The Deacon's Masterpiece

I've always loved the 'Deacon's Masterpiece' reference in Weinberg's excellent Psychology of Computer Programming - it was

built in such a logical way
It ran a hundred years to the day.

I always imagined the 'Masterpiece' to be some kind of wonderful watch or clock that kept time far faster than necessary, and whenever I found a bug in my code, I'd think 'Yeah, I built it in such a logical way / It ran a hundred years to a day.'

So I'm a bit disappointed, having finally followed up the reference, to find that it's a just some rustic humour by Oliver Wendell Holmes about a 'wonderful one-hoss shay' - that's a chaise to us, one of those bouncy little horse-drawn carriages.