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 widespread mental model of a kite that treats the string as a leash, restraining something that would otherwise escape.
That model produces a specific prediction: cut the…
There is a category of discovery that arrives sideways, as the residue of an argument about something else entirely.
The argument concerned whether a space containing nothing could exist. The…
There is a category of living thing that is truly difficult to classify, and lichens are the standard example.
The difficulty is not that they are obscure. They are everywhere…