For most of the history of ocean navigation, a ship's crew could tell you how far north or south they were with reasonable confidence and had very little idea how…
The counterintuitive fact underlying all of this is that mixing two soft metals frequently produces something substantially harder than either, and the reason is geometric. Here are twelve.
1. Why…
Almost everybody has experienced this, and almost nobody has considered how strange it is.
Sitting still in a vehicle, entirely uninjured, having eaten nothing unusual, a person becomes progressively unwell…
The test is simple: pigment colour looks the same from every angle, and structural colour changes as you move. Once you know that, a great deal of the natural world…
Ask most people whether counting is natural and they will say obviously yes. Every culture counts. Children learn numbers early. It feels less like a skill than a faculty.
The…
Pitch depends on how fast something vibrates, and everything below is a different method of controlling that rate and then getting the vibration into the air loudly enough to hear.…