I said that such had been my own opinion when I first saw him, for he was the very ideal of a magnificent Southern gentleman, but that I had afterwards learned that though he was a spy and secret agent, it was on the Union side, and that he was high in the confidence of our officers, adding that I had seen the same man in our camp again, but had not spoken to him after the first occasion.

"Well," continued Mitchel, "he was, and is, a spy, and has been of great service to us. But I sometimes fear that we may have trusted him a little too far. Our boys are now in Georgia with him."

I sprang up from my seat. This was startling news. It had, indeed, been asserted by the camp-fires—where all events are discussed, and where conjectures too often pass for facts—that the missing men had turned spies, but I had scouted the idea. I thought that at most they might have been sent on ahead of us a short distance, to seize some important post in connection with similar details from other regiments, and supported by cavalry. But we were a hundred and fifty miles from the nearest point of the Georgian State line.

I looked at my companion in astonishment, and exclaimed, "What on earth are they doing in Georgia?"

"Andrews has taken them there," he said, "disguised as Southern citizens, with the intention of capturing a railroad train. He has also engaged a Southern man, who is an engineer on the same railroad, to run their locomotive, and when they get their train they will start for our line and burn every bridge they pass over. They will cut all the telegraph wires, and thus leave the enemy in helpless rage behind them."

My imagination took fire at the picture his few words had sketched. A train surprised by a handful of bold men in the heart of the enemy's territory; the passengers and train hands forced to get out under threat of instant death, and possibly a desperate fight before this was accomplished; then the wires cut, so that no lightning message could be flashed ahead; the secret confederate—whom there might be a show of compelling by force to mount the engine—set to his work; the train rushing on its way through a hostile country, past the towns and camps of the enemy, but rendered secure by the two elements of surprise and speed; the great bridges (like those at Green and Stone Rivers and other places, which had cost us weary delays and hard work in repairing),—all these bursting into flames as they were passed, and possibly other damage done before the daring adventurers returned in triumph to our own lines. I knew enough of war to understand, at a glance, the great military importance of thus severing railroad communications, for had I not seen our whole division brought to a halt, and General Mitchel rendered almost furious with impatience over a single burnt bridge? Besides, it required no particular insight to reveal the immense moral effect upon an enemy of such a bold stroke far in the centre of his territory. It would tend to diffuse distrust and fear through all the rebel armies if they were thus made to feel that no place in their whole country was safe from the presence and the blows of a daring adversary.

"Well, what do you think of it?" said Mitchel, as he saw my preoccupation.

"Why, it is the grandest thing I ever heard of!" was my enthusiastic reply. "I wish I was with them. But do you think that spy can be trusted? Spies are all the time betraying the confidence of one party or the other, and if he should be false to us, he has the lives of our boys in his hands. I have heard that he has been over the lines several times, and if he has been a secret rebel all the while, it would be a nice stroke of business for him to lead down a party of our best men and deliver them to the rebels."

"I have no fear of the fidelity of Andrews," said Mitchel. "He has been too well proved. But I am not so sure that he will be able to carry through all that he has undertaken, or that our boys can preserve their disguise until they reach the right point and are ready for the blow. If they should be detected while pretending to be rebels, it is not at all unlikely that they will be treated as spies and hung up. I wish they were back in camp again. But if they get through all right and burn the bridges, we will make for Chattanooga as fast as our legs can carry us. This is one of the reasons that makes the general so anxious to have that bridge done. If we should hear to-morrow, as we may at any moment, that those Southern bridges are smashed, it would be a race for Chattanooga with all the odds in our favor. But you must not breathe a word of this to one of the soldiers, or especially write of it to the papers, or to any of the relatives of the poor fellows, till they are back with us,—if they ever come back! Give me your candid opinion, was it right to let them take such a risk?"

Without the slightest hesitation I declared that it was right, giving the reasons that seemed most weighty. War is full of risks. In an obscure skirmish, or by a chance shot from the picket-line, the most valuable life may be put out. Now, if by a little additional risk a few men can do the work of thousands,—the work that if done in the ordinary mode would certainly cost a score times as many lives as are imperilled,—the risk is worth taking. Of course, it would not be right to send men on such an enterprise without their consent, but in the Union army it was never necessary to force men into any dangerous enterprise. Volunteers were always plenty enough.