An explanation of a new construction and improvement of the sea octant and sextant, containing, A most easy, expeditious and accurate Method of adjusting and rectifying those Instruments for Use both at Sea and Land. Also the best Disposition of the Glasses; with Directions for making the Fore and Back Observations; and the several Steps in the Process of finding the Longitude at Sea. Illustrated by four Copper-Plates. By B. Martin.

People / Organizations

• Benjamin Martin (Author)

Imprint

London: printed for the author, at No. 171, Fleet-Street, [1775?]

Publication year

1775-1775

ESTC No.

T25321

Grub Street ID

257762

Description

[2],37,[1]p., fold.plates ; 8⁰

Note

"The public are indebted solely to my son, J.L. Martin, for the invention .." (Preface); he was awarded patent no. 1088 in 1774.

Price from imprint: price 1s. 6d.