Open 11 cans of clams. (Save 12th can for blending with thickening ingredients.) Separate clams into a bowl and pour clam juice into a large cooking pot.
Add potatoes and onions to clam juice. Cover and simmer until potatoes are tender. From this point on, always cook in an uncovered pot over low or medium heat. NEVER allow the chowder to boil!
Add clams, worcestershire sauce and optional bacon.
In a blender, mix very thoroughly 2 cups of milk, 12th can of clams and its juice, flour, cream, horse radish, and eggs.
Slowly stir the blended mixture into the cooking clams. Add the remaining 2 cups of milk. Turn heat down to low.
Cook for 10-15 minutes; stir occasionally, but do NOT allow the contents to come to a boil.
Dissolve the baking soda in one teaspoon of water and add it to the chowder to prevent ingredient separation.
Taste and season if necessary.
Float the stick of butter or margarine on the chowder. When it melts, fold it in.
Allow the chowder to ripen for at least 3 hours before serving