Particles.

[Talanum46]

Particles created in the air are visible: look at a white or blue background and focus 50 mm from your eyes. I see them and they aren't points but have finite area. I can trace them onto paths approx. 10 to 40 mm long. Don't try to follow an individual one but look at the swarm. My mother said she had seen it too.

Edited September 25 by Talanum46

[Talanum46]

They seem to disappear, but not emit a flash of light.