Select rind from a firm, not overripe melon, and, before weighing, trim off green skin and pink flesh. Cut in inch cubes and soak for 1 ½ hours in the limewater.
Drain, cover with fresh water, cook for 1 ½ hours, or until tender, adding more water as it boils off. Let stand overnight in this same water and next morning drain.
Bring to a boil the vinegar, 1 pint water, sugar and spices tied loosely in cheesecloth. Add the drained watermelon and boil gently for 2 hours or until the syrup is fairly thick.
Remove the spice bag, pack the watermelon pickles and syrup in sterilized glass jars, seal airtight, and store in a cool place.