American Shuttle Looms
This scan is taken from a 1904 Draper Company publication. The now-famous XX denim used on the original Levi's 501 production were woven on Draper looms at the Amoskeag Manufacturing Co. In fact, Levi Strauss & Co. historian, Lynn Downey, notes that the denim from their "first waist overalls came from the Amoskeag Manufacturing Company in Manchester, New Hampshire, on the East Coast of the United States." ("A Short History of Denim," Downey).
In as early as 1904 the Amoskeag Manufacturing Co. owned 1261 Draper Northrop looms (this does not even include other models of Draper looms Amoskeag had; please note not all Draper looms were used for making denim but to the extent of my research evidence most or even all denim looms at Amoskeag were from Draper who practically had a monopoly in loom-building at the time in America).
Today you can see the Model E at Cone Denim in Greensboro, North Carolina. I have not received full clearance to publish detailed info and media but here's a teaser.
Lynn Downey and LS&CO's "A Short History of Denim" (PDF Alert)
Cone Denim Website