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[[right corner]] (158 [[/right corner]]

[[red ink]] A Sketch of the first Principles of an Engine to turn Squares [[/red ink]]
    Fig. 1. AB represents two equally sized wheels, with an equal number of teeth, fixed on their axis's, C and GD running in the pieces EF; the top wheel is divided into four equal divisions, in which are fixed four pins, as [[underline]] aeio, [[/underline]] at the end of the axis GD; at G is a square hole to put a mandrill in, on which is fixed the wood. In the 2. [[superscript]] nd [[/superscript]] fig. you have the wheel A with its four pins to lift the leaver [[underline]] cdf, [[/underline]] running on the center [[underline]] c, [[/underline]] and with its end [[underline]] f [[/underline]] moving the tool with its handle H, in order to cut the square [[underline]] wxyz [[/underline]]. The figure, as well as the principles, are so plain that I shall say no more to describe it, very little consideration being necessary to make the whole scheme plain and easy. After the same manner, a triangle may be turned, if the circle be divided into three parts, and from the same principles medals, faces, &c.  
     I.B.N. (Gents Mag. Vol. 22. for June 1752. p. 271.)

     Fig. 3. ASB is a [[underline]] convex [[/underline]] block, on which the glasses a, e, i, o are fixed by cement, with their edges contiguous and level with each other; the block turns on its center by the spindle C, while the ^ [[insertion]] concave [[/insertion]] tool DFE, is pressed on the glasses, and grinds off their edges gradually towards the middle of each, till they are formed to the same circle of convexity, as the tool is concave.

    Fig. 4. ABS is a [[underline]] concave [[/underline]] block which turns upon the spindle C, with the glasses fixed by cement in the concavity as at a, e, i, o, with their edges contiguous & even with each other, while the [[strikeout]] [[?]] [[/strikeout]] convex tool DFE, grinds the middle of the glasses concave. 
[[left justified]] I.B.N. [[/left justified]]

   Abbreviated from Gents Mag. Vol. 22. for Decr. 1752. p. 565.

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