C yy^ l 
i ta parcs contracfted and clofer put together , which feems 
probable, for that for Example', the G^ckfilver then p- 
mits , and fqueezes out freih particles of y/ir into the 
Tu.be^ which increafing the £2^//^of the ^ir, and confe-^ 
quently its Elafiictty.^ the glutei^ ilveT is neceffarily de- 
preffed thereby, that is, by an external force or power; 
And alfo the ^tc^ilver muft of it leif come clofer toge- 
ther in its own internal parts, that is, defcend for both 
reafons. : ■ - i „:,. v. . L.h 'J../ 
Andthat niuch^r ismixtwith it, appeai^s from the 
Application of a heated Iron to the Tube, as is pradiced 
in the purging of it that way ; and alfo fox that 
/r£?72 will ruft though immefft in it, as fome Philofophdrs 
have lately obferved. i 
Now whether the^?V^^7i/(?r rifes in the Pipe ( which 
it certainly does in hot, and frofty weather j it may then 
be faid to be in a Natural ftate, free open aud expanded 
like it felf, which it feems it ever is within t e Tro^fr^j, 
and with us only in very hot, and very frofty weather. 
But when it delcends, it is then \:ontrad:ed , and as it 
were convulfed and drawn tDgether, as it moftly is in our 
Climate of England^ and more or leis, as we guefs 5 in all 
places on tills fide the Tro^/V/^J". Which contradion 
plainly appears from the Concave figure of both Super- 
ficies^ not only in that qf the ^iehsilver in theT-^^f , but 
alfo f if well obferved J in that which ftagnates in the 
Pot, ortoffi itielf 
The difficulty feems to lye in the reconciling the fame 
effed: of the ^^V^^/^/t^rrV rifing in t\\Q srube^ hom iuch 
feemingly diffenng caufes, as great heat and iatenfe 
Froft, and thofe who fliall willingly affent to us in one 
particular, and grant us warmth, as a probable caofe of 
Its Reftitution to its Nature, will yet be at a ftand, how 
to imagine, that great Froji likewife lliould bring the 
§luiksilver nearqr its own Naturae too ; I aiifwer, that Salts 
liquified will coagulate or Criftallize, that is, will return 
C to 
