Re: James. Clerk. Maxwell.
Einstein credited Maxwell. Maxwell was a hairsbreadth from relativity theory.
real father of Radio (though Hertz important). Marconi didn't claim to be a scientist, but an entrepreneur. His main jump was realising that radio range needed and aerial (wire) and an earth(ed connection) rather than a small loop. Later when VHF was possible, loops were used on transmitters. A multiturn loop does work for receive.
Also Maxwell realised how colour photography could be done (though a panchromatic film was some time in the future).
Many other things too.