Three numbers and a letter.

221B.

Three numbers, one letter. Four characters that signify . . . what?

An address . . . no, more than that. Poems aren't written and conventions aren't concocted based on a location. When we well remember a site, it's usually because something significant happened there. Troy. Waterloo. Gettysburg. Or it's a place of power. 10 Downing Street. 1600 Pennsylvania Avenue. 30 Rockefeller Plaza. But most lists of famous addresses contain 221B Baker Street as well.

Site of a significant event? Place of power?

You could make a case for either, but those things are not what "221B" evokes.

The most important events in the detective career of Sherlock Holmes, with few exceptions, just didn't happen there. Clients telling their stories were key, of course, but not the sort of climactic moment that sticks with you.

"221B" is almost binary in its makeup, and that's where you start getting to the heart of things. Since "B" is the second letter of the alphabet, it's really all twos and a one instead of ones and zeroes. The one is the odd character in there, almost standing alone to make itself more significant. Because you need that, now and then, to really show how important two of something can be. "222B" just never would have done it, really.

It's pretty obvious that 221B has come to signify a partnership that brought us some of the greatest detective stories of all time. Maybe the one stands for the first and foremost consulting detective the world has ever known. Maybe the "B" stands for his . . . best friend? Analyzing the make-up of "221B" as a symbol for partnership is just two weirdly simple. Yet there it is.

221B Baker Street is less of an address and more of a period of time. Whoever lived there before Sherlock Holmes and Dr. Watson is irrelevant. Whoever came after, equally so. The seventeen years that Sherlock Holmes operated out of Baker Street with John H. Watson at his side align perfectly with the seventeen steps that led up to that flat, and that period is the location in space and time that 221B will always represent, even without the "Baker Street."

There's something very special about that. Cold numbers and a single letter of the alphabet evoking a bond between two men living lives of discovery, adventure, and justice-dealing. And so much more, so much that we have spent over a century in study of it, and will surely spent a great many years more. Of all the words written by the creator who gave us those amazing records, none will probably ever have the full power of "221B," unless it's that very unique first name of the very unique figure who first thought to rent the place.

A better sigil no tribe could hope to have, and we are that lucky tribe.

Three numbers, one letter. 221B.