C J 
as many parts that bear lefs then 20 inches, as there are that 
bear more, and the increafe of prefllire following an Arith- 
metical Progreflion, it is undenyable, that all thefe preffures 
added together, will do no more than one uniform preffure, 
that would be equal to 20 inches every where. 
Having thus found the quantity of preffure caufed by the. 
Mercprf Within the Bellows, we muft remember that the 
preffure of the Atmoffhere within the fame Bellows, is equi- 
valent but to 5 inches, as I obferved in my firfi: Paper vid: 
Philofophical Tranfaftion No. . 177 fag. 1241 : So that we 
find that the inward preffure is equivalent but to 2 5 inches 
ofMercurj in a 11. Now the preffure of the Atmofphe rt' upon 
the outfide is every where equal to 27 inches ; from whence 
it appears that the preffure without is ftronger than the 
preffure within, and ib I had reafbn to fay, that the Bellows 
flaading upright,; muft rather fhut than open. 
J did not think to have given this Computation fb at large, 
but I have been neceflitated to do it ( as I faiid in the begm- 
ning ) fince my firfl Paper was not fufficient to make me be 
underflood by thp Author of the Perpetual Motion, howe- 
ver, I will be careful to fave the time of the Reader as much 
as I can ; and although I might obfervefome other things in 
his Defcription^ that will increafe the difficulty of opening 
the Bellows, I forbare to fpeak of them ; and I will ftick on- 
ly to that which is moft material, and makes his Perpetual 
Motion to be altogather impoffible. 
As for the Argument the Author drawes from comparing 
his Engine to an ordinary Siphon \ I do befeeqh him to con- 
fider what a difference there is .between a Siphon that lets the 
water run down at the bottom, and his Engine; that fhould 
gather up the heavy liquor liitb' the jhigheil part of the In» 
ft'rument, and I do not queflioi^ybui wiU acknowledge the 
weakncfs of this Argument. ' , 
A 
