While on the subject of U.S. Postal Service history, I should point out that the above photograph comes from the Smithsonian with the following eye-popping caption:

“After parcel post service was introduced in 1913, at least two children were sent by the service (with stamps attached to their clothing; the children rode with railway and city carriers to their destination). The Postmaster General quickly issued a regulation forbidding the sending of children in the mail after hearing of those examples.”