The fun is just beginning with Biden. It will get better.
http://www.takeourword.com/Issue063.html
From Pat Burns:
What's the origin of as clean as a whistle?
Famed Scottish poet Robert "Rabbie" Burns (in his Author's Earnest Cry, 1786) provides us the first use of anything resembling the phrase clean as a whistle in writing: "Her mutchkin stowp as toom’s a whissle" For those readers not fluent in Lowlands Scots, this meant "Her pint bucket is as empty as a whistle". As a pair of dyed-in-the-wool penny-whistlers, we conjecture that Rabbie was familiar with this instrument, the implication being that if a whistle is not clear of obstruction inside, then it will not play properly.
Some have suggested that as clean as a whistle actually derives from as clear as a whistle. That explanation has the "clear" form meaning "pure" (as the pure sound of a whistle) and suggests that it is not a large leap from "pure" to "clean". We have found nothing to support this notion, however. A writer in 1828 defines as clean as a whistle as "a proverbial simile, signifying completely, entirely" but we have to wait until 1880 before as clear as a whistle appears in print.
While researching this we turned up the delightful phrase box of whistles, a contemptuous, puritanical term for a church organ. Alsop, writing in 1678 said that "Pope Vitalian..first..taught Mankind the Art of Worshipping God with a Box of Whistles".