Roemer's Speed of Light

Cohen I. B. , “Roemer and the first determination of the velocity of light (1676)”, Isis, xxxi (1940), 327–79, pp. 345–6. For the argument that Roemer, not Cassini, was the first to suggest this interpretation, see Pedersen K. M. , “La Vie et l'oeuvre de Roemer”, in Roemer et la vitesse de la lumière, ed. by Taton R. (Paris, 1978), 113–28, pp. 119–20.

“Demonstration tovchant le mouvement de la lumière trouvé par M. Römer de l'Académie royale des Sciences”, Journal des Sçavans , 7 December 1676, 233–6 (reprinted in Cohen, op. cit., 373–6, and Taton , op. cit., 151–4). “A Demonstration concerning the Motion of Light, communicated from Paris, in the Journal des Sçavans, and here made English”, Philosophical transactions, xii (1677), 893–4 (reprinted in Cohen, op. cit., 377–8).

Cohen , op. cit., 347–9.

Gillispie C. C. (ed.), Dictionary of scientific biography, xi (New York, 1975), 525–7, p. 526.

Débarbat S. , “La Qualité des données d'observations traitées par Roemer”, in Taton , Roemer et la vitesse de la lumiére, 143–51, p. 150.

Cassini G. D. , Les Elemens de l'astronomie verifiez par Monsieur Cassini par le rapport de ses tables aux observations de M. Richer faites en l'Isle de Cayenne (Paris, 1684). Reprinted in Mémoires de l'Académie royale des Sciences, depuis 1666 jusqu'à 1699, 9 vols numbered iii-xi (Paris, 1729–33), viii, 53–117, pp. 113–17.

Flamsteed J. , “Johannis Flamstedii Derbiensis Angli, ad Clarissimum Cassinum Epistola”, Philosophical transactions, viii, no. 96 (21 July 1673), 6094–6[1]00, pp. 6099–6[1]00.

Cassini to Flamsteed , 1 August 1673, The correspondence of Henry Oldenburg, ed. by Hall A. R. and Hall M. B. (Madison and London, 1963–), x, 107–9.

Roemer , “Demonstration”, 233–5.

Horrocks arrived at 14″ in his Venus in Sole visa (see The transit of Venus across the Sun , tr. by Whatton A. B. (London, 1859), 202–16). In the various manuscript pieces later assembled by John Wallis under the title Astronomia Kepleriana defensa & promota Horrocks used 15″ and 14″, see Opera posthuma (London, 1673), 160, 164. Wendelin arrived at solar distances of 13,740 and 14,656 Earth radii, corresponding to solar parallaxes of 15″ and 14″, see Riccioli G. B. , Almagestum novum (Bologna, 1651), i, 109. Streete followed Horrocks and chose 15″ as his solar parallax, see Astronomia Carolina (London, 1661), 12.

Picard , Mesure de la Terre (Paris, 1671). Reprinted in Mémoires (see ref. 6), vii, part 1, 131–90, p. 176.

Ibid.