During the early part of this century, architecture sank to the lowest ebb all over the world, probably owing to the disturbing influences of the great Napoleonic wars. Within the last thirty years the spirited writings of a few enthusiasts and the liberal teachings of the French schools have caused a general revival, and better work is being done now than at any time during the century. [Illustration: PLAN OF CHURCH OF THE HOTEL DES INVALIDES AT PARIS.] Avaricious commerce and the predominance of the desire for display rather than quiet love of the arts are factors which stand much in the way of genuine progress, but it is not improbable that the spread of refined education will eventually succeed in planting the seeds of this love in the heart of the great masses, and enable architecture to resume its natural and elevating position in their midst. XII. CONCLUSION. At the present stage of modern art we have the principles, broadly speaking, of two great styles of architecture to guide us in the design of the buildings which we may have to erect. These are the Classic and the Gothic; for we may apply the term Classic not merely to the works of the Greeks and Romans, but to their offshoots the Byzantine and Romanesque styles, the one branching Eastward and the other Westward, altered in many respects, but founded on the older systems; and we have seen that the Renaissance was but a revival of the same methods and forms. In each of these styles the best result has always been attained where the constructional element has been held to be as important as the decorative, where the essential and useful have not been subservient to considerations of ornament or display. In Classic work much has been done that is unworthy, in the senseless repetition of columns and pilasters which support nothing, in decoration which serves only to conceal ill-adjusted architectural lines; and the same is equally true of degenerate Gothic, in which whole walls have been covered with meaningless panels, and massive buttresses built up to receive no strain. Nevertheless, by following only what is good in the principles of each, and by avoiding the errors which experience has enabled us to perceive, especially those which have engrafted themselves upon us by bigoted custom, we can not only produce fine work but assist in the advance of architecture. Before deciding upon what style to employ in the composition of an edifice, it is well to first consider thoroughly the programme of what is wanted in its plan, and then the special character with which we desire to invest it both exteriorly and interiorly. It is scarcely necessary to add that both should be intimately connected.