Family of Secrets -> Oil depletion allowance -> Quartz -> Piezoelectricity -> Ultrasound -> Lazzaro Spallanzani -> List of Catholic clergy scientists -> Lorenzo Albacete -> Catholic University of America -> Charles Coughlin

Thanks for the rabbit hole! I now know more about a whole deal of subjects, starting with a political theme, gliding over taxation of natural resources, physical phenomena, priest scientists, history of how we found out that bats don’t fly by sight, finding out that there were priest scientists in my lifetime, the information that there is an catholic university in the US and landing on the wiki page of a antisemitic radio priest during the time of WW2 that reached around 30 million americans during his prime (funnily enough tying back into the radio grade quartz that is a valid resource for the Oil depletion allowance).

Edit: I haven’t even looked into your 2nd link yet.