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 32
al, as in fig. 17a, the lines of force included will be the maximumnumber possible in that field, so that a revolution of 90° will make anentire change in the number of lines of force passing through therectangle. For instance, if the revolution is in the direction of the hands of aclock—i. e., if…
