As more than a quarter of a century has elapsed since the second volume of this work was published, I venture to offer a brief explanation of the protracted delay that has attended the appearance of the third, notwithstanding that continuous residence in the university throughout that time has greatly facilitated access to the original sources of information and especially those relating to the history of the colleges. The primary cause, I need hardly say, has been my engagements as lecturer and librarian at my own College, and also as lecturer on history to the University, on ecclesiastical history, as Birkbeck lecturer at Trinity College, and lecturer on the History of Education to the Teachers' Training College. A contributing cause has been one which could hardly be foreseen,—the publication of the Dictionary of National Biography. As soon as, in 1885, the first volume of that monumental work appeared, and I was myself privileged to become a not infrequent contributor, I could not fail to perceive, not only that I should gain largely by awaiting the completion of the series, but that such a course was almost indispensable.