Put the parsley, garlic, bay leaves, lemons, wine, oil and broth in a large pot and bring to a simmer. Season the liquid with salt and pepper. In the meantime prepare the artichokes.
Wash artichokes under cold water. Using a heavy stainless steel knife, cut off the stems close to the base. Pull off the lower petals that are small and tough. Cut off the top inch of the artichoke and rub with half a lemon to preserve the green color. Alternatively, you may put the artichokes in acidulated water. If you wish, trim the thorny tips of the petals with kitchen shears.
Place the artichokes in the steaming liquid, bottom up. Cover and simmer for about 30 minutes. The artichokes are done when a knife is inserted into the base and there is no resistance.
To eat, pull off a leaf and scrape the meat off the tender end with your front teeth. Dip the ends of the leaves in lemon juice and melted butter if desired. When you reach the center cone of purple prickly leaves, remove it. This is the choke that protects the heart. Now, scrape away the thistle fuzz covering the artichoke heart. The heart is the meatiest part of the artichoke. Steamed artichokes may be served hot or cold.