- Zacatecas, silver mine of, [302]
- Zealand, New, effects of the earthquake of 1855 in upraising land, [111]
- Zellerfeld, great adit levels of the mines of, [270]
- Zepeda, Don Barnebé de, his discovery of the silver vein of Catorce, [303]
- Zeus, Olympian, Phidias’ ivory and gold statue of, [286]
- Zinc, not known to the ancients, [380]
- Zircon, the, [492]
- Zoroaster, religion of, restored by the Sassanides of Persia, [92]
- Zwickau, in Saxony, burning mine at, [283]
Footnotes
[3]. A siphon, as is well known, is a bent tube, having one leg longer than the other. When this tube is filled with any liquid, and the shorter end is immersed in a vessel containing liquid of the same kind, the weight of the column in the longer leg will cause the liquid to begin to run out, and it will continue running till the vessel is emptied. This arises from the pressure of air on the exposed surface of fluid, forcing it up through the tube to prevent vacuum, which would otherwise be formed at the highest point; and the extreme limit of length at which the siphon will act is therefore determined by the height of a column of the fluid equal to the pressure of the atmosphere (fifteen pounds on the square inch). The limit in the case of water is something more than thirty feet.
[4]. ‘The Polar World,’ p. 54.
[5]. Liebig’s ‘Annalen,’ translated in ‘Reports and Memoirs of the Cavendish Society,’ London, 1848, p. 351.
[6]. See Chapter on Mines in general, for a short account of earth-boring operations.
[7]. ‘Die vulcanischen Erscheinungen der Erde.’ Liepzig, 1865.