“The Bass is an abrupt rock, having a basis of about a mile in circumference, and of an oblong form. The cliffs are perpendicular in some places, overhanging in others, and everywhere precipitous, excepting at the narrow extremity next the land, where, sloping less abruptly, they form at the base a low projection, on which is the only landing-place. Above this are the ruins of the fortifications and houses, the Bass having formerly been used as a State-prison. The rocks are in some places apparently two hundred feet in height, and the summit, towards which the surface rises in an irregular manner, is probably a hundred and fifty feet higher. In as far as I observed, the whole mass is of a uniform structure, consisting of trap, intermediate between greenstone and clinkstone, of a dull brownish-red colour, and small granular structure. Although a great portion of the upper surface of the island is composed of rock, there is an abundant vegetation, consisting chiefly of _Festuca ovina_, _F. duriuscula_, and a few other grasses, mixed with the plants usually found in maritime situations. “The circumstance connected with the Bass most interesting to the Zoologist, is its being one of the few places in Britain to which the Gannet resorts during the breeding season. The number which I saw on the 13th May 1831, when I for the first time visited it along with some friends, might be estimated at twenty thousand. Every part of the mural faces of the rock, especially towards their summits, was more or less covered by them. In one spot near the landing place, about forty yards in circumference, and on a gentle slope of gravelly ground, about three hundred individuals were sitting in peaceful security on their nests.