( 5t/2 ) 
.Notion, as it is there lofertcd : And, whether he have fioce 
had leifurc, amidft a gr^at prcfs of other buGoefi^ to purfuc 
ity I anoii]ot certain. 
Now, though I would not wholly exclude this, if fuch 
ftiall be found to be (but only fufpcnd my Aflent till it be 
evinced 5 ) yet furely there muft be foroewhat more in it 
than that of this Subtile matter , to folve iht Th£nomenon^ 
notwithftanding the two Experiments now alledged by 
MMyg^vs in favour of it. For, if this Matter be fo fubtile 
as to prefi, through the top of the Glafs , upon the Quick- 
filver (and confequently through the upper upon the nca- 
ther of the Wo- Mar bleff) zs is acknowledged 5 (and with- 
out which it is no more able to precipitate the Quickfilver 
while impurej and when it is in part lubfided, than when it 
is pure, and the Tube top full :) I do not fee, why it fliould 
;npt balance it felf (above and below ) in the fame manner 
.asCommon Air would do, if the Tube were pervious to 
it at both ends, and the Quickfilver, by the preponderance 
of its own weight, fall prefently. 
And the^^er , That, though the Glafs be penetrated 
by it, yet not in fo copious a manner as where no Glafi is 5 
doth nor, to me, folve the difficulty : Becaufe the fame ob- 
'ftacledoth juft in the fame manner remain, when the Tube 
is in part emptied^ and,when the Quickfilver is un-purged: 
the pores of the Glals not being, by either of thofe, made 
more open or more pervious. And if we fuppofe the Sub- 
tile matter by percolation to be ftrain'd through , with 
fome difficulty^Cas Air or Water would be through a cloth,) 
this might poflibly caufe the Quickfilver, when it does 
fiok, to RokgraduaSj/ J but not (as we fecit,) fuddeftly to 
fall to the height of 29 Inches 5 as from D to I. 
The Connexion or Gohaefion of the parts of Quickfilver, 
.either each to other , or to the fides of theGlafi, which 
'MtMugens fuppoicth to require for their feparation a great- 
er force, than is in thefe percolated particles till they have 
room made for them to combine 5 feems to me the lefscon- 
fiderable, becaufe it is not fo nece0ary to feparate them 
from 
