I checked out Adrift: Seventy-six days lost at sea by Steven Callahan today and started reading it this evening.   I noticed something very interesting almost right away.  There were lots of penciled in checkboxes next to various lines in the text, and on the lines that were checked, a word or two was underlined in pencil.  In looking at these words, I guessed they were words that one of the previous library patrons who checked out the book didn’t know.   Here’s the list of words:

• don (as in "don a raincoat")
• shoal
• trawlers
• rogue
• trends
• nuances
• vivid
• evolved
• cohesive
• astrophysicist
• intuitive extrapolation
• enthralled
• exorbitant
• communion
• convoluted
• exhilarating
• helm
• crevice
• quay
• pandemonium
• autumn equinox
• lunatics
• capstan
• prone
• rancorous
• abated
• aft

After that, it appears they gave up.  Now, at first I thought maybe it was a child, but I’m not sure that’s the case since there were many fairly complex words that were not underlined (e.g. "perspective", "conclusions", "hydrodynamics").

For some reason, I found this all very interesting.