The object of this paper was to shew, that if it be assumed that glaciers had actually existed among the Cuchullin Hills, or in other parts of this country, one of two conditions must necessarily have been present—either a climate much colder than the existing climate of Scotland, or a higher position of the land where the supposed marks of glaciers are seen. With respect to the first condition, the permanency of the relative positions of the heavenly bodies, and of the inclination of the earth's axis, and the adaptation to existing climates of animal and vegetable life, were appealed to as rendering it improbable. The other condition was maintained as probable, on the ground that the changes which have undoubtedly taken place in the positions of the rocky masses forming the crust of the earth, prove that parts of these masses had been depressed, while others had been elevated; so that the probability was, that the Cuchullin Hills had stood at a higher elevation than they do at present, reaching above the line of perpetual congelation.