The US postal service was clearly keen on utilising film for purposes of either publicising its service or informing and/or instructing its intended audience in the early years of the 20th century. They made a whole range of films, each highlighting one particular aspect of their service. This one shows a couple of guys shoving envelopes into pigeon-holes at breakneck speed. You can't help thinking they were just placing envelopes into any hole they felt like and that, were the camera not on them, they would be working at one-tenth the pace shown on screen. One envelope falls from its slot and lies on the desk, ignored by the postal clerk, as if he is afraid that to acknowledge it would mean acknowledging an imperfection in the system...