Many of the prodigies recorded by the ancients, admit of a natural explanation; and an attentive examination will show that a small number of causes, which may be discerned and developed, will serve for the explanation of nearly the whole of them. There are two reasons for our believing accounts of prodigies:-- 1. The number and agreement of these accounts, and the confidence to which the observers and witnesses are entitled. 2. The possibility of dissipating what is wonderful, by ascertaining any one of the principal causes which might have given to a natural fact a tinge of the marvellous. Now, as regards the first reason, the ancients have recorded various occurrences: for instance, a shower of quicksilver at Rome is mentioned by Dion Cassius, in the year 197 of our era, and a similar event is related under the reign of Aurelian. If we attend to phenomena taking place in our time, such as a shower of blood, tremendous hail stones weighing a pound each, and containing a stone within them; showers of frogs, and other almost unaccountable occurrences, we must consign them to, "the annals in which science has inserted the facts, she has recognized as such, without as yet pretending to explain them." Respecting the second reason, the deceptive appearance which nature sometimes assumes, the exaggeration, almost unavoidable, by partially informed observers, of the details of a phenomenon, or its duration; improper, ill-understood, or badly translated expressions, figurative language, and a practical style; erroneous explanations of emblematical representations; apologues and allegories adopted as real facts. Such are the causes, which, singly or together, have frequently swollen with prodigious fictions the page of history; and it is by carefully removing this envelope, that elucidations must be sought of what has hitherto been improperly and disdainfully rejected. A few examples will illustrate these several positions.