Crown glass

Definition and stakes

Various Popular Science Monthly (1889)

Both sheet and crown glass owe their origin to the blower's breath. Though they are less brilliant than the plate, their methods of fabrication are much more interesting, since they involve a far greater amount of manual dexterity on the part of the artisans. It is, indeed, difficult to know which to admire the more, the chemistry or the physics of the operation; the nicety with which the glass-maker regulates the proportions of his charge so as to produce this beautifully clear substance, or the skill with which he subsequently handles the finished glass and adapts it to our uses.
Source: Wikisource

Anonymous The Useful Arts Employed in the Construction of Dwelling Houses… (1851)

The glass with which windows are generally glazed, is called Crown glass. It is formed of different materials in different manufactories. In some instances the materials consist of fine white sand, carbonate of lime, carbonate of soda, and clippings or waste pieces of old glass; while in other cases they consist of white sand, pearl-ash, saltpetre, borax, and arsenic, in certain proportions. On this point we shall not dwell, for almost every manufacturer has a favourite receipt of his own. Whatever substances are employed, they are intimately mixed before being melted.
Source: Gutenberg

Anonymous The Useful Arts Employed in the Construction of Dwelling Houses… (1851)

Indeed, the management of the heat in the manufacture of crown glass requires so much care and skill that few workmen produce an article of the same value, even though working at the same furnace; hence crown glass is known in the market as firsts, seconds, thirds, and fourths; the fourth quality producing less than one-half of the price of the first.
Source: Gutenberg

Get perspective with Kwize: daily news enlightened by great literature