A tape measure comes with several markings that some may not know, like the black diamonds. Here's what those symbols mean ...

A Timescale is a scale used to represent periods of time ... Lay out the rope next to the tape measure. Mark the beginning (today) ~20 cm from the end. Then mark the end of each Era. Color the Eras ...

If you have ever used a tape measure, you may have noticed a little hole or slot on the end of it. We'll tell you what that ...