But, in spite of the great array of detective talent, no one could get a line on von Ewald.
In April, when Dick Walters returned from the Coast, the other men in the Service were frankly skeptical as to whether there was a von Ewald at all. They had come to look upon him as a myth, a bugaboo. They couldn't deny that there must be some guiding spirit to the Teutonic plots, but they rather favored the theory that several men, rather than one, were to blame.
Walters' instructions were just like the rest—to go to New York and stick on the job until the German conspirator was apprehended.
"Maybe it's one man, maybe there're half a dozen," the chief admitted, "but we've got to nail 'em. The very fact that they haven't started anything of consequence since the early part of the year would appear to point to renewed activity very shortly. It's up to you and the other men already in New York to prevent the success of any of these plots."
Walters listened patiently to all the dope that had been gathered and then figured, as had every new man, that it was up to him to do a little sleuthing of his own.
The headquarters of the German agents was supposed to be somewhere in Greenwich Village, on one of those half-grown alleys that always threatens to meet itself coming back. But more than a score of government operatives had combed that part of the town without securing a trace of anything tangible. On the average of once a night the phone at headquarters would ring and some one at the other end would send in a hurry call for help up in the Bronx or in Harlem or some other distant part of the city where he thought he had turned up a clue. The men on duty would leap into the machine that always waited at the curb and fracture every speed law ever made—only to find, when they arrived, that it was a false alarm.
Finally, after several weeks of that sort of thing, conditions commenced to get on Dick's nerves.
"I'm going to tackle this thing on my own," he announced. "Luck is going to play as much of a part in landing von Ewald as anything else—and luck never hunted with more than one man. Good-by! See you fellows later."
But it was a good many weeks—August, to be precise—before the men in the Federal Building had the opportunity of talking to Walters. He would report over the phone, of course, and drop down there every few days—but he'd only stay long enough to find out if there was any real news or any orders from Washington. Then he'd disappear uptown.
"Dick's sure got a grouch these days," was the comment that went around after Walters had paid one of his flying visits.