Benjamin Franklin Papers

From Benjamin Franklin to Joseph Banks, 30 August[–2 September 1783]

To Joseph Banks

LS:5 Royal Society; press copy of LS: Harvard University Library; AL (draft): University of Pennsylvania Library;6 copy: Library of Congress

During August, while Etienne Montgolfier was conferring with the Académie des sciences, working on his new balloon, and pursuing his business interests as a papermaker,7 his competitors were scrambling to figure out how they could safely generate the 900 cubic feet of hydrogen needed to fill the globe they had constructed, financed through private subscription.8 It is unlikely that Franklin was among the subscribers, as he makes no mention of it in this report. (By contrast, he did tell Banks in October that he had subscribed to Charles’s next experiment.)9 He certainly was acquainted with Faujas de Saint-Fond, however, who managed the subscription, and knew Charles by reputation and in person, having attended at least one of his lectures.1

By August 23, when materials for Charles’s balloon were finally ready and Paris was “in an uproar about the flying machines,” the press had begun alerting readers that a public demonstration of the rival balloon was imminent.2 On August 25 all of Paris (according to one reporter) made its way to Charles’s home on the place des Victoires, where people glimpsed the marvelous globe aérostatique suspended. It was transported under escort to the Champ de Mars in the middle of the night of August 26–27. As soon as it was properly situated and anchored, the team of scientists and assistants began the laborious generation of hydrogen. By the time the globe rose “majestically” from its moorings at five o’clock in the evening, the size of the crowd exceeded anything most witnesses had ever seen.3

Even in the midst of the overwhelming “enthousiasme public,” however, there were enough detractors that their grumblings were reported along with the machine’s success. Where would this lead, they asked. What possible utility could be derived from these experiments? When this question was posed to Franklin on the day of the demonstration, he was said to have replied, “Eh! à quoi bon l’enfant qui vient de naître?” (“Eh! Of what use is a new-born baby?”)

This famous bon mot was recorded by Baron von Grimm in his Correspondance littéraire, a handwritten paper circulated privately to a select group of European aristocrats. Grimm went on to observe that the infant might die in his cradle or perhaps turn out to be an “imbécile,” but he might equally turn out to be the glory of his country, the light of his age, the savior of humanity.4 A few weeks later, after the next balloon ascension inspired a frenzy of new commentary, Franklin would see his witticism quoted in the mainstream press in slightly altered form and become transformed over time, as elements of Grimm’s own comments were incorporated and the phrase was embellished and burnished.

The wit of the original version, whose essence lay in its being posed as a rhetorical question, was flattened when the quip appeared publicly for the first time in the Mémoires secrets on September 24: in this retelling, Franklin “ingeniously” replied, “C’est l’enfant qui vient de naitre.” This phrase was printed the next day in the Journal de Paris.5 In the September 27 issue of the weekly Mercure de France (Journal politique de Bruxelles), the “penseur profond” was quoted as saying, “Peut-être sera-t-il un imbécile ou un homme de beaucoup d’esprit; attendons pour le juger que son education soit achevée.”6 It was in this distorted form that the expanded phrase appeared twice more in other journals with widespread distribution, to the indignation of an earnest inventor from Picardy whose objections filled two long letters.7

Franklin’s mot continued to circulate as the balloon craze grew and the expense of the trials kept alive the question of whether glorified kites could be justified in light of society’s pressing needs.8 Balloons and babies became so closely associated, in fact, that both enthusiasts and skeptics used the metaphor, with or without attribution, either to support their views or to cast ridicule on the entire phenomenon. Thus, Lettre de M. Joly de Saint-Vallier … à Madame La Princesse de ***, à Pétersbourg, sur les ballons appellés globes aëro-statiques, published in Ostend in November, declared that the balloon was an infant that had already reached maturity and would never be anything but a toy. A reviewer, explaining the allusion, combined previous versions into a smoother formulation. “Le mot célebre de M. Francklin,” he explained, was “Ce n’est encore qu’un enfant: peut-être ne sera t-il qu’un imbécille, peut-être deviendra-t-il un grand homme.”9

Even Franklin played off the remark, it seems, after witnessing Charles’s manned flight on December 1. Enchanted at the sight (according to the Mémoires secrets), he said that the first balloon had been an “enfant,” but this one was a “géant.” Not wanting to appear partisan, however, he added that “le machine aérostatique étoit un enfant dont M. Montgolfier étoit le pere & M. Charles la mere nourrice.”1

Franklin also invoked the metaphor when shrugging off a question posed to him by Condorcet at a session of the Académie des inscriptions et belles-lettres in November. When asked if he thought it would ever be possible to steer a balloon, he was quoted as saying: “la chose est encore dans son enfance, ainsi il faut attendre.”2 Why would a chronicler preserve such an unremarkable statement if not for its allusion to the by-then famous expression?

In the present letter reporting on the events of August 27, Franklin gives Joseph Banks a sense of the crowd’s speculations and begins to muse on the implications of the balloon experiment. But neither here nor in any other letter does he so much as allude to the witticism for which his name was yet again being celebrated, concurrently with the peace treaty and the image of the United States as an infant emerging from its cradle that was circulating around Europe on his Libertas Americana medal.

Did Franklin actually utter this mot, and if so, in what form? Sixteen years after the fact, and nine years after Franklin’s death, a speech delivered by Le Roy confirmed that he had said something of the kind. On 21 Prairial, An 7 (June 9, 1799), when asked by the minister of the interior to report to the first class of the Institut national des sciences et des arts on the utility of the balloon and Montgolfier’s role in its invention, Le Roy reminded his audience of “ce mot de l’illustre Franklin, interrogé par un savant qui lui faisoit la même question sur leur mérite que celle que le Ministre de l’Intérieur a faite à la Classe: C’est un enfant, répondit-il, qui vient de noître, on ne peut pas dire ce qu’il deviendra.”3 This formula certainly captures the meaning, but did Le Roy remember his friend’s exact words? In our view, the rejoinder noted immediately after the fact by Grimm sounds the most Franklinian—succinct, wise, and ironic.4

Passy, August 30.[–September 2,] 1783


On Wednesday the 27th. Instant, the new aerostatic Experiment, invented by Messrs. Mongolfier of Annonay, was repeated by Mr. Charles, Professor of experimental Philosophy at Paris.

A hollow Globe 12 feet Diameter was formed of what is called in England Oiled Silk, here Taffetas gommé, the Silk being impregnated with a Solution of Gum elastic in Lintseed Oil, as is said. The Parts were sewed together while wet with the Gum, and some of it was afterwards passed over the Seams, to render it as tight as possible.5

It was afterwards filled with the inflammable Air that is produced by pouring Oil of Vitriol upon Filings of Iron, when it was found to have a tendency upwards so strong as to be capable of lifting a Weight of 39 Pounds, exclusive of its own Weight which was 25 lb, and the Weight of the Air contain’d.

It was brought early in the Morning to the Champ de Mars, a Field in which Reviews are sometimes made, lying between the Military School and the River. There it was held down by a Cord till 5 in the afternoon, when it was to be let loose. Care was taken before the Hour to replace what Portion had been lost, of the inflammable Air, or of its Force, by injecting more.

It is supposed that not less than 50,000 People were assembled to see the Experiment. The Champ de Mars being surrounded by Multitudes, and vast Numbers on the opposite Side of the River.

At 5 a Clock Notice was given to the Spectators by the Firing of two Cannon, that the Cord was about to be cut. And presently the Globe was seen to rise, and that as fast as a Body of 12 feet Diameter with a force only of 39 Pounds, could be suppos’d to move the resisting Air out of its Way. There was some Wind, but not very strong. A little Rain had wet it, so that it shone, and made an agreable Appearance. It diminish’d in Apparent Magnitude as it rose, till it enter’d the Clouds, when it seem’d to me scarce bigger than an Orange, and soon after became invisible, the Clouds concealing it.

The Multitude separated, all well satisfied and delighted with the Success of the Experiment, and amusing one another with discourses of the various Uses it may possibly be apply’d to, among which many were very extravagant. But possibly it may pave the Way to some Discoveries in Natural Philosophy of which at present we have no Conception.

A Note secur’d from the Weather had been affix’d to the Globe, signifying the Time & Place of its Departure, and praying those who might happen to find it, to send an Account of its State to certain Persons at Paris. No News was heard of it till the next Day, when Information was receiv’d, that it fell a little after 6 a Clock at Gonesse, a Place about 4 Leagues Distance, and that it was rent open, and some say had Ice in it. It is suppos’d to have burst by the Elasticity of the contain’d Air when no longer compress’d by so heavy an Atmosphere.

One of 38 feet Diameter is preparing by Mr. Mongolfier himself, at the Expence of the Academy, which is to go up in a few Days. I am told it is constructed of Linen & Paper, and is to be filled with a different Air, not yet made Public, but cheaper than that produc’d by the Oil of Vitriol, of which 200 Paris Pints were consum’d in filling the other.6

It is said that for some Days after its being filled, the Ball was found to lose an eighth Part of its Force of Levity in 24 Hours; Whether this was from Imperfection in the Tightness of the Ball, or a Change in the Nature of the Air, Experiments may easily discover.

I thought it my Duty, Sir, to send an early Account of this extraordinary Fact, to the Society which does me the honour to reckon me among its Members; and I will endeavour to make it more perfect, as I receive farther Information.

With great Respect, I am, Sir, Your most obedient and most humble Servant

B Franklin

P.S. Since writing the above, I am favour’d with your kind Letter of the 25th. I am much obliged to you for the Care you have taken to forward the Transactions, as well as to the Council for so readily ordering them on Application. Please to accept and present my Thanks.

I just now learn, that some observers say, the Ball was 150 seconds in rising, from the Cutting of the Cord till hid in the Clouds; that its height was then about 500 Toises, but, being moved out of the Perpendicular by the Wind, it had made a Slant so as to form a Triangle, whose Base on the Earth was about 200 Toises. It is said the Country People who saw it fall were frightned, conceiv’d from its bounding a little, when it touch’d the Ground, that there was some living Animal in it, and attack’d it with Stones and Knives, so that it was much mangled; but it is now brought to Town and will be repaired.7

The great one of M. Mongolfier, is to go up, as is said, from Versailles, in about 8 or 10 Days; It is not a Globe but of a different Form, more convenient for penetrating the Air. It contains 50,000 cubic Feet, and is supposed to have a Force of Levity equal to 1500 pounds weight. A Philosopher here, M. Pilatre du Rozier, has seriously apply’d to the Academy for leave to go up with it, in order to make some Experiments. He was complimented on his Zeal and Courage for the Promotion of Science, but advis’d to wait till the Management of those Balls was made by Experience more certain & safe.8 They say the filling of it in M. Mongolfier’s Way will not Cost more than half a Crown. One is talk’d of to be 110 feet Diameter. Several Gentlemen have ordered small ones to be made for their Amusement. One has ordered four of 15 feet Diameter each; I know not with what Purpose; But such is the present Enthusiasm for promoting and improving this Discovery, that probably we shall soon make considerable Progress in the art of constructing and using the Machines.9

Among the Pleasanteries Conversation produces on this Subject, Some suppose Flying to be now invented, and that since Men may be supported in the Air, nothing is wanted but some light handy Instruments to give and direct Motion. Some think Progressive Motion on the Earth may be Advanc’d by it, and that a Running Footman or a Horse slung and suspended under such a Globe so as to have no more of Weight pressing the Earth with their Feet, than Perhaps 8 or 10 Pounds, might with a fair Wind run in a straight Line across Countries as fast as that Wind, and over Hedges, Ditches & even Waters. It has been even fancied that in time People will keep such Globes anchored in the Air, to which by Pullies they may draw up Game to be preserved in the Cool, & Water to be frozen when Ice is wanted. And that to get Money, it will be contrived to give People an extensive View of the Country, by running them up in an Elbow Chair a Mile high for a Guinea &c. &c.


[In Franklin’s hand:] A Pamphlet is printing, in which we are to have a full & perfect Acct of the Experiments hitherto made, &c. I will send it to you. M. Mongolfier’s Air to fill the Globe has hitherto been kept secret; some suppose it to be only common Air heated by passing thro’ the Flame of burning Straw, and thereby extreamly rarefied. If so, its Levity will soon be diminish’d, by Condensation, when it comes into the cooler Region above.

Sir Joseph Banks, Bart.


Calculs du Ballon de 12. Pieds de Dametre
enlevé le Mercredy 27. Aout 1783.

Circonférence du grand Cercle 37. Pieds Diamétre 12. ━━━━ 74 37. ━━━━ Surface 444. Pi. Tiers du Rayon 2. ━━━━ Solidité 888. Pieds cubes. Air atm. à 12. gros le Pi. 12. ━━━━ 1,776. 888 ━━━━ Pesanteur de l’air atm. 10,656. gros ⎰ 8 26 ⎱1332. onces / 16 26,6 52 / 83. lb 4. onces

L’air Atmospherique dont le Ballon occupoit la Place pesant 83. lb 4. ces [onces] et sa force pour s’élever étant de 40. lb il falloit que son Eveloppe et l’air inflammable qu’elle contenoit ne pesassent que 43. lb 4. onces l’Enveloppe en pesoit 25, rèste pour l’air inflamable 18. lb 4. onces.

En supposant le Ballon de 6 Pieds de diametre, son Volume étant le 8eme. du 1er., Le Poids de l’air dont il occupoit la Place sseroit le huitieme de

83. lb 4. onces = 10. lb 6. onces 4. gros
L’air inflammable ⅛ de 18. lb 4. onces = 2. lb 4. onces 4. gros
L’Enveloppe ¼ de 25. lb = 6. lb 4. onces

Les dernieres valeurs reünies sont 8. lb 8. onces 4. gros qui otés de 10. lb 6. onces 4. gros pèsanteur de l’Air atmospherique dont le Ballon occupoit la place, laissent pour sa force d’élevation une Livre quatorze onces.

[In Franklin’s hand:] Sept. 2. I add this Paper just now given me


[Note numbering follows the Franklin Papers source.]

5In L’Air de Lamotte’s hand. BF added the last seven words of the complimentary close and two subsequent notes as indicated. We have silently supplied from BF’s draft one word that was dropped (“an”), and have removed occasional punctuation that conforms to French usage and was inadvertently added by L’Air de Lamotte. Otherwise, the minor copying discrepancies are preserved as written.

6The press copy and AL (draft) lack the second postscript and the enclosure. The complete copy at the Library of Congress contains an additional section describing the engraving that BF sent to Banks two weeks later by way of Richard Price, reproduced on the facing page. It begins with a general description: “The print contains a view of Champ de Mars and the ball in the air.” Next, the copyist transcribed the legend engraved on the print (quoted in the List of Illustrations), which credited the Robert brothers with the execution of the balloon and ended with the names “Mr. Faujas de Saint Fond & M. Charles.” To this was added a final note explaining that Charles’s name was “wrote with pen, not engraved.” BF must have inserted that name, and with good reason. Charles was not named in many of the articles published in the Jour. de Paris and reprinted elsewhere. The indignant Robert brothers countered with a public letter correcting the articles and “Estampes éparses de tous côtés,” insisting that it was Charles alone who had directed their operations, and that Faujas de Saint-Fond’s role was limited to raising the subscription and issuing tickets: Jour. de Paris, Sept. 14, 1783.

7For background on the Montgolfiers’ hot air balloon see the headnote to BF to Banks, July 27. Etienne’s family, concerned that he was too focused on how his name “vole par toute l’europe,” pressed him to visit customers and talk to BF about marketing paper in America: Jean-Pierre to Etienne Montgolfier, Aug. 30, 1783, described in Gillispie, Montgolfier Brothers, p. 39; see also pp. 34–6.

8Charles had technical assistance from the brothers Anne-Jean and Marie-Noël Robert, instrument makers, who supplied the materials. See the headnote cited in the previous note, as well as Gillispie, Montgolfier Brothers, pp. 27–9; Faujas de Saint-Fond, Description des expériences de la machine aérostatique de MM. de Montgolfier … (Paris, 1783), pp. 7–9.

9BF to Joseph Banks, Oct. 8, 1783 (Royal Society).

1For BF’s attendance at Charles’s lecture in December, 1781, see XXXVI, lxii. After Charles died, the story was told of how BF had attended one of his lectures in company with the Italian physicist Alessandro Volta. BF was so impressed with the experiments that he remarked: “La nature ne lui refuse rien, il semble qu’elle lui obéisse”: Baron Joseph Fourier, “Eloge historique de M. Charles …,” Mémoires de l’Académie des sciences de l’Institut de France (2nd ser., 40 vols., Paris, 1816–78), VIII, lxxiv, lxxvi. WTF knew Charles as well, having attended one of his courses: Chevalier de Saint-Olympe to WTF, Aug. 16, 1783 (APS).

2For the quotation, see the annotation of Banks to BF, Aug. 25. Until this time, the press had reported only on the Montgolfiers’ experiment at Annonay and the fact that Etienne Montgolfier would soon be staging a repetition of it. See, for example, Bachaumont, Mémoires secrets, XXIII, 85, 88–9, 108, 116–18; Jour. historique et politique, no. 33 [mid-August], pp. 359–63; Jour. de Paris, Aug. 27, 1783.

3Jour. de Paris, Aug. 28, 1783; Bachaumont, Mémoires secrets, XXIII, 117–18; Tourneux, Correspondance littéraire, August, 1783, p. 348. The crowd remained transfixed in spite of the rain, which wilted plumes, hats, and dresses: Bachaumont, Mémoires secrets, XXIII, 128–9. See also Gillispie, Montgolfier Brothers, pp. 30–1.

In light of BF’s problems with gout and kidney stones (see the Aug. 27 entry in Baynes’s journal, published above under that date), he probably observed the experiment from his own terrace, which afforded an unobstructed view across the river. That view was reproduced in “Premier Voyage Aërien En présence de Mgr. le Dauphin … Vüe de la Terasse de Mr. Franklin à Passi,” an engraving depicting Montgolfier’s experiment of Nov. 21, 1783.

4Tourneux, Correspondance littéraire, August, 1783, p. 349.

5Bachaumont, Mémoires secrets, XXIII, 171; Jour. de Paris, Sept. 25, 1783.

6The following week, in another article about balloons, the journal referred to the baby who was still awaiting its education, before which, “selon un homme célèbre,” one could not judge whether it would amount to something or nothing: Mercure de France (Jour. politique de Bruxelles), Sept. 27, 1783, p. 178; Oct. 4, 1783, pp. 36–7.

7Ducarne de Blangy, October 3 and 7, 1783 (University of Pa. Library). He cited the Jour. de Genève, Sept. 27, 1783, p. 609. The same quotation, with minor variations, appeared in the Jour. historique et politique, no. 40 [early October, 1783], p. 23.

8This question was discussed at length in the Jour. historique et politique, no. 40 (cited above), and still nagged at La Sablière de la Condamine on March 8, 1784 (APS), when he sent BF a memoir on the subject.

9Métra, Correspondance secrète, XV, 270.

1Bachaumont, Mémoires secrets, XXIV, 65.

2Giacomo Casanova, Ma voisine, la postérité: à Léonard Snetlage … (Paris, 1998), p. 47. The session was described as taking place shortly after d’Alembert died, which was on Oct. 29, 1783. The Jour. de Paris of Nov. 14 reported a public session of the Académie on that day.

3Procès-verbaux des séances de l’académie tenues depuis la fondation de l’Institut jusqu’au mois d’août 1835 (10 vols., Hendaye [Basses-Pyrénées], 1910–22), I, 586.

4Seymour L. Chapin, who traced the many different iterations of BF’s remark, concluded the opposite, citing Le Roy’s close friendship with BF: “A Legendary Bon Mot?: Franklin’s ‘What Is the Good of a Newborn Baby?’” APS Proc., CXXIX (1985), 278–90.

5The fabric had been devised by a M. Bernard: Faujas de Saint-Fond, Description des expériences de la machine aérostatique, pp. 7–9.

6A French “pinte” was roughly equivalent to 47 cubic inches or 0.93 liters: Ronald E. Zupko, French Weights and Measures before the Revolution: a Dictionary of Provincial and Local Units (Bloomington, Ind., 1978).

7To reassure the public, the government issued a statement describing the two experiments that had already been conducted and giving notice that more were being planned with even larger balloons. The “machines” were harmless, being made of fabric and paper, and presumably one day would serve a useful purpose for society: Mercure de France (Jour. politique de Bruxelles) for Sept. 6, 1783, pp. 32–5.

8This exchange took place at the meeting of the Académie des sciences on Aug. 30: Procès-verbaux, CII, 194–5.

9The baron de Beaumanoir lofted a balloon of one and a half feet diameter on Sept. 10, and announced public demonstrations on the next two days: Jour. de Paris, Sept. 11 and 12, 1783. Smaller balloons, eight inches across, were soon being sold by M. Blondy for 6 l.t. apiece: Jour. de Paris, Sept. 14, 1783.

1In L’Air de Lamotte’s hand.

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