Brian Eno published his diary from 1995, called A Year with Swollen Appendices. It was published as a book in 1996 by Faber and Faber in the UK. That was the year that Eno worked with U2 on Original Soundtracks 1, and the book makes mention of a number of demos and working titles throughout. “Theremin” is one of the songs included in the book.
On June 6 Brian Eno wrote: “Played through existing material, I suggested dropping ‘Heaven’ and ‘Theremin’. No need to spend time on stragglers (but, as usual, it’s the stragglers that get all the time!).”