Allan Pinkerton, The spy in the rebellion; being a true history of the spy system of the United States Army during the late rebellion, revealing many secrets of the war hitherto not made public, compiled from official reports prepared for President Lincoln , General McClellan and the Provost-Marshal-General .

Just at this moment I again received a warning from my supporters, and hastily jumping to the ground, we hid ourselves until the pedestrians had passed out of sight and hearing. When I resumed my station the Captain and Mrs. Greenhow were seated at a table in the rear part of the room, and their conversation was carried on in such low tones that, in consequence of the storm that was still raging, I could not catch but fragmentary sentences. At last, however, accustoming myself to the noise, I heard enough to convince me that this trusted officer was then and there engaged in betraying his country, and furnishing to his treasonably-inclined companion such information regarding the disposition of our troops as he possessed.

Presently, he took from an inner pocket of his coat a map which, as he held it up before the light, I imagined that I could identify as a plan of the fortifications in and around Washington, and which also designated a contemplated plan of attack.

My blood boiled with indignation as I witnessed this scene, and I longed to rush into the room and strangle the miscreant where he sat, but I dared not utter a word, and was compelled to stand by, with the rain pouring down upon me, and silently witness this traitorous proceeding.

After watching their movements for some time, during which they would frequently refer to the map before them, as though pointing out particular points