Sentence:  However, although steam-powered machines were used in the 19th century also to <WSD>roughcast</WSD> and polish mass-produced lenses for everyday use of just a few centimeters in diameter (for glasses and lorgnettes, opera glasses and small cheap telescopes), those of the best quality, used mainly in optical equipment, were still manufactured and finished off by hand, one by one. 
Meaning of the word marked with <WSD> tags:  To shape crudely; to form in its first rudiments, without correction or polish.