilderness where all supplies must 1*2 packed and carried at great expense; and here, almost the whole mill and machinery must be improvised of wood, on the spot. Timber, water power, and space being of little value, while iron is a precious metal, and he must exert his ingenuity to construct a mill that will do the required w