This script was featured in the recently published book, Artistic Printing. It's labeled as "Indestructible Script" circa 1895. Appears to have been created by the Indestructible Type Company, of Chicago, patent pending Lindsay Type Foundry.
I've searched high and low (What the Font + every major & not-so-major foundry I can think of) and haven't found this script anywhere! Surely something this lovely hasn't died, or has at least been resurrected?