On land, the period from the development of telescopes and pendulum clocks until the mid 18th-Century saw a steady increase in the number of places whose longitude had been determined with reasonable accuracy, often with errors of less than a degree, and nearly always within 2-3°.
Fal akal, ɣur azzaman wan efes n telescope tan d muntar tan pendulum har tazune n awatay wan 1800 issewad iddikud n idagan wi s tišijrit nasan tiskat s aqqud n tiditt , alwaq iyyan ahan marsalan id oraknen i degre s harkuk illan jir 2 d 3 °