What is an _aeon_? In the use and acceptation of the Apocalypse, it is evidently this, viz., the duration or cycle of existence which belongs to any object, not individually for itself, but universally in right of its genus. Kant, for instance, in a little paper which I once translated, proposed and debated the question as to the age of our planet the Earth. What did he mean? Was he to be understood as asking whether the Earth were half a million, two millions, or three millions of years old? Not at all. The probabilities certainly lean, one and all, to the assignment of an antiquity greater by many thousands of times than that which we have most idly supposed ourselves to extract from Scripture, which assuredly never meant to approach a question so profoundly irrelevant to the great purposes of Scripture as any geological speculation whatsoever. But this was not within the field of Kant's inquiry. What he wished to know was simply the exact stage in the whole course of her development which the Earth at present occupies. Is she still in her infancy, for example, or in a stage corresponding to middle age, or in a stage approaching to superannuation? The idea of Kant presupposed a certain average duration as belonging to a planet of our particular system; and supposing this known, or discoverable, and that a certain assignable development belonged to a planet so circumstanced as ours, then in what particular stage of that development may we, the tenants of this respectable little planet _Tellus_, reasonably be conceived to stand? Man, again, has a certain _aeonian_ life; possibly ranging somewhere about the period of seventy years assigned in the Psalms. That is, in a state as highly improved as human infirmity and the errors of the earth herself, together with the diseases incident to our atmosphere, &c., could be supposed to allow, possibly the human race might average seventy years for each individual. This period would in that case represent the '_aeon_' of the _individual_ Tellurian; but the '_aeon_' of the Tellurian RACE would probably amount to many millions of our earthly years; and it would remain an unfathomable mystery, deriving no light at all from the septuagenarian '_aeon_' of the individual; though between the two _aeons_ I have no doubt that some secret link of connection does and must subsist, however undiscoverable by human sagacity.