wn
from the head of Lochrannoch, one towards Inverness and the other to
Stonehaven. The united line of the different rivers which were flooded,
could not be less than from five to six hundred miles in length; and the
whole of their courses were marked by the destruction of bridges, roads,
crops, and buildings. Sir T. D. Lauder has recorded the destruction of
thirty-eight bridges, and the entire obliteration of a great number of
farms and hamlets. On the Nairn, a fragment of sandstone, fourteen feet
long by three feet wide and one foot thick, was carried above 200 yards
down the river. Some new ravines were formed on the sides of mountains
where no streams had previously flowed, and ancient river-channels,
which had never been filled from time immemorial, gave passage to a
copious flood.[270]

The bridge over the Dee at Ballater consisted of five arches, having
upon the whole a water-way of 260 feet. The bed of the river, on which
the piers rested, was composed of rolled pieces of granite and gneiss.
The bridge was built of granite, and had stood uninjured for twenty
years; but the different parts were swept away in succession by the
flood, and the whole mass of masonry disappeared in the bed of the
river. "The river Don," observes Mr. Farquharson, in his account of the
inundations, "has upon my own premises forced a mass of four or five
hundred tons of stones, many of them two or three hundred pounds'
weight, up an inclined plane, rising six feet in eight or ten yards, and
left them in a rectangular heap, about three feet deep on a flat
ground:--the heap ends abruptly at its lower extremity."[271]

The power even of a small rivulet, when swollen by rain, in removing
heavy bodies, was exemplified in August, 1827, in the College, a small
stream which flows at a slight declivity from the eastern watershed of
the Cheviot Hills. Several thousand tons' weight of gravel and sand were
transported to the plain of the Till, and a bridge, then in progress of
building, was carried away, some of the arch-stones of which, weighing
from half to three quarters of a ton each, were propelled two miles down
the rivulet. On the same occasion, the current tore away from the
abutment of a mill-dam a large block of greenstone-porphyry, weighing
nearly two tons, and transported it to the distance of a quarter of a
mile. Instances are related as occurring repeatedly, in which from one
to three thousand tons of gravel are, in like manner, remov