4 lbs. Steamer clams, soaked to remove sand
2 to 3 lbs. rockweed (or fresh spinach blended with 4 Tbs. salt)
4 1-1/2 Lb. live lobsters
8 ears of corn, shucked
1/2 lb. unsalted butter, melted
Pour 1 inch of water into a clam steamer or large kettle (about 20 qts.)
Divide the rockwood or spinach and salt in 4 equal parts. Place one quarter in the bottom of the steamer, and nestle the lobsters on top.
Cover the lobsters with another layer of rockwood, and position the corn on it. Cover the corn with a third layer of rockwood, and scatter the clams over it.
Cover the clams with the last of the rockwood. Bring the steamer to a boil over high heat, covered, and steam the "bake" for 30 to 45 minutes, or until the clam shells have opened wide.
Divide the lobster, clams and corn between 4 large platters, and serve with equal portions of butter. Discard the rockwood.