Wakened this morning, about three o’clock, by Mr. Griffin with a letter from Sir W. Coventry to W. Pen

So begins today’s installment of The Diary of Samuel Pepys, as rendered by Phil Gyford. It’s a remarkable project that maps January 1, 1660 (the start of Pepys’ famous diary) to January 1, 2003 (the start of Phil’s Moveable Type recreation of the diary) and has continued faithfully ever since.

The Pepys blog is enhanced in all sorts of useful ways. People, places, and topics are cross-linked with indexes, places are mapped, all references are viewable on a timeline — it’s a brilliant example of advanced blog customization.

Back in 2003 I mused about what kind of content management system would enable somebody to do a project like this without a lot of inspired hacking. The question came up again recently when my sister Ruth decided to recreate an archive of letters that my parents wrote home from our 15-month stay in New Delhi during 1961 and 1962.

I’ve long held that blog publishing systems are really lightweight content management systems that can be used for almost any purpose. So I pointed her to WordPress.com, explained that you can use pages instead of posts to arrange items however you like, and waited to see what would happen.

Well, it didn’t work. It’s true that you can build an arbitrary collection of pages, but there’s no way Ruth would be able to manage that collection without automation. I could write code to help her, but I don’t want to. That’s partly laziness, and partly curiosity about how to use the standard kit to achieve the desired effects.

One of the biggest limitations of pages, in WordPress, is something I’d never noticed until now: No tags! So ended my plan to have Ruth use tags on pages to achieve a lightweight version of Phil Gyford’s indexes.

Why not just use posts? Originally I thought it would be cool to mimic the Pepys diary: start with a date in 1961, and continue in “real” time. But Ruth doesn’t want to do it that way. She wants to be able to process the archive in any order that’s convenient. And she wants it to read forward, like a book of letters, not backward like a blog. These perfectly reasonable requirements turn out to be harder to satisfy than you’d think.

It turns out that you can make the letters run forward on the Posts page by manipulating the publication dates. So here was the scheme I tried first:

July 2 1961 -> Jan 01 1961 15:01
July 4 1961 -> Jan 01 1961 15:00
...
Oct 19 1961  -> Jan 01 1961 04:01
Oct 22 1961  -> Jan 01 1961 04:00

In this scheme, every letter maps to the same day, chosen arbitrarily as Jan 1, 1961. Every month maps to an hour of that day, each letter maps to a minute within that hour, and the times run backward. Since WordPress reverses the sequence again when displaying items on the Posts page, that makes time run forward in that view.

The benefits are huge. Now Ruth can use tags to organize sets of letters, imposing as much or as little structure as she wants. Views by tag are neatly presented as sets of blurbs with “Continue reading” links. Each item automatically links to its predecessor and successor.

But there’s irreducible weirdness too. For example, the Jan 01 1961 date — which has now become an abstract database key used only for sorting — is part of every post URL. You wind up with patterns like this:

/1961/01/01/june-30-1961-from-anita/

This gets even weirder because dates prior to the start of Unix time — Jan 1, 1970 — don’t display in the management UI. However that turns out to be both a feature and a bug. It’s a feature because WordPress reverts to the current date for display, so you see “Posted on June 28, 2010 by Ruth” instead of “Posted on January 1, 1961 by Ruth.” And it’s a bug because you can’t easily scan and adjust the dates that control sorting.

More weirdness arises from the deeply hardwired assumption — in WordPress, but also in all blogs, really — that entries post in reverse chronological order. Although the backwards time mapping seemed at first glance to work, it turned out to be broken in two ways. On the Posts page, after the break, the link pointed to “Older entries” which were really, in our scheme, “Newer entries.” And within posts, the next and previous logic was also reversed.

So for now I’ve gone back to a forward mapping of hours and minutes within Jan 1, 1961. I’ve ditched the default Posts page in favor of a hand-crafted page that presents items in ascending order. Once you’re in an item, the next and previous links work as expected because, when you move from item to item, WordPress uses a forward arrow of time.

I’m not complaining. It’s astonishing that WordPress provides a free service that Ruth can use publish this archive of letters, and I’m hugely grateful. I think we’ll be able to come up with a technique that will satisfy her requirements — without demanding heroic effort from her or custom software from me. But it sure is interesting to see what happens when you mess with a blog’s notion of the direction of time.