It must be kept in mind that one of the most valuable forms of contemporaneous testimony, if not the most valuable of all, is a set of letters which contain various and definite allusions to the current events, habits, and modes of thought of the time. For certain purposes these are far more valuable than formal histories. The latter are frequently written under the influence of party spirit, partiality, or bias. The writer of a history is usually on his guard, has carefully considered what he says, and affords us but little opportunity of interrogating him. But the writer of a letter, unless he has special reasons for being guarded, places before his correspondent his entire mind. We are therefore capable of interrogating him. He often lets us into the secret causes of events. He also makes a number of incidental allusions to events which are passing. These form testimony of a most valuable kind. We can in a manner almost converse with him. As a confirmation of the facts which formal histories narrate, and as letting us into the secret springs of events, a series of letters, written by persons who were actively engaged in them, are historical documents of the highest order. Their value is increased when they bear all the appearance of coming from the writer’s heart. Nothing is more striking than the happy results which have accrued from the extensive use made by modern historians of original correspondence. It is not too much to say that it has largely modified our view of events, as they have been reported in formal histories. Another very high form of contemporaneous testimony is the existence of institutions and monuments which can be certainly traced up to a particular period, and which owed their existence to events of that period. These form a species of living witnesses to the truth of the facts out of which they have originated, and as far as their testimony goes, it is incapable of falsehood. The most valuable testimony of this kind is a great institution of which we possess definite evidence that it originated in a particular event, or in the belief of it. This kind of evidence Christianity possesses in the highest form, in the continued existence of that great institution, the Christian Church. 2. Testimony has a general credibility, subject of course to the knowledge and honesty of the informant, when the reports are derived from those who lived during the generation in which a particular event occurred, supposing it to have been one of sufficient notoriety to attract attention, and that the reporter possessed adequate means of information, and investigated it with sufficient care. We are always justified in assuming that he tells the truth unless there are reasons for suspecting the contrary.