The Collaborative International Dictionary of English v.0.48:

Instructive \In*struct"ive\, a. [Cf. F. instructif.]
   Conveying knowledge; serving to instruct or inform; as,
   experience furnishes very instructive lessons. --Addison.
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         In various talk the instructive hours they past.
                                                  --Pope.
   -- In*struct"ive*ly, adv. -- In*struct"ive*ness, n.
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         The pregnant instructiveness of the Scripture. --Boyle.
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