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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

_First_, _with_ 4° _on_ 29 Inches = .0117:
  _2d_, _with_ 4° _on_ .5218 Tenths _above_ 29 Inches:
  In order to obtain which, begin
                    _with_ 4° _on_ 29 = .0117
               then _with_ 4° _on_ 30 = .0121
  Subtract for the Expansion _with_     —————
  4° _on_ 1 Inch above 29, and there
  remains                               .0004.

[Sidenote: Section 362.]

Then for the Expansion _with_ 4° _on_ .1 Tenth of an Inch above 29
Inches; add a Cypher and
  decimal Point, viz.             .00004:

[Sidenote: Section 363.]

  Then for the Expansion on       .5128, multiply
  the two last Terms, and divide  —————
  the Product by the first Term
  .1: the Answer is               .0002|0872
  Add the Expansion _with_ 4° _on_
    29 Inches, just found,        .0117
  to the Inches of the _colder_
    Barometer,             viz. 29.5218
                                ———————
                 Answer; Inches 29.5337 Tenths of the _colder_
Barometer, are _now_ expanded equally with the _warmer_: (rejecting the
Decimals as in Section 395.)

Place the Barometers, thus:
  _Upper_ Barometer, 29.5337
  _Lower_ Barometer, 30.0168

                       _End of the first Stage._

[Sidenote: Section 371.]

411. _By the 2d Table_, and in the 2d Column, find the _Height_ of
each Barometer, _with_ the _Standard-Heat_, in Feet and Tenths,
corresponding to the Inches and +nearest+ Tenth _above_ and _below_ the
Point required: and
  First of the _upper_, at 29.5337:
  The Inches and _nearest Tenth_ is above
                          Feet.
        29.5, corresp. to 2119.7 } Difference
  and below 29.6, cor. to 2031.5 } between .5 and .6
                          —————— } above 29 Inches.
                           88|.2 }

[Sidenote: Section 373.]

412. _By the 3d Table_, _with_ the _Difference_ 88 Feet, find the
_Expansion_ on the remaining Decimals, above 29.5, viz. on .0337, thus:
  on 03   = 26 decimated 26.
     003  = 26            2.6
     0007 = 62             .62
                         —————
                    Feet 29.22

  From the _Height_ corresponding to        29.5
  viz. Feet  2119.7 Tenths,
  subtract the 29.22, i.e. Height cor. to     .0338
  and there —————————                       ———————
  remains    2090.4|8, the _Height_ cor. to 29.5338
  with Expansion of the Standard-Heat.

413. Repeat the 4 last Steps for the _lower_ Barometer, at 30.0168.

  1st. The Inches and _nearest_ Tenth is _above_
      30. corresp. to Feet 1681.7 } Difference of
  and _below_ 30.1 cor.    1595.0 } .1 above 30
                           —————— } Inches.
                            86|.7

2d. Then with 86 Feet, find the _Expansion_ on the remaining Decimals,
above 30,
  viz. .0168, thus: on 01   =  9   9.
                       006  = 52   5.2
                       0008 = 69    .69
                                  —————
                             Feet 14.89

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