In the past, “portable afloat” radio operations from small boats were advocated from this blog (https://thewakesileave.wordpress.com/2015/10/05/radio-amateur-portable-afloat/). Here is evidence of a much earlier pioneer.
A colleague radio-amateur recently forwarded the URL for the 2nd issue (June 1922) of “Popular Radio” (http://www.americanradiohistory.com/Archive-Popular-Radio/Popular-Radio-1922-06.pdf). One of the articles, entitled “How To Use Your Radio Set in Summer Time” by Pierre Boucheron (pp. 103-107), includes a picture of a 15-20 foot-long “launch” with four people on board.
The boat sports an antenna making use of two vertical poles (abt. 15-16 Ft.) with 5-6-foot long horizontal poles held at their top. According to the legend on the picture this set-up was reportedly used in the summer of 1921 to report from the water on the “International yacht race for the Royal St. Lawrence Club trophy” (the Royal St. Lawrence Yacht Club is based in Montreal, QC).
There is not enough detail in the picture to assess the actual features of the antenna. However it is fair to assume that some wires (likely more than one, possibly four) must have been strung across the horizontal poles held by the 15-20 Ft poles attached to the bow and stern of the “launch” and held in place by the six shrouds visible on the picture. This, and the fact that this is a nautical set-up, suggest that the antenna might have been a Marconi “T” antenna with a design similar to those that at the period the Marconi Company was deploying in larger ships (https://en.wikipedia.org/wiki/T-antenna): the antenna would have comprised one or more vertical wires reaching up towards the horizontal ones strung across the horizontal poles. In fact, it was customary at the time to split the vertical wire in several cables each connecting in a “T” junction with each of the horizontal cables at the top, as seen on the drawing for the add of the “ABC Unit” advertised in the first issue of “Popular Radio” (http://www.americanradiohistory.com/Archive-Popular-Radio/Popular-Radio-1922-05.pdf):
Perhaps it was similar to the antenna fitted in 1914 to the rescue launch of SS Aquitania (http://www.americanradiohistory.com/Archive-Popular-Radio/Popular-Radio-1925-01.pdf):
No reference is made as to the wavelength at which this antenna would have resonated or the transceiver that may have been used for the occasion (ship wireless at that time used wavelengths of 600 and 300 meters: 0.5 and 1 MHz). All it is said is that “the set was operated on a current produced by a hand-driven generator”. The same picture was later reused in other article: http://www.americanradiohistory.com/Archive-Popular-Radio/Popular-Radio-1925-03.pdf, see p. 214. In this occasion it included the following legend:
“THE FIRST “RADIOREPORTER” TO COVER A YACHT RACE. When the Royal St. Lawrence Yacht Club held a contest four years ago, an ingenious sport writer rigged up a radio transmitting apparatus on a small launch and sent out “sideline” reports of the race by means of electric power derived from a hand-driven generator.”
Hence, although we do not know the identity of this pioneer, at least we can safely consider that it occurred almost one hundred years ago and that it happened in Canada.
Here is the complete collection of “Popular Radio” (1922-1928) online: http://www.americanradiohistory.com/Popular_Radio__Master_Page.htm.