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mr. Hooke then gaue an account of some experiments
he had made wth. mr. Hunt & mr. Crawley at the Piller
on fish street hill. concerning the Difference of the pres=
sure of the air at the top & Bottom of the Column
there and at seuerall Intermediat stations. And affirmd
that he had found the quicksiluer in the tube to stand
higher ^ /at the bottom of the column/ then at the top of It by neer a third part of
an inch, and that he had obserued the same to ascend by
Degrees as neer as he could perceiue equall proportionale
to the spaces descended in going down from the top of the
column to the Bottom. But because the said station
of the mercury were distant from one another but very little
and soe it was not easy to Determine the certaine propor
tions of the one to the other therefore he Propounded
against the next Day an Experiment to be tryd
at the same-place wth. an Instrument which would
Determine that Difference to A 1000 /hundred/ times more exact
ly . which Instrument also he there produced in or=
der to explaine the manner thereof, It being made vpo
the same principle wth. the wheel barometer but
more curiously w wrought.

The experiments wth this Instrument were appointed
to be tryd at the Column, vpon Thursday next
Eleauen of the clock.-

[In margin]perused  

Ref: CELL/RS/HF_211  © Centre for Editing Lives and Letters