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this been accomplished. If, however, we still want actual 
evidence of what a comparatively small current can produce 
in one hour, we have only to refer to the effects of the 
Holmfirth flood, in February, 1852. The materials swept 
from the reservoir when it burst were supposed to weigh 
about 50,000 tons. The reservoir was not more than a 
quarter of a mile in length, with a surface of eleven acres, 
and contained about 86,248,000 gallons of water, yet the tor- 
rent tore up the sides of the valley in some places to a depth 
of 10 to 20 feet, and covered the meadows with fragments of 
rock, sand, and gravel for a considerable distance. Amongst 
the comparatively small masses, however, scattered about, 
there were three or four blocks of stone which deserve to be 
recorded, — the first, a mass 7 feet in length by 5 feet in 
breadth and 2 feet in depth, and weighing 5 or 6 tons, was 
transported half-a-mile ; another, 12 feet by 6J- feet, and 
2 feet deep, and weighing 7 or 8 tons ; and lastly, in the 
middle of the valley, near Upper Digley Mill, about one- 
third of a mile from the parent rock, was a block 22 feet 
long, 6 feet broad, and feet thick, and weighing about 
20 tons. If, then, such were the effects of a temporary flood, 
caused by a body of water comparatively so small, and along 
a valley where its force could not be maintained, we may easily 
form some conception of the enormous power which a more 
continuous flood, with more sustained action, would possess. 
But what are all these, however large we may consider them, 
compared with many which are still lying on the precipitous 
sides of the mountains in Switzerland? One block of granite 
behind Neufchatel, 850 feet above the lake, measures between 
50 and 60 feet in length, by 20 feet in breadth, and 40 feet in 
height. Another, in the Canton of Berne, measures 61,000 
cubic feet. The largest boulder I have seen turned up 
during the recent excavations, is one lying near Larchfield 
Foundry, in Hunslet-lane, about a yard long and nearly two 
feet broad. 
