
The Handheld Analog Computer That Made the Atomic Bomb 45
szczys writes: When the physicists and mathematicians of the Manhattan Project began their work they needed to establish which substance was most likely to sustain vigorous fission. This is not trivial math, and the solution of course is to use an advanced computer. If only they had one available. The best computer of the time was a targeting calculation machine that was out of service while being moved from one installation to another. The unlikely fill-in was a simple yet ingenious analog computer called the FERMIAC. When rolled along a piece of paper it calculated neutron collisions with simple markings — doing its small part to forever change the world without a battery, transistor, or tube.