one of the many things we take for granted in the twentieth century is the speedy collection and delivery of letters to and from all parts of the world at astonishingly cheap rates. a husband away –1– a business trip can write home to his wife two thousand miles away knowing that the letter will reach her in a few days. his special air-letter may cost him less than a loaf of bread or his own bus fare to work. this service, however, is a blessing of comparatively recent –2–. until modern times the cost of sending letters privately was so great that the arrival of a letter was a considerable –3– and might even cost financial hardship to the receiver who had to bear the charges. there were, indeed, from the middle ages onwards, special messengers who –4– state correspondence, and other messengers employed to go and return with news between the great monasteries or the great merchants