Two materials are held apart in a state where one wants to give up electrons and the other wants to take them, and the separation is the entire trick. Here…
Source: Wikipedia
There is a particular kind of near-miss in the history of technology, where somebody builds the thing and does not realise what they have built.
Sound recording has an…
Combustion is a push. Everything in an engine exists to convert a series of pushes into smooth rotation, at speed, repeatedly, while managing the heat and friction that produces. Here…
There is a category of engineering problem that only becomes visible once you think about what a machine has to do over a whole journey rather than at any moment.…
There is a category of change so complete that the previous state becomes difficult to imagine, and street lighting is among the largest.
The state it replaced was real darkness.…
There is a useful exercise in considering how recently an ordinary thing became ordinary, and fire on demand is the most striking example available.
Fire itself is extremely old. Reliable…