Sextants were used for coastal mapping though, albeit specialized ones called hydrographic sextants. You can see one here: https://sextantbook.com/2019/01/13/a

Sextants were used for coastal mapping though, albeit specialized ones called hydrographic sextants. You can see one here: https://sextantbook.com/2019/01/13/a-french-hydrographic-sextant/ https://sextantbook.com/2019/01/13/a-french-hydrographic-sex... The linked article is by W.J. Morris, and his book on sextants is in my opinion one of the standard works and much recommended.