Cutting Engine. 3°7 



fcrews n n, is prevented from rifnig or falling, when turned 

 round, by a Conical fhoulder fitted into the upper fide of the 

 plate m ?n, as may be feen in the figure, and by the micro- 

 meter index wheel o o made faft to that end of the fcrew 

 which projects through the lower furface of m m. Therefore, 

 when the index is turned, the fcrew working in z raifes or 

 lowers i ; the latter by its form being prevented from turn- 

 ing with the motion of the fcrew. The piece i, being thus 

 raifed as much as the intended thicknefs of the flip to be cut, 

 preffes asitrifes againft the divifion b, and by that means makes 

 the brafs focket, in which the wood is made faft as before 

 defcribed, to rife exactly the fame quantity— care being taken 

 to regulate the prefTure communicated by the fide fcrewyin 

 luch a manner as juft to allow free aftion to the micrometer 

 fcrew, and yet to prevent any lateral deviation in the afcent of 

 the focket. A portion of the index wheel comes through the 

 front of the machine (o, fig. i.) ; and all that is neceffary to 

 raife the wood, the parts being previoufly adjufted in the man- 

 ner defcribed, is to lay hold of the knob that prefents itfelf at 

 the opening, and move it to the left, a half, a whole, or two 

 divifions, according to the thicknefs the flip is wifhed to be cut. 

 Thefe divifions are marked on the circumference of the index, 

 and you note the quantity that panes a ftationary point marked 

 over the centre of the opening. 



The cutting apparatus is conftru&ed in the following man- 

 ner : — On the further edge of the upper furface of the box, a 

 flat rule, G G, fig. i, made of fteel, is fattened down by the 

 fcrews k k : it is more than an eighth of an inch in thick- 

 nefs, and the front edge of it is ground perfectly ftraight, 

 and ftands at a right angle to the furface on which it reus. 

 Another flat rule, one end of which, H, may be feen presett- 

 ing paft the end of G towards the left, ferves as a bed for the 

 cutting knife r r, which is made faft to the rule by the fcrews 

 * s. The upper and under furface of this rule are ground 

 parallel to each other, and its back edge is ground ftraight to 

 Xa fit 



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