Yup, He couldn't talk about almost anything he was ever involved in, but I heard years later that he had one too many of my father's drinks, (used to mix about 3x average, ha) and talked about traveling to another country, as a business man, and would report back what type of aircraft he would see at airport, that kind of thing, in Arlington now, he held some interesting posts over his life and had a 50 military person or so team in horse drawn wagon at his funeral. It was something.
Anyway, i don't think some of the old geo formulas for traveling through rock, ect, has changed since the 1800's, so try to keep an open mind.