If you see the marking 4/4 on an old score it's not a time signature, but means 4 shillings and fourpence, which is what you are required to pay the copyright owner. If there is later a section marked 7/4 you must pay an additional seven shillings and fourpence to continue. 'Money' by Pink Floyd, being in 7/4, was a comment on songwriters that would put in bars of 7/4 in the middle of songs just to make some extra cash, such as Genesis, which is why Floyd never covered Genesis songs.
Note, all that King Crimson polyrhythmic stuff of the 1980s was actually written by Fripp and Belew in the 1970s when the practice was still in force. In this case they both wanted their 3 shillings fourpence and four shillings fourpence each, so just wrote it in both time signatures at once, costing a covering band 7 shillings and eightpence, split to Fripp and Belew. Unfortunately, decimilisation and complex transatlantic trade agreements meant that Belew was required to sue himself and leave King Crimson, and Fripp had to sue Belew, the Pope and the Dalai Lama.
