Although the forward pass had been used earlier, it was only legalized by rule changes in 1906. The idea was to encourage a more wide open game which, hopefully, would be a safer game.
The 1906 Spalding’s Guide set forth new Rule 14:
(a) A player may throw, pass, or bat the ball in any direction except toward his opponents’ goal. penalty – Loss of 5 yards.
EXCEPTION- (1) One forward pass shall be allowed to each scrimmage, provided each such pass be made by a player who was behind the line of scrimmage when the ball was put in play, and provided the ball, after being passed foward, does not touch the ground before being touched by a player of either side.
PENALTY—(1) If a forward pass be made by a player who was not behind the line of scrimmage when the ball was put in play, the ball shall go to the opponents on the spot where the pass was made. If the ball, after being passed forward, touches the ground before being touched by a player of either side, it shall go to the opponents on the spot where the pass was made.
EXCEPTION—(2) The pass may not be touched by a player who was on the line of scrimmage when the ball was put in play except by either of the two men playing on the ends of the line.
PENALTY—(2) If a forward pass is unlawfully touched by a player who was on the line of scrimmage when the ball was put in play, it shall go to the opponents on the spot where the pass was made.
EXCEPTION—(3) A forward pass over the line of scrimmage within the space of 5 yards on each side of the center shall Be unlawful.
PENALTY—(3) If the ball is passed over the line of scrimmage within the space of 5 yards on each side of the center, it shall go to the opponents on the spot where the pass was made.
EXCEPTION—{If) A forward pass by the side which does not put the ball in play in a
scrimmage shall be unlawful.
PENALTY—(4) If a forward pass is made by the side which did not put the ball in play in a scrimmage, the ball shall go to the opponents on the spot where the pass was made.
EXCEPTION—(5) A forward pass which crosses the goal line on the fly or bound without touching a player of either side, shall be declared a touchback for the defenders of the goal.
To properly enforce this rule required a true gridiron with lines both parallel and perpendicular to the Goal lines. This post card of Yale’s football field illustrates how the field was laid-out back in 1907.
