Maybe the best Robert Plant vocal? Is that possible? In one song, he really ranges across everything he was amazing for: His warm low and middle registers, his psychedelic shrieks, his ear for timing, and his improvisation.
He never again had a ballad like this on which to shine. After this album, Led Zeppelin moved on from their phase of rustic folk inspired by their storied retreats to the Braun-Yr-Aur cottage.
Led Zeppelin III and IV are the albums devoted to this, just as Led Zeppelin I and II formed a couplet devoted to pure blues rock. Houses of the Holy and Physical Graffiti would form a new couplet of experimental, unique rock music that successfully charted new territory. Presence and In Through the Out Door formed a final couplet of mostly sucking.
The guitars and mandolin are so nice. Formally, there are no choruses, just beautiful guitar interludes. There is a great minor development section but no real ending, just a fade-out on the main, undulating chord.
A peaceful song in the midst of the band's manic peak.