...His work was not mainly in the field of observational astronomy, andtherefore did not materially influence that branch of science... 
Simon Newcomb 「Side-lights on Astronomy and Kindred Fields of Popular Science」
...Refracting astronomical telescopes are now constructed on thisprinciple, it having been discovered that for observational purposesthey possess several advantages over the Galilean instrument...
Thomas Orchard 「The Astronomy of Milton's 'Paradise Lost'」
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exposure criticize conclusions
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