the british rail class 70 was a class of three 3rd rail co-co electric locomotives. the initial two were built by the southern railway at ashford works in 1941 and 1945 and were numbered cc1 and cc2. electrical equipment was designed by alfred raworth and the body by oliver bulleid. cc2 was modified slightly from the original design by c. m. cock who had succeeded raworth as electrical engineer. the third was built by british railways in 1948 and numbered 20003.