No material advance was made on Ptolemy's instrument until Tycho Brahe, whose elaborate armillary spheres passing into astrolabes are figured in his Astronjmiae Instauratae Mechanica.
Archimedes concluded from his measurements that the sun's diameter was greater than 27' and less than 32'; and even Tycho Brahe was so misled by his measures of the apparent diameters of the sun and moon as to conclude that a total eclipse of the sun was impossible.'
When Napier published the Canonis Descriptio England had taken no part in the advance of science, and there is no British author of the time except Napier whose name can be placed in the same rank as those of Copernicus, Tycho Brahe, Kepler, Galileo, or Stevinus.
Tycho Brahe, Astronomiae Instauratae Mechanica; M.
Century B.C.) and Aratus (3rd century B.C.); Ptolemy and Tycho Brahe catalogued 28 stars, Hevelius gave 29.