During a Physics lesson, Pigeon once described to use a mistake in a text book in the school library, which consisted of a diagram with light travelling through it, but coming out at the wrong angle. He then stated that the librarian had two options:
1. To throw the book away.
2. To tear out the page.
However, S.P. And D.E. noticed that there were many other options that could have been considered. These were written over a period of many science lessons, mainly Physics, and there are now more than 200 options. These are all included here (originally included in the Appendix of the print version).