Melt the butter in a 5-qt Dutch oven and saute the onions, celery and bell pepper until they soften. Toss in the bacon, the drippings and the chopped oyssters and simmer gently over low heat, stirring constantly, until the oysters curl and a rich gray-colored base forms. Drop in the artichoke pulp and bottoms and blend them well into the mixture. Stir in the oyster liquor and the artichoke cooking stock. Bring it to a boil, but be sure to keep stirring or the oyster liquor will scorch and stick to the bottom of the pot. Boil for about 4 minutes. Stir in the basil, reduce the heat to simmer and let the bisque cook slowly for another 5 minutes. Stir in the cream, a half-pint at a time, and turn the fire back up to high! When the mixture comes back to a boil, reduce the heat again so that the bisque just barely "bubbles" and add the salt and pepper. Taste before adding the salt as the oysters contain a lot of salt. After 10 minutes, remove from the heat and allow it to "set up" for 15 minutes so that the flavors blend. Serve, garnished with parsley.