188
or any other gro
sse fluid tho
se proportions would hold very neer
yet,
w In a medium wherein there was a re
si
sting fluid body it
would not hold in any wi
se especially in tho
se which had a consi
derable proportion of specifique Grauity to that of the
De
scending body. Hence he said was the Rea
son why a down
feather being Lett fall in the air, would de
scend therein if it
were not Di
sturbed by an aequall Degree of velocity. But
on the contrary if the said feather were Let fall in a
medium whence all the air was exhau
sted and nothing but
A fluid ether left he affirmed the same would fall therein
as to sen
se w
th the same /accelerated/ velocitys that a stone would doe in
the open air. this He affirmed he had formerly shewd to
his maie
sty at whitehall. But that vpon the admitting of
the air into the space through w
ch. the feather was to
De
scend the same was plainly seen to Descend w
th an aequall
degree of velocity the whole space which was all the way very
slow. He further added that In Vacuo the De
scent of all
bodys was aequally swift increasing continually its velocity
by a duplicate proportion to
the time of continuance but
that in all grauitating mediums somew
t. of that proportion
is impeded. Hence he affirmed that in the Exp
ts. tryed from
the top of S
t. Paules steeple It was very plainly visible
that a Leaden ball would De
scend fa
ster then
. . . one of the
same bigne
sse of wood, and that of wood fa
ster then
one of cork. insoemuch that the heauie
st would in that
De
scent get neer 30 foot before the other at the bottom
He further added al
so that euen of Bullots of the same sub
stance
the bigger would manife
stly out run the le
sse in their descent
As al
so that all mediums whatsoeuer had some Resi
stance to
the motion of bodys through them. and that euen tho
se w
chhad
les Lea
st, had yet a very considerable opposition to
a motion that were proportionally Accelerated. Hence
It was that Birds were able to su
steine themselues in
the air, and that one might break the stronge
st oar
by swiftly striking it /against/
. . .. the water
Ref: CELL/RS/HF_190 © Centre for Editing Lives and Letters