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vegetable matters, of which it is so evidently composed. The dis- 
tinctness of vegetable form and structure, which is thus displayed, and 
which incontestibly proves their previous existence in this mass, serves 
also to refute the opinion, promulgated by Pliny, and adopted by 
Schoockius and others, of this substance being entirely of mineral 
origin ; and of its being originally formed in its present situations. 
Those who have endeavoured to account for the formation of peat, 
by the sinking of large floating islands, which have afterwards be- 
come covered by the accumulation of strata of other earth, appear, 
certainly, to have mistaken the cause for the effect. This will, I 
think, appear sufficiently plain, by examining the following very cu- 
rious account of the appearance of these islands, as well as of the 
phenomena which precede and accompany their formation, as given 
by a gentleman who appears to have almost witnessed the separation 
of these floating islands in the lake of Derwentwater. 
The lake of Derwentwater is celebrated for the astonishing phe- 
nomena its waters exhibit. At uncertain times the waters of this 
lake experience very considerable agitations, the waves running to 
a great height, and forming large white breakers, on which the 
boats are tossed as though in a severe storm ; whilst none of the 
usual causes of such commotions of water are discoverable. The 
waves differ from those produced by ordinary causes; not rolling 
along from one end of the lake to the other ; but rising, in mourn 
tainous heaps, from ten inches to two feet in height; as though 
raised by some powerful elevating force, applied underneath ; and, 
in agreement with the idea thus suggested, the people of the neigh- 
bourhood term this phenomenon a hottom wind. Sometimes the 
whole surface of the lake is thus agitated, at other times it is only 
partially affected ; and frequently it will strike a boat with so much 
force, that it will appear as though it had struck against a rock : a 
very considerable roaring noise often accompanying these surprising 
appearances. 
