Peel cucumbers, cut in two lengthwise, scrape out seeds with a silver spoon, salt and let stand over night. Drain and dry cucumbers. Make a syrup of the sugar and vinegar. Add the mustard seed and also the whole cinnamon and cloves tied in a bag. Boil cucumbers in this syrup only a few moments until they are glassy. They must remain crisp. Pack in jars and cover air-tight.