Be careful.

Look out for Kline, he is the sharpest man in the United States secret service." For a brief instant longer, Jimmie Dale stood under the street lamp, his mind in a lightning-quick way cataloguing every point in her letter, viewing every point from a myriad angles, constructing, devising, mapping out a plan to dove-tail into them--and then Jimmie Dale swung on a downtown bus.

There was neither time nor occasion to go home now--that marvellous little kit of burglar's tools that peeped from their tiny pockets in that curious leather undervest, and that reposed now in the safe in his den, would be useless to him to-night; besides, in the breast pocket of his coat, neatly folded, was a black silk mask, and, relics of his role of Larry the Bat, an automatic revolver, an electric flashlight, a steel jimmy, and a bunch of skeleton keys, were distributed among the other pockets of his smart tweed suit.
Jimmie Dale changed from the bus to the subway, leaving behind him, strewn over many blocks, the tiny and minute fragments into which he had torn her letter; at Astor Place he left the subway, walked to Broadway, turned uptown for a block to Eighth Street, then along Eighth Street almost to Sixth Avenue--and stopped.
A rather shabby shop, a pitiful sort of a place, displaying in its window a heterogeneous conglomeration of cheap odds and ends, ink bottles, candy, pencils, cigarettes, pens, toys, writing pads, marbles, and a multitude of other small wares, confronted him.

Within, a little, old, sweet-faced, gray-haired woman stood behind the counter, pottering over the rearrangement of some articles on the shelves.
"My word!" said Jimmie Dale softly to himself.

"You wouldn't believe it, would you! And I've always wondered how these little stores managed to make both ends meet.