Mark Twain’s Address

One day at the Knickerbockers Club in New York, a group of Mark Twain’s friends recalled that it was his birthday, and decided to write him a collective letter. They composed seven or eight pages of nonsense and, since they did not know offhand where Mark was, addressed it:

Mark Twain
Lord Knows Where

Several months elapsed when a postal addressed to them was received, bearing this message:

He did. Mark Twain