Here you go (from Wikipedia):
Duane learned to play slide guitar on his birthday in 1968. He was recovering from an injury to his left elbow, caused in a fall from a horse. Gregg brought him a birthday present, the debut album by Taj Mahal, and a bottle of Coricidin pills. He left them on the front porch and rang the bell, as Duane was angry with him about the injury. "About two hours after I left, my phone rang," Gregg recalled. "'Baby brother, baby brother, get over here now!'" Duane had poured the pills out of the bottle and washed off the label and was using it as a slide to play along with the album track "Statesboro Blues" (on the recording, the slide guitar is played by Jesse Ed Davis). "Duane had never played slide before," said Gregg, "he just picked it up and started burnin'. He was a natural." (-quoted from:Muscle Shoals (film)). The song became a part of the Allman Brothers Band's repertoire, and Duane's slide guitar became crucial to their sound. Because of his use of the early-1970s-era Coricidin medicine bottle, which is no longer manufactured, replica Coricidin bottles are now popular with slide guitar players who like its glassy feel and sound.
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