Twentieth century hand-book for steam engineers and electricians with questions and answers; a practical non-technical treatise .. (1913)
Swingle, Calvin Franklin, 1846- [from old catalog] · Chicago, F. J. Drake & company · leaf 1477
rips of leadimmersed in dilute sulplmric acid. When current is sent 1448 Steam Engineering through them one plate turns a dark brown color^ md theother a grey color. After an hour^s passage of currentreverse the connection and charge the other way. Theplates will change color—the grey one becoming… … begins to gas or boil. This is the signal to reverse the cur-rent as the cell is charged. When the cell takes several hours to gas it is in condi-tion to use. After one of the reversals continue to charge until cellhas gassed about fifteen minutes. Eemove the chargingwires and connect to anything…
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