antique hand-crank vintage, Western Electric early telephone component, 1914 patent date

Early old antique, porcelain and brass Western Electric telephone component. This is marked Western Electric on the round porcelain socket and carries a 1914 patent date on the brass cover. We've been told that this is a telephone line lightning arrestor. The two porcelain blocks are marked "L" (for LOAD) at each terminal. This measures about 9" long and is mounted on a primitive weathered old board.