It's nice that the explanation starts with this disclaimer: > Keep in mind that these determinations are approximate as there is some discrepancy at different

It's nice that the explanation starts with this disclaimer: > Keep in mind that these determinations are approximate as there is some discrepancy at different latitudes and in different seasons. But it doesn't explain that this only works on the northern hemisphere, and in summer only if you're well above the tropics. Near the equator, this isn't going to work at all, and on the southern hemisphere, everything needs to be reversed. It's a cool trick, but I think just understanding the relationship between the earth and the sun is easier and more universally applicable.