Here is the fitting place for appropriate and most grateful mention of the results of a labor of devoted zeal and love given by the Rev. Henry Martyn Dexter, D.D., to the historic memorial of a cause of which he inherits the full spirit, and in the service of which he has spent his mature life. It may safely be said that not a single person, at least of those born on the soil of New England, of the lineage of the Fathers has so “magnified” their cause and work as he has done. Holding with such a rooted conviction, as is his, that the Congregational polity of the Christian Church has the warrant of Scripture and of the Primitive Church, and that it best serves the sacred interests of soul-freedom and of associated religion in its institutions, works, and influence, the earliest witnesses, confessors, and martyrs in its behalf have seemed to him worthy of the most lavish labor for their commemoration. Repeatedly has he crossed the seas and plied his most diligent scrutiny of tracing and searching, as he got the scent of some tract or record in its hiding-place of private cabinet or dim old parchment. With hardly eye or thought for the usual attractions of foreign travel, his valuable leisure has been spent in following any clew which promised him even the slightest aid to clearing an obscure point, or setting right a disputed fact, or completing our information on any serious matter relating to the early history of what is now represented by Congregationalism. The Introduction to his volume, _The Congregationalism of the last Three Hundred Years, as seen in its Literature, with Special Reference to Certain Recondite, Neglected, or Disputed Passages_,[453] tells in a vigorous and hearty tone what was his aim, his course, and its method. The principal text of his volume disposes the treatment of his subject under twelve lectures, delivered by the author in the Theological Seminary at Andover, in 1876-1879. This text is elaborately illustrated by notes, with references and extracts, largely drawn from the recondite sources and the depositories already referred to. The author is careful to authenticate all his statements from prime authorities; and where obscurity or conflict of views or of evidence adduced makes it necessary, his patience and candor give weight to his judgment or decision. The extraordinary and unique element of his work is presented in his _Collections towards a Bibliography of Congregationalism_, which with the Index to its titles covers more than three hundred royal octavo pages, in close type. This contains an enumeration of 7,250 titles of publications, from folios down to a few leaves, dating between the years 1546 and 1879, which have even the slightest relation in contents, authorship, or purpose with the most comprehensive bearings of his subject in its historical development.