To Charles Morton4
Copy: The Royal Society
This letter was read at a meeting of the Council of the Royal Society, Nov. 14, 1765. At the previous meeting the Council had directed Morton to find out from Franklin the best way to communicate with the astronomers and geodetic surveyors, Charles Mason (1728–1786) and Jeremiah Dixon (1733–1779), then in America, and to send them needed instruments. They had been engaged since 1763 in running the famous boundary line between Pennsylvania and Maryland, and the Royal Society had approved their proposal to measure a degree of longitude and a degree of latitude in Maryland and Pennsylvania. Nevil Maskelyne, the astronomer royal (above, XI, 482 n), to whom Mason and Dixon had originally submitted the proposal, sent them instructions in November 1765 and in December he sent them a clock owned by the Royal Society which he himself had used some years earlier in astronomical observations at St. Helena and Barbados. The clock helped Mason and Dixon in their work considerably.5
October 29, 1765
November 14 1765
|At a Council of the Royal Society —|
|1||The President||7||Dr. Heberden|
|2||Mr. Burrow||8||Mr. Raper|
|3||Dr. Chandler||9||Dr. Birch||Secs.|
|4||Mr. Mauduit||10||Dr. Morton|
|6||Lord Chas. Cavendish|
The minutes of the last Council were read.
Dr. Morton reported that he had executed the business he was charged with at the last Council, viz, that he had sent to Mrs. Mason and Dixon, two Copies of the resolutions relating to them, which would be forwarded by the New York Pacquet, on the second Saturday in Nov.
The three following letters to him were also read, viz, from Dr. Franklin F.R.S. from the right Honble Lord-Baltimore, and from Mr. Penn.
October 29 1765
The Pacquet is the safest Conveyance, but does not sail ’till the second Saturday in November. If you send your Letter, with a Duplicate of it to me; I will take Care to forward them by different Ships, The first that leave England for North America. If the letters are directed to Messrs. Mason and Dixon at Philadelphia; It will be sufficient. I will put them under Cover to a friend, who will see them carefully delivered. The Post master General can do no more. The Rods and Thermometers should go in a Ship to Philadelphia; I will enquire, and inform you when one is expected to sail for that Port.6 The pacquet goes from Falmouth to New york, and therefore cannot so conveniently take those things as there would be Land carriage, first from London to Falmouth, and then in America, from New york to Philadelphia.
I am with great Esteem Dear Sir Your most obedient humble Servant
4. For Morton, secretary of the Royal Society, 1760–74, and later principal librarian of the British Museum, see above, X, 71 n.
5. On Mason and Dixon and their work in America, see Thomas D. Cope, “Collecting Source Material about Charles Mason and Jeremiah Dixon,” APS Proc., XCII (1948), 111–14; “A Clock Sent Thither by the Royal Society,” ibid., XCIV (1950), 260–71; “Some Contacts of Benjamin Franklin with Mason and Dixon and their Work., ibid., XCV (1951), 232–8; H.W Robinson, “A Note on Charles Mason’s Ancestry and His Family,” ibid., XCIII (1949), 134–6.
6. The bill of lading for seven cases shipped to Mason and Dixon aboard the ship Ellis by Maskelyne is reproduced in facsimile in APS Proc., XCIV (1950), 266. The ship was wrecked off the New Jersey coast, March 1, 1766, but the surveyors received the clock and other instruments slightly damaged but still usable. Pa. Gaz., March 13, 1766, and references previously cited.