1 NOTE:—The "front" end means the end at which the commutator is located. Armatures are most conveniently regarded from this end, the opposite end being known as the "back" end.

2 NOTE—The term back pitch means the number of spaces between the two inductors of a coil. For instance, in fig. 267, the pitch is 3; that is, there are three spaces between say inductors 1 and 4 which form part of the coil A—1—4—C. It is called the back pitch in distinction from the front or commutator pitch, which in this instance is 2.

3 NOTE—A re-entrant winding is one in which both ends re-enter or lead back to the starting point; a closed winding.