The quality of his nerve (as well as his foolhardiness) is shown by the fact that he once carried a dress-suit case full of the explosive around the city, jumping on and off street cars, and dodging vehicles.

When the proper moment came and the dynamite had been placed in an uncompleted building on Twenty-second Street, Guthrie gave the signal and the police arrested the dynamiters--all of them, including Guthrie, who was placed with the rest in a cell in the Tombs and continued to report to the district attorney all the information which he thus secured from his unsuspecting associates.
Indeed, it was hard to convince the authorities that Guthrie was a spy and not a mere accomplice who had turned State's evidence, a distinction of far-reaching legal significance so far as his evidence was concerned.
The final episode in the drama was the unearthing by the police of Hoboken of the secret cache of the dynamiters, containing a large quantity of the explosive.

Guthrie's instructions as to how they should find it read like a page from Poe's "Gold Bug." You had to go at night to a place where a lonely road crossed the Erie Railroad tracks in the Hackensack meadows, and mark the spot where the shadow of a telegraph pole (cast by an arc light) fell on a stone wall.

This you must climb and walk so many paces north, turn and go so many feet west, and then north again.

You then came to a white stone, from which you laid your course through more latitude and longitude until you were right over the spot.