The Measure of All Things

by Ken Alder

  “permissible to see”: Talleyrand, AP 12 (9 March, 1790): 104–8. Talleyrand and Miller were in regular communication; see Yves Noël and René Taton, “La réforme des poids et mesures, Origines et premières étapes (1789–91),” in Oeuvres de Lavoisier, vol. 7, Correspondance, Patrice Bret, ed. (Paris: Académie des Sciences, 1997), 6:339–65; John Riggs Miller, Speeches in the House of Commons upon the Equalization of the Weights and Measures of Great Britain (London: Debrett, 1790).

  “the world’s three most enlightened”: BI MS883 fol. 34, Condorcet, “Sur une mesure commune,” n.d. Jefferson worked closely with David Rittenhouse (a mathematician) and Robert Leslie (a watchmaker). For an overview of early American efforts for metric reform, see Julian P. Boyd, “Report on Weights and Measures,” in Thomas Jefferson, The Papers of Thomas Jefferson, Julian P. Boyd, ed. (Princeton: Princeton University Press, 1950–  ), 16:602–17. See also C. Doris Hellman, “Jefferson’s Efforts Toward the Decimalization of United States Weights and Measures,” Isis 16 (1931): 265–314. In 1785 James Madison had also suggested basing a standard of measure on the pendulum; see Madison to James Monroe, 28 April 1785, in The Writings of James Madison, Gaillard Hunt, ed. (New York: Putnam, 1901), 2:142–43. For the early involvement of the U.S. government in metric matters, see Sarah Ann Jones, Weights and Measures in Congress: Historical Summary, National Bureau of Standards, Miscellaneous Publication M122 (Washington, DC: USGPD, 1936).

  “or whatever other latitude”: AP 15 (8 May 1790): 439. This proposal was passed by the king in Proclamation du roi sur le décret de l’Assemblée Nationale du 8 mai 1790, 22 August 1790 (Paris: Imprimerie Royale, 1790). For Miller’s praise, see Miller, Speeches (1790), viii–ix, xiv.

  “with the hope”: Jefferson to Speaker of the House, 4 July 1790, in Jefferson, Papers, 16:653. See his First Report (April 1790), Second Report (20 May 1790), and Final Report (4 July 1790), in Jefferson, Papers, 16:623–48. For Jefferson’s earlier preferences, see Jefferson to Leslie, 27 June 1790, in Jefferson, Papers, 16:576. For the preferences of one Paris savant, see Brisson, “Essai sur l’uniformité de mesures” (14 April 1790), MAS (1790): 722–26.

  “The field that nourishes”: [Laplace], “Discours,” 4 messidor VII [22 June 1799], in Delambre, Base, 3:585. The speech is unsigned, but was delivered by Laplace; see Bigourdan, Système métrique, 160–66.

  “exclude” and “there was nothing”: Borda, “Rapport à l’Académie des Sciences,” 19 March 1791, AP 24 (26 March 1791): 379, 394–97.

  although no two savants could quite agree: On the debates over geodesy, see Jean-Jacques Levallois, Mesurer la terre: 300 ans de géodesie française (Paris: Presses de l’Ecole Nationale des Ponts et Chaussées, 1988); Mary Terrall, The Man Who Flattened the Earth: Maupertuis and the Sciences in the Enlightenment (Chicago: University of Chicago Press, 2002); also see Mary Terrall, “Representing the Earth’s Shape: The Polemics Surrounding Maupertuis’s Expedition to Lapland,” Isis 83 (1992): 218–37; Rob Iliffe, “Aplatiseur du monde et de Cassini,” History of Science 31 (1993): 335–75; John L. Greenberg, The Problem of the Earth’s Shape from Newton to Clairaut: The Rise of Mathematical Science in Eighteenth-Century Paris and the Fall of “Normal” Science (Cambridge: Cambridge University Press, 1995).

  “flattering dream”: Fontenelle, “Physique,” in HAS 1 (1674, pub. 1733), 178. See also d’Alembert, “Pendule,” Encyclopédie, 12:294.

  “the concourse” and “approach perfection”: Condorcet to President of the National Assembly, and Borda, “Rapport,” in AP 24 (26 March 1791): 379, 394–97.

  “divert the attention”: BLL Add MS33272, ff. 97–98, Charles Blagden to Joseph Banks, 8 September 1791, emphasis in original.

  “If other nations adopt”: Jefferson, “Memorandum to James Monroe,” before 4 April 1792, in Jefferson, Papers, 27:818–22. Jefferson received a copy of the French meridian law from Condorcet, translated it himself and wrote back “to confess that it is not what I would have approved”; see Condorcet to Jefferson, 3 May 1791, Jefferson to Short, 28 July 1791, Jefferson to Condorcet, 30 August 1791, in Jefferson, Papers, 20:353–60; 20:686–91; 22:98–99.

  the budget for the creation: Borda’s new budget came to 300,000 livres; see AN F12 1289, [Académie des Sciences], 19 March 1791. The decree of 20 August 1790 had set the Academy’s total budget at 93,458 livres; see PVCIP, 1:260n. For contracts with instrument-makers, see AN F12 1289, Borda to Pavé (Min. Int.), 12 brumaire II [2 November 1793]. For a description of Lenoir—he was 4 foot 10 inches tall—see CNAM R6, “Etienne Lenoir, Certificat de résidence,” 22 floréal II [11 May 1794]. On the personnel in Lenoir’s shop, see AAS Lavoisier 1967, Lavoisier, “Etat des ouvriers et coopérateurs,” [1793].

  “preserved their pensions”: Mercier, Le nouveau Paris, 3:44.

  “those cowardly lackeys” and”a little gâteau”: Jean-Paul Marat, Les charlatans modernes; ou, Lettres sur le charlatanisme académique ([Paris]: n.p., 1791), 40.

  Delambre himself later speculated: On Borda’s motives, see Delambre, Grandeur, 202–3, 213; also Lalande, Bibliographie astronomique, 718. On Laplace’s motives, see Laplace, “Mathématiques,” Ecoles Normales, 5:203–14.

  “Everything in nature”: BN Vz 1695, [Pierre Hourcastrenne], Dissertation sur les causes qui ont produit (Paris: Pougin, [1791]), 18–19. For speculation about change in the shape of the earth over time, see Laplace, “Mathématiques,” Ecoles Normales, 5:212. For other objections to the meridian, see AN A34 1037, “Observations sur le rapport relatif au choix d’une unité de mesure,” n.d.; AN AFII 67 plaq. 496, Gueroult, Observations sur le nouveau système des poids et mesures (Paris: Rousyef, II [1794]).

  All along, Lalande: For Lalande’s objections, see AP 11 (6 February 1790): 486–87.

  “Is it possible”: Delambre, 14 April 1793, in Bigourdan, Système métrique, 128–30.

  The council voted: For Delambre’s passport, see ADSe 3AZ259, Destournelles and Coulenbeau, “Extrait de registres des déliberations du Conseil Général,” 15 April 1793. The passport itself was granted on April 24; see BMA Arch Rev 2K10, Delambre, “Pétition,” 9 August 1793. See Delambre’s account in Delambre, Base, 1:41–42. For one of Delambre’s cautionary letters, see BMA 1953(17), Delambre to [?], 31 March [1793].

  When he passed through: For Delambre’s dossier, see BMA Arch Rev 2K10, Delambre, “Pétition,” 9 August 1793.

  “and we counted”: AOP E2-6, Delambre, “Registre,” 127. See also AOP MS1033c, Garcia to Delambre, 7 June 1793.

  In Watten, a small town: For Delambre’s progress from Watten to Bayonvilles, see AOP E2-6, Delambre, “Registre,” 132–98; AAS Cabrol 120/121, Delambre to Lavoisier, 11, 16 July 1793; Delambre, Base, 1:44.

  “I admire you”: CUS, Delambre to Amélie Lefrançais, 22 August 1793.

  As for Lefrançais: For Lalande’s hopes for his nephew’s election, see CUS, Lalande to Delambre, 28 July [1793].

  “I don’t know” and “The suppression”: AAS Lavoisier 1128(41), Lavoisier to Delambre, [August 1793]. See the advance warning of the Academy’s demise, which Lavoisier provided to Delambre, in AAS Bertrand Col. 4, Lavoisier to Delambre, 23 July 1793.

  “There is no more”: BNRC Ge DD 2066 (3), Cassini IV, “Mémoires, 2ème dialogue,” 31. For attempts to save the Academy, see PVCIP, 2:240–60. For the Academy in general, see Roger Hahn, The Anatomy of a Scientific Institution: The Paris Academy of Sciences, 1666–1803 (Berkeley: University of California Press, 1971).

  Hence, the law established: The demand for a “provisional” meter had been first made by Roland; see AP 41 (3 April 1792): 100. First presented to the CIP by Arbogast, “Rapport,” July 1793, in PVCIP, 2:9–20. Based on a report by Borda, Lagrange, and Monge to the Academy of Sciences and sent to the committee on 29 May 1793. For the legislation, see AP 70 (1 August 1793): 70–74, 112–18. BN Le38 2501, Arbogast, Sur l’uniformité et le système général des poids et mesures (Paris: Imprimerie National, 1793).

  Borda had privately estimated: Fo
r Borda’s estimate, see AAS Chabrol 1/71, Borda to Condorcet, [May 1792].

  The plan for a new: For the metric needs of the cadastre, see Jean-Baptiste Jollivet, Rapport et projet de décret sur une nouvelle et complète organisation de la contribution foncière, 21 August 1792 (Paris: Imprimerie Nationale, 1792), 151–81. For the calculation of the provisional meter, see AAS, “Procès-verbaux de l’Académie” 110 (19 January 1793): 327–35; published as Borda, Lagrange, and Laplace, “Fait à l’Académie des Sciences, sur l’unité des poids et mesures et sur la nomenclature de ses divisions,” in CUL QC89.F8A16, Recueil de pièces relatives à l’uniformité des poids et mesures (Paris: n.p., 1793).

  “The new measures are being adopted”: CUS, Lalande to Delambre, 2 frimaire II [23 November 1793].

  his hometown of Amiens: For Amiens, see AAS Dossier Delambre, Delambre to Lavoisier, 18 August 1793; AOP MS1033c, Delambre, “Méridien de France (Partie du Nord),” [1793–94].

  “To be reasonable”: [Delambre], “Proposition d’un citoyen,” Affiches du Département de la Somme 28 (9 July 1791): 120–21. For Delambre’s participation in the Société, see BMA Arch. Rév. 3I5(1), “Société des Amis de la Constitution,” 16 April 1791. Delambre did not visit Amiens once between 1782 and 1790; see Bigourdan, Astronomie d’observation, 169.

  “a man without passion”: [François-Noël Babeuf], Affiches du Département de la Somme 29 (16 July 1791), 125; 30 (23 July 1791): 128, in M.-J. Foucart, “Un aspect inconnu de Babeuf à l’été charnière de 1791,” Société des Antiquaires de Picardie 62 (1989): 371–79.

  Delambre paid him: For salaries on mission, see AAS Dossier Delambre, Delambre to Lavoisier, 18 August 1793. Delambre, “Mesure du méridien, dépense faite par Delambre,” 26 floréal III [15 May 1795], in Observatoire de Paris, Longueur et temps (Paris: Observatoire de Paris, 1984); Delambre, Grandeur, 281.

  “They reported seeing”: Delambre to Lavoisier, 13 frimaire II [3 December 1793], in Bigourdan, Système métrique, 132.

  “odious sign of extinct despotism”: Jacques Soyer, “Un acte de vandalisme dans le département du Loiret en l’an II,” Bulletin de la Société Archéologique et Historique de l’Orléanais 18 (1917): 99–106.

  at Châtillon: See AOP E2-6, Delambre, “Registre,” 270.

  “should the meridian”: Lagrange [CPM] to Delambre, 8 nivôse II [28 December 1793], in Bouchard, Prieur, 461. See also Lagrange to Comité de Salut Public, 8 nivôse II [28 December 1793]; Carnot and Lindet, 9 nivôse II [29 December 1793], in Bouchard, Prieur, 461–62.

  He wrote to the commission: For Delambre’s request for a delay, see ENPC MS724, Delambre to [Lagrange, CPM], 13 nivôse II [2 January 1794]. Delambre, Base, 1:48.

  Their sealed response: Delambre noted in the margin that the commissioner was Prony in KM, Delambre, Base, 1:48. See also Bigourdan, Système métrique, 133; ENPC MS724, CPM to Commission de Subsistances, 15 nivôse II [4 January 1794].

  “Hey, you bastards!”: Denis Lottin, Recherches historiques sur Orléans (Orléans: Jacob, 1838), 4:195, 427–28.

  some twenty-four hundred miles: For Delambre’s estimate of 1,200 lieues (2,400 miles), see Delambre, “Mesure du méridien, dépense faite par Delambre,” 26 floréal III [15 May 1795], in Observatoire de Paris, Longueur et temps; see also ENPC MS726, Delambre, “Mesure du méridien,” 19 messidor II [7 July 1794].

  “It began to rain”: AOP E2-6, Delambre, “Registre,” 3 pluviôse II [22 January 1794].

  “Citizen, The Commission”: Delambre, Base, 1:49. See also ENPC MS724, Min. Int. to Prony, 18 nivôse II [7 January 1794].

  “The Committee of Public Safety”: AN AF II 67 plaq. 496, Prieur, Barère, Carnot, Lindet, and Billaud-Varenne, “Le Comité de Salut Public, considérant combien . . . ,” 3 nivôse II [23 December 1793]. For the published version, see RACSP, 9:600. Note that in Delambre, Base, 1:50, Delambre gives the names of the signatories as the three (dead) radicals Robespierre, Couthon, and Collot-d’Herbois, rather than the three (living) engineers-moderates who actually signed the order: Prieur, Carnot, and Lindet. However, he corrects this deliberate change in a marginal note in KM, Delambre, Base, 1:50.

  “Even though, for the life of me”: AOP E2-19, Delambre to CPM, 4 pluviôse II [23 January 1794].

  his patron was likewise hauled off: For d’Assy’s arrest, see AN F7 4722, Comité de Sûreté Générale, “Geoffroy d’Assy,” 6 pluviôse II [25 January 1794].

  FOUR: THE CASTLE OF MONT-JOUY

  “There is almost nothing”: Blaise Pascal, Pensées sur la religion, Louis Lafuma, ed. (Paris: Luxembourg, 1951), 52–53 (fragment 60–108).

  “Time has done more”: AOP E2-19, Méchain to Lalande, 19 ventôse III [9 March 1796]. News of Méchain is found in CUS, Lalande to [Delambre], 28 July 1793. For the effect of heat on the circle, see AOAB Cart. 88, Méchain to Oriani, 2 April 1795.

  “in order to avoid”: Jaume Carrera i Pujal, La Barcelona del segle XVIII (Barcelona: Casa Editorial, 1951), v. 1; Maldà, Calaix de Sastre, 2:91–93; Torreilles, Perpignan, 2:62–63.

  he was entitled to a salary: On Méchain’s pay, see AAS Lavoisier 1228(36), Lavoisier to Méchain, 6 October 1793. For Méchain’s deference to the defunct Academy, see AOP E2-19, Méchain to Borda, 10 January 1794. For Méchain’s fears of replacement, see AOP E2-19, Méchain to Borda, 10 January 1794. For Delambre’s speculation as to why he was purged while Méchain was spared, see Delambre, Grandeur, 214.

  So when he was offered: For rumors in Paris that Méchain had received outside (foreign) offers of employment, see KM, Delambre, Base, 1:52. For the correspondence regarding Méchain’s funds, see CUL MS4712++, Lavoisier, “Registres de l’Académie des Sciences,” 1792–93.

  Delambre had offered: For Delambre’s offer to help, see ENPC MS724, Delambre, “Mesure du méridien,” 19 messidor II [7 July 1794].

  “conduct surveillance”: ADPO L1128, Gauderique Costaseca et al., “Extrait des registres de la municipalité de Valmagnne [sic],” 7 October 1793.

  Francesc-Xavier Llucía: For the help of Llucía, see ADPO L1128, Méchain to Lucia [sic], 6 October 1793.

  “infinitely precious”: Lalande, Pingré, Chabert, Cassini IV, and Méchain, “Rapport,” 4 June 1791, in Antoine Albitreccia, Le plan terrier de la Corse au XVIIIe siècle (Paris: Presses Universitaires de France, 1942), 74.

  “I could rely on him”: Méchain as quoted in Delambre, Base, 1:430. Delambre notes that the data for this site were recorded in Tranchot’s hand; see KM, Delambre, Base, 1:429–35. He also notes that Méchain supplied Tranchot with correction factors without explaining how or why to use them; see Delambre, Grandeur, 280.

  Tranchot was obliged to supply: For Tranchot’s supply of the latitude data for the Spanish forts to the French army, see Henri-Marie-Auguste Berthaut, Les ingénieurs géographes militaires, 1624–1831: Etude historique (Paris: Imprimerie du Service Géographique, 1902), 1:172. I have not been able to locate the original sources for this claim. Unfortunately, Berthaut almost never cites his sources, and there is something contradictory about the story as he tells it. He says Tranchot got these plans to Dugommier in the year IV, but Dugommier died in the year II; and the plans would not have been any use in the year IV, since the French had already occupied most of these forts and the peace had been signed in the year III. Despite this slip, however, Berthaut was an extremely reliable and knowledgeable historian, who worked exclusively with archival materials from the Dépôt de la Guerre, to which he had complete access for many years. Many of the documents in that holding have since been misplaced. So the gist of his account is likely to be correct, though the timing and manner of the espionage are unclear.

  Méchain and Commander Bueno: For Méchain at Puig Camellas, see Méchain, in Delambre, Base, 1:429–45.

  Lalande, for one: For Lalande’s news of Méchain and Tranchot, see CUS, Lalande to Delambre, 3 frimaire II [23 November 1793].

  “It is for the sake”: ADPO L1128, Tranchot (at Puig de l’Estella) to [Llucía], 3 November 1793. Trancho
t is quoting from Méchain’s letter to him, now lost.

  “force of arms”: ADPO L1128, Tranchot to [Llucía], 3 November 1793.

  “It is time”: Llucía, in Vidal, Pyrénées-Orientales, 3:46.

  Nor would Méchain be allowed: For the prohibition against sending data, see AOP E2-19, Méchain to Borda, 10 January 1794. For the orders of Ricardos, see Delambre, Notice historique sur M. Méchain, 18.

  Jacques-Coquille Dugommier: On Dugommier, see Arthur Chuquet, Dugommier, 1738–1794 (Paris: Fontemoing, 1904). On the battles of 1793–94, see Joseph-Napoléon Fervel, Campagnes de la Révolution française dans les Pyrénées-Orientales (Paris: Dumaine, 1861), 2:210–11.

  “But alas, where am I?”: AOP E2-19, Méchain to Borda, 10 January 1794. There are two copies of the letter from Méchain to Borda of 10 January 1794; neither is complete and each contains elements that the other omits: (1) AOP E2-19, Méchain to Borda, 10 January 1794; and (2) ENPC MS1504, Méchain to Borda, 10 January 1794.

  Certainly he wished to prove: For the Barcelona measurements, see Méchain’s later admission that he was crippled in his right arm and had to operate “with the help of others” in AOP E2-19, Méchain to Lalande, 4 messidor IV [22 June 1796].

  Méchain climbed the hill: For the Mont-Jouy triangulations, see Delambre, Base, 1:503. For the weather on March 16, see Diario de Barcelona 77 (18 March 1794): 305.