QIBB — A CHAPTER ON FOSSIL LIGHTNING. 



199 



twelve to eighteen inches from their roots, melted quartzose matter, 

 and vitrified tubes, of a flattened form with zigzag projections. Our 

 wonder is, that such manifestations of the effects of lightning are really 

 not more commonly noticed than they seem to have been, when W6 

 call to mind the observation of Sir Charles Lyell, that " it is probable 

 a moment never passes without a flash of lightning striking some part 

 of the earth."* 



In London, the reader may see fulgurites in the Museum of the 

 Geological Society, including specimens from Drigg, from the shores of 

 La Plata, and from Dresden, In the Museum of Practical Geology, 

 Jermyn Street, are specimens from Natal, many of them larger in 

 size than those from Drigg, as also a tray of small ones. The British 

 Museum contains fulgurites from the Tuarie country, Africa ; from 

 the vicinity of Dresden ; from the Senner Heide, Westphalia ; and 

 from Drigg. 



Some of those from Africa are dark in colour, and more nearly 

 resemble those I have seen in a fossil state. The fine state of pre- 

 servation of most of these has been owing, no doubt, to the soft and 

 dry character of the sand around them. 



The evidences of the power of atmospheric electricity are at times 

 made fearfully manifest during thunder-storms, when the electric fluid 

 shatters rocks and scatters immense fragments to considerable dis- 

 tances, splitting and tearing up trees, levelling houses, Assuring thick 

 walls, and melting substances which have been looked upon as infusible. 

 Of the last, we have an illustration according to Saussure in the slaty 

 hornblende on the Dome du Goute, one of the summits of Mont 

 Blanc ; he found in 1787 vitreous blackish beads, of the size of hemp- 

 seed, which were attributed most clearly to the effects of lightning. 

 Ramond observed the entire face of certain rocks on several summits 

 of the Pyrenees, especially the Pic du Midi and Mont Perdu (the 

 latter upwards of 11,000 feet high), and also the rock Sanadoire, in 

 the Puy de Dome, varnished with a coating of enamel, and covered 

 with vitreous beads, of the size of peas, the result of the s^me cause ; 

 the interior of the rock being found quite unchanged. On the summit 

 of the Pico del Frayle, the highest pinnacle of the Volcano of Toluca, 



* Principles of Geology, 8th edition. 



q2 



