[ 305 J 



LIV. Account of Improvemcrds for dhnimshmg Friction 

 in Clocks. By Mr. Edward Massev, of Henley, in 

 Stajfordshire *. 



-Having for a consklerable time considered a method of 

 diminishing the friction in escapements of pendulum clocks, 

 which I conceive may be of great service in making better 

 time-keepers, by relieving the pendulum from obstructions 

 occasioned by friction in the train of wheels, and on the 

 acting part of the pallets, I beg leave to lay before the So- 

 ciety fur the Encouragement of Arts, &c. two escapements, 

 which I have nD doubt will answer the purpose intended. 

 The difficulties which I propose to diminish in clock escape- 

 ments, by this invention, are as follow : — First, it is al- 

 lowed, that when the pressure against the recoiling escape- 

 ment is diminished, as it is liable to be, from increase of 

 friction in the wheel-work, the vibrations of the pendulum 

 will not be performed in so short an interval. This cir- 

 cumstance has the contrary effect on a dead beat; for, when 

 the pressure against the locking is the greatest, the vibra- 

 tions will occaipy a longer interval of time ; so that the vi- 

 brations of the pendulum arc liable to be affected from two^ 

 causes — from an increase of friction on the acting part of 

 the pallets, and from an increase or variation of friction in 

 the train of wheels. These are the objects which I have 

 bestowed great pains and expense to remove. 



I beu: leave therefore to give a description of two models 

 of my^improvcd escapement, that accompany this letter. 

 First, a swing wheel is made, in the usual way of making it 

 for a dead beat, except that it is not necessary to make the 

 teeth with fine points. The pallets, instead of being fixed 

 on the verae in the usual way, are fixed on two light de- 

 tents, one'on each side of the swing wheel. The lockings 

 are on the inclined planes of the pallets, which are pressed 

 against the teeth of the swing wheel by remontoiring 

 springs, which should be under the command of the weight 

 or main spring, so that if an increase of friction should take 

 place in the wlieel-work, the vibrations of the pendulum 

 will not be nnieh affected so long as there remains a power 

 to raise the inclined planes. A momentum is eommuni- 



* From the Transaciions of ihf Sode/y for the Encouragement of Arts. 

 fJlanufaciurti, ar.cl C'lmmtne, s'A. xxi. — The society voted a hounty of 

 fifty pounds to the invemor. Models arc preserved in the society's re- 

 pository. 



No. je. Jl/wy 1S04. I' 'ZiS.i'i'X 



