In the previous chapters we have described four giant mechanical brains finished by the end of 1946: Massachusetts Institute of Technology’s Differential Analyzer No. 2, Harvard’s IBM Automatic Sequence-Controlled Calculator, Moore School of Electrical Engineering’s Electronic Numerical Integrator and Calculator (Eniac), and Bell Telephone Laboratories’ General-Purpose Relay Computer. All these brains have actually worked long enough to have demonstrated thoroughly some facts of great importance.
WHAT EXISTING MACHINES HAVE PROVED
The existing mechanical brains have proved that information can be automatically transferred between any two registers of a machine. No human being is needed to pick up a physical piece of information produced in one part of the machine, personally move it to another part of the machine, and there put it in again. We can think of a mechanical brain as something like a battery of desk calculators or punch-card machines all cabled together and communicating automatically.
The existing mechanical brains have also proved that flexible, automatic control over long sequences of operations is possible. We can lay out the whole routine to solve a problem, translate it into machine language, and put it into the machine. Then we press the “start” button; the machine starts whirring and prints out the answers as it obtains them. Mechanical brains have removed the limits on complexity of routine: the machine can carry out a complicated routine as easily as a simple one.
The existing giant brains have shown that a machine with hundreds of thousands of parts will work successfully. It will operate accurately, it will run unattended, and it will have remarkably few mechanical troubles.
These machines have shown that enormous speeds can be realized: 5000 additions a second is Eniac’s record. High speed is needed for many problems in science, government, and business. In fact, there are economic and statistical problems, now settled by armchair methods, for which high-speed mechanical brains may make it possible to compute answers rather than guess them.
Also, these machines have been shown to be reasonable in cost. The cost of each of the large calculators is in the neighborhood of $250,000 to $500,000. If we assume a ten-year life, which is conservative, the cost is about $3 to $6 an hour for 24-hour operation. Since each mechanical brain can, for problems for which it is suited, do the work of a hundred human computers, such a machine can save its cost half a dozen times. And these machines are only engineers’ models, built without the advantages of production-line assembly.
The cost of giant mechanical brains under design in 1947 and 1948 is in the neighborhood of $100,000 to $200,000. The main reason for the reduction from the previous cost is the use of cheaper automatic memory. As designs improve and charges for research and development are paid off, the cost should continue to go down.
NEW DEVICES FOR HANDLING INFORMATION
In the laboratories working on new mechanical and electronic brains, scientists are doing a lot of thinking about new devices for handling information. Research into devices for storing information shows that magnetic wire as used in sound recording is a rather good storage medium.