A block is secured to each pair of legs for supporting a pair of ordinary grindstone rollers, which form a bearing for the balance wheel shaft. This shaft has formed in it two cranks, and it carries an ordinary balance wheel, to the side of which is secured by means of hook bolts a grooved wooden rim for receiving the driving belt. The cranks are connected, by means of hooks of ordinary round iron, with a treadle that is pivoted on the gas pipe at the rear of the table. The shaft will work tolerably well, even if it is not turned. The cranks must have half round grooves filed in them to receive the treadle hooks. The size of the different diameters of the drive wheel may be found by turning the larger one first and the smaller ones afterward, using the belt to determine when the proper size is reached. The wooden rim may be turned off in position by using a pointed tool. [Illustration: Fig. 1] [Illustration: Fig. 2] [Illustration: Fig. 3] [LATHES FOR AMATEUR MECHANICS.] The lathe above described, although very easily made and inexpensive, will be found to serve an excellent purpose for hand work, and if the holes, instead of being Babbitted, are bored, and if the bars forming the shears are turned, the lathe may be converted into a kind of engine lathe by placing a feeding screw between the bars, and putting a small tool post in the rest support. M. * * * * * MACHINE SHOP ECONOMY. In times like the present, when even with good management our best machine shops are enabled to exhibit but small margins of profit, and shops with indifferent management exhibit margins on the wrong side, it is a question of paramount importance what kind of economy should be pursued in order to maintain a successful business. The directors of long established machinery enterprises differ widely upon some methods of conducting business, and while one gains success by pursuing a certain plan, another, with perhaps as much ability, cannot pursue the same with satisfactory results.