Carlisle Gas and Water Company (Pa.).

Incorporated in 1853 by a special act of the Pennsylvania legislature, the Carlisle Gas & Water Co. was Pennsylvania Power & Light's oldest predecessor.

The Borough of Carlisle, Cumberland County was one of the company's major stockholders and represented on the board of managers. In 1855, the firm constructed a gas plant and distribution system and negotiated a street lighting contract with the borough. Within a few years its residential lighting business was flourishing and the company used its surplus capital to build a dam and hydroelectric plant on Conodoquinet Creek.

The introduction of incandescent electric light posed a serious threat. In an attempt to meet this challenge, in 1878 the company installed a water gas plant which enabled it to manufacture gas more economically. By the next decade it became obvious that gas would never be able to compete with electricity and Carlisle Gas was thus forced to diversify. In 1887, it erected an electric generating station which utilized two Thomson-Houston arc dynamos. After the company introduced an alternating current system in 1895 business grew rapidly. In 1912 it built a modern hydroelectric plant and formed a wholly owned subsidiary Carlisle Light, Heat and Power Company which managed the firm's electric generating and distribution system. In 1925 Lehigh Power Securities Corp. acquired the Carlisle companies and merged them into Pennsylvania Power & Light.