 Fourthly, water was pushed up into the engine only by atmospheric pressure (working against a condensed-steam 'vacuum'), so the engine had to be no more than about above the water level – requiring it to be installed, operated, and maintained far down in the dark mines all over.Savery's original patent of July 1698 gave 14 years' protection; the next year, 1699, an Act of Parliament was passed which extended his protection for a further 21 years.This Act became known as the "Fire Engine Act".