We say know, English people say nao; we say cow, the Briton says kaow; we—” “Oh, come!
— from Alonzo Fitz, and Other Stories by Mark Twain

In the preparation of this portion of the work, free use was made of the writings of standard authors upon Elocution, such as Walker, McCulloch, Sheridan Knowles, Ewing, Pinnock, Scott, Bell, Graham, Mylins, Wood, Rush, and many others.
— from McGuffey's Sixth Eclectic Reader by William Holmes McGuffey

For psychotherapeutics, he must, if he would be successful, know every possible source of worry and annoyance and, as nearly as may be ascertained, every slight phase of physical fatigue that may be a disturbing factor in his patient's life.
— from Psychotherapy Including the History of the Use of Mental Influence, Directly and Indirectly, in Healing and the Principles for the Application of Energies Derived from the Mind to the Treatment of Disease by James J. (James Joseph) Walsh

Syn. - Keen; eagleÐeyed; penetrating; skilled; discriminating; cunning; sagacious; subtle; wily; crafty.
— from Webster's Unabridged Dictionary (1st 100 Pages) by Noah Webster