Disc of flint glass; Chance, Brothers, and Co. Photographer: Ferrier, Claude-Marie
Scope & Content:
View of the large piece of optical glass, 29 inches in diameter, exhibited by Chance Brothers. On first inspection by the jury, no opinion could be given as to its quality because of unevenness of the surface. After polishing, it was again examined and finally won a Council Medal, although the j...
Arrangement of several specimens of 'astronomical glass' of various sizes, manufactured by Theodore Daguet of Switzerland: '…They were all found to be good … Mr. Daguet, by a process of his own, gives to flint glass a degree of hardness not attained by any other manufacturer; his glass, particul...