David Looser wrote:

Leafing through my copy of "The Practical Telephone
Handbook" (1912 edition) - as one does - I came across the
description of a transmitter for "Wireless Telephony". It
consists of an alternator that generates 5A at 60V at the
carrier frequency (60kHz) coupled to the aerial via a
tuned step-up transformer. The "modulator" is a
water-cooled carbon microphone connected in the earthy
lead of the transformer secondary. The best bit, though,
is that the alternator is driven by a steam turbine. I'd
always heard of "steam radio", I hadn't realised it
actually existed!

A turbine doesn't count. It's got to be a coal-fired piston
engine with a funnel and a whistle.

Ian