Edmund March Blunt (1770-1862) opened a nautical bookstore in Newburyport,
Ma., in 1793, published the first edition of The American Coast Pilot in
1796, and the first edition of The Practical Navigator in 1799. In 1802
he brought out the first edition of The New American Practical Navigator, the landmark book by Nathaniel Bowditch that taught countless Americans how to observe with octants and sextants and how to determine longitude with the lunar distance method. Blunt moved to New York in 1802, opened a shop at the Sign of the Quadrant, published and sold nautical books and charts, and sold and repaired nautical instruments.
Edmund Blunt’s sons, Edmund (1799-1866) and George William (1802-1878)
opened their own shop in New York in 1824, trading as E. & G. W. Blunt and offering nautical books, charts, and instruments. After building a circular
dividing engine in the mid-1850s, the Blunts began advertising "Sextants,
Quadrants, &c. of American manufacture."
The firm became Blunt & Nichols in 1866, and Blunt & Co., in 1868. It was purchased by Frederick Eckel, a German immigrant, in 1873.
Ref: Harold Burstyn, At the Sign of the Quadrant (Mystic, CT, 1957).
Description of E. & G. W. Blunt’s Dividing Engine (New York,
1857).