Making a tiny pinhole with the hands and looking through it results in a crisp image without the need for glasses, according to a video by MinutePhysics, a Montana-based YouTube channel.

Given their limitation of blocking peripheral vision, pinhole glasses are entirely unsuitable for use outside controlled environments, and should certainly never be worn whilst driving.

How to watch the eclipse without glasses For those without access to eclipse glasses, a pinhole projector is another way to safely view the eclipse.

If you're caught without your reading glasses, or you encounter some terrifically fine print on a box or contract, you have two options: curse your abnormal retina design, or pinch your fingers ...