Pass The Hat Meaning

Example : 1885, Mark Twain, Huckleberry Finn, ch. 20:  Then somebody sings out, "Take up a collection for him, take up a collection!" Well, a half a dozen made a jump to do it, but somebody sings out, "Let HIM pass the hat around!"2008 Dec. 5, Martha Ann Overland, "In Asia, American-Style Fund Raising Takes Off," Chronicle of Higher Education (retrieved 11 Dec. 2008):  The institutions are opening development offices, hiring professional fund raisers, investing in slick billion-dollar campaigns, and trotting out their presidents to pass the hat.