My name is Albert Walker. I am seventy-eight years old, and I have spent most of my adult life building things designed to hold under pressure.

Water heaters. Roof frames. Engine mounts. Kitchen floors. A bridge once, early in my career, that I still drive over when I visit my sister in Murfreesboro because I want to see it holding. The satisfaction of that has not diminished in forty years. A structure bears weight or it does not, and you know the difference long before anything fails.