A snippet of the history of the strong glass bottle. In 1633 Sir Kenelm Digby, was experimenting with glass production, and received a visit from a former manager of Sir Robert Mansell’s glassworks, James Howell. Digby knew Howell through his acquaintance with Mansell from Navy days although they were not friends. Howell wanted Digby to apply some of his wondrous Powder
of Sympathy to a wound he had sustained breaking up a duel. Astonishingly (from today’s perspective), the powder worked its magic and a friendship was forged.
They discovered that the heat of a coal fired furnace could be increased further by using tunnels to draw in oxygen and that the higher the temperature, strong glass could be produced. After the proclamation by James 1st in 1615 banning the use of charcoal several including Mansell had tried coal fired glass furnaces but could not make it successful. (to be fair, the flues were coupled with a change in formulation of the mix).
Under licence from Mansell who had had a former glassworks here at Newnham on Severn, Digby reopened and modified the furnace, making glass bottles for cider initially. The trade soon located to larger centres but there is still an area called Glasshouses and a public house in the area called the Glasshouse