Gear's illustrated catalogue of wood and iron working machinery (1872)
A.S. Gear, Gear, A. S · Boston : Printed at A.S. Gear's printing office, 62 Sudbury Street · leaf 397
ed volume of tone. By the formation of the bridge in theshape of a ring to right or left, reversed to its original direction, a further elongation was obtained, and the unavoidableinterruption of the several bridges, as formerly used, is entirely done away with. This construction, in connection… … 12 Description of Steinway & Sons Patented Inventiotts. No. 8—PATENT REPETITION ACTION, WITH SPRING BACK CHECK, APPLIED TO ACTIONS OF SQUARE PIANOS. This action is made serviceable also for grand pianos, through the pull of a spring counterbalancing the weight ofthe hammer; the back-check being…
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