[USMA:30503] Old "Familiar" units

[Bill Hooper]

I just ran across an unimportant but interesting example of how poorly 
Americans understand the old "familiar" units that they think they 
understand. It was on a souvenir certificate for playing a calliope on 
a river boat. It stated that the person named on the certificate was 
qualified to play any steam calliope with pressures up to:

"90 lbs. P.S.I." !
Since the acronym P.S.I. stands for "pounds per square inch", the 
addition of "lbs." is clearly redundant and clearly shows that the 
author didn't have the foggiest idea what he/she was talking about. 
(Well, maybe he/she thought the "P" in "P.S.I." stood for "per".)

Regards,
Bill Hooper
Fernadina Beach, Florida, USA
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 Go Metric America! Or get left behind!
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^