astily toward the train and scrambled up the steps. The conductor waved his signal to the engine-driver and swung aboard. The locomotive bell began to ring, there was a hissing of steam, and a puf

their ears, their hearts beating with high determination to give all that they had of

hrough a region entirely unknown to them. But so busy was each boy with his thoughts that he hardly noticed what at other times would h

set to roving about, trying to pick out suspicious characters, or detect suspicious acts? And what would New York be like? What was there about this gre

level of the streets, that was filled with many tracks and closed in with enormous walls of cement. Then the train ran into a great shed

Captain Hardy led them to a corner of the waiting-room that offered a little privacy, and there they s

ss outfits. They are probably of small sending power and operate in unusual wave lengths. It is almost impossible for our regular service to detect them. In fact I don't know how we are ever going to locate them unless we organize the amateurs all over the country so that they can listen in and catch practically everything that goes through the air. We are not able to do that yet, but I shall be ver

f's instructions?" asked

detecting crime. So we shall work under the direction of the secret service and in

trol," said Roy, "why did you telegraph for just the four

next to impossible to watch all of it, and there are hundreds of thousands of Germans or people of German descent living here. The Radio Chief needs sharp eyes and ears as well as trained fingers just now, and he

le his mind went back to that first summer at Camp Brady, when he had been the most backward, self-distrustful, helpless lad in camp. Now he was chosen to serve his government, to do work of the greatest importance for his country

er of those sharp questions that showed very well why he should have been c

o back to your medical duties? We can work ever so much

Hardy might not be able to remain with them. Now ev

pies and the government could well afford to give up one ordinary doctor in order to get four skilled

hardly repress

ret service immediately. As I have told you, we must get acquainted with both. But before we do, I

ught sight of the great maps of the world high up on the walls. The crowds of people coming and going hardly seemed like crowds, so vast was the structure. With reluctant feet the four boys pushed on. But when they had mounted the steps to the arcade and caught sight of the illuminated transparencies showing sce

nds of people were hurrying along, passing in endless throngs up and down t

ed Roy. "Why does everybod

st; and if you boys want to make a reputation in New York you'll have to hustle some. But I don't want you to make that kind of a repu

ong the highway in slow-moving lines as far as the eye could see. Bells were ringing, whistles tooting, horns blowing, motor-cars honking, newsies shouting. The grinding of car-wheels, the rattle of ca

ghty easy to get lost here. The wireless patrol will have

rs found it difficult not to get lost. At every step something new and u

them how to cross the streets so as to avoid accidents. And ever he kept his eye on them to see that none of the four became separated from the gr

party. There, in a little eddy of sid

diagonal. Right here where Broadway, Thirty-fourth Street, and Sixth Avenue intersect, is one of the busiest corners in the city. Overhead are two elevated railway tracks. On the ground are six street-car tracks, crossing one another. Under the surface are two subway tracks. So you ha

New York drug store has a city directory. And in the back of the directory you will find a table that will show you approximately where to find the street number you want. Don't forget. If you are to do effective work, you must become so familiar with New York that you can find your

g buildings in sight. They had all heard of the Waldorf-Astoria Hotel and they gazed up Thirty-fourth Street a

blocks up Broadway. Now I want you boys to see everything you can as we go along, and to try to remember all that you see. Wherever you go you must remember that you are in New York to detect German spies and presumably to run down German wireless outfits. We don't know where they are. We may be looking at one this very instant. So keep your eyes open. If you see anything that rese

estrians. At Times Square they paused for a look at the great newspaper building that gives the place its name, and at the great hotel

on the firing-line in France,"

atform and the boys boarded it. A short ride an

edentials and introduced his companions, and four delighted boys found themselves blushingly shaking hands with New York's famous chief of

re full of it. And I recall that when I read the story I wished I had as acco

piness. But they were too much

he Commissioner, "what

direction of the secret service. But we have no

he ferries. Learn the city so that you can get around rapidly. Make the acquaintance of as many policemen, wireless operators, secret service men, and other persons as you can. Don't forget that a kind deed or a thoughtful act will help you to make friendships quicker than anything else; and make all the friends you can. In police work you never know who will be of assistance to you. And abov

should have some kind of passes that will enable them to get through the police lines. There may come time

or a moment. "If I were sure

rupted Captain Ha

well

a button on his desk. A

or Captain Hardy and these four

man or put you through any police line. Do not let any one know you have them and never use them unless you absol

," said Henry, "and carry the cards

resourceful," smil

h the cards and handed

would like to see our wireless department and get acq

ide them to the wireless room

ious 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 r

ave 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 Pat

idge, to see Chief Flynn. He was a large, heavy man, with black hair and eyes and a short mustache. He sh

bout you," he said. "Do you k

mitted thei

, 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.

Captain Hardy. "Go there," he directed. "A wireless ou

ures on it. "That," said he, "is my private telephone number. B

s party found itself in the r