[js2]

I loved Devil in the White City so it's too bad to hear that you didn't find Thunderstruck very good.

Marconi was working on developing microwave transmission at the time of his death. Microwave antenna are small but are only good for line of sight transmission.

[AlbertCory]

I found I'm alarmingly ignorant of the development of radio.

People had household radios in the 20s. Marconi was still alive then. From this admittedly unscientific book, he seems to have been resolutely ignorant of other people's work in the field.