The occurrence of shells on the highest mountains, and the remains of plants and animals, which the most superficial observer could not fail to notice, in the rocks around him, have for centuries commanded the attention and exercised the ingenuity of every student of nature. But though sparks of geological truth were from time to time elicited by speculative minds, it was not till the end of the last century that its great lights broke forth, and that it took the form and character of one of the noblest of the sciences. Without undervaluing the labors of Werner, and other illustrious foreigners, or those of our southern countrymen, Mitchell and Smith, at the close of the last century, we may characterize the commencement of the present as the brightest period of geological discovery, and place its most active locality in the northern metropolis of our island. It was doubtless from the Royal Society of Edinburgh, as a centre, that a great geological impulse was propagated southward, and it was by the collision of the Wernerian and Huttonian views, the antagonist theories of water and of fire, that men of intellectual power were summoned from other studies; and that grand truths, which fanaticism and intolerance had hitherto abjured, rose triumphant over the ignorance and bigotry of the age. The Geological Society of London, which doubtless sprung from the excitement in the Scottish metropolis, entered on the new field of research with a faltering step. The prejudices of the English mind had been marshalled with illiberal violence against the Huttonian doctrines. Infidelity and Atheism were charged against their supporters; and had there been a Protestant Inquisition in England at that period of general political excitement, the geologists of the north would have been immured in its deepest dungeons. Truth, however, marched apace; and though her simple but majestic procession be often solemn and slow, and her votaries few and dejected, yet on this, as on every occasion, she triumphed over the most inveterate prepossessions, and finally took up her abode in those very halls and institutions where she had been persecuted and reviled. When their science had been thus acquitted of the charge of impiety and irreligion, the members of the Geological Society left their humble and timid position of being the collectors only of _the materials of future generalizations_, and became at once the most successful observers of geological phenomena, and the boldest asserters of geological truth.