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That the lower strata are the oldest, the uppermost the most recent, is a truth independent of all circumstances but the fact of the rocks being stratified and of aqueous origin: but what is the interval of time? Whether it was long or short—a day or a thousand years—how much older one rock is than another—if ascertainable at all, cannot be known without adding to the fact of the order of succession a number of other circumstances, characteristic not merely of succession, but of duration.

The circumstances which help to define our notions of the time elapsed in the formation of the crust of the globe,—to translate, as it were, the symbolical notation of the geological scale of time into intelligible periods, having relation to the duration of the human race,—are various, and all concur in impressing the mind of a candid reasoner with ever growing convictions of the immense antiquity of the globe; the many long periods of geological changes which it has experienced before arriving at the state when, in the magnificent language of holy writ, it was said to be expressly re-arranged for the creation of man, and the present system of terraqueous conditions.

The historic records of man's residence on the earth are, for most parts of the globe, utterly incomplete; so that, but for the Jewish Scriptures and other documents of eastern nations, we should be in danger of attributing to the human race an origin too recent by thousands of years. Now, as all historic records end, for each country, with the surface,—terminate at some point of man's history posterior to the preparation of that tract for his residence, we see how far more ancient than the historic date of the human race is the series of productions which lie below the surface. The limit of least antiquity of the scale of geological time is in every country