45 
gested. If only a variety of O. obtusa, I would propose for it the name of Otop- 
teris obtusa, variety densa. 
Major Austin then proceeded to make some observations on the remark- 
able effects produced by lightning. 
As far back in time as June 17th, 1839, a vivid stream of electric light was seen 
to descend from a dense dark cloud and strike the green turf in the park of Mrs. 
Carden, in the county of Cheshire. When the thunder-storm had abated, the 
spot where the lightning flash had struck was examined, and the effeets produced 
by the electric current presented some interesting and curious phenomena. 
In a circle about twelve or thirteen inches in diameter the grass was scorched 
and shrivelled up as though it had been dead for many years. On removing the 
brown and withered turf, which was a mere superficial skin of vegetable mould 
resting on a rock of new red sandstone, it was found that the electric current had 
penetrated the hard sandstone to a depth of three quarters of an inch, and then 
became deflected and divided into several smaller streams, which radiated from the 
central point of contact. Not only had the lightning-flash penetrated right through 
the greensward and into the hard siliceous sandstone, which it shivered into 
minute fragments, but it had then separated into several diverging streams, which 
as they passed along, and through the shivered pieces of rock, converted portions 
of it into small tubes several inches in length, and about half an inch in diameter, 
the interiors of which were completely vitrified, as may be seen in the specimen on 
the table, for which I am indebted to my friend Dr. Baird, 
These phenomena show the wonderful penetrating power of electricity, and also 
prove the extraordinary heat accompanying it, for in this case it was, at the 
moment of contact with the sandstone rock, sufficiently powerful to convert a hard 
siliceous material into a number of glazed tubes. 
In Sir Charles Lyell's Principles of Geology, reference is made to Dr. Hibbert's 
work, in which the latter, quoting from the manuscripts of the Rev. George Low, 
of Fetlar, one of the more northern Shetland Islands, proves that electricity is a 
powerful agent in producing havoc and ruin among rock masses. The facts, as 
taken from Mr. Low's manuscripts, are as follows : — At Funzie, in Fetlar, in the 
middle of last century, a flash of lightning in a moment tore from its bed a rock 
of mica-schist 105 feet long, upwards of ten feet broad, and in its thickest part 
from four to five feet. Such was the force of the stroke, that it not only detached 
the mass from its position, but broke it into three large pieces, besides shivering 
portions into numerous smaller fragments. One of the larger pieces, twenty-six 
feet long, ten feet broad, and four feet in thickness, was completely turned over. 
Another piece, 28 feet long, and five feet in thickness, was thrown across an elevated 
point to the distance of fifty yards. A third disjointed mass, between thirty and 
forty feet long, was hurled still further in the same direction, until it fell into 
the sea. 
Major Austin also exhibited and described a portion of a Caligurite found 
in Cheshire. 
