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 .

[399] arrangement, and expressed themselves in extravagant terms of thankfulness for a trip which, no doubt, would be exceedingly pleasant. The Captain then proceeded to explain to them the nature of the battery which was to be experimented with on the morrow. He explained the object to be obtained by this battery, which was to break up the blockading fleet at the mouth of the James River, and thus give the South an outlet to the sea.

The next day they started in a carriage for the scene of the exhibition, which was located about ten miles below the city. Arriving at the appointed spot, they found quite a large number of military men, many of them accompanied by ladies, assembled to witness the testing of the machine, from which so much was expected.

A large scow had been towed into the middle of the river, and the submarine vessel was to approach it and attach a magazine, containing nearly half a bushel of powder, to which was attached several deadly projectiles, and this was to be fired by a peculiarly constructed fuse, connected by a long wire coiled on board the submarine vessel.

At a given signal the boat was sunk into the river, about half a mile below the scow, and shortly afterwards it began to make its way under the water towards it. The only visible sign of its existence was a large float that rested on the surface of the water, and which was connected with the vessel