"In this position it is absolutely impossible for one to turn round, so narrow is the passage. At this point a difficulty that is not anticipated arrests many a visitor. Water rises through the stones that form the floor and contributes to reduce the height of the gallery. If one elects to continue, there is no choice but to take a bath that reaches to one's middle. At a distance of nearly 7 feet comes a right angle, and the passage goes on for 6 feet, then turns to the left by an obtuse angle and pursues its course for 12 feet, then again turns to the right by another obtuse angle, and for 15 feet more one is still half under water, till N is reached, after which the level of the floor rises, as does also the ceiling; one is able to stand erect alongside of another person. In face of one, the wall is cut perpendicularly and seems abruptly to close the passage. However, at a few inches above the soil is a little opening D, formed like the mouth of an oven, and giving indications of a space beyond. In diameter it is about 1 foot 6 inches; by crawling through this hole, an achievement difficult to accomplish, as one cannot even use the elbows to work one's way forward, the explorer descends into a semicircular hall P whose vault is arched and is supported by two oval pillars, 7 feet high. The hall is 24 feet deep and 18 feet wide at the entrance, and is rounded at the further extremity. The soil in this chamber is encumbered with stones and rubbish thrown in from an opening at R, which seems to communicate with other subterranean excavations." Nothing was found in these chambers and passages that could give an approximate date, but in the upper "abris" was some Gaulish pottery. The water that had half filled the lower passage is due to the river having been dammed up for a mill, and so having raised the level considerably. Originally the passage was certainly dry. Although this _souterrain réfuge_ is curious, yet it does not present some of the peculiarities noticeable in others--that is to say, elaborate preparations for defence, by contriving pitfalls for the enemy and means of assailing him in flank and rear. The usual artifice for protection was this. The entrance from without led by a gallery or vestibule to an inner doorway that opened into the actual refuge. The passage to this interior doorway was made to descend at a rapid incline, and as it descended it became lower, so that an enemy entering would probably advance at a run, and doubled, and would pitch head foremost into a well, from 20 to 30 feet deep, bottle- shaped, sunk in the floor immediately before the closed and barred door, and which was gaping to receive him. Such a well-mouth would usually have a plank crossing it, but in time of danger this plank would be removed. To make doubly sure of precipitating the assailant into it, a side-chamber was contrived with slots commanding the doorway, through which slots pikes, spears and swords could be thrust.