Weight f illing' at the Ro^e does this, for it fixes ' (asit 
Were^j'the end of the^EJbpe 5, a: ad yet it permits it to 
twift aad untVi^ifl:. . Ai:id the reafon of this twifting and 
untwifting is plain,- for the little particles of moifture in- 
finuating and foaking into the Cord are like fo many 
Wedges, which mnfl needs Oiorten the Rope, as a Blad-'? 
der isibo^rtned bv hfei^gWown op, and will lift a great 
w^ight/as Dr. l%//^> difcoiirfes at large in his Mecha-f 
nicks J but the eafieft wa , for the Rope ^B. to fliorten 
and lift up the weight is to do it by way of fcrew> for it 
felt is a fcrew, the ftrkads thereof being twiftedfand 
each particular thread in it,)fGrew-wife, and confequent* 
iy muft give a circular motion to the Index. 
To make an experiment of this, I wetted k Cord and 
hung it up with the Weight at the end of it, and I per- 
ceived as it dryd it untwifted, and that too very quick, 
fo as to be perceived by the Ey ; after the Cord had io 
far untwi£led/as I thought it had come to that degree of 
dryneis, that the prefentConftitution of the^^r would 
permit, I took a bafon of v/arm water that ient out a 
Steam and Fume, and placed it under the Cord ; immer 
diatly the Cord began again to twift very quick, and 
lo continued till the Water ceafed Fuming, or was re- 
moved, and then immediately it began to return its 
twifts. I then tryed to breath upon it gently with my 
breath, and found according to my expe<9:ation, that 8 
sor 10 breathings would twiftit;' degrees of a Circle. I 
then permitted it to the Jir only, and for thefe laft three 
weeks have obferv'd its motion as affedted by the Moif^ 
cure and Drought thereof, audi find it to obey the al- 
terations thereof moft nicely; there falls not the leafl 
ftiower, at which it dos not prefently twift ; and when by 
rifmg Clouds a fair day becomes overfliadow'd, the Cord 
-is immediately fenfible thereof, and again as fenfible of 
their Vanifliing and alteration to fair Sun-fhine. So that 
1 have feen it Ihew alteration, whe^n not the leaft could 
H h z be 
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