Pine Valley is famous among bridge engineers. The first prestressed concrete bridge in the U.S., built using a particular kind of cantilever technology, it appeared to defy gravity during construction. It is located near two earthquake faults.

You recently mentioned a cockroach insecticide called “Chinese chalk.” However, you didn’t mention what was in it that makes it so toxic that it was banned. I have used this stuff and it works great. …

We later drove up Mount Helix and paced around the cross in the mountaintop park, staring all around, and every few minutes one of us would offer a reason why Eric couldn’t possibly die.

Dear Matthew Alice: This has been bugging me ever since I started stirring hot beverages with a spoon, especially coffee. When I add sugar to my hot coffee and begin stirring it, my spoon taps …