Here's some background for those interested. The Charley Jordan original is a little different. Paul Oliver quotes it (or from it - I don't have the recording and therefore do not know if it is the complete text) in his 'Songsters & Saints':

If you want to hear that elephant grunt
You can take him down to the river and then wash his trunk – now
Got him over, give 'im a Co-Cola
Lemon soda, saucer of ice cream
Take soap and water for to keep it clean

If you keeps it dirty and I keeps it clean
We don't know what keepin' it dirty means – now
You go over, get a bottle of Co-Cola etc

The terriblest sight I ever seen
Was the cook cookin' business and his hands wasn't clean – now
Yo go over, get a bottle of Co-Cola etc

You got a head like an owl, mouth like a goat
Every time you see me, lookin' for some soap
Now you go over, get a bottle of Co-Cola etc

[Charley Jordan 'Keep It Clean' Vocalion 1511. Recorded in Chicago circa mid-June 1930].

Oliver comments that Jordan's line 'We don't know what keepin' it dirty means', embracing himself and the record listeners, emphasises his identification with the audience and their familiarity with a body of bawdy songs that were widely known - 'Dirty Mother Fuyer', 'The Dozens', 'Sweet Petuni', 'Shave 'Em Dry', 'The Ma Grinder', 'Just a Spoonful', 'Shake It and Break It' etc.

Jordan was born in 1890 in Mabelville, Arkansas, served in WWI and later hoboed and worked the medicine shows until a bullet in the leg, occasioned by an argument over his manufacture of illegal liquor, confined his activities to St Louis.

--Stewie.