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and a high south-west wind. The cliffs near Charmouth, in the 

 western part of Dorsetshire, presently after this alteration of the 

 atmosphere, began to smoke, and soon after they burned, with a 

 visible, though subtile flame, for several days successively; and 

 continued to smoke, and sometimes to burn, at intervals, till the 

 approach of winter ; nay, ever since that time, especially after any 

 great fall of rain, thunder and lightning, or a high south-west wind 

 (which drives the sea with great violence against the cliffs, and beats 

 off large pieces of them), the cliffs continue to smoke, and some- 

 times to burn with a visible flame, which, during the summer months, 

 is frequently observed in the night-time. On examining these cliffs, 

 in the year 1759> I discovered/' he says, " a great quantity of 

 pyrites, not in any regular strata, but interspersed in large masses 

 through the earth, and which proved to be martial ; of cornua am- 

 monis of different sizes, and other shells, but of the bivalve class, 

 which were covered over, and mineralized,as it were,with the pyritical 

 matter ; of belemnites, also crusted over with the like substance : 

 and the cliffs, for nearly two miles long, and from the surface to 

 thirty-five or forty feet deep, even to the rocks at high-water mark, 

 were one bed of a dark-coloured loam, strongly charged with bitu- 

 men. Moreover, I found also, he says, a dark-coloured substance, 

 resembling coal cinder ; some of which being powdered, and washed 

 in distilled rain-water, upon filtrating the water, and evaporating it 

 to a pellicle, its salts shot into fine crystals, and appeared to be no 

 more than a martial vitriol ; one ounce of this cinder-like substance 

 yielding one drachm of salt. I gathered up about one hundred 

 pounds weight of the different kinds of those pyrites, marcasites, 

 &c. which were laid up in a heap, exposed to the air, and every day 

 sprinkled with water : the consequence was, that, in about ten days 

 time, they grew hot, soon after caught fire, burned for several hours, 

 and fell into dust. 



