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COMPARATIVE POWER OF BACK-GEARED MILLS.
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Size of Mill|4-ft.|6-ft.|8-ft.|9-ft.|10-ft.|12-ft.|14-ft.|16-ft.
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Horse-Power |1/12 | 1/5 |3/10 | 2/5 | 3/5 | 1 | 1-3/5|2-3/5
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