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Airopaidia : $b Containing the narrative of a balloon excursion from Chester, the eighth of September, 1785, taken from minutes made during the voyage; hints on the improvement of balloons ... To which is subjoined, mensuration of heights by the barometer, made plain; with extensive tables. The whole serving as an introduction to aërial navigation.Baldwin, Thomas

History

Airopaidia : $b Containing the narrative of a balloon excursion from Chester, the eighth of September, 1785, taken from minutes made during the voyage; hints on the improvement of balloons ... To which is subjoined, mensuration of heights by the barometer, made plain; with extensive tables. The whole serving as an introduction to aërial navigation.

Name: Airopaidia : $b Containing the narrative of a balloon excursion from Chester, the eighth of September, 1785, taken from minutes made during the voyage; hints on the improvement of balloons ... To which is subjoined, mensuration of heights by the barometer, made plain; with extensive tables. The whole serving as an introduction to aërial navigation.
Author: Baldwin, Thomas

Baldwin, Thomas

Aeronautics -- Early works to 1900; Balloons -- Early works to 1800

1st. _To subtract the lower Barometer from the upper. Then,_

2dly. _By the_ 3d Column _of the same Table, find the_ +difference+,
(_viz. of_ one _or_ two Tenths _at the most_) below _the Inches and_
nearest Tenth _of the_ lower _Barometer_.

_And_ lastly, _with that_ +difference+, _find by the_ 3d Table, _the
Height at the Standard-Heat, corresponding to the remaining Decimals_
above _the_ upper _Barometer_.

421.(_1st._) From the lower Barom. viz. 30.082
             Subtract the upper         29.9865
                                        ———————
  Remaining Decimals _above_ the upper    .0955

_2d._ Find, by the 2d Table, the Height corresponding to the Inches,
and _nearest_ Tenth _above_ and _below_ the Point at which the
Quicksilver rests in the lower Barometer.

  The Inches and _nearest_ Tenth is
     _above_ 30 Inches, correspond. to Feet 1681.7
  and _below_ 30.1, corresponding to        1595.0
                                            ——————
                                              86.7
  which is the +difference+ of .1 _below_ 30.1.

_Lastly._ Find, by the 3d Table, _with_ the +difference+, viz. 86 Feet,
_on_ the remaining Decimals, for the Height, in Feet, corresponding to
the Standard-Heat.
     viz. .09     77   = 77. Feet.
          .005    43   =  4.3
          .0005   43   =   .43
                         —————
  Answer, Height in Feet 81.73
corresponding to .0955 above Inches 29.9865 Tenths of an Inch, of
Quicksilver in the upper Barometer thus brought to the Standard-Heat.

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