GEOLOGY. 335 



it continues to run. This arm of the Colorado might be made permanent, 

 but a far more convenient supply could be furnished by Artesian wells, or, 

 better still, by windmills raising water from common wells, as is now so 

 successfully practised throughout the fertile valley of San Jose'. 



EARTHQUAKE PHENOMENA IN SOUTHERN ITALY. 



One of the most terrible earthquakes experienced in Southern Italy during 

 the present century occurred in the kingdom of Naples on the night of the 

 16th of December, 1857, a season of the year which, by a comparison of all 

 the known dates of earthquakes, has been ascertained to be more subject to 

 disturbances than any other. The sky was clear, the air still; indeed, unu- 

 sual stillness had prevailed the whole of that day. A sharp undulatory 

 shock of twenty seconds' duration, immediately preceded, and, accompanied 

 by a hollow, rumbling noise, had scarcely awakened the inhabitants, who 

 had generally retired to rest, when, after a hardly perceptible pause of about 

 three minutes, a second and most violent successive shock of twenty-five 

 seconds' duration crushed thousands of them under the ruins of their falling: 



^5 



houses. The seat of this earthquake was in the central group of mountains 

 in the provinces of Basilicata and Principato Citra, part of the main chain 

 of the Apennines, which are the watershed between the streams flowing into 

 the Tyrrhenian, the Ionian, and the Adriatic Sea, and form the upper basins 

 of the Calore or Tanagro, the Sele, the Ofanto, the Bradano, the Basento, 

 the Sinno, and the Agri rivers. The centre of action, as far as it can be 

 judged from the intensity of its terrific effects, was almost in the heart of 

 the province of Basilicata, in a group of compact limestone mountains of 

 the cretaceous period, the southern branch of the said central group, which, 

 running from north to south between the heads of the valleys of the Sinno 

 and the Agri on the east, and the valley of Diano on the west, swells further 

 south into the lofty peaks of Monte Cocuzzo, Monte del Papa, and Monte 

 Pollino, on the frontiers of Calabria. On the declivities or lower peaks of 

 this group, which are covered with beds of tertiary marine marl, sands and 

 conglomerate, and within a district extending over an area of about 210 

 square miles, stand, or rather stood, the towns and villages of Monternurro, 

 Saponara, Viggiano, Tramutola, Marsico Vetere, Marsico Nuovo, Spinosa, 

 and Sarconi, with an aggregate population of 35,570. Out of this number 

 more than 12,000, or more than one-third, in less than half a minute were 

 crushed to death; 2,000 severely wounded ! The ground was cracked and 

 convulsed in the strangest manner; chasms and deep fissures were opened 

 in several places, fertile hills became bare rocks, valleys were raised up, 

 small pools formed, mountains cleft by deep ravines. The towns of Monte- 

 murro and Saponara, especially, were nearly entirely swept away ; the former 

 lost 5,600 out of 7,000, and the latter 3,000 out of 4,000 inhabitants. Sapo- 

 nara, which rose in the Middle Ages out of the ancient Grumcntum, where 

 Hannibal sustained a slight defeat by the Consul Claudius Nero, was almost 

 entirely levelled with the ground; there remain only a few shattered houses 

 standing. Of Montemurro, originally a Saracenic settlement of the tenth 

 century, literally nothing was left but a heap of rubbish. On the morning 

 of the 17th of December, 5,600 of its inhabitants were dead or dying under 

 the ruins, 685 disabled by wounds ; the few remaining unhurt found them- 

 selves torn from their dearest ones, houseless, amidst a mass of ruins, with- 

 out means of subsistence or help, and exposed to all the inclemency of a 



