aiBB — A CHAPTER ON FOSSIL LIQHTNl^G. 
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twelve to eighteen inches from their roots, melted quartzose matter, 
and vitrified tubes, of a flattened form with zigzag projections. Our 
wonder is, thatsnch manifestations of tlie effects of lightning are i-cally 
not more commonly noticed than tliey seem to have been, when wo 
call to mhid 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 fi-om 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 foimd 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 same 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. 
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