Doonesbury by Garry Trudeau for July 28, 1999
MacArthur: Looks like there's a break in the action, sirs... Chase: Are you sure, MacArthur? After all, we've only been subjected to raw sewage, tour boats, barracudas, torrential showers and...and... Mark: We're reasonable men, MacArthur. So we know this isn't snow. MacArthur: Quite right, sir. It's volcanic ash.