temples. It was, in point of fact, _added_ to the other by means of arcades, both in the sides of the nave and in its apsidal projections, opening out mysterious perspectives into the inner recesses of the temple. This union of the more palpable with the more mysterious, of the vast unbroken expanse with the intricately broken perspective, must, as it appears to me, and as I judge from representations, produce an impression more astounding than that of almost any other building; but, when we consider the whole as clothed with the richest beauties of surface; its piers encrusted with inlaid marbles of every hue, its arcades of marble gorgeously carved, its domes and vaultings resplendent with gold mosaic interspersed with solemn figures, and its wide-spreading floors, rich with marble tesselation, over which the buoyant dome floats, self-supported, and seems to sail over you as you move--I cannot conceive of anything more astonishing, more solemn, and more magnificent. Well might its Imperial founder exclaim, when, with pardonable exultation, he viewed the result of his costly aspirations--“Glory be to God, who hath thought me worthy to accomplish so great a work; _I have vanquished thee, O Solomon_!” I have dwelt longer on my description of this wonderful building because it is _facile princeps_ among structures on the pendentive domical principle, just as the Pantheon had been among those with the simple dome; and as, in after ages, was St. Peter’s among those whose domes soared upwards as lofty towers. I must here close my lecture, leaving the continuation of my descriptive sketch of the history of the Cupola, and such remarks as I may have to offer on its uses, its practical application, and its future development, to be followed up in my next. LECTURE XVII. The Dome (_Continued_). St. Irene, Constantinople--Church of San Vitale, the type, three centuries later, of Charlemagne’s Church at Aix-la-Chapelle--Two influences at work leading to the introduction and adoption of the dome into Italy--From thence into the south-west of France--Baptisteries at Florence and Parma--Cathedral at Sienna--St. Mark’s, Venice--Santa Fosca near Venice--Domes having _pointed_ arches for their support--St. Front and La Cité, Perigueux--Angoulême--Fontevrault--Auvergne--Ainay near Lyons--Pendentives in many French churches give place to corbels--The _modern_ type of dome--Cathedral at Florence--St. Peter’s, Rome, and St. Paul’s, London. In my last lecture, after bringing down our consideration of domical construction to the period of the perfecting by the Byzantine architects of the system of what are known as “Pendentive Domes,” I was proceeding to describe a few of its most marked productions, but was stopped short when I had given a rapid sketch of the most wonderful of its creations--the Church of St. Sophia at Constantinople.