His notes and introductions vary in length according to the requirements of the case, for he aimed to provide such material as would prevent the necessity of reference to other works. Matters that were obscure he explained, and he wrote little comment on those that were generally understood. When he left himself so free a hand he could indulge his personal tastes somewhat also, and we are not surprised to find an especial abundance of notes on an account of the Gowrie Conspiracy which presented a perplexing problem in Scottish history. The connection of _Somers' Tracts_ with other things that Scott did has already been remarked upon.[198] That he found some sort of stimulation in all his scholarly employments is sufficiently evident to anyone who studies his work as a whole, and this fact might well serve as a motive for such study. Yet it is only fair to remember that Scott was not a novelist during these years when he was performing his most laborious editorial tasks. We are accustomed to think of the brilliant use he was afterwards to make of the knowledge he was gaining, but the motives which influenced him were those of the man whose interest in literature and history makes scholarly work seem the most natural way of earning money. "These are studies, indeed, proverbially dull," he once wrote, speaking of Horace Walpole's antiquarian researches, "but it is only when they are pursued by those whose fancies nothing can enliven."[199] _The Lives of the Novelists, and Comments on Other Eighteenth Century Writers_ The _Novelists' Library_--Writers discussed--Value of the _Lives_--General tone of competence in these essays--Scott's catholic taste--Points of special interest in the discussion--Relations of the novel and the drama--Supernatural machinery in novels--Mistakes in the criticism of Defoe--Realism--Motive in the novel--Aim of the prefaces--Scott's familiarity with eighteenth century literature. It has already been said that a large part of Scott's critical work concerned itself with the eighteenth century. Of his greater editorial labors two may be considered as belonging to that period, for Ballantyne's _Novelists' Library_, though an enterprise which was commercially a failure and which consequently remained incomplete, may from the point of view of Scott's contributions fitly be compared with the _Dryden_ and the _Swift_. Such parts as were published appeared in 1821. The bulk of the volumes and the small type in which they were printed were considered to be the cause of their failure, and it was not until the critical biographies were extracted and published separately, by Galignani the Parisian bookseller, in 1825, that they seem to have attracted notice.