Who designed Analytical Engine, the first programmable computer?

The Analytical Engine was a general-purpose computer, which was a successor to Babbage’s difference engine. It featured a control flow, an arithmetic logic unit along with integrated memory. It was one of the most successful achievements of Charles Babbage. Let us take a look into how Charles Babbage managed to build the Analytical Engine and its influence today.

Charles Babbage

The idea of the computer first occurred to the British inventor Charles Babbage (picture, left) in about 1833. Others had made calculating machines before him. But Babbage was the first person to conceive of a machine that could be programmed to carry out different calculating operations, as a computer can. Babbage designed a machine called the Analytical Engine that had the basic feature of a modern computer. 

Analytical Engine

It was to be a mechanical computer, containing complex systems of shafts and gear wheels. However, only some parts of the Analytical Engine (see photo below) could be built. The engineering required to complete it was far beyond the techniques of the age, and Babbage died in 1871 without knowing whether his computer would work or not.

In fact, Babbage was far ahead of his time. The first computer a British wartime decoder called Colossus was not built until 1943. Like modern computers, it used electronics, as mechanical operations were too slow. Colossus and all other computers since are really the descendants of Babbage’s Analytical Engine.

Apart from the fact that Babbage had a great idea that could revolutionize the world, he was not able to build any of his designs due to inadequate funding and conflicts with his chief engineer. It was in 1941, when the world’s first general-purpose computer was built, more than a century after Babbage had introduced the idea of Analytical Engine in 1837. 

Design

Babbage’s first attempt was to create a mechanical computing device such as the Difference Engine, which would help solve trigonometric functions and tabulate logarithms by evaluating finite differences to come up with approximate polynomials. Babbage was never able to complete it due to conflicts with his chief engineer. As a result, the British government withdrew its funding from the project. 

Soon, Babbage realized that much more general design, the Analytical Engine was possible, which would use punched cars to carry out commands. Furthermore, three types of punch cards were used: one for numerical constants, one for arithmetical operations, and one for load and store operations. In addition to that, there would be three separate readers for the different types of punch cards. 

Construction

Later down the road, Babbage sought ways to simplify the machine even more. He also managed to assemble the parts before his death in 1871. Then, in 1878, a committee of the British Association for the Advancement of Science went on to describe the Analytical Engine as a marvel. Although the committee recognized its usefulness, but was not able to estimate the cost of building it. At the same time, it was unsure as to whether the machine would work after building it. 

Babbage considered his self-made Analytical Engine a universal calculating machine, which, if provided sufficient time, would solve any possible arithmetic calculation. This argument was based on three observations: First, arithmetic operations carried out on more than 40 digits can always be carried out by breaking them into 40-digit segments. Second, calculations can be specified by strings of operation and variable cards of an unlimited extent. Therefore, there is no limitation to either the complexity or size of programs. Third, numbers could be read by punching into number cards and reading back later. 

Babbage’s son Major General Henry Prevost Babbage continued with publicizing his father’s work. He spent an ample amount of time showering his interest in his father’s work as well. Furthermore, Henry and his older brother Dugald spent time in Babbage’s drawing office, learning workshop skills. 

Henry was eventually able to complete his manually operate machine for subtraction, addition, and multiplication. However, its reliability was the main issue. There was no doubt that Henry’s work was sound but without the inspiration and boldness of his father, Charles Babbage.