Plate I. FIGS. 1, 3 AND 5. ILLUSTRATIVE DIAGRAMS 219 " II. " 2. WINDOW IN OAKHAM CASTLE 221 " III. " 4 AND 6. SPRAY OF ASH-TREE, AND IMPROVEMENT OF THE SAME ON GREEK PRINCIPLES 226 " IV. " 7. WINDOW IN DUMBLANE CATHEDRAL 231 " V. " 8. MEDIÆVAL TURRET 235 " VI. " 9 AND 10. LOMBARDIC TOWERS 238 " VII. " 11 AND 12. SPIRES AT CONTANCES AND ROUEN 240 " VIII. " 13 AND 14. ILLUSTRATIVE DIAGRAMS 253 " IX. " 15. SCULPTURE AT LYONS 254 " X. " 16. NICHE AT AMIENS 255 " XI. " 17 AND 18. TigER'S HEAD, AND IMPROVEMENT OF THE SAME ON GREEK PRINCIPLES 258 " XII. " 19. GARRET WINDOW IN HOTEL DE BOURGTHEROUDE 265 " XIII. " 20 AND 21. TREES, AS DRAWN IN THE THIRTEENTH CENTURY 294 " XIV. " 22. ROCKS, AS DRAWN BY THE SCHOOL OF LEONARDO DA VINCI 296 " XV. " 23. BOUGHS OF TREES, AFTER TITIAN 298 THE SEVEN LAMPS OF ARCHITECTURE PREFACE. The memoranda which form the basis of the following Essay have been thrown together during the preparation of one of the sections of the third volume of "Modern Painters."[A] I once thought of giving them a more expanded form; but their utility, such as it may be, would probably be diminished by farther delay in their publication, more than it would be increased by greater care in their arrangement. Obtained in every case by personal observation, there may be among them some details valuable even to the experienced architect; but with respect to the opinions founded upon them I must be prepared to bear the charge of impertinence which can hardly but attach to the writer who assumes a dogmatical tone in speaking of an art he has never practised. There are, however, cases in which men feel too keenly to be silent, and perhaps too strongly to be wrong; I have been forced into this impertinence; and have suffered too much from the destruction or neglect of the architecture I best loved, and from the erection of that which I cannot love, to reason cautiously respecting the modesty of my opposition to the principles which have induced the scorn of the one, or directed the design of the other. And I have been the less careful to modify the confidence of my statements of principles, because in the midst of the opposition and uncertainty of our architectural systems, it seems to me that there is something grateful in any _positive_ opinion, though in many points wrong, as even weeds are useful that grow on a bank of sand.