Both in dimensions and design they form a perfect contrast to the Pantheon, as might be expected from their both belonging to the Augustan age of art: consequently the cella is small, its interior is unornamented, and all the art and expense is lavished on the external features, especially on the peristyle; showing more strongly than even the rectangular temple the still remaining predominance of Grecian taste, which was gradually dying out during the whole period of the Empire. It is to be regretted that the exact dates of both these temples are unknown, for, as that at Tivoli shows the stoutest example of a Corinthian column known and that in Rome the slenderest, it might lead to some important deductions if we could be certain which was the older of the two. It may be, however, that this difference of style has no connection with the relative age of the two buildings, but that it is merely an instance of the good taste of the age to which they belong. The Roman example, being placed in a low and flat situation, required all the height that could be given it; that at Tivoli, being placed on the edge of a rock, required as much solidity as the order would admit of to prevent its looking poor and insecure. A Gothic or a Greek architect would certainly have made this distinction. One more step towards the modern style of round temples was taken before the fall of the Western Empire, in the temple which Diocletian built in his palace at Spalato. Internally the temple is circular, 28 ft. in diameter, and the height of the perpendicular part to the springing of the dome is about equal to its width. This is a much more pleasing proportion than we find in the Pantheon; perhaps the very best that has yet been employed. Externally the building is an octagon, surrounded by a low dwarf peristyle, very unlike that employed in the older examples. This angularity is certainly a great improvement, giving expression and character to the building, and affording flat faces for the entrances or porches; but the peristyle is too low, and mars the dignity of the whole.[171] [Illustration: 194. Plan and Elevation of Temple in Diocletian’s Palace at Spalato. Scale for Plan 100 ft. to 1 in.; for Elevation 50 ft. to 1 in.] To us its principal interest consists in its being so extremely similar to the Christian baptisteries which were erected in the following centuries, and which were copies, but very slightly altered, from buildings of this class. ATHENS.