The Difference in Time of the Meridians of Diverse Places Computed from Observations of the Eclipses of Jupiter's Satellites, by the Reverend Mr. Derham Canon of Windsor, and F. R. S.

V. The Difference in Time of the Meridians of diverse Places computed from Observations of the Eclipses of Jupiter's Satellites, by the Reverend Mr. Derham Canon of Windsor, and F. R. S. Sir Thomas Derham, at Florence, having lately favoured me with his Transcript of Monsignor Bianchini's Observations of the Eclipses of Jupiter's Satellites, from the Year 1721, I have laid them down so as to be seen at an easy View, for the Service of the R. S. Monsieur Bianchini faith, they were made with a Telescope of Campani's grinding of 23 Roman Palms: That Father Jo. Bapt. Carboni at Lisbon made use of such another of the same Make, Length, and Goodness; and therefore thinks the Times assigned by them, to be exact; that he drew Meridian-Lines at Assisi in Ombria & Urbino; at St. Quirico in Tuscany and Florence: And that Monsignor Euftach. Manfredi at the Observatory of Bologna, and he observed the Immersion of the first Satellite on 25 August within two Seconds of one another; Manfredi with a Glass of 8 Bononia Feet, and he with one of 11; both made by Campani. With his own, Bianchini hath inserted some Observations, made at the same time by Father Carboni at Lisbon, and Father Grammatici at Ingolstadt; Monsieur Maraldi at Paris, and Monsignior Euftachius Manfredi at Bologna; as also an Immersion observed by Mr. Molyneux near London (I suppose at Kew) with his reflecting Telescope, and two at Pekin in China by Father Ignatius Kogler a Jesuit: But I suppose there is a Mistake in the Observation of November 30, 1724, that it was an Emer- sion, not an Immersion; the Immersions of the first Satellite being not to be seen then. Sir Thomas tells me that Signior Bianchini promiseth his Observations of the circumjovial Eclipses from the Year 1700, and that he will send the Society in November his new Globe of Venus. As to the Bologna Observations, they were put into my Hands by Dr. Rutty, Secr. to the R.S.; and are said to be made with a Glass of Campani's, of 11 Bologna Feet. And to save the Peruser the Trouble, I have computed the Difference in Time between the Places in Bianchini's and Manfredi's Catalogues, and some Observations that I had of mine own. | Rome and Lisbon | Rome and Kew | Ingolstad and Lisbon | St. Quirico and Upminster | |-----------------|--------------|----------------------|--------------------------| | H. | H. | H. | H. | | 24 46 | 45 47 | 22 53 | 47 50 | | 25 34 | | 23 21 | | | 26 34 | | | | | 29 | 49 10 | | | | 26 44 | | | | | 26 54 | | | | | 28 11 | | | | | Rome and Paris | Rome and Southwick in Northamptonshire | Urbino and Lisbon | Paris and Lisbon | |----------------|---------------------------------------|-------------------|-----------------| | 39 48 | | | | | 40 50 | | | | | 36 16 | | | | | 38 56 | | | | | 40 17 | | | | | Rome and Ingolstad | Paris and Bologne | |--------------------|-------------------| | 2 51 | | | 4 1 | | | St. Quirico and Lisbon | Bologne and Lisbon | |------------------------|--------------------| | 22 30 | 21 28 | | 37 40 | 3 43 | Ob- Observations of the Eclipses of Jupiter's Satellites made by Monsignor Bianchini at Rome, and other Places: With Accounts of such as he received from other Places. | Days of the Month | Time of Observation | Satel. | Place where observed | |------------------|--------------------|--------|---------------------| | Anno Domini 1721 | | | | | Apr. | 3 | H. | | | | 15 4 32 | Im. | At Rome. | | Jun. | 21 | 8 46 | Em. | | | | | Rome. | | Anno Domini 1722 | | | | | Jun. | 9 | 13 20 | E. | | | | | Rome. | | | 18 | 9 36 | E. | | | | | At Albano. | | Jul. | 11 | 9 49 | E. | | | | | Rome. | | | 27 | 8 7 | E. | | | | | Rome. | | Aug. | 19 | 8 26 | E. | | | | | Rome. | | Anno Domini 1723 | | | | | Mar. | 26 | 17 14 | I. | | | | | Rome. | | Apr. | 11 | 15 31 | I. | | | | | Rome. | | May | 3 | 15 48 | I. | | | | | Rome. | | | | 15 43 | I. | | | | | At Ingolstadt by F. Grammattici. | | | 27 | 18 56 | I. | | | | | Rome. | | Jun. | 5 | 12 16 | I. | | | | | Rome. | | | 12 | 14 11 | I. | | | | | Rome. | | Jul. | 23 | 9 11 | E. | | | | | Lisbon, by Fa. Carboni. | | | 30 | 11 7 | E. | | | | | Rome. | | Aug. | 8 | 7 32 | E. | | | | | At Ocricoli in via flaminia. | | Sep. | 15 | 9 35 | E. | | | | | At Assisi in Umbria. | | | 7 | 9 50 | E. | | | | | Urbino. | | | | 8 21 | E. | | | | | Lisbon. | | | 23 | 8 17 | E. | | | | | At Muceria in Umbria. | | Oct. | 16 | 8 36 | E. | | | | | At Albano in the via appia. | | Days of the Month | Time of Observation | Satel. | Place where observed | |------------------|--------------------|--------|---------------------| | Anno Domini 1724 | | | | | Jun. | 8 | 14 3 | Carboni at Lisbon. | | | | 15 56 | I. | | | | 23 | 13 42 50 | | | | 30 | 15 34 29 | | | | 14 | 8 55 | | Aug. | 10 | 10 45 | E. | | | | | Rome, but doubtful. | | | 17 | 12 49 | E. | | | | | Rome. | | | 26 | 9 6 | E. | | | | | Rome. | | Sep. | 11 | 7 30 | E. | | | | | Rome. | | | 18 | 9 28 | E. | | | | | Rome. | | Oct. | 11 | 9 53 | E. | | | | | Albano. | | | 14 | 9 31 | E. | | | | | From the Limb of 4 into 4 Shadow Albano. | | Nov. | 12 | 8 16 | E. | | | | | Rome. | | | 19 | 5 33 | E. | | | | | Rome. | | | 30 | 6 14 | I. | | | | | At Pekin in China, by F. Kogler the Jesuit. | | Dec. | 5 | 6 42 | E. | | | | | Rome. | | Anno Domini 1725 | | | | | Jun. | 19 | 15 17 | I. | | | | | Rome. | | July | 5 | 13 32 | I. | | | | | Albano. | | | 7 | 14 55 | I. | | | | | Pekin. | | | 21 | 11 45 | I. | | | | | Rome. | | | 28 | 13 39 | I. | | | | | Mr. Molineux near London. | | | 12 | 12 26 | I. | | | | | Lisbon. | | Day of the Month | Time of Observation | Satel. | Place where observed | |------------------|---------------------|--------|----------------------| | Nov. 15 | 9 53 50 | E. | Rome | | Nov. 24 | 8 24 50 | E. | Lisbon | | Dec. 17 | 6 15 15 | E. | Rome | | Dec. 17 | 6 20 30 | E. | Rome | Anno Domini 1726 Jul. 17 | 13 28 46 | I. | Rome | | | 13 24 45 | I. | Ingolstad | | | 12 1 52 | I. | Lisbon | | Aug. 2 | 11 40 0 | I. | St. Quirico in Tuscany | | | 11 41 20 | I. | Ingolstad | | | 13 36 0 | I. | Siena in Tuscany | | | 12 13 30 | I. | Lisbon | | | 15 28 29 | I. | Florence | | | 14 8 46 | I. | Lisbon | | | 15 29 0 | I. | Bologne | | | 11 54 24 | I. | Bian. | | Aug. 25 | 11 56 18 | I. | At Man. | | | 10 32 57 | I. | Bol. | | Sep. 26 | 8 41 0 | I. | Ingolstad | | | 8 39 20 | I. | Paris | | Oct. 1 | 16 7 45 | I. | St. Quirico | | Nov. 20 | 7 46 30 | E. | Rome | | | 6 20 19 | E. | Lisbon | | Dec. 6 | 5 58 0 | E. | Bologne | | | 5 24 0 | E. | Paris | Anno Domini 1727 Mar. 8 | 6 42 50 | E. | Rome | | Aug. 5 | 15 18 27 | I. | Rome | | | 15 0 8 | I. | Rome | | | 14 21 12 | I. | Paris | | | 12 0 0 | I. | Rome | | Sep. 6 | 11 55 15 | I. | Bologne | | | 11 19 43 | I. | Paris | | Oct. 15 | 10 41 30 | I. | Albano | | | 6 5 54 | I. | Albano | | | 12 33 23 | I. | Albano | Anno Domini 1728 Jan. 15 | 13 13 46 | E. | Rome | | Feb. 16 | 9 46 56 | E. | Rome | | Mar. 26 | 8 32 7 | E. | Rome | Observations made at the Observatory of Bologna, by Monsignor Eustachius-Manfredi. Anno Domini 1726 Aug. 16 | 15 29 0 | I. | Dubious | | | 11 54 24 | I. | Dubious | | Nov. 27 | 9 35 11 | E. | Dubious | | Dec. 4 | 11 27 45 | E. | Dubious | | | 5 47 4 | I. | Dubious | | | 7 56 23 | E. | The third began to emerge. | | | 29 59 26 | E. | Just begun | Anno Domini 1727 Jan. 2 | 9 45 27 | I. | Dubious | | | 11 53 38 | E. | Dubious | | | 7 51 54 | E. | Dubious | | | 8 54 12 | E. | Dubious | | Feb. 7 | 5 50 5 | I. | Dubious | | | 7 52 54 | E. | Dubious | | | 8 37 59 | E. | Air thick | | Aug. 21 | 13 34 39 | I. | Dubious | | Sep. 6 | 11 55 17 | I. | Dubious | | | 10 48 59 | I. | Dubious | | | 12 40 30 | E. | Dubious | | Oct. 13 | 16 5 45 | I. | Dubious | | | 12 29 42 | I. | Dubious | | | 8 55 34 | E. | Dubious | | Nov. 30 | 11 1 9 | I. | Dubious | | | 9 5 15 | I. | Dubious | | | 8 44 13 | E. | Dubious | VI. Extract