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about this matter and tryall should be made in the Exhausting
engine to see to wt height it would rise therein, & whether
water would run in A syphon:

After this there was much Discourse about the cause of this effect
. . . . . /whether from pressure inward motion of the water vpon the pipes touching it
or the like/ Mr. Hooke explaind his theory of it and Indeavou
red to show the Reason thereof from the congruity of the bodys fluid
bodys wth. the solid, But it was Disired some farther experiments should cleer it-

After this Discourse & Debate was ended mr. Henshaw read e 2d
section of Sr. Francis Bacons naturall History which concer
ned the . . . internall motion of bodys. Entitled of motion vpon pressure
wherevpon the first experiment was debated, mr. Hooke Related that he had ob
serued that the motion of the glasse was vibratiue perpendicular to the surface
of the glasse and that the circular figure changed into an ouall, one way
and the reciprocation presently changed it into an auall the other way, which
he discouerd by the motion of the waters vndulation or rising of the
water in the glasse which he obserued to be in 4 places one opposite
of the surface in a square posture. It was moued that the experiment
should now be tryd before the Society. which was accordingly done but
that figure was not soe very plaine but that some doubted it but
Sr. Christopher Wren comming in Said that the glasse would vibrate
much stronger by the being struck on the edge wth. a viol bow. this
was also tryed and then the square vndulation was exceedingly plaine
But there was also Discouerd an other vndulation by wch. the water
was obserued to rise in 6 places like a hexagone and vpon
further tryalls also in an 8 places like an octogone, each of
these gaue their Particular & Distinct Sounds the 4 & 8 were
octaues & the 6 & 4 were fifths. the further examination of
this was left to the next meeting.

Ref: CELL/RS/HF_453  © Centre for Editing Lives and Letters