Other elements of the problem there are none, except mere numbers and angles, which do not depend upon the fundamental measurements of space, time and mass.
Flamsteed, in the first volume of the Historia coelestis, has inserted a series of measurements made by Gascoigne extending from 1638 to 1643.
(1773), p. 190) also gives results of measurements by Gascoigne of the diameters of the moon, Jupiter, Mars and Venus with his micrometer.
Delambre gives 3 the following comparison between the results of Gascoigne's measurements of the sun's semi-diameter and the computed results from modern determinations: Gascoigne.
This determines the reading of the position-circle corresponding to position-angle 90° or 270 °.2 When it is remembered that the measurements of the Struves, Dembowski, Secchi, the Bonds, Maclear and of most modern European astronomers have been made with Fraunhofer or Merz micrometers it is not too much to say that fig.