In a large pot, render the bacon till crispy, add celery and onion, sauté till soft, add rosemary to release flavor then add wine, reduce by 1/4, add clam base, clam juice, reduce by 1/4. Add clams, cream, and milk. While the chowder is returning to a simmer, make a roux out of the butter and flour (in a medium sized pot), then take your celery and onion and 2 cups of water and place in the blender. Mix on high for 1 minute. Transfer to the chowder pot and mix well, add potatoes and continue to cook for 10 minutes stirring so you don’t burn the bottom. Ladle in the hot chowder to the pot with the roux, continue to ladle and stir using roughly 1/2 the chowder liquid. Return to the main chowder pot and incorporate the roux till blended in smooth. Adjust seasoning and refrigerate.