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tural purposes ; near this spot there is a narrow rivulet which runs down the 
valley from Clonshara- Some years since this small stream, after an unusual fall 
of rain, broke down its western bank and cut a new channel through the sandy 
flat, where it laid bare a number of trees with all their branches as complete as 
when growing erect, but which were lying prostrate on a bed of clay below the 
sand. How the trees became felled it is not easy to determine, unless we suppose 
that a hurricane had devastated the coast and had by its violence uprooted the 
trees, and at the same time driven a deluge of sand from the adjacent shore, and 
thus buried the roots, trunks, branches and all. That the trees were speedily 
covered up can hardly be doubted, for if they had been left exposed to the atmos- 
phere for any length of time the small twigs would in all probability have been 
removed. It is worthy of remark that no description of trees are now growing 
in the vicinity of the place, and that in the adjoining bog of Kilbride, oak trees, 
hazel nuts and wood, are found buried in the peat in abundance. Specimens of 
the black oak, hazel wood and nuts, were exhibited. 
If we extend our enquiries to Africa it will be found that the sands of the 
Lybian desert have been driven by westerly winds till they have left no land fit 
for tillage on the western banks of the Nile, unless where protected by elevated 
ground ; and were it not for the ridge of mountains known as the Lybian chain, 
which extends some distance from, and along, the left bank of the river, and in 
part forms a barrier against the invasion of the desert sands, the shores of the 
Nile, on that side, would cease to be habitable. Few persons reflect on the im- 
portant part sand performs in producing modifications on the globe. In Egypt 
the traveller may walk over villages now lying beneath the sand, or stumble over 
the tops of minarets, and mark the sites where proud cities once flourished, but 
where all is now a barren wilderness — a silent solitude. 
The banks formed across the mouths of small rivers, on the eastern shores 
of England and Ireland are caused by the tidal currents passing along the coast. 
These currents bear in their course the materials washed from the cliffs, and sea 
margins generally, and when any obstacle is sufficient to impede and lessen their 
velocity, such as a river pouring its water into the ocean, the matter held in sus- 
pension sinks to the bottom, and a bar is formed in consequence. In this way 
the mouths of estuaries and rivers have been diverted several miles from their 
original courses. Two or three instances will be sufficient to illustrate this. Take 
for example the Norfolk rivers Aide and Yare, which have their outlets further 
south than formerly, the first named being transferred to a point ten miles distant 
and the other to about four miles. On the eastern coast of Ireland the same 
operation is in progress, a carefully measured plan of one of these alterations, the 
Murragh bank and river Vartray, county of Wicklow, I have here. This bank is 
chiefly composed of shingles mingled with sand, but the progress by which it has 
been formed is precisely the same as that which produces the simple sand bank. 
Its length is nearly three miles. * 
From careful observations it has been proved that the rivers on the eastern 
coasts of the British Islands are continually deflected southwards. The cause of 
this has been well ascertained, and is as follows : — When the great tidal wave from 
