Mr AIRY ON A NEW CONSTRUCTION OF THE GOING-FUSEE. 225 



In all cases, the center of the pinion, the center of the toothed-wheel, 

 the pivot of the lever-frame, and the center of the winding-up-wheel, 

 must be in the same straight line: and the pivot of the lever-frame, 

 the place at which the cord is a tangent to the barrel, and the place at 

 which the teeth of the winding-up-wheel act on those of the barrel-wheel, 

 must (as projected on the clock-plate) coincide. 



I shall terminate this paper by referring to the two isometrical draw- 

 ings of the new going-fusee, in figures 7 and 8. The first, fig. 7, re- 

 presents the lever-frame with the barrel, toothed-wheel, internal ratchet, 

 and clicks, as viewed from the side on which the clock is wound up. The 

 clock-plate is supposed to be taken off: and, as the winding-up-wheel k 

 is carried by the clock-plate, the support of that wheel is not represented. 

 The second, fig. 8, represents the whole of the mechanism, as viewed 

 from the side opposite to that on which the clock is wound up : the clock- 

 plate opposite to the winding-up-side being taken off. 



G. B. AIRY. 



Royal Observatory, Greenwich, 

 Feb. 5, 1 840. 



Vol. VII. Pari II. F F 



