were so terrified with their repeated stumbles, that they could with difficulty be pulled along, and they trembled so violently as to be almost incapable of keeping their legs, for the surface frequently cracked and partially gave way in places which appeared to be secure, and the parties were so often obliged to alter their direction, that they almost despaired of being able to bring off their horses. After much winding and turning, this was, however, at length effected, and both horses and riders were heartily glad to find themselves once more on firm ground. Nothing was said to our guides of this accident, but it served to convince us that their apprehensions of the marsh were not groundless, and we afterwards took the precaution of dismounting when we had occasion to cross any part which was considered to be dangerous. We found on examination that many hollow spaces of considerable depth and extent existed in various parts of the marsh; and that the crust of salt and mud which covered them was sometimes no more than two inches, and an inch and a half, in thickness. These usually occurred in the most level parts, but as the crust was everywhere in appearance the same, there were no means of ascertaining where they existed, but by breaking the surface which concealed them. The water contained in these hollows was invariably salt, or very brackish; it was usually clear, and was in some places deep: the depth of mud below the water must also have been sometimes considerable, and the vacant space contained between the outer surface of the marsh and the water was in various instances observed to be as much as twelve and fifteen feet in depth. We had no means of ascertaining the depth of the water in the hollow alluded to above; but the space between its surface and that of the marsh appeared to be more than twelve feet, and, from the sound occasioned by the fall of the pieces into it, its depth could scarcely have been less than six or eight feet. In that part of the marsh which surrounds the Gusser el Jebha the nature of these pits is very apparent; for the ground being unequal, and overgrown with reeds and brushwood, no crust has been formed over them, and their dimensions are therefore easily ascertained. They are here very numerous, and it would be scarcely possible to escape falling into them after dark, as the paths which wind among them are sometimes not two feet in breadth, and the edges of the pits are often concealed by the vegetation which surrounds them; indeed many of these hollows are wholly overgrown, and would not be perceived by a casual observer. In crossing to the Gusser, we could not at first account for the obstinacy of our horses in refusing to quit the path, which to us appeared to wind in a most unnecessary manner, and made our ride five or six times as long as it would have been if we could have crossed to the ruin in a straight direction. But we soon found that the animals were more quick-sighted