The aim of the Author in writing this book has been to present in as comprehensive a manner as may be within the limits of a single volume the history and development of the lathe from early times to the present day; to briefly discuss its effects upon manufacturing interests; to describe its practical use on various classes of work; and to compare in a representative, theoretical, and practical manner the Modern American Lathes as now built in this country.<br><br>In carrying out these aims the early history of the lathe is traced from its crude beginning up to the time when the foot-power lathe was the sole reliance of the early mechanic. Then the early history of the development of the screw-cutting or engine lathe is taken up and carried on to the middle of the last century. This is done to put the student and the younger mechanic in possession of the facts in relation to the origin and development of the lathe up to within the memory of many of the older mechanics of the present day.<br><br>The matter relating to the early history of the lathe is introduced for what seem to be good and sufficient reasons. If we are always to " commence where our predecessors left off" we shall miss much valuable information that would be very useful to us. A retrospective glance on what has been, a review of previous efforts, a proper consideration of the road by which we came, or by which earlier workers have advanced, is not only interesting but necessary to a full and complete understanding of the subject, and very useful to us in mapping out the course for our continued advancement in contributing our share in the development of mechanical science.