Until the late 1920s, football did not have consistent referees’ signals to indicate the happenings on the field. Few referees signaled the nature of penalties; other routines differed by individual or region.
F. A. Lambert, who often worked Big Ten games, published Football Officiating and Interpretation of the Rules in 1926, which included a lengthy discussion of how to assess whether to bring the chains onto the field and the procedures for handling a close measurement. If the measurement confirmed the offense had gained a first down, he recommended the referee signal the first down by “waving with the arm above the head and one finger “up” for the lines to be moved.”
Nowadays, referees face toward the defense, thrusting their arm downfield with their hand open. Either signal would work since neither is inherently better than the other. Still, this is a simple example of an element of the game we take for granted that was not always so.
For additional reading on the evolution of penalty signals, check out:
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