how can we measure time accurately by counting the footsteps of one's own shadow?

Question

an old techniqe of calculating time

Answer 1

You can only approximate it. For it to be accurate, you must take exactly the same sized steps at exactly the same rate all the time and know how long in time it takes for a step. Why count the shadow ? Count your steps. That way you don't need the sun out and you won't walk into a wall because you're looking at the ground. I think a clock or a wrist watch work much better.