Page:Popular Science Monthly Volume 30.djvu/551

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FULGURITES, OR LIGHTNING-HOLES.
531

ly called Senne. He also describes them as having been found in similar situations in Pillau, near Königsberg, in Prussia; at Nietleben, near Halle; and at Drigg, in Cumberland, England. In a subsequent paper, two years later,[1]* he further describes other tubes found at Rheine, in the bishopric of Münster, in Prussia; the sand-hills of Regenstein, near Blankenburg, in the Harz; and near Bahia, in Brazil. Fiedler is followed in his turn by Gilbert,[2] who gives a history of the finding of the fulgurite at Massel, as above noted, and also those of Bahia, in Brazil. An excellent résumé of the matter up to 1821 is given in the "Ann. de Chemie et de Physique" for that year,[3] and also brief descriptions of the fulgurites formed on solid rock, as described by Saussure and Humboldt.

The tubes found in Cumberland were three in number, and were formed in a white and reddish quartz-sand, in which were a few pebbles of "hornstone porphyry." One of the tubes was followed down to a depth of twenty-nine feet, where it came in contact with a fragment of the porphyry, and glanced off at an angle of about forty-five degrees. The surface of the porphyry fragment was somewhat fused, forming an olive-green glass. Beyond the fragment, the tube resumed its vertical direction, but became weaker and easily broken. The caving in of the sand prevented exploration to a greater depth. One of these tubes was two-pronged, and the main branch was again divided into two, while small, lateral branches, two or three inches long, were given off at intervals.

The account of the occurrence and appearance of the tubes found at Massel, as given by Hermann in 1811, and as quoted by Gilbert, is as entertaining as it is inaccurate. He says: "The glass-like tube resembles molten glass or iron. It grows in yellow sand from the depth of the earth at Massel, on the south side of the Töpel Hill, and also in the Ellgutten wood, and on the high sand-hills close to the village of Klein Schweinern. The tube has sometimes the thickness of a finger or a thumb; at other times it is as thick as a quill-pen, and the deeper one goes, the thicker and stronger it is found(?). Its constituent parts are very soft when underground, but soon become hard by exposure to the air, and have the appearance of a gritty, ash, or iron-colored enamel, glisten like crystal at the point of fracture, give a clear, ringing sound, and cut glass. It is hollow, shines like glass, and has a reddish-brown color. It is not found near the surface, but only after digging several ells into the ground. In the months of May or June it naturally pushes upward, and crops out of the sand. This point afterward breaks off of its own accord, or is knocked off by the feet of passing people, cattle, or vehicles, by means of which many a beautiful piece is found"(?).

  1. "Ann. der Physik.," vol. Ixi, 1819, p.235.
  2. Ibid., vol. Ixi, 1819, p.249.
  3. "Sur des tubes Vitreux qui paraissent products par des comps de foudre." "Ann. Chem.," etc., p.290.