J. L. BELL is a Massachusetts writer who specializes in (among other things) the start of the American Revolution in and around Boston. He is particularly interested in the experiences of children in 1765-75. He has published scholarly papers and popular articles for both children and adults. He was consultant for an episode of History Detectives, and contributed to a display at Minute Man National Historic Park.

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Tuesday, August 01, 2006

Dr. John Jeffries: physician, Loyalist, aeronaut, part 4

The first of this series of postings described how Dr. John Jeffries is sometimes called the first American to fly, even though he didn't see himself as an American at the time, but rather as a loyal British subject. It was 30 Nov 1784, and Jeffries and the French balloonist Jean Pierre Blanchard had just taken off from the Rhedarium Garden in London, as described in yesterday's posting.

Dr. Jeffries thought that the early reports of aerial voyages lacked scientific rigor, with balloonists describing their feats and their sensations rather than measuring the atmosphere objectively. Therefore, he had equipped Blanchard's hydrogen balloon with some of the most advanced instruments available:

  • thermometer, for measuring temperature
  • barometer, for measuring air pressure (which, of course, varies with altitude as well as weather)
  • hydrometer, for measuring humidity
  • electrometer, for measuring electrical activity
  • timepiece
  • compass
  • telescope
  • thin ribbon, with scissors and knife for cutting it, to throw out and see whether the balloon was going up or down
  • several small glass bottles filled with distilled water and sealed
  • a "little dog"
  • a notebook and silver pencil, which he judged to be less likely to be affected by the thin air than either a pen or an ordinary pencil.

One of the aeronauts' first experiments, however, was to try Blanchard's invention of oars, wings, and rudder to steer the course of the balloon. (This apparatus appears in the illustration above.) Blanchard had a good idea, in theory: being to direct the course of a balloon would make it much more useful for transportation and warfare. However, the force of wind on a large balloon was far stronger than anything two men could counteract with artificial wings. Jeffries still insisted the experiment was a success:
M. Blanchard applied himself to the oars, which he had made some experiment of on our first ascent, and which (though inadequate to the government of the Balloon) appeared to me very materially to influence the course, ascent, and progress of the Balloon; and with which we could, by acting with but one oar or wing, always turn round the Car and Balloon.
In other words, the men found they couldn't steer their balloon, but could twist in the wind.

Jeffries noted down many measurements of the thermometer, barometer, and hyrdrometer. As to the electrometer, he wrote that its indicator "Though frequently attended to, I never observed to be any ways affected" by the altitude. By pulling the stoppers of the little glass bottles, he filled them with air from the various altitudes, then sealed them up again. He also tried to track the path of the balloon. For instance, at 2:59 PM:
we passed over what appeared to me to be a pavement; but which, upon examining with my prospect-glass, I was surprized to find, were the tops of a forest or wood. . . . Mr. Blanchard threw out a few more of his pamphlets; and I, at this time, amused myself in writing four cards, addressed to some friends; each of which I attached to an handkerchief, and at different periods afterwards cast out of the Car; and have since had the pleasure to know, that three of them were taken up at different places, and kindly forwarded, and received by those to whom they were addressed. . . . The extensive grounds of a Callico-Printer, covered with cloths of various colours, at my first observing it, appeared like a bed of tulips, which, when I remarked to M. Blanchard, he was struck with the same idea.

At about 3:20, the balloonists began to suffer from the cold, as did the dog. The men prepared to descend: "we untwisted both tubes of the Balloon, (through which it had been filled with gaz) and put them without-side of the Car, and opened the valve, to ease the Balloon, and to favour our descent.” But after five minutes, the temperature rose back into a comfortable range, and they decided to continue their journey. “We now refreshed ourselves with cold chicken, and drank a few glasses of wine to the health of our friends below us.” The balloon passed over Dartford and Crayford. Blanchard and Jeffries then decided that they had let out too much gas and might land in the river below. The doctor wrote, "We then threw out every thing except my instruments and our cloaths; and though this visibly checked our descent, yet it had no effect on our motion, in a right line for the River.” I must note that his account never mentions the little dog after this point.

The landing was rough:
At about 50 minutes past three, we cast out one of the anchors, or grapnels, and in two minutes after, the second, which as soon as it touched the surface of the earth (the cords by which they were attached to the net over the Balloon being 50 yards in length) checked us so far, that we struck the ground lightly, but rebounded; and ascending again, we opened the valve; but passing between the tops of some trees, they forced off, and carried away from the Car, our moulinet, with one of the oars or wings; indeed we met with such resistance, as to break off many of the twigs and berries, and to force some of them into my cloaths, pockets, &c. I caught hold of the limb of one of the trees, in hopes of stopping our motion, but was unable to do it; and was forced, after exerting my utmost efforts, to let it go. . . . As soon as we had passed the trees, the wind blowing fresh, our anchors were every minute taking the ground, so as to check us, and then giving away, so that we alternately fell and rose; when a man, by hard running, got hold of one of the cords of our anchors, but could not stop us: On which we opened the valve as far as it was possible, and kept it open until several persons coming up with us, and seizing hold of both the anchor cords, stopped our progress; and we alighted exactly at 59 minutes after three, in a marshy piece of ground, within a few yards of the River.

Legend says that a couple of years before some French farmers had attacked and destroyed a balloon that landed in their neighborhood, thinking it was a demon, but by this point ballooning had apparently been publicized enough that the English farmers knew what they had witnessed. The locals who had helped bring down the balloon were very excited, "asking thousands of questions." Jeffries found "a few bits of chicken, and morsels of bread" in the car; "I, at their urgent requests, divided it almost into atoms among them; every one being eager to get some of that food, which they had seen literally descend from the clouds.” Jeffries himself needed “a bowl of warm tea” to recover his equanimity, though his arms remained sore “for a day or two afterward.”

Blanchard and Jeffries soon began planning for a second, even more impressive voyage: the first aerial crossing of the English Channel. (Take off to Part 5.)

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