Editing 1720 in science (section)

==Technology==
* A [[theodolite]] is developed by [[Jonathan Sisson]] of England.
* [[Pinchbeck (alloy)|Pinchbeck]] is invented by English watchmaker [[Christopher Pinchbeck]]; it is an [[alloy]] of 83% [[copper]] and 17% [[zinc]], creating a strong, hard-wearing metal which has the appearance and weight of 20 [[Carat (purity)|carat]] [[gold]].
* An early [[chronograph]] is invented which has only mechanical parts in it.
* Henry de Saumarez (of the [[Channel Islands]]) produces an instrument called the ''Marine Surveyor'' intended to measure a ship's [[velocity]].<ref>{{cite journal|first=A. H. W.|last=Robinson|title=Forum|page=358-40|journal=Journal of Navigation|volume=9|year=1956|doi=10.1017/S0373463300036493|doi-access=free}}</ref>
* A single-action five-[[pedal harp]] is developed by [[Jacob Hochbrucker]] of [[Bavaria]] which can raise the pitch of the selected strings by a half step.
* ''approx. date'' – Joseph Williamson uses a [[differential gear]] in a clock.