Radio & Television
News ran a two-part article on the state of the art of computers in the late
1950s (this is part 1). It had only been since ENIAC's (Electronic Numerical Integrator
And Computer) debut in 1946 at Massachusetts Institute of Technology (MIT) that
the public (or science community for that matter) was getting used to regularly
hearing about computers in the news. By 1957 there were many companies popping up
with electronic computer offerings. Originally the exclusive purview of university
research labs and defense installations, the size and cost of computers was moving
into the realm of affordability by corporations that used them for accounting and
bookkeeping, and in some cases even rented idle time to outside users. Desktop PCs
and notebook computers were still the realm of crazy dreamers.
Behind the Giant Brains
By Frank Leary
Part 1. Historical development and principles of electronic computers. Here's
the story about the devices that are now beginning to shape our lives. To be concluded
The IBM 650 magnetic drum data processing machine built tor commercial
use. This machine is designed to meet the ac-counting and computing needs in areas
between those now served by the company's very large and its smaller machines.
On a raw afternoon in February, 1946, officials of the Federal government and
the University of Pennsylvania, several luminaries of the world of science, and
representatives of the press met at the Moore School of Electrical Engineering,
on the University of Pennsylvania campus in Philadelphia.
Norbert Wiener, the MIT math professor who was to start a whole cross-section
of America using the term cybernetics, arrived characteristically without an overcoat.
Others parked their wraps and were shown into a large room at the back of the building.
Racks of electronic apparatus surrounded them. They were told they were inside an
electronic calculator which could solve complex differential equations - such as
an equation in external ballistics - faster than most people could state the problem.
Some were excited, others politely interested, a few were bored. They watched the
electronic gadgetry being put through its paces: punched cards with problem data
were fed in, cards with answers were punched seconds later. Someone checked the
results; they were correct. The press asked some questions, got some answers, and
then everybody went to dinner.
These men had been summoned to witness the first public showing of the Moore
School's electronic numerical integrator and calculator (a mouthful of description
shortened by Army Ordnance officers into the acronym ENIAC). It was not an occasion
that seemed particularly world-shaking, but the outgrowths from this machine have
been giving the world its share of shudders ever since.
The whole pattern of our existence being shaped by electronic computers, or "giant
brains," to use Edmund . Berkeley's much abused term. These computers can not only
solve complex problems in advanced mathematics, but models now in existence can
handle all kinds of information, from a payroll to the Bible. One, the Remington
Rand "Univac," a lineal descendant of the ENIAC, was recently used by the Thomas
J. Nelson Publishing Company to compile the Concordance for the Revised Standard
Version of the Holy Bible. Other systems are gradually infiltrating our daily lives:
our social security accounts, our insurance policy information, our income tax records,
all are being converted onto files of magnetic tapes, which can be swiftly and efficiently
processed by these automatic electronic computers.
The Monster on the Second Floor
All computing and processing of information in the Harvard Mark
I was performed by means of high-speed relays. This is what the calculator looks
like today, after some modifications have been made.
The reactions of people associated with them are as varied as opinions about
the proper proportions for a martini. Some people - notably the designers - feel
that these computers are the greatest boon to mankind since the invention of the
round wheel. Others, seeing phantoms of technological displacement, redeployment,
and unemployment, regard the introduction of electronic brains into everyday affairs
with great distaste. More considered opinions place atomic energy and automatic
computers on the same level, as the two most important technological advances to
have come out of the War.
In the New York office of one of the major manufacturers of the giant electronic
computers, a system has been set up to operate as a computing service bureau on
the second floor of the building. One of the old-line employees of this corporation
refers consistently to the machine as "the monster on the second floor." No amount
of persuasion, exhortation, or scientific evidence can convince him that it is anything
but a monster.
ENIAC, the first of all these electronic "monsters" - no more monster than the
thermostat that turns your heat on and off - has been working around the clock at
Aberdeen Proving Grounds ever since it was moved there in 1948. Another of the computer
industry's grandparents sits where it was first built, at Harvard. This is the famous
Aiken Relay Calculator Mark I, first of all truly automatic computers, built in
1944 by Harvard Computation Laboratories for the U. S. Navy. The two of them, different
in concept but complementary to each other, have sired many progeny.
Mark I was not electronic; ENIAC was. Mark I was automatically sequenced, which
is to say, it was capable of automatically performing a series of instructions fed
to it from punched paper tape; ENIAC recognized patterns of instructions set up
in advance on wiring panels. Modern computers, which are generally both electronic
and automatically sequenced, are logically descended from both "old" designs.
Mark I and ENIAC were both "war babies." Army Ordnance, trying to supply complete
ballistic data on new weapons to Army field commanders, had pricked up its ears
when John W. Mauchly, then an assistant professor on the staff of the Moore School,
and now an executive of Remington Rand's "Univac" division, had suggested an electronic
calculator as a possible solution; Ordnance funds sponsored the construction of
ENIAC. Mark I, designed by Harvard's Howard Aiken and built by his staff in cooperation
with International Business Machines Corporation, was fostered by the similar needs
of Navy Ordnance.
From these original wartime projects have sprung the burgeoning family of electronic
digital computers - computers which recognize and electronically process actual
numbers, or alphabetic characters, and not varying voltage levels, or turns of a
cogwheel or gear or axle. The latter, called analogue computers, form a completely
different family, with a somewhat similar heritage, but with different parents,
and different uses.
The Tributary Currents
The ENIAC as it looked when it was installed at the Moore School
of the University of Pennsylvania. The hundreds of cables, carrying control and
information signals from one part of the computer to another, all had to be set
up before a problem was run. Newer computers are somewhat more sophisticated, can
vary operations through a stored program of instructions.
Several separate streams have joined to form the torrent of activity that the
computer industry has become.
The principal headwater is an old and familiar one: man has always sought ways
of harnessing nature to serve him. Mathematicians are no exception, and creative
mathematicians especially have frequently bridled at the plain stickwork involved
in the rigorous proofs of their theories. Pascal, Leibnitz, Gauss, and Maxwell are
among the great scientists who designed and built mechanical aids to calculation.
These machines were of some help to their creators, but of little general use.
Another stream first was struck by a watchmaker named Jacques de Vaucanson, who,
in 1741, invented a delicate automatic loom for weaving figured silks. The designs
in the silks were established by patterns of holes punched in a metal drum; the
holes controlled the raising and lowering of the treadles. In 1804, Joseph Marie
Jacquard adapted the idea to a much larger scale for weaving tapestries, rugs, and
other heavier materials. To increase the utility of his automatic loom, Jacquard
used as controls punched sheets of stiff paper which could be changed fairly easily.
Within eight years, eleven thousand Jacquard looms had been placed in operation
The name of Charles Babbage, one of the two men in history ever to hold the Lucasian
professorship of mathematics at Oxford University, is a revered one in the computer
field, for Babbage was the first to envisage a truly general-purpose computer. He
also merged the de Vaucanson-Jacquard idea, of storing information as punched holes
in a sheet of paper, with the idea of mechanical computation.
Babbage began work on what he called a difference engine in 1823. The purpose
of the engine was to provide mechanical assistance for advanced mathematical computations.
The British government offered some financial support to his project, and he was
able to draw up working diagrams and specifications. But this was the era of Watt's
steam engine, when the criterion for the fit of a piston within the cylinder wall
was that a thin sixpence could just be slipped between the two; built to such tolerances,
Babbage's difference engine, and his later analytical engine, could never be made
to produce reliable answers. Eventually the government withdrew support, and the
Babbage designs became historical curiosities. Many of today's mechanical and electronic
calculators, however, possess a logical organization remarkably similar to the analytical
engine which was the triumph and despair of Babbage's life.
Enter the Census Bureau
The accumulator of Charles Babbage's difference engine, from
an old woodcut.
Mechanical tabulators, capable of simultaneously registering horizontal and vertical
sums, were the next important development. These grew, quite naturally, out of the
needs for statistical analysis, and many of the most important advances were made
in the U. S. Bureau of the Census. For example, Charles Seaton, who was Chief Clerk
of the Census Bureau, invented such a mechanical tabulator in 1872. And in 1887,
Dr. Herman Hollerith, then chief of Census' tabulation section, further adapted
the Jacquard punched-paper control system to the accumulation of statistical data.
This was a most important stride in mechanical computation, for it introduced into
a working system the concept of mechanically stored (remembered) information, which
could be used for many calculations or tabulations without the necessity for re-entering
the data from a keyboard. The Hollerith equipment was one of the ancestors of familiar
During the eleventh decennial census (1890), another member of the Census Bureau
staff, James Powers, developed another kind of mechanical tabulator which also used
punched cards. The Hollerith holes were rectangular; the Powers holes were round.
Both types of equipment were used by Census for years - are still in use, in fact.
Both men left the Census Bureau to merchandise their ideas in the commercial world.
Descended from the Powers' idea are the familiar Remington Rand and Underwood-Samas
round-hole cards, while Hollerith's idea
is found in the equipment of International
Business Machines, Compagnie des Machines Bull, and others.
Just prior to Hollerith's and Powers' inventions, a host of mechanical "arithmetic
engines," which we would today call adding machines, were patented. One of the most
important of these was the 1885 adding machine of William Seward Burroughs, probably
the first to be designed for production in quantity. These machines were the ancestors
of the modern desk calculator, now emerging, complete with high-speed electronic
and magnetic components, as a serious contender for the attention of the computing
For years following the invention of the various kinds of punched-card tabulators
and calculators - until about the time of World War II - these ma-chines were the
highest order of mechanical aids to computation. But the third major contributory
stream actually had appeared as early as December, 1919, when a paper describing
an electronic "trigger circuit" that could be used for counting pulses of electrical
energy was published in the first volume of Radio Review. The authors of the paper
were W. H. Eccles and F. W. Jordan; the Eccles-Jordan trigger circuit, and its many
modifications - multivibrators, one-shot trigger pairs, and so forth - all of which
are familiar to the world of television and radar, are foundation blocks of the
electronic digital computer as we know it.
While punched-card calculators were growing larger and more complex, a small
group of scientific minds saw the coming of an era when mechanical devices, however
fast, efficient, and succinct, would not be capable of keeping pace with the need
for information. All over the country, the capacity of punched-card calculator centers
was exceeded and expanded and exceeded again. In the late thirties, men in widely
separated activities began asking "can we apply electronics to this problem?" And
more and more frequently, the answer was "yes."
The Analogue Computers
Punched paper tape. such as that which is shown in the photo
in use in the famous Bell Relay Calculator, was the source of Harvard Mark I's instructions
A group of scientists and engineers, sparked by the physicist Vannevar Bush,
had meanwhile been pursuing another tack. During the twenties, Bush had merged an
idea of Lord Kelvin's, some of Babbage's concepts, and the then-recent development
of mechanical torque amplifiers. From this merger, he developed a reliable mechanical
device for the rapid and automatic analysis of differential equations. Several of
these differential analyzers were built from his plans at various universities in
this country and Europe. They were not digital calculators as envisaged by Babbage
and as built by the various punched-card manufacturers. They formed a major group
within the completely different class of analogue computers.
Analogue computers derive their name from the fact that they compute by mechanical
or electrical analogy. The turning of a gear, or a set of gears, through part or
all of a revolution may be used to represent, by analogy, a parameter in an equation.
Or the movement of a diagonal slide in a rectangular frame may represent another
parameter. Various torque converters or torque amplifiers perform operations analogous
to mathematical computations.
A simple analogue computer could be made from two circular gears in the ratio
of 3.1416 to 1. Turning the larger gear would cause the smaller to be displaced
3.1416 times as much. If angular displacements were shown on a pair of calibrated
dials, one could multiply by pi (approximately) on this simple device. Numerical
values for a diameter could be entered on the larger dial, and instantaneous approximate
values for the circumference would be read on the dial for the smaller gear. (Such
a device would, of necessity, produce approximations, since pi cannot be exactly
represented by a ratio of integers.)
Similarly, a large variable resistor might be wound on a card shaped like a sine
curve, instead of being wound on the usual rectangular card. The angle of displacement
of the wiper arm would then be a parameter in the equation; the voltage applied
across the resistor would be multiplied by the sine of this angle when tapped by
the wiper. Another wiper 90° displaced from the first would simultaneously produce
a voltage analogous to the cosine of the same angle.
Complexes of such mechanical and electrical analogies could be assembled into
computing systems which represented the equations of external ballistics, for example.
Such analogue computers were much used during the second World War for artillery
fire-control, in conjunction with radar tracking systems. Bell Laboratories, Sperry,
Westinghouse, and General Electric, among others, all built analogue computers for
the Army and Navy. More recently, such systems have been used in industry for a.c.
network analysis, for the analysis and synthesis of gas distribution systems, and
in many instances for the simulation of fairly complex machinery or systems (such
as missile systems or ultra-thin high-speed propeller blades) prior to their design
and construction. Because they work so readily with physical measuring and instrumentation
apparatus, and with mechanical or electronic controls, they are also natural choices
for the needs of industrial automation.
Herman Hollerith's electric counting machine as used in the 1890
census. The accumulated and tabulated results were presented on the counter dials,
and had to be copied off by hand.
Analogue computers are eminently suited for representing involved equations in
physical form. In design work, they permit the varying of parameters by analogy,
to determine the effect of such variations on the system as a whole. As control
systems for industrial automation, they can adjust valves, speed up or slow down
transfer systems, and so forth, as required by the standards of the output product
Analogue computers possess two inherent limitations. First, they cannot easily
be used for dissimilar problems. The computer itself is a mechanical or electrical
analogy to an equation; changing the equation means changing the hardware of the
computer. Second, they are generally only precise to two or three significant figures,
depending on the fineness of construction; and their accuracy depends, not only
on the accuracy of the input data, but also on the instruments which present the
answers (calibrated oscilloscopes, meters, counters, etc.) , and on the subjective
"feel" of the operator who inspects these presentations.
A digital computer can process ordinary numbers or alphabetic characters without
any trouble at all. It can handle continuously variable data only by "digitalizing"
it - sampling the value of the continuous function at regular time intervals and
giving it a numerical representation - and then applying the methods of numerical
analysis; but it can generally do far more types of work than an analogue computer,
and, once the information is translated into discrete digital form, it never loses
a decimal point of precision. Furthermore, the accuracy of the digital computer's
work can easily be checked by inverse operations (proving addition by subtraction,
etc.), by identical parallel operations compared for identical answers, or by many
General-purpose digital computing systems are far simpler than analogue networks
(although some of them are much larger); they can basically only add, compare, and
discriminate between relative magnitudes, store (or remember, if you prefer) information,
and shift the information around. Mostly they subtract by inverse addition, multiply
by repeated addition, and divide by alternately performing repeated additions and
subtractions. Depending on their discriminatory abilities, they can select paths
of action, or sort information, or start (or stop) a process. They can, in other
words, be empowered to make decisions.
Note well: be empowered to make decisions. The two most mystifying things, to
many people outside the field, are that these machines seem to make decisions, and
seem to remember information. Neither one is at all mysterious.
How Machines Remember
The first die-set punch, developed by Powers for the census of
1910. The operator set up on the keyboard all the values to be punched; she then
used the knee-treadle to gang-punch the card.
Memory, for example, as a machine function, is quite familiar to everyone. A
thermostat remembers two things: you tell it how hot you want it to be by setting
the value on a dial (which at the same time sets a control contact), and a bimetallic
thermometer tells it how hot it actually is. When the thermometer tells it that
the temperature has fallen below your setting, it turns on the heat.
A wall switch remembers that you turned it on, but the little button on a flashlight,
which must be locked to remain on, does not; as soon as you release it, it "forgets"
it was on and goes out. An annoying characteristic of certain cathode-ray tube phosphors,
for television purposes, is persistence; this is nothing more than the phosphor's
"remembering" the current which excited it into phosphorescence, and continuing
to glow after the current is gone. The characteristic was used to advantage in a
type of computer memory.
A magnetic tape or wire, or an acetate or vinyl disc, remembers the information
put on it for a long time. Materials which are truly elastic cannot remember; they
snap back into their normal state too readily. Brittle materials (such as glass
after its elasticity has been exceeded) are crude memories only, because they cannot
be restored. The most concentrated effort in developing memory systems has been
expended on hysteretic materials - materials which exhibit a time-lag between the
removal of a stimulus and the restoration of the material to its normal state. Magnetic
materials are an ideal example; after the magnetizing current is removed, a certain
amount of magnetism remains in the material (for a period of time depending on the
material). And much of the most fruitful effort in designing and building computer
memories has been devoted to magnetics research.
How Machines Make Decisions
The way the thermostat "decides" to turn on the heat is an excellent illustration
of the type of decision-making common in the computing machine. When the actual
temperature sensed by the thermometer falls below the setting of the contact, the
heat comes on. Now the thermostat setting is an artificially established control
point, set by a human operator; the control contact is moved closer to or farther
from the contact on the bi-metallic thermometer as the operator decides the temperature
should be higher or lower. The ability to reach a decision to turn heat on or off
is built into the thermostat, in that electrical power connects through the two
contacts to start a blower motor or automatic stoker.
A computer, which can compare quantities and discriminate between them, can choose
one of several paths of action in terms of the relative magnitudes of the two quantities.
The ability to select the alternate routes is built into the computer; the criteria
for the selection are given to it by the controlling human agency. The giant brain
and the simple thermostat both have the same degree of mindless unawareness of what
they are doing.
In making its decisions, the computer merely transfers control when one quantity
equals another, exceeds another, becomes less than another, or goes through zero.
If control is transferred to an instruction which tells it to "add," it adds; "stop,"
it stops; "rewind tape," it rewinds tape, and so forth.
A set of values can be given to the computer, and its comparison circuits can
check each one of the set, making several "yes-no" choices which lead to a compound
conclusion. In making these choices, the computer actually seems to be exhibiting
a complex type of judgment, but each single decision remains a "yes" or "no" choice.
The computer's secret is that it handles the most complicated problem in the world
in the simplest and most primitive steps. It is exactly like an expert player of
"Twenty Questions," who can narrow down on a single object out of all the objects
in the world by getting twenty "yes-or-no" answers.
It is an error to romanticize, humanize, or personify these devices. They are
completely unimaginative servants; they can do exactly what they are told, provided
a tube doesn't burn out, and provided also that what they are told is consistent
with what they can do; but they can do no more. They are controlled by the men who
make them, the men who operate them, and the men who program them. They are especially
at the mercy of the men who turn them off when the day is through.
Any time a computer seems to show imagination, it is because someone used imagination
in designing its program. If a "giant brain" solves a problem, it is because someone
(a) knew exactly how to go about solving that problem, and (b) knew precisely how
to instruct the equipment in the procedures for solving that problem. If anyone
ever gets one of these computers to write a symphony, for example, it will be because
that person knows the laws of melody and harmony, counterpoint, orchestral placement,
musical structure, and scoring, and knows what limits to set, and knows further
how to translate all these laws, maxims, and principles into an abecedarian lingo
that the simpleminded "brain" can follow. Anyone who can do that could write the
symphony himself, in less time than it would take to get the computer to do it.
The only advantage would be that the computer could turn out an infinitude of remarkably
similar symphonies at an extremely rapid rate.
(Behind the Giant Brains Part 2 to be concluded next month)
Posted June 26, 2019
(updated from original post on 7/16/2013)