621.3
   F
        Foster , Horatio Alvah , 1858-1913 . Electrical engineer ´  s pocket-book : a Handbook of useful data for electricians and electrical engineers . By Horatio A . Foster . With the collaboration of eminent specialists . 7th ed . ; rev . New York , D . Van Nostrand company , 1910 . xxxvi , 1599 p . ilus . , tablas , diagrs . 17 cm .