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It was possible for a program to have a bug that caused a printer to suck in
paper but not print, so sometimes dozens or hundreds of sheets of paper would
spew out of the top of the printer before it could be stopped.
When processing blank lines, the IBM 1403 could suck in paper at about 75
inches per second, so a program with a bug in its print routine could easily go
through more than 100 linear feet of paper before it was possible to shut it down.
I recall seeing blank paper moving through the IBM 1403 printer so fast that the
paper shot up three or four feet in the air.
The IBM 1403 printer also needed fairly serious maintenance that included oil-
ing the moving parts. As a result, the area underneath the printer had to have paper
towels or mats below it due to occasional oil leaks.
The IBM mainframe printer paper in those days was not individual sheets but
rather continuous forms with perforations. They were large sheets with 132 print
positions. The left and right edges had a separate perforated band with holes that
allowed sprockets to feed the paper through the printer. The printer paper was de-
livered in large boxes, and the paper was fed into the printer directly from the box
itself. These boxes of paper were heavy and were normally moved on wheeled
carts.
These printers were so fast and used so much paper that a tidy computer room
was not feasible. All of the IBM 1401 computer rooms had boxes of paper ready
to be loaded in front of the printers and empty boxes ready to collect outputs at the
rear of the printers.
Paper storage was a logistical problem of this era, and it was necessary to set
aside rooms just to hold paper and punch cards. These rooms needed air condition-
ing because moisture could expand the paper and cause mechanical problems with
printers and card readers.
Although I enjoyed my time as a programmer for the Public Health Service,
private industry was expanding in computers and software so rapidly that I decided
to look for other programming jobs outside of government.
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