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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

414. (3d.) From the _Height_ corresponding to
  30 Inches, viz. Feet 1681.7 Tenths,
  subtract the Height    14.89 corresp. to .0168,
                       ———————
  and there remains    1666.8|1, the Height corresp.
  to 30.0168, with _Expansion_ of the Standard-Heat.
  4th. From the _upper_ Height, at 2090.48
  Subtract the _lower_ Height, at  1666.81
                                   ———————
  And there remains the Height      423.67 in Feet
  and Tenths of the upper Barometer, with the
  Standard Temperature.

                      _End of the second Stage._

[Sidenote: Section 374.]

415. Detached Therm. _above_      57°
     Detached ditto, _below_      60.2
                                ———————
        _Whole_ Heat             117.2
        _Half_ Heat               58.6(0 adding a Cypher)
        _Standard_ Heat           31.24
                                 ——————
  which being deducted, leaves 27°.36, viz. Degrees
  of Heat more than the _Standard_, for each Barometer.

[Sidenote: Section 380.]

416. By the 4th Table, find the Expansion of Air, with 27°.36, on Feet
423.67 Tenths.

[Sidenote: Section 406.]

_First_, _with_ 27°, _on_ 423.67, thus:
  viz. _on_ 400  as 4000 = 262.4 decimated 26.24
           20    as 2000 = 131.2            1.312
            3    as 3000 = 196.8             .1968
             .6  as 6000 = 393.6             .03936
             .07 as 7000 = 459.2             .004592
                                           —————————
                               Expansion = 27.692752

[Sidenote: Section 407.]

_Second_, _with_ .36 _on_ the _same_, thus:
  on 400    as 4000 = 349.9 decimated .3499
      20    as 2000 = 174.9           .01749
       3    as 3000 = 262.4           .002624
        .6  as 6000 = 524.8           .0005248
        .07 as 7000 = 612.3           .00006123
                                      —————————
                          Expansion = .37050003
                     Add the former 27.692752
                                    ———————————
                     Height in Feet 28.06325203

417. Which Height for Expansion of Air, _with more than_ the Standard
Heat, being +added+[133] to the Height, for Expansion of the Barometer,
_with_ the Standard-Heat, gives the true Height of the upper Barometer,
at the given Heat.

  For _Expansion_ of _Air_ above Standard Heat,
                            Height in Feet   28.0
  For _Expansion_ of _Barometer_,
    with Standard:         Height in Feet   423.6
                                            —————
  418. True Height of the _upper_ Barometer 451.6
  _Lower_ Barometer 1 Foot above the Water    1.0
  Height of the Top of the Cross above the
    Gallery                                  50.0
                                            —————
  Height of the Top of the Cross above the
    Tyber                                   502.6

  Height of the same, measured the same
    Day geometrically, was             Feet 502.9

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