Chap. IV.
HOMAN.
151
frame itself contignationes. The joists or sleepers were termed coaxationes or cassationes,and were made of an oak called esculus, because it was not subject to warp or shrink.To protect this timber from the effect of the lime mixed with the other materials, theycovered it with a bed of rushes or reeds, and sometimes straw. On this stratum of reedsor straw was laid the statumen or foundation.
The second bed was made of broken stones mixed with lime, which Isidore calls rudus.When this material was composed of stones freshly broken, it was called rudus novum ; tothree-fourths was added one-fourth of quick-lime. Hut when the material came fromold buildings, it was called rudus redivivum, and thei^ an additional portion of lime wasused, two parts to five, and the work termed ruderationem ; the rammer or beater wasemployed to strengthen, equalise, and smooth it. This composition, whether formed ofgravel or debris, was 9 inches in thickness after it was thoroughly rammed. Over thistarras or ruderation, a cement was laid for the third bed, composed of brick, potsherds,broken tiles mixed with lime, using one of lime to three of brick. This was spread overthe ruderation in a thin layer, to receive the fourth bed or paving, which served as acovering to the entire work, and was called in consequence summam crustam. Thethird bed or nucleus was the softest layer of the wdiole, interposed between what w r as harder.The stones and cement which formed the road were not less than 6 inches in thickness,and the entire mass laid upon the framework of carpentry was 15 inches.
The unpaved roads of the Romans were called by Ulpian vias terrenas, to distinguishthem from those dressed with stone or gravel; and they w'ere regulated by similar lawsand ordinances as the others. The road from Spain into Italy , through Nismes, wasof this kind, and only passable during the summer months. In the winter and spring, itwas in a soft state, from the water which came down from the neighbouring mountains,though Strabo mentions several wooden and stone bridges and ferries.
These roads, so liable to be broken up by the torrents, were exposed to the action ofthe sun and wind, all shade being removed, that they might speedily dry.
Appian Way , or road to Capua, a distance of 120 miles, was paved with polygons of lava.In a.u.c. 451, the first mile, from the Porta Capena to the temple of Mars, was paved as away for walking and riding on horseback (semita), with hewn stones (pepperino); and ina. u. c. 453, the whole road was paved with lava as far as Bovillze. (Livy x. 23. 47.) Semita ,signifies without any reference to width, a cordonata , or a road up-hill, made with sunkenbroad and low steps, where sumpter cattle walk safely and comfortably ; carriages, if at all,can only come down : clivus is a carriage road. A well-known inscription tells us, that there
Fig.164.
was a clivus on the Appian road, near the temple of Mars, by the side of which the semitanow necessarily assumed the form of a cordonata.
The Alta Semita, which led from the Subura along St. Agata to the Quirinal HiJl, wassuch as the locality clearly shows. We find, in the gates of the so-called Cyclopeantowns, Homan or Latin cordonatas, constructed entirely on the same plan as in the presentday.
The Appian Way is remarkable for its foundations, its constructions over deep valleys
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