by
Mark Ollig
What’s
10 feet high, 3 feet wide, 100 feet in length, operates using approximately
70,000 resisters, 10,000 capacitors, 18,000 vacuum tubes, and miles of wire;
and weighs nearly 30 tons?
That’s
right, you guessed it: A computational device called an Electronic Numerical
Integrator And Computer, otherwise known as the ENIAC.
The
ENIAC has been acknowledged as the first fully-operating, all-electronic,
digital computing system.
Its
historical marker says the ENIAC “signaled the birth of the Information Age.”
This
computer was large and U-shaped. The 40 panel bays it was comprised of
inhabited a room 30 by 50 feet.
The
electricity required to operate the ENIAC was substantial. It used 150-174
kilowatts of power, which was fed directly into it via dedicated power lines.
ENIAC’s
design and construction was financed during World War II by the US Army.
In
July of 1943, under the secret code name “Project PX,” the building of the
ENIAC began in earnest at the University of Pennsylvania’s Moore School of
Electrical Engineering.
The
computer became fully operational in 1946.
John
Mauchly and J. (John) Presper Eckert Jr. were the co-inventors of the ENIAC.
They
both filed for a US patent June 24, 1947, and were later granted U.S. patent
number 3,120,606.
Mauchly
worked more on the side of the hardware and electrical components, such as
vacuum tube technologies. There were 10 different types of vacuum tubes used in
the ENIAC.
Eckert
engineered the project and solved many of its technical problems, including how
to get better dependability from the vacuum tubes by operating them at
one-quarter their normal power rating.
Arithmetic,
memory, and control elements were part of the ENIAC’s operating systems. There
were 20 processing registers or “accumulators” used for addition, subtraction,
multiplication, division, and square-root problem solving.
According
to Eckert, some of the sub-elements of the ENIAC were binary in nature.
During
the computer’s testing in 1945, it performed nuclear physics calculations used
during the building of the hydrogen bomb.
When
the computer was finished being built, it was transported to the Aberdeen
Proving Ground in Maryland. It provided “firing tables” for specific
trajectories needed to accurately reach intended targets.
At
the time, ballistic targeting calculations normally took 12 hours to perform
using a mechanical calculator. The ENIAC could perform these calculations in
just 30 seconds.
The
army also used its computing power for solutions to other ballistic equations,
and artillery firing control problems.
Other
uses for the ENAIC’s processing capabilities included: weather forecasting,
wind-tunnel designs, atomic-energy calculations, and other scientific
applications.
Information
was input into the computer using IBM punch cards, and the computer could
handle 125 cards per minute. The output information was punched onto IBM cards
and then printed.
The
ENIAC’s personal requirements called for six technicians working three 8-hour
shifts, seven days a week to maintain 24-hour a day operation.
Back
in the day, yours truly used many spools of rosin-core solder for soldering
“jumper wires” to metal terminal posts on the main distribution frame at the
telephone company; however, I doubt I did close to the 5 million hand-soldered
joints which were needed to connect all the electrical components and wiring
inside the ENIAC.
The
ENIAC’s programming interface consisted of controlling some 3,000 rotary
switches and dozens of cables plugged into sockets. You programmed the computer
by adjusting switches and physically plugging cross-connect cables into the
correct sockets in order to work the desired computations.
The
six original programmers of the ENIAC were: Betty Snyder Holberton, Jean
Jennings Bartik, Kathleen McNulty Mauchly Antonelli, Marlyn Wescoff Meltzer,
Ruth Lichterman Teitelbaum, and Frances Bilas Spence.
These
six pioneers created some of the basic concepts used in modern computer
programming.
The
existence of the ENIAC was publically announced Feb. 14, 1946; however, “None
of us girls were ever introduced . . .we were just programmers,” Antonelli said
in 2001.
Information
about these six programmers can be found here: http://eniacprogrammers.org.
“An
amazing machine, which applies electronic speeds for the first time to
mathematical tasks hitherto too difficult and cumbersome for solution,” said
The New York Times when writing about the ENIAC in 1946.
In
a 1995 Computerworld magazine interview of J. Presper Eckert by Alexander
Randall 5th, Eckert talked about how fast the ENIAC was in solving problems.
“A
person with a paper and pencil can add two 10-digit numbers in about 10
seconds. With a hand calculator, the time is down to 4 seconds. The ENIAC was
the first electronic digital computer and could add those two 10-digit numbers
in 0.0002 seconds – that’s 50,000 times faster than a human, 20,000 times
faster than a calculator,” Eckert explained.
The
computer processing life of the ENIAC ended at 11:45 p.m. Oct. 2, 1955, when it
was turned off.
Four
of the original 40 panels of the ENIAC are on display at the University of
Pennsylvania School of Engineering and Applied Sciences. You can read more
about the ENIAC at the website: http://tinyurl.com/bytes-eniac.
