Hi, I am hoping one of you will be able to help me. I have a book,
"Box-Making Basics" and in it it has some "classical or traditional
proportions, these include the double cube, the root-of-two box, the
1:2:3 box, and the golden rectangle." (p.4)

I don't understand what the double cube is. In the picture it has 1 1
2 where the height is 1, the width is 1 and the length is 2. What does
this mean?

I really don't understand what any of them are. the double cube one
just looked the easiest to understand.

Thank you.