The clerk returned with the cards and handed them to Captain Hardy.
"Before you go," said the Commissioner, "perhaps you would like to see our wireless department and get acquainted with Sergeant Pearce who is in charge of it."
He summoned a patrolman to guide them to the wireless rooms and wished the boys success.
A few moments later Sergeant Pearce was showing them the apparatus. Two operators sat at a wonderful Marconi outfit with receivers clamped to their ears. In another room various instruments were installed here and there, the walls were covered with diagrams of wireless instruments and outfits, and lines of men were sitting at long tables with receivers at their ears. It was the police wireless school. High above the roof the aerial hung, suspended between the main dome and a smaller dome at one end of the building.
"We are going to equip every station-house with wireless," said Sergeant Pearce, "and the men you saw at work in the school are being trained for operators. We have put wireless outfits on some of the patrol-wagons and on the police boat Patrol, so you see we can get into touch instantly with any precinct or with the Patrol no matter in what part of the harbor she may be. And when you have as big a harbor as we have, with several hundred miles of waterfront, that means something."
From Police Headquarters the little party went directly to the Post Office Building, near the Brooklyn Bridge, to see Chief Flynn. He was a large, heavy man, with black hair and eyes and a short mustache. He shook hands with each of the party, and gave each a searching look. He spoke quietly but right to the point.
"I had word from Washington about you," he said. "Do you know anything about the city?"
The boys admitted their ignorance.
"Then your first job is to get acquainted with New York. Get some maps and guide-books. While you are getting your bearings you can establish a wireless watch. I have a number of outfits in different parts of the city. For the next week or two, while you are getting acquainted with the city, I want you to maintain a twenty-four-hour watch at a place I shall send you to. Divide the time among you so that some one is listening in all the time. Here are the call signals of all the legitimate plants you will hear, either on land or water. Pay particular attention to call signals. If you catch one not in this list, be sure to get every word sent and let me hear from you at once. We have other operators listening in for messages of the usual commercial wave lengths and for very long wave lengths, so you need watch only for messages of less than three hundred meters."
He wrote an address on a slip of paper and gave it to Captain Hardy. "Go there," he directed. "A wireless outfit has been installed and accommodations await you."