Laurence Sterne - The Life and Opinions of Tristram Shandy, Gentleman (Chap. 4.49) lyrics

 An eye is for all the world exactly like a cannon, in this respect; That it is not so much the eye or the cannon, in themselves, as it is the carriage of the eye—and the carriage of the cannon, by which both the one and the other are enabled to do so much execution. I don't think the comparison a bad one: However, as 'tis made and placed at the head of the chapter, as much for use as ornament, all I desire in return, is, that whenever I speak of Mrs. Wadman's eyes (except once in the next period), that you keep it in your fancy.  I protest, Madam, said my uncle Toby, I can see nothing whatever in your eye.  It is not in the white; said Mrs. Wadman: my uncle Toby look'd with might and main into the pupil—  Now of all the eyes which ever were created—from your own, Madam, up to those of Venus herself, which certainly were as venereal a pair of eyes as ever stood in a head—there never was an eye of them all, so fitted to rob my uncle Toby of his repose, as the very eye, at which he was looking—it was not, Madam a rolling eye—a romping or a wanton one—nor was it an eye sparkling—petulant or imperious—of high claims and terrifying exactions, which would have curdled at once that milk of human nature, of which my uncle Toby was made up—but 'twas an eye full of gentle salutations—and soft responses—speaking—not like the trumpet stop of some ill-made organ, in which many an eye I talk to, holds coarse converse—but whispering soft—like the last low accent of an expiring saint—'How can you live comfortless, captain Shandy, and alone, without a bosom to lean your head on—or trust your cares to?'  It was an eye—  But I shall be in love with it myself, if I say another word about it.  —It did my uncle Toby's business.