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FORE:A proof of this last proposition is found in the fact that a thorough latheman will perform nearly as much work and do it as well on an old English lathe with plain screw feed, as can be performed on the more complicated lathes of modern construction; but as economy of skill is sometimes an equal or greater object than a saving of manual labour, estimates of tool capacity should be made accordingly. The main points of a lathe, such as may most readily affect its performance, are first��truth in the bearings of the running spindle which communicates a duplicate of its shape to pieces that are turned,��second, coincidence between the line of the spindle and the movement of the carriage,��third, a cross feed of the tool at a true right angle to the spindle and carriage movement,��fourth, durability of wearing surfaces, especially the spindle bearings and sliding ways. To these may be added many other points, such as the truth of feeding screws, rigidity of frames, and so on, but such requirements are obvious."Ah, this is serious. How did you know that?"