( 5 8 9 )

i. TheFallacy os the Autbors Reasoning Jies in this; He siipposes Copper o{Siv*n :*tpr t $i.3 Ounces in a Foot Square to be of sufficient Thicknels to Resili: the Fics/it. h 00 'Lsure of the Air in a. Globe of 14 Foot Diameter , nay os any Dimenjkns■ But inii>4. s- - vthis we can nowise Assent to bim : For the Pressure from without Inwards,though it be always the lime upon Equal Sursaces, yct upon llacqual Stir-iae es the Cale is quite otherways, for there the Pressure will be found, notthe lime, but to Encreale always in the fame Proportion with the Stiriace,and thence conlequcntly the Tbiclyiess ofhfs Copper,. or any Meta! or Material,which he (hall make ule of, muli Increale in the fame Proportion, with theDiameter of the Sphcrc, and conlequcntly the iVeight of his Coppcr muli al-ways lncrcafe in the fame Proportion at least to the Solidity of his Sphcrc ; fr>that by his Augmenting the Qiiantity of his Sphcrc, he has no mannet ofAdvantagc of making it proportionably J.ightcr than the Air, and propor-tionably S nötig, but the contrary: For it is manifest, That a Bigger Sphcrc16 made of any Matter we yet know, has leis Power of Refisting the lima ■

Pressure of the Air than a Leis, becaule of the Finite Resistance os Matter 'to Pressure, there being lome degree of Prcjsurc that will Cruso every Body. -

XVI. This Engine is compolcd of four Principal Parts; the Sapent A ..

two Foot-Steps or Treddlcs B B, one C/appcr C, and two Antis DD, DD. -imm-»

The Serpent or Iron Bar A A, has two Elbows E E, where to the Ends^^j’- ¥ M ‘ <ieof the Ropes are fix’d that Raile and put Down tlie Vootßcps B B, ,’ e uo . f.ioo;-FF are two Fourrhs of a Circle, that siiccellively Rest upon two Arches or -4z

Bows of Iron G G, which are above the dapper C, to Raile it. H H aretwo Feeth of-Ironj added to the Serpent making an Angle of 2 y Deg. withF F, and K K, which lerve to put Down a Base ule, or Swecp, which ,'s inthe Arm that carries th t-Shuttle. The Footsteps or T rcddles disser in nothing-from thole which are ufually made use of, only the Cords that hold rhem.

Pendent from the Ground are fixt in the Elbows of the Serpent, which inturning Railes and puts t-hem Down by the help of two little Pullies, uponwhich the Ropes turn»

The Clappcr is supported between two Pillars with a Ropc double twisted,which makes it to make a kind- of Spring, and caules it naturally to give for-wards to Beat the Cloth.

L M, is one of the Arms w hich paß frcely inro the Canal or Pipe N N,supported by four Pillars of'Wood 0 0*00. Tiie Motion of it proceedsfrom the following Parts. P (f. is a Bafcule, which, though. uncqually di- •vided by its Supporter R, is yet in /Equilibrio, the End PR being made toweigh exactly as muc.h as- R Q.

At rite Extremity of this Bafcule is ty’d a Cord which passes thrdugh,the PuIJy S, and terminates at the Extremity of the Arm, where it is fast-ned to a little Bowl M. Af-thcothcr Extremity or the lame Atm, that isro läy rowards L, is also fastned underneath, a Cord which pjfles thronghtue Pulley T, and which carries the VVeighc V.

At the lame end of the Arm is added a little Kiele X, about rite bignefiothalf the Shuttle . ihen over a little Bar X Y, which passes srhwart xhe-Amy