and 1805 is almost as striking as that of those taken from 1816 to 1822. In the latter period we cannot doubt the height being from about 621 to 629 toises (3970 to 4022 English feet). Are the measurements made from thirty to forty years earlier, which gave only 606 to 609 toises (3875 to 3824 English feet), less certain? At some future day, after longer periods shall have elapsed, it will be possible to decide what is due to errors of measurement, and what to an actual rise in the margin of the crater. There cannot be in this case any accumulation of loose materials from above. If the solid trachyte-like lava beds of the Roca del Palo really become higher, we must assume them to be upheaved from below by volcanic forces. My learned and indefatigable friend Oltmanns has placed all the details of the above measurement before the public, accompanied by a careful critical examination of them, in the Abhandl. der königl. Akademie der Wissenschaften zu Berlin, 1822-1823, S. 3-20. May this investigation be the means of inducing geologists frequently to examine hypsometrically this low and most easily accessible (except Stromboli) of the European volcanos, so that in the course of centuries there may be obtained a frequently checked and accurate account of its periods of development! (2) p. 235.-" Where the pressure is less." Compare Leopold von Buch on the Peak of Teneriffe in his Physikalische Beschreibung der canarischen Inseln, 1825, S. 213; and in the Abhandlungen der königl. Akademie zu Berlin, 1820-1821, S. 99. (3) p. 239.-" Waters of springs rising from different depths." Compare Arago in the Annuaire du Bureau des Longitudes pour 1835, p. 234. The increase of temperature is in our latitudes 1° of Reaumur (2°.25 of a degree of Fahrenheit) for every 113 Parisian feet (120.5 English feet), or 1° Fah. to 53.5 English feet nearly. In the Artesian boring at New Salzwerk (Oeynhausen's Bad), not far from Minden, which is the greatest known depth below the level of the sea, the temperature of the water at 2094 Parisian feet (2232 Eng.) is fully 26°.2 Reaumur, or 91° Fahr.; while the mean temperature of the air above may be taken at 70.7 Reaumur, or 49°.2 Fahr. It is very remarkable that in the third century Saint Patricius, Bishop of Pertusa, was led by seeing the hot springs near Carthage to a very just view respecting the cause of such an increase of heat. (Acta S. Patricii, p. 555, ed. Ruinart; Kosmos, Bd. i. S. 231,-English Edition, Vol. i. p. 211.) THE VITAL FORCE, OR THE RHODIAN GENIUS. THE Syracusans, like the Athenians, had their Pœcile, in which representations of gods and heroes, the works of Grecian and Italian art, adorned the halls, glowing with varied colours. The people resorted thither continually; the young warriors to contemplate the exploits of their ancestors, the artists to study the works of the great masters. Among the numerous paintings which the active zeal of the Syracusans had collected from the mother country, there was one which, for a century past, had particularly attracted the attention of spectators. Sometimes the Olympian Jove, Cecrops the founder of cities, and the heroic courage of Harmodius and Aristogiton, would want admirers, while men pressed in crowded ranks around the picture of which we speak. Whence this preference? Was it a rescued work of Apelles, or of the school of Callimachus? No; it possessed indeed grace and beauty; but yet neither in the blending of the colours, nor in the character and style of the entire picture, could it be compared with many other paintings in the Pœcile. The multitude (comprehending therein many classes of |