?;yOOLF's ROTATORY APPARATUS. 133 



XL 



On Mr. Woolf's Invention for equalizing the ASlion of a 

 Crank, in contradijiinaionto the Efftd of the Fly, in pro- 

 ducing an uniform Efedt againji a variable Rejijiance. In a 

 l^etter from Mr, T. Jones. 



To Mr. NICHOLSON, 

 SIR, 



1 BEG leave to fecond Mr. Fafcy's requefl: for an expla- J"^"j'y !1^P^S;' 



nation of the fubftitute f<^r the fly and equalization of the fubftitute for a 



adion of the fteam engine, in producing a rotative motion, fly. 



given in your valuable work for November laft : or, I (hall 



efteem it a favour if you can dire<5l me where I can fee it 



at work *. It appears to me, that the inventor has loft fight 



of the value of that organ which he intends to fuperfede, 



and that he has not applied it in cafes, where a machine is 



required to produce an uniform efl^e6l on a variable refiftance, 



in which cafe the mere equalifation of the a6lion of the 



power on a revolving crank would have no value at all. 



The beft attempt that I h^ve feen to unite thefe two im- Another attempt 

 portant points, is in a fteam engine ereded by Mr. Horn- gfje^^ 

 blower, at MeflTrs. Meux and Go's, brewery, where the 

 a6lion of the power on the pin of the crank, may have been 

 in the ratio of the fines of each refpedlive arc in its revo- 

 lution round the arbor of the fly, I fay, " may have been" 

 and I wonder '\t was not, (ince that mode of communication 

 would have fo eafily admitted it,-— theoretically at leafl: ; 

 |hen indeed, a very light fly would ferve to turn the crank 

 paft the upper and nether part or points of the circle ; but 

 it could not have anfwered in regulating the unequal refif- 

 tance which is found even in grinding malt^i or pump works ; 

 and in my humble judgment, the fly muft for ever keep its 

 place and importance with evepy judicious mechanic, 

 I am, in rnuch bodily indifpofition, 

 S I R, 

 Your humble fervant, 



T. JONES, 

 Surry Roadj 1th Januari^ 1804. 



* If there be one at work near London, I have no doubt but Mr. 

 Woolf the inventor, who is refident engineer at Meflrs. Meuj^'s 

 brewery, will readily (liew it, N, 



Farther 



