Henri Guinand four de fusion avec appareil à guinander, 1840

Henri guinand (1771–1851): furnace for melting optical glass. P = stirring flask ("guinand") invented by his father pierre-louis guinand (1748–1824) and modified by the author to avoid streaks and bubbles. Description of the process of making flint-glass; by m. Guinand, rue mouffetard, 283. In: bulletin de la société d'encouragement pour l'industrie nationale (paris) 39/1840, pp. 468–472, here: p. 468/fig. 3. Date: 1840.