They had to connect two canals at very different heights, and they didn't want to waste water by using locks. This is an incredibly practical way to do it. It's energy efficient, water efficient, and a brilliant demonstration of Archimedes principle.
And it's in the Geek Atlas. It's wonderful. Art, engineering and education.
Search for Falkirk and you'll find it's been mentioned here before.
I think the archimedes link is that boats in the lock displace their own weight in water, this means you can have two different weights of boat yet the two chambers will still counterbalance exactly.
I feel that you either have missed the point, or you're not explaining yourself clearly. Dismissing Archimedes' principle simply as "boats that float in water float in water" seems rather ingenuous.
Archimedes' principle says that the weight of water displaced by a floating object equals the weight of the object. The Falkirk wheel exploits this in a design-critical fashion. The chambers are full to the brim of water. When a boat enters the chamber, some of that water is displaced.
What's critical, though, is no matter how many boats are in a chamber, including none, the chamber still weighs the same. Hence the wheel remains balanced no matter how many boats are in it.
For those who don't know Archimedes' principle, and I've found even for many who think they do, this comes as a surprise.
"Why," they ask, "are the chambers still balanced?"
Perhaps you just think this is all obvious, in which case I concede your exceptional perception. And in my experience, exceptional it is.
Why the Falkirk Wheel remains balanced under apparently different loads is not obvious to most.
