a bawl-nut in size; but, in a great bill, are often of a considerable magnitude. In the multitude of apartments, some contrivance is necessary to facilitate the communication with the distant parts of the nest; accordingly, they build a kind of bridge, of one vast arch, which answers the purpose of a flight of stairs, from the floor of the area to some opening on the side of one of the columns which support the great arches, and diminishes the fatigue of those labourers, to whom the task is assigned of carrying the eggs from the royal chamber to some of the upper nurseries.
Their labours are not entirely confined to the interior of their hillocks, but they carry out large subterranean passages, in various directions, and to a great extent. Mr. Smeath man measured one of them thirteen inches in diameter. These subterranean passages or galleries, are thickly lined with the same kind of clay of which the hill is composed, and as scend the inside of the outward shell in a spiral manner; winding round the building till they reach the top, and intersecting each other at different heights, open into the dome or the interior building. From every part of these large galleries, various smaller ones proceed, and form a communication with the different parts of the building. Many of them
descend
