"_The Radio Boys on Secret Service Duty_," "_The Radio Boys with the Revenue Guards_," "_The Radio Boys' Search for the Inca's Treasure_," "_The Radio Boys Rescue the Lost Alaska Expedition_." The development of radio telephony is still in its infancy at this time of writing in 1922. And yet it has made strides that were undreamed of in 1918. Experiments made in that year in Germany, and by the Italian Government in the Adriatic, enabled the human voice to be projected by radio some hundreds of miles. Today the broadcasting stations, from which nightly concerts are sent far and wide across the land, have tremendous range.…
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