How do I use this formula to install Therion?
If I use brew install thereon I get 

mycaves:~ daveclucas$ brew install therion
Error: No available formula for therion 
Searching taps...
homebrew/science/therion

I don’t know where to go from there.

there is now therion homebrew formula created by one of the therion users so it should be much easier to install therion on Mac - https://github.com/Homebrew/homebrew-science/blob/master/therion.rb

Dave Clucas
daveclucas.com
sarawak-caves.com
dave.clucas@icloud.com

Exploring the World - One cave at a time