Anthony Panizzi, the British Museum's chief librarian, designed the original round Reading Room around a problem that had nothing to do with the dome everyone remembers: how do you serve thousands of readers, each wanting a different obscure item, out of a collection too large for any of them to browse directly? His answer was a room organised entirely around a single central catalogue, with the books themselves stored out of sight, retrieved on request.
Closed stacks as a deliberate trade
Closed stacks feel restrictive to a modern visitor used to browsing open shelves, but Panizzi's system made a specific trade: readers gave up serendipitous browsing in exchange for a collection that could grow far larger, and be searched far more precisely, than open shelving would allow. The catalogue became the actual interface to the collection; the physical books became, in effect, a storage backend the reader never touched directly.
The dome served the catalogue, not the other way around
The famous domed ceiling wasn't built for spectacle first; the circular plan let the catalogue desk sit at the exact centre, equidistant from every seat, minimising the distance between a reader's question and the one person positioned to answer it. Function produced the form later celebrated purely as beauty — a sequence worth noting whenever a striking piece of digital design gets credited for its looks rather than the retrieval problem it was actually built to solve.
The dome is remembered. The catalogue desk at its centre is why the dome needed to be round in the first place.
Every system that separates "where things live" from "how you find them" is quietly Panizzi's room, rebuilt in whatever material the century has on hand.