Much might be written on the conflicting opinions expressed by historical, biographical, and scientific writers, regarding the intellectual capacity and ingenuity of the Marquis as well as of their adverse statements on various historical points. But instead of adopting such a thoroughly controversial strain, which after all would only lead to a very doubtful result, another and very different course has been adopted in the present work, by supplying facts in place of conjecture. The writer, who is strongly imbued with political, theological, or scientific views, cannot write otherwise than as directed by the natural effect of such influences. But as a rule the arena of scientific discussion is neutral ground; and the biographer and commentator, in the present instance, does not feel swayed by any party prejudice, and certainly not by any peculiar scientific views. It has been his wish to associate himself as much as possible with the Marquis and with his times, irrespective of modern taste, changed customs, and enlarged knowledge, as contrasted with a period about the middle of the seventeenth century. Here the critic rises in importance with the information he possesses of a bygone age. But it has been so uniformly the misfortune of the Marquis of Worcester to be examined solely through a modern medium, that it is almost surprising his antiquated costume, and style of writing, should have escaped the generally reckless course of censure bestowed on the precious relics that alone remain to attest his amazing genius. Every work descriptive of the Steam-engine, gives some historical notice, awarding a certain amount of dubious merit to the Marquis of Worcester, among other early inventors, but it would be impossible to point to a single instance savouring of any national pride in the inquiry. It seems incredible, and might be believed to be so, had we not the fact before our eyes, that the true history of the origin of the Steam-engine is only now emerging into light in the form best calculated to place the fact beyond dispute. Like all other great inventions, the improvements in the Steam-engine have been progressing from 1663 to the present day. Its history presents three eras:--1st, the period when the parent engine and its immediate successors were called “fire engines;”--2nd, from Newcomen’s time, when that stage of improvement was designated the “atmospheric-engine;” and, 3rdly, its last form, the true “steam-engine” of Watt. We cannot destroy one link in this mystic chain without serious hazard, without deranging the natural consanguinity of these children of the brain. But while we consider it unnecessary to deal singly with each work contributing an apocryphal history to the origin of the steam-engine, a solitary instance occurs, within the last five years, the publication of which demands special notice.