How Long Till Sundown?

Here is another neat trick. If you hold your hand out at arm’s length, the width of your fingers approximates to 15 minutes. You can use this to judge how long it is till sundown (and remember you have approx … Continued

‘Man is the Measure of All Things’ (Pythagoras) Some handy estimation tricks.

This astonishing Pre-Socratic was a brilliant mind. I guess everyone knows his ‘Theorem” about right angle triangles. The saying above might not be quite so well known (or his enjoiner, ‘Eschew beans’! I think I know why!), but we can … Continued