The encyclopedia · Engineering & Operations · Technical decision · 1957–1970
The Transorma let five operators sort 15,000 letters an hour
In 1957 the US Post Office installed the Transorma, a keyboard machine that routed letters into 300 chutes — doubling hand sorting speed.
Werkspoor · US Post Office Department
The solution
Sorting mail by hand could not keep up with 20th-century volume. On April 10, 1957, the Post Office Department installed the first semiautomatic sorting machine at the Blair Post Office in Silver Spring, Maryland — the Transorma, built by the Dutch company Werkspoor and distributed by Pitney Bowes.
Thirteen feet high, it had five operators at sorting keyboards. Each operator read an envelope's destination and keyed a sorting code; the letter was then carried by conveyor to a tray and deposited into one of 300 chutes, returning to the lower level neatly stacked.
At full operation the five operators sorted 15,000 letters an hour — double what the same crew managed by hand. The machine proved that mail processing could be mechanized at lower cost, even if humans still had to do the reading.
Why it worked
- One keying act replaced per-letter hand walking
- 300 chutes let one machine cover many destinations
- It doubled throughput with the same crew
- It proved mechanized sorting was worth the capital
What can be applied
When humans are the bottleneck, have them do the one thing machines can't — read the address — and automate everything after that keying.
Aftermath
The Transorma showed the limits of semi-automation — operators still read every address — and pointed the way to machines that read for themselves; today optical character readers sort nearly all US mail without human keying, and a public art installation marks the Blair site.
Sources
- Transorma Mail Sorting Machine sign (catalog record)
- Transorma Mail Sorting Machine sign (object page)
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