“ Life turns the winch, and fancy or accident pulls out the stops. ”
 Oliver Wendell Holmes Sr., The Autocrat of the Breakfast-Table (1858). copy citation

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“—I don’t know that I may not bring the Poet here, some day or other, and let him speak for himself. Still I think I can tell you what he says quite as well as he could do it.—Oh,—he said to me, one day,—I am but a hand-organ man,—say rather, a hand-organ. Life turns the winch, and fancy or accident pulls out the stops. I come under your windows, some fine spring morning, and play you one of my adagio movements, and some of you say,—This is good,—play us so always. But, dear friends, if I did not change the stop sometimes, the machine would wear out in one part and rust in another.” source