Bring the potatoes and clam juice to a boil, and cook potatoes until tender. Set aside. In a separate pot, sauté onions, celery, and bacon until onions are translucent. Add clams and sauté for about five minutes.
Add the butter and allow to melt. Add the flour and cook until slightly brown. Stir in clam juice and potatoes. Bring to boil to thicken. Add parsley and half and half.
Cook on medium for 30 minutes. Serve with bread!