The hole in which they deposit their young is formed with singular skill and deserves a particular description. They begin by raising the earth and forming a tolerably ample roof, leaving divisions or pillars at certain distances to support it, all round which they beat and press the earth, interweave it with roots and plants, and render it so firm that the water cannot penetrate it; the apartment in the hillock is above the level of the ground, and therefore less subject to accidents from slight inundations; under this they form another kind of hill, upon the top of which they lay grass and leaves as a bed for their young. Here they lay secure from wet, and the female proceeds to make their retreat equally free from danger; for all round this internal hillock she pierces holes still deeper, which part from the middle apartment like rays from a centre, and extend about fifteen feet in every direction; into these the mother makes her subterraneous excursions, and from them supplies her young with roots and insects; but they contribute still more to the general safety, for as the mole is very quick of hearing, the instant she finds her habitation attacked she takes to one of the burrows, and unless the earth be dug away by several men at once, she and her young always make good their retreat. Some authors have asserted that the mole and badger sleep the whole winter: but that this is not true with respect to the badger, we have already observed, from the traces which he leaves upon the snow; and so far is the mole from sleeping the whole winter, that she continues to raise the earth then as well as in the summer; and it is almost proverbial with the peasantry of France, that "when the mole is at work a thaw is at hand." They are indeed fond of warm places, and the gardeners often catch them round their beds in the months of December, January, and February. This animal is never to be met with in barren deserts or cold climates, where the ground is frozen for the greatest part of the year. The Siberian mole, with green and yellow hair, is of a different species from our mole, which abounds only from Sweden to Barbary; at least from the silence of travellers we may presume it is not an inhabitant of hot climates. The moles of America, particularly the red ones, are also different. The Virginian mole, however, is not unlike ours, except in the colour of the hair, which is mixed with a deep purple. In our common moles there are only two or three varieties; some are more or less brown or black, and some few we have seen entirely white. Seba mentions, and gives a figure of a mole with black and white spots[P], which he found in East Friesland, and which was rather larger than our moles.