Jeffries, 1786, Narrative of Two Aerial Voyages

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John Jeffries. Two Aerial Voyages of Doctor Jeffries with Mons. Blanchard; with Meteorological Observations and Remarks. The first voyage, on the thirtieth of November, 1784, from London into Kent: the second, on the seventh of January, 1785, from England into France. Presented to the Royal Society, April 14, 1785; and read before them, January 1786. London: printed for the author; and sold by J. Robson, new Bond-Street, 1786.

Online at Internet Archive.

Foreward from WPA edition:

The Book "A Narrative of the Two Aerial Voyages of Dr. Jeffries with Mons. Blanchard; with Meteorological Observations and Remarks, by Doctor Jeffries, London, 1786," is now so rare that the Aeronautical Archives of the Institute of the Aeronautical Sciences, with the cooperation of the Works Progress Administration of New York City, has prepared copies for distribution to libraries and universities so that this interesting and historically important volume may be available and more widely read than heretofore.

Dedicated by Jeffries to Robert Sanderson, Esq. "In grateful acknowledgment of the generous friendship afforded by him, both professional and personal; as well as for his ingenious hints respecting such experiments".

Jeffries writes that he would have submitted the work publicly to begin with, but for the invitation of Joseph Banks to present them to the Royal Society, "that they might afterwards be ushered into the world under the sanction of those distinguished Judges and Patrons of Philosophical Discoveries and Experiments."

The book includes a Procès Verbal, in French, for each of the ascents, with names of witnesses including the French ambassador (at the first).

First voyage

Jeffries' meteorological data from 30 November 1784, reprinted in the book.

Jeffries relates that a payment of one hundred guineas convinced Blanchard to bring him along, and that, since he had no experience with ballooning, he would be free to make meteorological observations. He mentions the difficulty of finding a launch site:

The disorder and mischief occasioned by two unsuccessful attempts, and the damage thereby done to individuals in their property, had made every one who had grounds of their own, or at their disposal, suitable for such an exhibition, in or near the metropolis, resolve against granting the use of them, on almost any consideration; and more thanfour weeks were lost in fruitless solicitations for a proper place to ascend from. (p. 12)

He realized in retrospect that it's better to avoid buildings as much as possible during takeoff, because the need to ascend vertically leads the balloonists to carry less ballast and make an unnecessarily sharp ascent. (29–30)

He took barometer, thermometer, electrometer, hydrometer, clock, and compass. He also brought vials in which to store air samples. And a notebook.

He writes that Blanchard threw out "quarto pamphlets" over the city. (p. 17) Jeffries wrote four post-cards, addressed to friends, which he threw out of the car. Three of these were forwarded and received. (p. 18)

Second voyage

File:Blanchard Jeffries column.png
Column erected to Blanchard & Jeffries in the Forest of Guînes, France, where they landed after crossing the English channel on 7 January 1875.

Blanchard and Jeffries left London on 17 December 1784 but weren't able to make a launch until January. In the mean time, writes Jeffries, various ill-wishers had attempted through subterfuge and trickery to stop Blanchard from taking him along. (pp. 40–41)

On this expedition Jeffries took only barometer and compass.

Soon after ascending (27" on the barometer) "we began to have overlook and have an extensive view of the coast of France; which enchanting views of England and France being alternately presented to us by the rotary and semicircular motion of the Balloon and Car (a circumstance mentioned in our former experiment) greatly increased the beauty and variety of our situation." (43)

About 3/4 of the way across they were sinking rapidly and had to jettison nearly everything, including anchors, ropes, and clothes. When they reached French airspace they were higher than they'd ever been, and they flew for a while above the forest. Relieving themselves off the side of the ship, Jeffries believed, made the difference in allowing them to clear the tree tops. (48)

Also:

[...] I cannot but mention here, that amidst all the magnificent and extensive scenes under and around me, nothing at the time more impressed me with its novelty, than (if I may be allowed to use the expression) the awful stillness or silence with which we seemed to be enveloped; which produced a sensation that I am not able to describe; but which seemed at the time to be a certain kind of stillness (if I may so express it) that could be felt.


Original title A narrative of the two aerial voyages of Doctor Jeffries with M. Blanchard, with meteorological observations and remarks, presented to the Royal Society
Simple title A narrative of the two aerial voyages of Doctor Jeffries with M. Blanchard, with meteorological observations and remarks, presented to the Royal Society
Authors John Jeffries
Date 1786
Countries GB
Languages en
Keywords John Jeffries, Jean-Pierre Blanchard, voyage, meteorology, observation, ascent, LTA, balloon, instrument, Royal Society, English Channel
Journal
Related to aircraft? 1
Page count 60
Word count
Wikidata id

Sources

  • Brockett 1910, page 451, entry 6577: Jeffries. A narrative of the two aerial voyages of Doctor Jeffries with M. Blanchard, with meteorological observations and remarks, etc. . . . Presented to the Royal Society, April 14, 1785. London, 1786, 4°, pp. 60, ill. (6577