Charles Babbage: a man beyond his time

Steps in automatic computing

The need for automatic computing was felt since the first years of the XVII century and several times in the course of history its principles were picked out. The most known application of these needs is the Blaise Pascal's Pascaline. This famous philosopher around 1642, when he was nineteen, invented a machine, based upon the automatic carry, to help his father, a tax-collector, in additions and subtractions. The size of that machine was 36x13x9, a little bulky but it was entirely mechanical. The attempts in the construction of such a machine were devoted to relieve the calculating toils and, more than anything else, to avoid computing errors. It was necessary the evolution of the needs of society and the increased scientific knowledge to see some real application. In fact, the thriving of these attempts wasn't casual, but it was a consequence of the born of positivism and the begin of the use of machines in the manufacture.

A step forward

The structure of the analitic machine includes all the essential elements of actual computers: the arithmetic-logic unit (mill), the memory (store), units for input and output (even a device for graph plotting) and there was a control mechanism for the flow of punch cards with the possibility of conditional jumps. It was a real general purpose calculator. The original machine would have executed 66 additions in a minute (a frequency of more than 1 Hertz) and had a memory of 200 accumulators of 25 whells each. The laws that it had to fulfill were:

• Every movement must be such that the machine breaks, stops or executes the task.
• No movement must depend on a spring.
• Operations must be executed in the least time possible.

A step backward

Unfortunately the Babbage's analitic machine was never realized because the mechanic technology of the period, that built complex and useful machines, wasn't able to produce the structures needed for such an ambitious project and, above all, the society didn't feel the necessity of automatic computing yet. Only some pieces were built and now you can see them at London in South Kensington museum. In our century, the World War II was an event that incited improvements in science and technology. In particular, the automatic computing was revived, for example, by the necessity of ballistic tables. Therefore, large teams of scientists had to solve problems that Charles Babbage had already solved alone one hundred years before.

We can read in Babbage's autobiography, Passages from the Life of a Philosopher (1864), that he wanted to build the analitic machine because he was convinced that the scientific knowledge coincides with quantification and he had an absolute faith in measurements and in the search for constants in natural phenomena. He wrote that when the analitic machine is built, it will guide the future progress of science. Now the analitic machine exists, it is closed in a box under your desk and you name it computer.

A short walk

	In the next Issue Science History will be Simulator of Galactic Collisions: 25th Anniversary.