Twentieth century handbook for steam engineers and electricians, with questions and answers; a practical nontechnical treatise .. (1916)
Swingle, Calvin F. (Calvin Franklin), b. 1846 · Chicago, F.J. Drake & company · leaf 1483
trips of leadimmersed in dilute sulphuric acid. When current is sent 1448 Steam Engineering through them one plate turns a dark brown color, md theother a grey color. After an hours 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. Remove the chargingwires and connect to anything…
