A short 2004 essay by Brian Lemin on when and why East Midland lace bobbins began to be fitted with bead spangles. It reviews common theories (adding tension, preventing machine-spun thread from unwinding), cites early excavated bobbins and published sources, and compares spangled and unspangled bobbins by Joseph Haskins and other makers. He tentatively links the change to the introduction of machine-spun cotton thread between 1803 and 1833, and presents this as a contribution to the debate rather than a definitive answer.