14 Account of' the 



The red variety was the best, and was found at the Tre Fon- 

 tane, a short way from Rome, on the road to Ostia, where it is 

 dug at this day. It was employed in the mortar of the oldest 

 Roman edifices. Sometimes it assumes the form of clay; and 

 bricks and coarse pottery used to be, and are now, made of it. 



At the foot of the Capitoline hill there was a street called 

 jTgiletum, which Varro says got its name, according to the 

 opinion of some, from clay being found there : " Argiletum — 

 alii ab argilla, quod ibi id genus terrae.*" — Lib. v. The clay 

 pits were most probably in the Inter montium. 



The Palatine Hill — is, like the Capitoline, insulated. It is 

 ten feet higher than the Capitoline, and divided into two sum- 

 mits ; the one of which was called Termalus, the other Velia. 

 It is hardly possible to discover the external structure of this 

 hill, it is so thickly covered by soil and the rubbish of ruins, 

 and there being scarcely any excavations in it. The granular 

 tufa has been found in it, and it is very probable that it is co- 

 vered with fresh water deposits, like the other hills. 



The Pincia/n Hill. — This hill, formerly called the CoUis 

 Hortulorum, is the first which flanks the left bank of the river, 

 and rises nearly 200 feet above it. Several excavations have 

 been made in different parts of it, so that its structure has been 

 fully made out. 



1. The lowest part is composed of granular tufa, and this has 

 not been dug through. It contains calcareous concretions, with 

 impressions of arundinaceous plants, and the tufa itself contains 

 impressions of leaves of trees. 



2. Next comes a bed of clay three feet thick, with impressions 

 of leaves, the materials of the clay being evidently derived from 

 a disintegrated tufa. 



, 3. Above this is a granular tufa, mixed with pebbles of the 

 Apennine limestone; a thin bed of fragments of pumice lies 

 over the tufa. 



4. These are all covered by a vast deposit of sand, formings 

 as it were, a mantle over the whole hill, the great external mass 

 being the granular tufa. The sand is siliceo-calcareous^ and 

 contains a great quantity of calcareous concretions, similar to 

 those deposited by calcareous petrifying springs, detached peb- 

 bles, beds of limestone gravel, and masses of travertine* with 



