_large Pipe_, in comparison of those I formerly mentioned; for I could
observe the _progress_ of a _very deep ting'd liquor_ in it with my _naked
eye_, without much trouble; whereas many of the _other pipes_ were so _very
small_, that unless in a _convenient posture_ to the light, I could not
perceive _them_:) But 'tis very probable, that a greater _patience_ and
_assiduity_ may discover the liquors to _rise_, at least to remain
_suspended_, at heights that I should be loath now even to _ghess_ at, if
at least there be any _proportion_ kept between the height of the ascending
liquor, and the _bigness of the holes_ of the pipes.

_AN ATTEMPT FOR THE EXPLICATION OF THIS EXPERIMENT._

My Conjecture, _That the unequal height of the surfaces of the water,
proceeded from the greater pressure made upon the water by the Air without
the Pipes_ ABC, _then by that within them_[8]; I shall endeavour to confirm
from the truth of the two following _Propositions_:

The first of which is, _That an unequal pressure of the incumbent Air, will
cause an unequal height in the water's Surfaces_.

And the second is, _That in this experiment there is such an unequal
pressure_.

That the first is true, the following _Experiment_ will evince. For if you
take any Vessel so contrived, as that you can at pleasure either _increase_
or _diminish_ the _pressure_ of the Air upon this or that part of the
_Superficies_ of the _water_, the _equality_ of the height of those parts
will presently be _lost_; and that part of the _Superficies_ that sustains
the _greater pressure_, will be _inferior_ to that which undergoes the
_less_. A fit Vessel for this purpose, will be an inverted Glass _Syphon_,