Midnight
Here they came in contact with a group of plotters who were trying to put through a nefarious deal and were able to thwart the rascals through the use of radio . By that same beneficent science too they were able to save a life when other means of communication were blocked . And not the least satisfactory feature was the utter discomfiture they were able to visit upon Buck Looker and his gang . These and many other adventures are told in the fourth volume of the series , entitled : `` The Radio Boys at Mountain Pass ; Or , The Midnight Call for Assistance . '' And now to return to the radio boys as they stood facing the angry storekeeper amid a constantly growing throng of curious onlookers . They had been in many tighter fixes in their life but none that was more embarrassing . `` I 'll have them arrested ! ''