Both of these are recent inventions that look obvious in retrospect and took a very long time to arrive, and both do something more specific than they appear to. Here…
A balloon is a very thin sheet of stretched rubber holding back a pressure it can barely contain - and almost everything it does follows from that. Here are twelve.…
Everything difficult about a watch comes from being small, portable and attached to somebody. The timekeeping principles are the same as a clock; the conditions are entirely different. Here are…
The shaft is not holding the canopy up. A sliding collar pushes struts outward, those push the ribs out, and the fabric between them is stretched tight - which is…
There is a useful question to ask about any everyday object: what did people do before it, and did they think they had a problem?
For most tools the answer…
Two facts explain most of this: freezing requires a starting point, and water vapour can turn directly to ice without becoming liquid first. Here are twelve consequences.
1. Freezing Needs…