I think I told you of the Coliseum, and its impressions on me on my first visit to this city. The next most considerable relic of antiquity, considered as a ruin, is the Thermæ of Caracalla. These consist of six enormous chambers, above 200 feet in height, and each inclosing a vast space like that of a field. There are, in addition, a number of towers and labyrinthine recesses, hidden and woven over by the wild growth of weeds and ivy. Never was any desolation more sublime and lovely. The perpendicular wall of ruin is cloven into steep ravines filled up with flowering shrubs, whose thick twisted roots are knotted in the rifts of the stones. At every step the aerial pinnacles of shattered stone group into new combinations of effect, and tower above the lofty yet level walls, as the distant mountains change their aspect to one travelling rapidly along the plain. The perpendicular walls resemble nothing more than that cliff of Bisham wood, that is overgrown with wood, and yet is stony and precipitous--you know the one I mean; not the chalk-pit, but the spot that has the pretty copse of fir-trees and privet-bushes at its base, and where H * * and I scrambled up, and you, to my infinite discontent, would go home. These walls surround green and level spaces of lawn, on which some elms have grown, and which are interspersed towards their skirts by masses of the fallen ruin, overtwined with the broad leaves of the creeping weeds. The blue sky canopies it, and is as the everlasting roof of these enormous halls.