These rookeries have been often described, but as my readers may not all have seen these descriptions, and as I shall have occasion hereafter to speak of the penguin and albatross, it will not be amiss to say something here of their mode of building and living.
When the season for incubation arrives, the birds assemble in vast numbers, and for some days appear to be deliberating upon the proper course to be pursued.

At length they proceed to action.

A level piece of ground is selected, of suitable extent, usually comprising three or four acres, and situated as near the sea as possible, being still beyond its reach.

The spot is chosen with reference to its evenness of surface, and that is preferred which is the least encumbered with stones.

This matter being arranged, the birds proceed, with one accord, and actuated apparently by one mind, to trace out, with mathematical accuracy, either a square or other parallelogram, as may best suit the nature of the ground, and of just sufficient size to accommodate easily all the birds assembled, and no more--in this particular seeming determined upon preventing the access of future stragglers who have not participated in the labor of the encampment.