Mark IV, Newest Computer, Opens This May

Mark IV, the latest and most advanced of Harvard's calculators, will probably be completed about mid-May, Howard H. Aiken, director of the Computation Laboratory, reported this week. Aiken also explained that the lab's activities now include the fields of economics, bible reading, optics, and the analysis of jet engines.

Mark IV is expected to be about 250 times faster than its prototype, Mark I, and will cost from $300,000 to $400,000. Mark II and Mark III, the other mechanical brains, were also built at the Computation Lab next to the Graduate Center, but they are now at the Naval Proving Ground in Virginin.

Typical of the problems that were too complex for solution before the Marks arrived is Economics Professor Wassily W. Leontief's General Equilibrium Theory. Covering the alternatives possible from production, the theory in especially useful in the allocation of short materials. The advanced stages of this work are so complicated that Leontief must wait for the completion of Mark IV to proceed with his research.

His new analysis method, which graphically plots both an entire economy and its intricate interrelations, enables government and industry planners to gauge beforehand the effects of a shortage, a surplus, partial unemployment of the nation's economy, or a wage hike.

In the past, economists, unable to handle the huge masses of empirical data necessary for such projects, tended to oversimplify and to build "display cabinets without displays," comments Leontief. But the invention and development of the computer has lessened the reluctance to work problems which require heavy computation.

Simplest Theory

The simplest theory covering an economy of two involves 14 equations, and as the population goes up, the number of equations required increases in geometric fashion. With modern computers, socialist planners may be able to fill the function which producer and consumer handle in a free economy through millions of individual deals.

Leontief hesitates to use the word "predict" when he talks about the possible consequences of his work, but readily asserts that his figures should be able to "narrow down the range of economic possibilities until probabilities are pin-pointed."

He cautions that variables such as new inventions and changes in government policies are unpredictable and can effect the practical validity of Mark's computation.

One of the first projects to be handled by Mark IV will be to "read" copies of the Bible under the direction of the Reverend John W. Ellison of Tucson, Arizona. Ellison will spend two weeks supervising the "reading" of 100 ancient manuscripts of the Bible, two at a time. The machine will indicate where words have been added or deleted, as well as differences in spelling and word order.

Helping the Government

Government work of Mark I included an assignment for the Air Force when it was planning to construct a model of a jet engine with a takeoff unit incorporated in it. Mark I proved this development impractical and the Air Force cancelled their order for the model. According to Aiken, the money that Mark I saved the taxpayers would be sufficient to run the computer for two and one-half years.

In the field of optics the computer is giving added evidence of its versatility. Mark I is able to trace mathematically rays through aerial lenses while plans for the lenses are still on the drawing board. This frees the opticians from their tedious calculating duties and enables them to work exclusively on developing advanced optical designs.

While taking breathers between problems. Mark I has ground out 26 volumes of mathematical tables to be printed by the University Press.

The Operating Technique

When working out a problem on Mark I, the operator must first translate the information into mathematical terms. The resultant equations and instructions are then coded, punched out in a binary pattern of a paper tape and put in place on the machine.

A binary computing machine is one which uses a number system based on the number one instead of ten. In such a system, there are only two digits, one and zero. Hence the number system, instead of going one, two, three, four, etc., goes one, ten, 11, 100, 101, 110, 111, 1000, 1001, etc. Thus eight in a number system based on ten is the same as 1000 in a number system based on one.

A two digit, instead of ten digit, system is employed by computing machines in order to overcome the limitations of electric tubes, which can handle the two digit system much more easily.

After the preliminary work the actual solving is begun, when a button is pressed.

NORMAN B. BOLOMON is copying mathematical equations and symbols onto a magnetic tape on Mark IV's coding box." This tape will be fed into the computer where it will control its operations. The coding box measures about six feet by ten feet and has over 200 boys with a number or symbol on each. Mark IV is nearing completion and full use. Tests are now being conducted with the new machine. Multi-colored lights flash, a complex of gears spins, and soon an electric typewriter types the answers on a white spool of paper.

Because the machine turns out answers faster than the electric typewriter can print them, answers are first recorded on another tape which is channeled to a tape render. The answers are then relayed to the battery of four typewriters at a slower clip.

An elaborate system of checks throughout the process of calculation guards against inaccuracy. All numbers are recorded by two parallel and independent mechanisms. Unless both numbers on the answer tape are identical, the striking action of the type bar sets of an alarm and stops the typewriter.

While a problem is in process, it may be necessary to hold some results from the first part of a solution for use in a latter part of the solution, or to hold aside some of the data originally fed in for latter use. The machine is able to handle this type of memory work.

Imagination Is Lacking

But Aiken strongly asserts that the machine can do only what man commands. It lacks imagination.

Aiken scoffs at speculations that this "mechanical brain" will over approach the overall capabilities of the human brain, but believes that the computer will alleviate mental drudgery in the future, just as power-driven machinery relieved physical labors after the Industrial Revolution.

The magnetic tape principle can be adapted to operate a number of coupled machines in almost any industrial process. Thus it is possible theoretically for an article to pass through all its stages of manufacture in one continuous, uninterrupted operation.

A Question of Weather

For a number of years, weathermen have known that they could accurately predict the weather by compiling extensive data. However, by the time the computation had been completed, the weather had already arrived. Now with the calculators, this 24-hour delay may be reduced to a few minutes.

Insurance companies are interested in the storage capabilities of the machine. Since the binary dots can represent anything, including our alphabet, it should be possible to file immense amounts of information on the tape. The operator would simply dial a certain number and the desired data could be - transformed speedily from dots to typed English.