MISCELLANEOUS. 211 



date, new cones have been thrown up in these valleys, — new lakes have been 

 formed by the damming up of rivers ; — and more than one creation of quadrupeds, 

 birds and plants, Eocene, Miocene and Pliocene, have followed in succession ; 

 yet the region has preserved from first to last its geographical identity ; and we 

 can still recall to our thoughts its external condition and physical structure 

 before these wonderful vicissitudes began, or while a part only of the whole had 

 been completed." The whole region consists in large measure of granite and 

 crystalline rocks, and is full of vestiges of most intense volcanic action — presenting 

 multitudes of truncated cones of scoriae and ashes, apparently quite fresh, 

 trachytic domes, basaltic colonnades and plateaux of immense extent. Some of 

 these volcanoes (as Puy de Dome and Puy de Sarcouy), are characteristic speci- 

 mens of that class of mountains which, though volcanic, appear never to have 

 been, properly speaking, in eruption. The material (trachyte, domite,.etc.) issued 

 from the earth, apparently, in so imperfect a state of fluidity as not to run, but 

 to form rounded masses. According to Lyell, these extinct volcanoes began their 

 eruptions so called, in the Upper Eocene period, but were most active during the 

 Miocene and Pliocene eras ; the latest eruptions occurred at the close of the 

 Newer Pliocene, if not in the Post Pliocene period. 



This region, displaying as it does so remarkably the grand succession of 

 events in Central France since the last retreat of the sea, and illustrated by the 

 masterly researches of Scrope, Lyell and Murchison, is perhaps the finest field in 

 the world for the study of extinct volcanic action. This large Relief Map is a 

 copy of the one made by G. Poulett Scrope, F. R. S. and deposited in the 

 Rooms of the British Geological Survey, London. 



Size, 5 ft. 6 in. x4ft. 9 in. Price, $75.00. 

 In glass-case, ,$100.00. 



No. 1239. Relief Map of Vesuvius. 



The Map shows a portion of the Bay of Naples, and the slope of the volcano 

 on all sides from its crater to the plain. The steep, semi-circular escarpment of 

 Monte Somma, and the modern cone of Vesuvius which it faces, rise in bold 

 relief; and the various lava currents which have been ejected — from that which 

 overwhelmed Herculaneum to the eruption of 1820, are represented with their 

 dates. Size, 2 ft. x 2 ft. 6 in. Price, $10.00. 



No. 1240. Relief Map of Etna. 



This celebrated volcano — the loftiest in Europe — rises near the sea to 

 the height of nearly 11.000 feet. The most striking and original feature 

 in its physiognomy is the multitude of minor cones distributed over its 

 flanks. They number about eighty, and throw out sulphurous vapors. The 

 modern lavas overlie the ancient basaltic masses and sedimentary deposits 

 of Mesozoic and Tertiary ages. Near the summit of Etna is the Val del Bove — 

 a famous gorge of magnificent dimensions, a vast amphitheatre four or five miles 

 in diameter, surrounded by nearly vertical precipices from 1,000 to 3,000 feet, 

 high. This very accurate map was modeled after the one constructed on the spot 



by Elie de Beaumont, the noted French Geologist. 



Size. 17 x 16. Price, $6.00. 

 No. 1241. Relief Map of Teneriffe. 



This volcanic peak stands, says Von Buch, like a tower encircled by its fosse 

 and bastion, — the bastion consisting of precipitous cliffs which, according to the 

 theory of that geologist, were heaved up into their present position by a force 



