Language is failing Beryl Dusinbery. She is 99 years old and having trouble retrieving words. “One minute she has a word, then she hasn’t. Where does it go?” Conversely, Shimi Carmelli, 91, can’t forget.

The rules of shelving can seem arbitrary, even arcane, but the fundamentals are easy to learn: two hard covers, and no more than three paperbacks of the same title, on each shelf.  The exception is the face-out. If the jacket is displayed horizontally, behind it you can stack as many books as can fit.

Last summer, my husband had gone hiking with our two dogs when one of them — a year-old rescue who weighs in at over 50 pounds, can scale steep inclines like a mountain goat and has the speed and grace of an Olympic athlete — suddenly collapsed.