Chapel of St. John, Tower of London--St. Alban’s Abbey--St. Stephen’s at Caen--Cathedrals of Winchester, Ely, London, Rochester, and Norwich--Abbey Church at Bury St. Edmund’s--Gloucester Cathedral--Tewkesbury Abbey--Cathedrals of Worcester and Durham--Waltham Abbey--Christchurch, Hants Page 92 LECTURE XIII. The Practical and Artistic Principles of Early Architecture in Great Britain. The close of the eleventh century--The “new manner of building”--Conditions necessary to an _arcuated_, as distinguished from a _trabeated_, style--First principles of Grecian and Roman architecture--Rationale of the _arcuated_ style--Its developments--Cloisters of St. Paul without the Walls and St. John Lateran, Rome--Doorways--Windows--Vaulting over spaces enclosed by walls or ranges of piers--Simplest elements defined--Barrel-vaults--Hemispherical vaults or _domes_--Groined vaults Page 133 LECTURE XIV. The Principles of Vaulting. Vaulting of spaces of other forms than the mere square--Apsidal aisles, St. John’s Chapel, Tower, and St. Bartholomew’s Church, Smithfield--Chapter-house and crypt, Worcester--Round-arched vaulting in its most normal form, as resulting from the _barrel_ vault and its intersections--Short digression on another simple form of vault, the _dome_--“Domed up” vaults--“Welsh” groining--The square or polygonal dome--The Round-arched style of the twelfth century almost perfect--First introduction of the Pointed arch into vaulting--Names of the parts of groined vaulting--Two specimens in London of the apsidal aisle, one in the Round-arched, the other in the Pointed-arched style--Vaulting a polygon with a central pillar--_Ploughshare_ vaulting--The artistic sentiment and character of early Gothic vaulting Page 161 LECTURE XV. The Principles of Vaulting--_continued_. Certain practical points concerning vaulting--Ribs of early and late vaulting--Filling in of intermediate surfaces or cells--Methods adopted in France and England--Sexpartite vaulting--Crypt of Glasgow Cathedral--Choir at Lincoln--Chapter-house, Lichfield--Caudebec, Normandy--Octagonal kitchen of the Monastery, Durham--Lady Chapel, Salisbury--Segmental vaulting--Temple Church--Lady Chapel, St. Saviour’s, Southwark--Westminster Abbey--Intermediate ribs--Presbytery at Ely--Chapter-houses of Chester and Wells--Exeter Cathedral--Cloisters, Westminster--“Liernes”--Ely Cathedral--Chancel, Nantwich Church--Crosby Hall and Eltham Palace--Choir at Gloucester--Winchester Cathedral--Fan-vaulting--Cloisters at Gloucester--King’s College Chapel, Cambridge--Divinity Schools, Oxford--Roof of Henry VII.’s Chapel, Westminster--Ideal of its _design_ Page 190 LECTURE XVI. The Dome.