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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

422. Prepare for Expansion of Air from Excess above Standard-Heat, on
the same Number of Feet:
      Detached Thermom. _above_   76°.
      Detached Thermom. _below_   68.0
                                  ————
        Whole Heat               144.0
        Half Heat                 72.0(0 adding a Cypher)
        Standard-Heat             31.24
                                  —————
  which deduct, and there remains 40.76: with which, by the 4th Table,
  find the Expansion of Air on Feet 81.73:
  _First, with_ 40°, _on_ 81.73, thus:
    _on_ 80.    as 8000 – 777.6 = 7.776
          1.    as 1000 –  97.2 =  .0972
           .7   as 7000 – 680.4 =  .06804
           .03  as 3000 – 291.6 =  .002916
                                  ————————
                                  7.944156
  _Second_, _with_ .76 _on_ 81.73, thus:
    _on_ 80.    as 8000 – 1477.4 = .14774
          1.    as 1000 –  184.6 = .001846
           .7   as 7000 – 1292.7 = .0012927
           .03  as 3000 –  554.0 = .0000554
                                   ————————
                        Expansion  .1509341
  add the former Expansion        7.944156
                                  —————————
  Sum of the Expansions, viz. }
    Height in Feet            }   8.0950901
    from Excess of Heat above Standard,
  _with_ 40°.76 _on_ 81.73,
  +added+ to the Height at the Standard-Heat, }
  in Feet                                     } 81.73
  gives, in Feet and Tenths, the true           ——————
    Height of the Tarpeian Rock                 89.8|2.




                            CHAPTER LXXIX.


A CALCULATION TO ASCERTAIN THE HEIGHT OF THE BALLOON ON THE DAY OF
  ASCENT: ONE BAROMETER AND ONE THERMOMETER ONLY, BEING TAKEN UP INTO
  THE CAR.

Section 423. The Question is stated from Section 36: and the Mode
of Operation taken from the _Recapitulation_ of the second Example,
Section 409.

Observation before the Ascent:

Below: Barometer 29.8; attached Thermometer 0; detached Thermometer 65°.

Above: Barometer 23¼ = 23²⁵⁄₁₀₀ or 23.25;[135] attached Thermom. 0;
detached Thermom. 65°.

There being no attached Thermometers; the _first_ Table is useless: the
Barometer below is therefore supposed to be of the same Temperature as
when above; the detached Thermometer remaining at the same Degree, viz.
65°.

  State the Barometer, thus: when _below_, at 29.8
                             when _above_, at 23.25.

                       _End of the first Stage._

424. Find the Height (at the Standard-Heat) corresponding to the Inches
and _nearest_ Tenth above and below 23.25: i.e. above 23.2, and below
23.3: by the 2d Table.

Now 23.2 corresponds to 8379.7: and the Difference of .1 above, i.e.
to 23.3, is in Feet = 112|.1: by the 3d Column of the same Table.

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