In this matter of guns, as well as in numbers of men, the Federals had enormous advantage. They had arsenals and foundries equipped with the most improved machinery to supply them, and they could draw freely upon the armouries of Europe, besides. The Confederates had no such resources. The few and small shops within their command were antiquated in their equipment and very sharply limited in their capacity. But they did their best. As soon as regular siege operations began, the Federals set to work establishing mortar batteries at every available point. Mortars are very short guns fired at a high “elevation”; that is, pointing upward at an angle of forty-five degrees to the horizon, or more than that, so as to throw shells high in air and let them fall perpendicularly upon an enemy’s works, breaking down defences and reaching points in rear of works to which ordinary cannon fire cannot penetrate. The lines were so close together—at one point only fifty yards apart—that everything had to be done under cover of some kind, and thus mortars became a vitally necessary arm with which to break down the enemy’s cover. The Confederates had none of these guns at first, but their foundries were at least capable of manufacturing so simple a weapon in a rude but effective fashion, making the mortars of iron instead of brass, and mounting them in oaken blocks heavily banded with wrought iron. In a very brief time the mortars began to arrive, and their numbers rapidly increased, but there were very few of the officers who knew how to handle a weapon so wholly different from ordinary guns both in construction and in methods of use. This scarcity of mortar-skilled officers in the lower grades gave Owen Kilgariff his opportunity. The thought occurred to him suddenly on the day after his vigil, and he acted upon it at once. He wrote to Arthur Brent, addressing his letter to Wyanoke, whence it would of course be forwarded should Doctor Brent be at Petersburg still. I want you, Arthur [he wrote], to use your influence in my behalf in a matter that touches me closely. For several reasons I want to be ordered from this place to Petersburg. For one thing, there is a matter of business, vitally interesting to you and me and closely involving the welfare of others. I simply must see you concerning it without delay. If I can get to Petersburg, I can see you, for Wyanoke is near enough to the beleaguered city for you to visit me in the trenches. There are other reasons, but the necessity of seeing you is the most important and the least personal to myself, so I need not bother you now with the other considerations that move me to desire this change, which you can bring about if you will—and I am sure you will.