postalmuseumblog.si.edu

D1Nar TIL in the 1910s there were cases of people using the postal service to mail their children across long distances because postage was cheaper than a train ticket
e04X4 TIL: The Hope Diamond was mailed through the United States Postal Service costing only $2 and $150 to insure.
b9BJ4 TIL that U.S. Postal Service regulations originally stated that mail deliveries be made "as frequently as the public convenience may require". Residential customers received mail two or three times a day until 1950 and some businesses received mail up to five times a day.