epochal

Observe, then, that Davy made his epochal experiment of melting ice by friction when he was a youth of twenty.

In the following year of 1871, Goodyear invented his welt shoe-sewing machine and Maddox made his epochal discovery.

Not too wide, however, for there were certain ones who must keep track of all details regarding this epochal event.

To-day she was facing the first problem of her young life, epochal.

Coronado had made one of the epochal explorations of all history.

The scene of this epochal enterprise was the region around Havana, particularly between Havana and Matanzas.

It was a bright morning; the week just ended had been, in a sense, epochal, and Wheaton resolved to go to church.

Pierre Curie himself declared that more than half of the epochal discovery belonged to his wife.

Historians recognize two epochal events in the life of the nation.

To us, alone and in peril, this diary assumed an epochal importance entirely out of kelter with its face value.