Galileo's accuracy in measuring horizontal projections / Stillman Drake.
Abstract:
On the usual assumption that f. 116v recorded measurements of horizontal projections after terminal falls of 828 punti, Galileo is believed to have made experimental errors as great as 3 1/2% (or more when absolute rather than proportional calculations are adopted). Re-examination of the wording and the data on f. 116v indicates much greater accuracy of Galileo's measurements and throws new light on his study of horizontal projections. Its relation to his study of oblique projections downward is clarified. Evidence is presented that Galileo also considered oblique upward projection, obtaining a result he reported to Antonio de' Medici in February 1609
Annali dell'Istituto e Museo di storia della scienza di Firenze A. 10, fasc. 1 (1985), p. 3-14