Heat water and salt to boiling in large kettle.
Plunge lobsters headfirst into water.
Cover; heat to boiling.
Reduce heat; simmer about 10 minutes.
Place lobster on its back.
With a sharp knife, cut lengthwise in half.
Remove the stomach, which is just back of the head, and the intestinal vein, which runs from the stomach to the tip of the tail.
Do not discard the green liver and coral roe.