Benjamin Franklin Papers

To Benjamin Franklin from William Shervington, 20 June 1753

From William Shervington3

Printed in The Royal Society, Philosophical Transactions, XLVIII, pt. 1 (1753), 318–19.

Antigua, June 20, 1753


Mr. Benjamin Mecom having received half a dozen circulatory letters from you relating to Mercury’s transit over the sun the 6 of last May,4 he put them into my hands. One would have sufficed for our island, as we are not overburthen’d with men, who have a taste that way. Hereunder I send you the result of my observation thereof.*

Sunday, May 6, at 6h 7′ 51″, I observed the western limb of Mercury to touch the western limb of the sun; and, at 6h 10 ′37″, he touch’d the same with his eastern limb, and totally disappear’d. Lat. of the place 17° 0′ N. Lon. by estimation 61° 45′ W. from London.

This was taken by a Graham’s watch,8 and corrected by two altitudes taken by a most exquisite quadrant; viz.

At 6h 58′ 7″, I observed the distance of the sun’s upper limb from the zenith = 72° 21′ 30″. And at 9h 31′ 5″, I observed the same = 36° 17′ 0″.

By the common process (which you may have, if necessary) I found the watch was 0° 4′ 4″ 28‴ too fast; therefore,

From — — — 6 10 37
Take — — — 0 4 4 28
True apparent time of Mercury’s exit here, 6 6 32 32

Pray impart your observation to Your Well-wisher,

William Shervington

[Note numbering follows the Franklin Papers source.]

3William Shervington (c. 1689–1763), clergyman and schoolmaster of Antigua; B.A., Trinity College, Dublin, 1712; his Occasional Poems, printed by BF’s partner Thomas Smith (see above, III, 322n), was probably the first book printed at St. John’s. George D. Burtchaell and Thomas U. Sadleir, eds., Alumni Dublinenses (Dublin, 1935), p. 750; Amer. Antiq. Soc. Proc., XXXVIII (1928), 305, 323; Vere L. Oliver, The History of the Island of Antigua (London, 1894–99), III, 86–7.

4See above, p. 415. BF sent a copy of this letter to Collinson; it was read in the Royal Society, Nov. 15, 1753. He also sent a copy to James Alexander, who in turn gave one to Cadwallader Colden. Colden Paps., IV, 402. BF printed Shervington’s letter in Pa. Gaz., Sept. 6, 1753.

5Possibly the Charles Rose who received an A.M. from Aberdeen, 1721, and an LL.D., 1748, author of a sermon on French Faith and Austrian Gratitude (London, 1759). This may be the same Rev. Charles Rose who received the King’s Bounty for Barbados in 1732 and is reported in Antigua in 1738 and 1748. John P. Anderson, Roll of Alumni in Arts of the University and King’s College, Aberdeen, 1596–1860 (Aberdeen, 1900), p. 60; Oliver, History of Antigua, III, 52–4.

6Richard Tyrell (c. 1716–1766), later rear admiral of the White and commander in chief, Leeward Islands. He was buried at sea, but has a monument in Westminster Abbey. His will mentions books and instruments. Oliver, History of Antigua, III, 118–22.

7John Bird, mathematical instrument maker. See above, III, 484 n.

8George Graham (1673–1751), one of the best mathematical instrument makers in London. He himself observed the transit of 1736. DNB.

9James Short, “Observations of the Transit of Mercury over the Sun, May 6, 1753,” Phil. Trans., XLVIII, pt. 1 (1753), 192–200.

Authorial notes

[The following note(s) appeared in the margins or otherwise outside the text flow in the original source, and have been moved here for purposes of the digital edition.]

º *Dr. Charles Rose,5 who was in Antigua at this time, says, that these observations were taken by Capt. Richard Tyrrel,6 of the said island, and who is possessed of a valuable collection of astronomical instruments, made by Mr. Bird 7in the Strand, London, and that Mr. Shervington only was present.

º †Mr. Shervington has taken the mean of these two altitudes from the error of his watch; and there can be no doubt that his observation is a good one, which, compared with that made in Surry-street by Mr. Short, p. 199, l. i. &c. fixes the longitude of the place of his observation in Antigua 4h 5′ 30″, or 61° 22′ 30″, west of St. Paul’s, London.9

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