When Jerry Garcia died unexpectedly in August 1995, his Grateful Dead bandmate Bob Weir went right back out on the road to deal with the loss of his friend.

They met when Weir was 17 and Garcia was an older-and-wiser 22. For three decades, they'd perfected a rhythm-and-lead-guitar tandem that provided the essence of the Grateful Dead sound. In fact, the personal and musical chemistry between them was so strong, it always made me think of what trumpeter Dizzy Gillespie once said of saxophonist Charlie Parker: "He was the other half of my heartbeat."

Over the last two-plus decades, Weir stayed on the road, lending his name and sound to various partial Grateful Dead reunions — and one big official reunion last summer. He's also been touring almost constantly with a group of younger jazz-influenced players in a band called Ratdog. Weir has popped up on various stages to jam with younger musicians who were probably in diapers when Garcia died, effectively ending The Grateful Dead's run.

What Weir hasn't been doing was writing music, until now.

Not only is Blue Mountain (out Sept. 30) his first new album in a decade, but it also represents the first big batch of songwriting he's done in 30 years. It's billed as an emotional look back at time he'd spent in rural Wyoming as a teenager. There are references to cowboys, as well as acoustic guitars and the kind of looseness you might hear around a campfire under a blanket of stars.

The first track to be released from the album was written in collaboration with Josh Ritter. "Only A River" is an emotional reflection on life that references the 19th-century American folk song "Shenandoah."

I may be reading too much into it, but it sounds as if Weir is reaching out to his old pal through the song, which Garcia recorded with mandolinist David Grisman in an achingly beautiful version for their 1993 album Not For Kids Only.

Now 68, Weir has developed a storyteller's voice, complete with sonic wrinkles and grey hair — a far cry from the baby face we used to see on stage next to Garcia. So when he sings, "Shenandoah, I long to see you," it seems to cut right to an inevitable sense of loss. Yet "Only A River" isn't sad at all.

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