Belle and Stewart, a pair of rare peregrine falcons, have been living on the 55th floor of the Washington Mutual Tower for several years.

At 3:41pm on Tuesday, they welcomed their third egg this week. Experts think Belle could deliver one more egg in the next 48 hours.

It normally takes about four weeks for the eggs to hatch.

The public can watch the birds live via a color television monitor inside the Washington Mutual's Tower Financial Center at 1201 3rd Avenue in downtown Seattle.

Washington Mutual is offering a free $500 checking account to the person who most closely guesses the time and date of the first egg hatching. The winner will also get to view the nest up-close from the building's 55th floor penthouse. Contestants can enter their guesses at the Tower Financial Center beginning March 31st. Entries can be received until April 21.

Take a peek below at the Falcons courtesy the Falcon Research Group