Mapping New York City's Waterways

This week’s map is a colorful nautical chart, where the numbers in the water indicate soundings (measurements of the depth of the water) in fathoms (one fathom equals six feet). The map is oriented with north to the right and shows the western end of Long Island, including four of Brooklyn’s original six towns. Can you spot them?

A draught of New York from the Hook to New York Town was originally created around 1730 by British navigator and cartographer Mark Tiddeman. Despite inaccuracies that could put ships at risk, it was published throughout the 18th century in The English Pilot, Fourth Book—an ambitious marine atlas begun in 1671 by a prominent London cartographer at a time when the Dutch dominated the world of mapmaking. It was also a time when New York was of little importance relative to other British colonies, particularly the islands of the West Indies, where sugar plantations worked by enslaved peoples created enormous wealth for Britain.Real progress in mapping New York City was not made until the time of the American Revolutionary War, when the British seized New York City and Lord Howe, the Commander of the Royal Navy in North America, found that new, more accurate and precise maps and nautical charts were needed to help ensure the safety of British ships. One result was A chart of New York Harbour: with the banks, soundings and sailing marks from the most accurate surveys & observations. This new map was the work of two surveyors aboard Howe’s flagship, the HMS Eagle: Lieutenants John Hunter and John Knight. Remarkably accurate, it came to replace the Tiddeman Chart in the final editions of The English Pilot.View these maps here and here. Interested in seeing more maps from BHS’s collection? Visit our new online map portal.You can see more from the BHS collections in our online image gallery, which includes a selection of our images. We look forward inviting you back to BHS is the future to research in our entire collection of images, archives, maps, and special collections. In the meantime, please visit our digital collections, available here. Our reference staff are still available to help with your research! You can reach us at library@brooklynhistory.org.