05/12/2021

014 – Automatic Séance Controlled Computer – 1944

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Don’t worry about people stealing your ideas.
If your ideas are any good, you’ll have to ram them down peoples throats.  Howard H Aiken

Howard H Aiken was a student at Harvard working his way to becoming a lecturer and professor.  His thesis was on the conductivity of vacuum tubes, investigating ‘space charge’ – an excess of electrical charge in valves.  His thesis embroiled him in routinely solving complex non-linear differential equations and he was unimpressed by the time-consuming calculators to hand.

1937 Aiken developed the idea for a calculator or computer for which he sought a manufacturer.  He also requested support from Harvard’s physics department, but the head asked why Aiken wanted to build something that already existed, and was seldom used, in the Physics Research Laboratory.

He was referring to Babbage’s set of calculating wheels that had been sent to Harvard at the time of its 250th anniversary.  These inspired Aiken to research Babbage’s earlier ideas.  He stated that ‘[It] felt that Babbage was addressing him personally from the past’.

Aiken’s first choice manufacturer was Monroe for a mechanical approach, but he was rejected.  His next target was RCA, for an electronic solution.  Only IBM showed interest, with an electromagnetic component approach.

The Harvard Mark 1, the Automatic Sequence Controlled Calculator, was initially delayed and then accelerated by WWII  It was meant to be collaborative but it ended up largely being built at and by IBM. 

When completed in May 1944 the Mark 1 was huge, weighing 5 tons (tonnes) with 760,000 parts and 530 miles (853km) of wiring.

Mark 1 had punched-tape inputs and was output by punched cards or a standard IBM electric typewriter.  It was slow – addition and subtraction took a machine revolution (1/3 second).  Multiplication twenty cycles (6 seconds) and division fifty-one cycles (15 seconds).

Mark 1 was run until 1959.  It worked on the mathematics of radar and anti-mine magnetic fields.  John von Neumann used it to calculate some implosions for the Manhattan Project.

Aiken launched the Mark 1 giving little credit to IBM.  As a result Thomas J Watson Sr had Wallace John Eckert of Columbia University define his own device, the IBM Selective Sequence Electronic Calculator, which was completed in January 1948.

Aiken went on to develop the Mark II which used relays, the Mark III with solid-state components and magnetic drums, and the Mark IV with selenium and germanium solid-state components.  Aiken was early in applying his equipment to data processing for business accounting and billing systems.

Aiken established a graduate program in computer science and the courses attracted many early pioneers in computing – An Wang, the word processor entrepreneur, engineers who designed the IBM System/360, Grace Hopper and others.

1947 the Harvard Mark II stopped working for no obvious reason.  Hopper and the team discovered a moth caught between the contacts of a relay and interrupting the connection.   The dead moth was sellotaped into the operations log, the entry saying very simply ‘First actual case of bug being found.’

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