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 20
that moving electric charges produce magnetic fieldsin which the lines of magnetic force enclose circles in planes at rightangles to the direction of motion of the moving charges. This has beenproved to be true for single static charges.* ELECTRO-MAGNETIC INDUCTION. 12. Fig. 11 represents a primary… … A B of this wire is parallel to, and at a distance from another conductingwire C D. When the break at K is closed, a current flows in the circuit,and a field of force is created around the wire. Let ys consider thestraight portion A B in which the direction of the current is shown bythe arrows, and…
