3.  There are numerous perpendicular fissures in the rocks of Derbyshire, in which the ores of lead and copper are found, and which pass to unknown depths; and might thence afford a passage to steam from great subterraneous fires.

4.  If these waters were heated by the decomposition of pyrites, there would be some chalybeate taste or sulphureous smell in them.  See note in part 1. on the existence of central fires.]

        Impetuous steams in spiral colums rise
        Through rifted rocks, impatient for the skies;
        Or o’er bright seas of bubbling lavas blow,
180 As heave and toss the billowy fires below;
        Condensed on high, in wandering rills they glide
        From Maffon’s dome, and burst his sparry side;
        Round his grey towers, and down his fringed walls,
        From cliff to cliff, the liquid treasure falls;
185 In beds of stalactite, bright ores among,
        O’er corals, shells, and crystals, winds along;
        Crusts the green mosses, and the tangled wood,
        And sparkling plunges to its parent flood. 
        —­O’er the warm wave a smiling youth presides,
190 Attunes its murmurs, its meanders guides,

        (The blooming FUCUS), in her sparry coves
        To amorous Echo sings his secret loves,
        Bathes his fair forehead in the misty stream,
        And with sweet breath perfumes the rising steam.
195 —­So, erst, an Angel o’er Bethesda’s springs,
        Each morn descending, shook his dewy wings;
        And as his bright translucent form He laves,
        Salubrious powers enrich the troubled waves.

[Fucus.l. 191.  Clandestine marriage.  A species of Fucus, or of Conserva, soon appears in all basons which contain water.  Dr. Priestley found that great quantities of pure dephlogisticated air were given up in water at the points of this vegetable, particularly in the sunshine, and that hence it contributed to preserve the water in reservoirs from becoming putrid.  The minute divisions of the leaves of subaquatic plants, as mentioned in the note on Trapa, and of the gills of fish, seem to serve another purpose besides that of increasing their surface, which has not, I believe, been attended to, and that is to facilitate the separation of the air, which is mechanically mixed or chemically dissolved in water by their points or edges; this appears on immersing a dry hairy leaf in water fresh from a pump; innumerable globules like quicksilver appear on almost every point; for the extremities of these points attract the particles of water less forcibly than those particles attract each other; hence the contained air, whose elasticity was but just balanced by the attractive power of the surrounding particles of water to each other, finds at the point of each fibre a place where the resistance to its expansion is less; and in consequence it there expands, and becomes a bubble of air.  It is easy to foresee