(And since Blogger's been such a charmer lately, you might be better off in several ways by double-clicking on the videos below to allow them to open in their own windows...full view of them, and quite probably less stuttering.)
So, the Byrds. Not too forgotten, as probably the most protean and innovative of the sustainedly popular US rock bands of the 1960s...certainly even such rivals as the Beach Boys, Jefferson Airplane, the Band (with or without Dylan), and (the initially anti-popular) the Velvet Underground didn't cover as much territory, explore as many ways of making various sorts of rock music, often at the pioneering edge of such forms as folk-rock, jazz-rock, and country-rock (in the latter-day form, anyway, as opposed to rockabilly).
And no song of theirs is more iconic than Gene Clark and Roger/Jim McGuinn's "Eight Miles High"...a song about their first tour of England, the flight over (and Clark's acrophobia, which alas forced him to quit the band, depriving the Byrds of their best songwriter by any measure), and, as every idiot censor at the end of 1966 Just Knew, getting high. Well, as a sort of pun, anyway...as this was also McGuinn's most thorough expression for free jazz (though the album Fifth Dimension would also feature the similar, nearly as good "I See You"), particularly that of John Coltrane, who knew and was consistently further investigating spiritual highs via music as well. Even the British jazz-loving rock bands, the Zombies and Yardbirds and Animals and all, hadn't quite caught up with what was Happening Now in jazz to the same extent, and while the two songs were early steps, they were assured early steps...and also on the way toward realizing McGuinn's desire to make what he metaphorized as "jet" music, as opposed to older forms. Certainly the jazz fusion bands, coming from the other direction, were mostly several years off, as well.
"Eight Miles High" (remastered)
"Eight Miles High" (alternate take/mix)
"I See You":
The syndicated public broadcasting series Growing Bolder offered its viewers an interesting interview and showcase for McGuinn's home movies of that first British experience for the band, and here it is, with an "Eight Miles High" as soundtrack in the middle, along with snatches of other Byrds and Beatles recordings also heard: