Robison's Manual of radio telegraphy and telephony for the use of naval electricians (1918)
Robison, S. S. (Samuel Shelburne), b. 1867, United States Naval Institute, Todd, David Wooster, Hooper, Stanford Caldwell · Annapolis, Md. : The United States Naval Institute · leaf 27
-< c ->- D Fig. 14. 26. If the iron of fig. 14 is extended to include C D, as in fig. 14a, theeffect of changes in A B is increased still more, because in fig. 14 thelines of force are partly in iron and partly in air, while in fig. 14a theyhave an iron path throughout, and are consequently… … Fig. 14a.—Closed-Core Transformer (current in A B falling). <- ^
