The name Type Warmers JNL traces its lineage to small brochure brochures issued by Indianapolis' Cobb Shinn for his line of letterpress cuts; of which a couple of can be found included within this typeface.
Presumably type might "heat up to" these stock illustrations and work hand-in-hand to deliver the message, thus the "Type Warmers" sobriquet.
Originally understood for illustrating lots of attractive and funny postcards of the early 1900s, Shinn moved into the field of buying stock art and rearranging them as electrotypes or "cuts", the predecessor to today's digital clip art.
A number of the animations he sold can be found in the Shinn Kickers JNL font.
Font Family: Type Warmers JNL Regular