New York Times, April 17, 1909, page 1:
WIRELESS 'PHONES IN USE.
System Now Connects Portland and the Islands of Casco Bay.
Special to The New York Times.
PORTLAND, Me., April 16--The first commercial wireless telephone system in the world was thrown open to the general public here to-day. Four out of thirty stations which will connect Portland with the islands of Casco Bay are in commission.
The first message was one of congratulation from Mayor Clifford at Portland to A. Frederick Collins, the inventor of the system, who was at Cape Elizabeth, across the bay.
Heretofore telephone communication between Portland and the islands of Casco Bay has been impossible owing to the rocky bottom and swift tides.
Four wireless telephones were used at the same time and each received its designated message. A new tuning apparatus, invented by Mr. Collins, was used, and the inventor says he has solved the problem of selectivity, thus making the wireless telephone even more secret than the present wire telephone systems. Over 400 messages were sent the first day.