Prism and Lens Making

摘要: THE literature relating to modern methods of glass grinding and polishing is scanty, perhaps because this traditionally a hand craft, differing little in essentials from the practice three hundred years ago, each worker guards jealously handed down him as valuable professional secrets. Though machines for were projected by Descartes others, there no record these being successful until Lord Rosse constructed machine making his large astronomical reflectors ; reciprocated polisher on revolving work seems have standardized stroke, regarded only one satisfactory accurate 'figuring' late Mr. W. Taylor, twenty-nine showed feasibility more efficient round-stroke machine. Prism Lens Making A Text Book Optical Glassworkers. By F. Twyman. Pp. iv + 178. (London : Adam Hilger, Ltd., 1942.) 15s. net.