162 New striking part for a clock. 



IV. 



Defer iption of a piking Part for a Clock, in which the InUrvah 

 between Stroke and Stroke are not regulated by a Fit/, but by a 

 Pendulum. By Mr. Edward Massey.* 



SIR, 



parrfor'i cSi. -^^VING for a number of years confidered that a method 

 of ftriking a clock, at certain regular intervals, might be of 

 great fervice in making obfervations on the heavens, andafcer- 

 taining the velocity of found, c;c. I beg leave to lay before the 

 Society for the Encouragement of Arts, ^c. a ftriking part of 

 an eight-day clock, u'hich I have no doubt will anfvver the pur- 

 pofe intended j and if, upon examination, the Society fliould be 

 of opinion that it may be ufeful, I truft they will reward it 

 according to its merit. They will find that tlie work of this 

 model is lefs than that of the common ftriking movements, and 

 may be made by a common workman, with lefs expence and 

 trouble; the weight required is alfo confiderably lefs. The 

 principle I aft upon is the pendulum, by which I regulate the 

 flroke, inftead of the fly ; the advantage of which muft be 

 obvious to every one. The machine confifts of a toothed wheel 

 A, one pinion B, a pin wheel C, pallets D D, pendulum E, 

 and locking detent G. The hammer-work F is as ufual, and 

 ftrlkes on the bell at H. The weight hangs to the cord I. See 

 Plate XII, Fig. 1 and 2, where a front and fide view of the 

 machinery are given, and where fimilar letters denote the fame 

 parts in each view. 



Defcription of the Machinery. 

 I confider it is only neceffiiry for me to give the defcription 

 of the wheels, fo as to be a dire6tion to a mechanic, who wiflies 

 to manufadure clocks on this principle. The main-wheel A, 

 with feventy-eight teeth> is to ad in a pinion of eight leaves, 

 H. The pin wheel C Hiould be large, fo that the pins on which 

 the pallets D and tlie locking G aa, may be flung as far from 

 the center as poffible, which pins may be eight or (ixteen in 



• From the Tranfaflions of the Society of Arts, 1803. This 

 Invention was honoured with a reward of 20 guineas, 



\number. 



