There is a difference between materials that are gathered and materials that are extracted, and it explains why some textiles were cheap and others were not.
Wool is gathered. It…
Maya Linton
There is a question about corrosion that people rarely ask and that turns out to be the whole subject.
The question is not why metals corrode. Almost all of them…
There is a category of object where the useful part is the absence rather than the substance, and netting is the clearest example.
A net is mostly nothing. The material…
There is a small group of building materials that go round in a circle, and lime is the clearest.
The cycle is truly closed. A rock is heated to drive…
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…