Appletons' cyclopaedia of applied mechanics: a dictionary of mechanical engineering and the mechanical arts (1880)
D. Appleton and Company, Benjamin, Park, 1849-1922 · New York, D. Appleton · leaf 439
420 MILLSTONES. lastly, it is sought to introduce the necessary quantity of air by means of pretty deep furrows on theface of the burr. The short furrows also serve this purpose in part, and are rightly called air-furrows.The quantity of flour produced is said to be largely increased by…
Mechanical engineering -- Dictionaries
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