Prior to the Revolution charting of the American coast was dominated by British hydrographers, whose work was most famously recorded in the English Pilot. Fourth Book and later The Atlantic Neptune. These charts were highly regarded, and hydrographic surveys were complex, manpower intensive and prohibitively expensive.

Due to these “barriers to entry,” many American charts produced in the post-war years were largely copied from their British predecessors, often in a simplified form. The most noteworthy instance of this pattern is Mathew Clark’s Complete Set of Charts of the Coast of America (see item 11). Americans did however publish some truly original charts, a few examples of which are displayed here.

11. Published & Sold by Matthew Clark (1714-1798), CHART OF THE COAST OF AMERICA Thro’ the GULPH of FLORIDA / CHART OF THE COAST OF AMERICA Through the GULPH OF FLORIDA To the Entrance of the GULPH OF MEXICO. Boston, [1789]. Image courtesy of the Harvard Map Collection.

Clark’s ambitious Complete Set of Charts of the Coast of America was the first atlas of any kind published in the United States. It comprised 18 charts, together providing coverage from Cape Breton to southern Florida. All were derivative from British prototypes, a point which Clark actually used as a selling point, asserting that they were “to be accurately protracted from the latest surveys of Holland and De Barr.” Displayed here are the joined charts for Florida and the Gulf of Mexico, based not on Des Barres’ Atlantic Neptune but on a chart that had appeared in Sayer & Bennett’s 1775 American Atlas.

Though he is not acknowledged, recent research has shown that “Clark’s” charts were compiled—and in some cases engraved—by one Bartholomew Burges. Clark stepped in as publisher when Burges ran into financial difficulties, but the relationship ended in a vitriolic dispute that played out in the Boston and New York press.

11a. Osgood Carleton, “ADVERTISEMENT.”[Boston, 1789.] Image courtesy of the Harvard Map Collection.

This “Advertisement” (i.e., endorsement) by Carleton was printed on the verso of the title page to Clark’s atlas. As an unknown in the Boston mapmaking community, Clark would have valued the recommendation of a respected figure such as Carleton. Though there is no evidence that Clark did anything other than adapt existing British material for his charts, Carleton asserts that they are “more accurate than any before published”

12. Capt. Paul Pinkham / John Norman, A CHART of NANTUCKET SHOALS SURVEYED by Capt. Paul Pinkham. Boston, Feb. 10th, 1791. Image courtesy of the Harvard Map Collection.

Norman was the most notable of Boston’s post-war map engravers and publishers, if not for the quality of his work then for his involvement with some of the most important maps and charts of the day. After engraving some of the charts for Clark’s atlas he began to issue his own charts of American waters and in 1791 advertised the American Pilot. Unlike Clark’s work the Pilot included original material, notably this chart of the waters around Martha’s Vineyard and Nantucket.

This chart was a great improvement over Clark’s depiction of the area, being at a larger scale and providing far more detail. It was particularly valuable for its treatment of the dangerous shoals east of Nantucket, using information obtained by surveys made from atop Nantucket Light by Peleg Coffin and lighthouse keeper Paul Pinkham.

13. [Jonathan] Price & [John] Strother, … an actual SURVEY of the Sea COAST and inland Navigation from CAPE HENRY to CAPE ROMAN … New Bern, North Carolina, 1798. Image courtesy of the Library of Congress.

Price and Strother are today better known for their map of North Carolina (see item 7 in the “States” section of this exhibit). Yet their state survey had an important hydrographic component, and Price had promised early on to survey “soundings on the sea coast[,] dangerous shoals on Cape Fear, Cape Lookout and Cap Hatteras, all sand banks, inlets and the depth of water therein, soundings and shoals in Pamlico and Albermarle Sound…” The need for such a survey was clear: The waters around the Outer Banks are shifting and treacherous, and existing charts were too small in scale, outdated, or difficult to obtain.

This chart predated the publication of the state map by several years, and it may have been hurried into print to satisfy the wishes of Price and Strother’s patron John Gray Blount. Note the large compass rose at lower right center; it points directly to Ocracoke Inlet, where Blount had built a large mercantile establishment.

14. [Jonathan] Price & [John] Strother, A MAP of Cape Fear River and Its Vicinity from the Frying Pan Shoals to Wilmington by actual Survey … Philadelphia, [ca. 1800]. Image courtesy of the Harvard Map Collection.

The Price-Strother charts are excellent, providing more detail of coastal features and soundings than found on their predecessors, particularly around critical areas such as shoals and inlets. This large-scale chart of Cape Fear would have been particularly valuable, for the development of Wilmington had been hindered by the difficulty of navigating the lower reaches of the Cape Fear River and the surrounding shoals.

15. John Churchman, … THIS MAGNETIC ATLAS or VARIATION CHART … Philadelphia, 1790. Image courtesy of the Harvard Map Collection.

American contributions to navigation were theoretical as well as practical. Ben Franklin, for example, was one of the first to posit the existence of the Gulf Stream. Another such was the attempt of Pennsylvania surveyor John Churchman to solve the problem of determining longitude at sea, which had exercised navigators, scientists, inventors and cranks for centuries (By 1790 the superb chronometers of Englishman John Harrison had yielded a practical solution, but they remained expensive and hard to obtain.)

Churchman claimed that his Magnetic Atlas or Variation Chart would enable navigators to determine their longitude using only their knowledge of their latitude and the local magnetic variation of the compass from true North. Unfortunately for him his proposal was both theoretically incorrect and practically impossible. It was scornfully rejected by the American Philosophical Society and largely ignored by the Board of Longitude in London.