Listening to the second album "A Saucerful Of Secrets" released in July 1968 in the USA. David Gilmour was added to the band. The idea was to keep Syd on board as a non performing (no live shows) member. The only song on the album with both Barrett and Gilmour. Song written by Waters.
Definitely my favorite Pink Floyd track. There's a delightful live recording of it included with the 'Immersion' box set of 'Wish You Were Here'. Overall, I think the version from Live at Pompeii is my favorite though.