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i which IS iixed on the axle S, between tiie racks,; and depresses it till 

 it overcomes the resistance of the bar x, &c. which will be thrust for- 

 wards, and act on the pin as in the underside of the roller V, and also 

 turn the roller in the same direction, as by* depressing the lever v, 

 which will disengage the click .v, and engage the click t in the rack^: 

 then the carriage will be in proper trim for traversing to the other end 

 of the axle S, which is performed by the action given to the treadles, 

 which is also communicated to the pulley 2, on the end of the axle S, 

 and therefore causes the axle to vibrate half a turn, each motion of 

 the treadles: as the axle is in the act of turning in the direction of the 

 arrow, the circular inclined plane n, acts against the end of the rack g, 

 and pushes it along the groove in the axle S, together with the car- 

 riage U, &c. equal to one notch or tooth of the rack; when the axle has 

 returned half wa)^, the spiral spring h presses back the rack g to its 

 former situation, without moving the carriage U, on the axle S, (as 

 the rack is at liberty to slide in that direction under the click, without 

 butting against one of the teeth;) and by repeating another vibration of 

 the axle, the carriage will be moved forward another tooth, one tooth 

 each vibration, and so on, till the carriage has arrived at the other end 

 of the axle S, then the other end of the bar x, will be brought in con- 

 tact, and pushed against a spring z, (which is fixed on the upper side of 

 the axle, between the racks, at any required distance from the spring 

 ;//, between the racks, according to the number of strings or lashes r r, 

 that the figure may require,) till the spring overcomes the resistance of 

 the bar x, &c. which turns the roller V, and changes the action of the 

 clicks s and /: then the carriage U will traverse back one tooth for each 

 vibration of the axle S, by the action of the circular inclined plane m, 

 on the rack f, till the end of the bar x comes in contact with the 

 springy, when the action of the clicks s and t will be again changed. 

 The racks y*and ^, both slide backwards and forwards, the extent of a 

 tooth, by the action of the two circular inclined planes m and n, for 

 each vibration of the axle; but, as only one of the clicks is allowed to 

 act on the rack at the' same time, the motion of the other rack does not 

 interrupt the progress of the carriage U, &c. The frame which con- 

 tains the joint end of the click 6, can be so adjusted by the screw 3, that 

 the carriageU will be stopped by each vibration of the axle S, in a situation 

 differing by half a tooth, according as it traverses one way or the other; 

 so that a different set of strings or lashes ?: r, &c. will be drawn at each 

 vibration of the axle, till the carriage U has traversed backwards and for- 

 wards on Ihe axle S. W and X are two rails of wood, fixed on the 

 upper side of the frame R R of the draw-boy, and parallel to the axle 

 S; on the inner edge of the rails are fixed double the number of wire 

 staples 4 4, &c. to that of the teeth in the rack^ and g; the staples 4 4, 

 &.C. act as guides to the"strings or lashes r r, which pass through them, 

 and are fixed to the rail Y, which has four rows of holes, through which 

 the strings r r, &c., are passed and retained by a knot on the under side 

 of the rail; the number of holes is equal, and opposite to those of the sta- 

 ples 4 4, &.C. and is also parallel to the axle S. In the end of the rails 

 W and X are slits, through which the screws 5 pass, that fix them to 



