A military dictionary

by William Duane

These galleries have been out of use for some years. The miner gets at the body of the place which is attacked, either through a subterraneous gallery that is dug beneath the ditch, when the nature of the ground will permit the attempt, or under cover of the epaulement, which covers the passage of the ditch. When the ditch is full of water, and the miner has made considerable progress under it, he instantly makes the best of his way to the breach, either by swimming, or by supporting his body on a raft of timber; as soon as he has reached the spot, he works into the earth among the ruins of the wall, and completes the object of his enterprize.

Galeries de communication, Fr. are subterraneous galleries, by means of which, the garrison of a besieged town or place may, without being perceived by the enemy, communicate from the body of the place, or from the counterscarp, with the different outworks.

Galeries souterraines des anciens, Fr. Subterraneous galleries as originally invented by the ancients. The author of the Dictionnaire Militaire in his last edition of that work enters upon the explanation of these galleries by the following curious assertion.

“I must, he observes, in this place, assert with the chevalier Folard, that it would be absurd to deny the superiority which the ancients possessed over us in the essential knowlege and requisites of war, and that they pushed the different branches of that science to as high a pitch of perfection as it was possible to raise it.

“The only inventions which the moderns can boast of, are those of fire-arms, mines, and furnaces. But then, on the other hand, we stand indebted to them for our lines of circumvallation and of contravallation, our approaches or trenches which are effected from a camp to its different batteries, together with the construction of those batteries; our parallel entrenchments or places of arms, the descent into, or the filling up of the ditch, our covered saps in mining, and our open galleries; we owe to them, in fact, the original art of throwing up works and of creating obstacles, by which we are enabled to secure ourselves, or by various stratagems to annoy our enemies. The ancients were indeed superior to us, in the means of defence.

“The origin of subterraneous galleries or passages in mining, is totally unknown to us; a circumstance which proves their antiquity. We read in the History of Josephus, that the Jews frequently made use of them; so that neither the Greeks nor the Romans, who, in many instances arrogate to themselves the exclusive glory of invention, were the authors of this discovery.

“The method which was pursued by the ancients in their passages of mines, resembled the one that is invariably followed by the moderns. But the latter possess a considerable advantage over the former, in this sort of attack and defence, which advantage consists wholly in the invention of gunpowder.

“The ancients, it is well known, could only undermine in one way; namely under the terraces or cavaliers, or under the towers and battering-testudo-machines (tortues bélieres,) and in order to do any execution, they were obliged, in the first place, to construct a spacious high subterraneous chamber, to carry away and raise the earth, to support the remainder by powerful props, and afterwards to fill the several chambers with dry wood and other combustible materials, which were set fire to in order to reduce the towers and various machines that were placed above, into one common heap of ruins. But this attempt did not always succeed; for owing to the magnitude of the undertaking and the time it required, the enemy might either trace the miners, cut off their communication with the main body of the place, or get into the chambers before they could be finished, or be properly prepared for inflammation.

“The ancients constructed their galleries on a larger scale than we adopt. They were wider, but less elevated; whereas those that we use require less trouble; our chamber mines being more contracted, and having an advantage of access by means of the different branches. One or two small chambers are sufficient with us to blow up the whole face of a bastion. But the ancients only sapped in proportion to the extent of wall which they were determined to demolish. This was a tedious operation; for when the besieger had reached the foot of the wall, it became necessary to run a gallery along the whole extent of what he proposed to demolish. Subsequent to this, he had to operate upon the entire front, during which the besieged found time and opportunities to open subterraneous passages, and to discover those which the assailants were practising against them. In the latter, indeed they seldom failed.

“The Romans were extremely partial to subterraneous galleries. By means of these secret passages they took Fidenæ, and Veiæ; and Darius, king of Persia, by the same method took Chalcedon. That species of gallery which is run out under the soil of an encampment, and pushed forward into the very body of a town, has been known from time immemorial. The Gauls were likewise very expert in their management of subterraneous galleries. Cæsar mentions the use of them in five or six places of his Commentaries.”