NIMROD

It's 1951...
and the Festival of Britain opens its doors.

One of the many venues of the Festival — which extends across much of Britain — is the Exhibition of Science in South Kensington.

Here, amongst other wonders, you will see the Ferranti NIMROD.
This is the first digital computer designed specifically to play a game — truly the very first "Computer Game"... In the process, it illuminates principles of binary arithmetic and digital logic.

So, leave Lara Croft and her friends behind for a while, and journey back to the years BT (Before Transistors), where just to see a computer is an adventure, and to actually control it is the ultimate thrill!

Welcome to... NIMROD!

More than fifty years ago, on the 5th of May 1951, the NIMROD computer made its public bow. To celebrate that anniversary, a simulation of the original machine has been written. It seemed only fitting that this should run under the most modern Operating system available [grin], so it is built (only!) for HAIKU/BeOS. More information on the simulation, and the downloadable archive, can be found here.

The NIMROD was designed exclusively to play the game of 'NIM'. This is a simple game, where you start with a number of piles of tokens — traditionally matches. Each player in turn takes one or more tokens from any one pile, and the game continues until the last token is taken from the last remaining pile.

The simplest way of playing the game is when the winner is the one who takes the last item. There is also a 'Reverse' game, where the loser in the one forced to take the last token. NIMROD could play either version of the game. (It could also play a couple of other variants, which are not included in the simulation.)

The interesting thing about NIM is that there is a non-obvious strategy that will ensure a win, once it can be applied. Once one player is able to make a 'safe' move, the other cannot and must leave it 'unsafe', so that the first can again make it 'safe' next time. Furthermore, the strategy involves viewing the numbers of tokens as binary numbers, which makes it perfect for a computer algorithm. There is much more on this in the documentation that accompanies the simulation (or through the 'transcript' link below).

You can learn more about the various parts of the machine shown in the picture above by clicking on them. Or, if your browser doesn't support this, use one of the links below.

Left-hand Panel — Centre Panel — Right-hand Panel
Valve Bays
      Control Desk
    Booklet — Control Panel

Some more Facts and Figures on the hardware.

A booklet was available at the time that described the machine and its workings in detail. If you're interested, you can view a (long!) transcript.

The Australian Connection — a reminiscence by the (then) Ferranti engineer who came up with the idea for NIMROD.

"It's absolutely terrifying!" says Paul Jennings, a columnist at the time, as he relates his encounter with Nimrod. [ 215KB MP3, 55 sec. From a BBC recording, reproduced under the Fair Use provisions of Copyright.]

After the Festival of Britain closed, in October 1951, the Ferranti NIMROD was exhibited in Germany for three weeks. You can find an article on that (in German!) here.
Here's an attempted translation of the article.

A few years BC ("Before Computers") in 1940, at the New York World's fair, there was another NIM player — the electromechanical "Nimatron" (mentioned in the above article).

In its May 1951 issue, Discovery magazine featured an article on science at the Festival, which included this painting of NIMROD.

Colossus Returns! — back in action at Bletchley Park after more than sixty years. Somewhat predating NIMROD (!) this was arguably the very first digital computer,and as of November 2007 a replica is running once again. See the BBC article for more. (I took this photo a few years ago, while it was still under construction.)

There are a few more photos of 'Station X' (Bletchley Park) and its gadgets here.

• Download NIMROD Simulation package... (for BeOS and HAIKU only)

You will find extensive information about the Festival of Britain itself here

Follow this link to learn more about the Exhibition of Science.

The MusicWeaver and other BeOS software by Pete Goodeve

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Or contact the author: pete.goodeve@computer.org