Page:Euclid's Elements 1714 Barrow translation.djvu/361

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N the firt place we ought to et down (as a Foundation) what that is, which we call DATUM or GIVEN; then to conider the Profit and Utility thereof; and in the third place, to what Art or Science this Tract doth appertain. The Word DATUM therefore is diverly defined, for the Antients have defined it after one manner, and later Writers after another, whence it follows that it eemeth a difficult thing to give a true Explication thereof; for ome of them have not delivered the Definition of the Word; but have with much Labour and Trouble ought certain Proprieties thereof, and ome others collecting and mingling what hath been