36 On the Styles of Building in ancient Italy, and 



fie name, and not applicable to any kind of stone cut in rec- 

 tangular masses, in the same way as " quader stein" is applied 

 in Germany to a species of sandstone. It is a distinct volcanic 

 production, and common more or less to all volcanos, though 

 very various in its aspect and characters. Herculaneum is 

 covered with a similar formation of modern date. Brocchi calls 

 it K tufa litoide" and remarks as to its construction, that it is 

 a compound of heterogeneous materials, containing fragments 

 of black lava, limestone, &c. It contains also white farinaceous 

 leucites, scales of brown mica, with crystals of black and green- 

 ish augite, as well as felspar. Its fracture is earthy in small 

 pieces, passing into conchoidal in the large. It is sufficiently 

 hard for many purposes of building, but is considerably liable 

 to decomposition by the atmosphere. Though differing con- 

 siderably in colour and aspect, in constitution it considerably 

 resembles the trap tufa of Arthur's Seat, near Edinburgh. 



II. Peperino, another volcanic production nearly connected 

 with the last, was brought from the Alban Mount. Its colour 

 is greenish gray, resembling ground pepper, whence its name, 

 though some say it is from Piperno, a town in the Apeninnes, 

 where it is said to abound.* It resists the air much better 

 than tufa, and is a valuable building stone, as the tear and 

 wear of near three thousand years on the Cloaca Maxima and 

 Mammertine prisons amply prove. It abounds in imbedded 

 masses, crystals (chiefly decomposed,) &c. A variety of it, 

 which, except from, locality, hardly requires separate notice, is, 



III. The Pietra Gabina, or " Saxum Gaumum," brought 

 from Gabii, twelve miles from Rome. Its colour resembles Pe- 

 perino, but it is said to be harder, and more porous, and to have 

 been used by the ancients for millstones. I must confess that 

 I am not acquainted with the characteristic distinctions of this 

 stone. It was esteemed, as well as the last, for being proof 

 against fire, on which account Nero commanded Rome to be 

 rebuilt after the great conflagration, with one or other of these 

 stones. " iEdificiaqueipsa certa sui parte, sine trabibus, saxo 

 Gabino Albanove solidarentur : quod is lapis igni impervius 

 est." — Tac. Ann. xv. 43. 



* See Burton s Antiquities of Rome. 



