I lifted this interesting little exercise from Mob
01. Grab the nearest book
02. Open it to page 161
03. Find the fifth full sentence
04. Post the text along with these instructions
From Collapse: How Societies Choose To Fail Or Succeed. Since 161 had a picture, showing a map of Mayan sites in Mexico and Central America on it, I had to use page 162.
Making matters worse, most of the Yucatan Peninusla consists of karst, a porous sponge-like limestone terrain where rain runs straight into the ground and where little or no surface water remains available.
Rivetting, isn't it?