The Unbreakable Glass That Promised a Household Revolution
In 1877, a new chemical tempering process promised Seattle residents that lamp chimneys would never crack again—even if you drove nails with them.
A Frenchman has recently patented a process for increasing the durability of glassware, which is likely to effect a revolution in that branch of manufactures and prove of incalculable benefit to the world. The art consists in annealing the glass by plunging it into an oil bath, the exact composition of which is not divulged. The process with lamp chimneys is thus described: A workman, having in his hand a pole about six feet long, with a knob on the end the size of a lamp burner, fits a chimney on the knob and plunges it into the flame of a furnace. When the glass reaches a red heat, he quickly shoots it into one of a dozen small baths fixed on a revolving table. The effect of the process is to harden the outer shell of the ware, thus diminishing the brittleness. M. de la Chapelle, a proprietor of the process, demonstrated the strength of this treated glass by driving nails into a wooden board using a lamp chimney as a hammer. Another demonstrator, M. Muzard, smashed tumblers and finger glasses against the floor; they rebounded and rolled in all directions, but not one was broken.
“Do you think, said M. de la Chapelle, smiling, 'Here, Jean,' calling to a young Parisian, 'drive you a nail with this lamp chimney.'”
This 1877 report captures the Victorian obsession with industrial material science. While tempered glass eventually became a standard safety feature for our modern windows and smartphone screens, the extravagant public demonstrations of 19th-century 'miracle' products remind us that the hype cycle surrounding new technology is as old as the city itself.
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