Archimedes Texts

128
ther, will gather up all the little bubbles,
and unite them with itself into one great
one, so that if by reinverting the Tube
you let that bubble return to the open
end of it, you will have a much closer Mer
curial Cylinder then before, and need but
to adde a very little Quick-silver more to
fill up the Tube exactly. And lastly, as for
those lesser and inconspicuous parcels of
Air which cannot this way be gleaned up,
You may endeavor before you invert the
Tube, to free the Quick-silver from them
by shaking the Tube, and gently knock
ing on the out-side of it, after every little
parcel of Quick-silver which you pour in;
and afterwards, by forcing the small la
titant bubbles of Air to disclose them
selves and break, by imploying a hot Iron
in such manner as we lately mention'd. I
remember that by carefully filling the
Tube, though yet it were not quite free
from Air, we have made the Mercurial
Cylinder reach to 30 Inches and above an
eighth, and this in a very short Tube:
which we therefore mention, because we
have found, by experience, that in short
Tubes a little Air is more prejudicial to
the Experiment then in long ones, where
the Air having more room to expand it