from John Kreiser of NHL.com,

The NHL officially changed forever on June 5, 1967, though not without a few anxious moments along the way.

The six new teams -- the Pittsburgh Penguins, St. Louis Blues, Los Angeles Kings, Minnesota North Stars, California Seals and Philadelphia Flyers -- became full-fledged members by handing over checks for $2 million apiece to one of the Original Six teams by the 2 p.m. deadline.

However, the money from the Flyers nearly didn't get there on time.

A power failure disrupted communications between the Fidelity Bank of Philadelphia, which was going to send the $2 million from the Flyers, to the Royal National Bank of Canada in Montreal....

The money arrived after phone lines from New York were used to work around the power problems, Putnam and Lou Scheinfeld, the fledgling Flyers vice president of business operations, got the check to NHL president Clarence Campbell just before the deadline and the Flyers (whose check went to the Toronto Maple Leafs) were officially in.

"I hope that by this time next year, we have reason to congratulate ourselves," Campbell said after the NHL officially doubled in size. He said all arena requirements had been met, proof of solid financing had been provided and that territorial rights of some minor leagues and teams would be met.

The new teams were placed together in the West Division, with the established teams forming the East Division. The length of the season, which had been 70 games since 1949-50, was raised to 74 for 1967-68, with each team playing the others in its own division 10 times and those in the other division four times.

All of a sudden, the NHL really was a "national" league.

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