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from the interior, animal life and vegetation will languish andfinally become extinct. • Suclr already,,to> me appears to bethe situation of our moon. Ii evidentlyhas no atmosphere,because,, no power 'of refraction.: > It.has no .’water? on .itssurface,.because no clouds or vapours.: Its’ surface is deli-neated not, as pretended, by. seas and’continents and islands,but by deep cavities, and, hollows,:and :proportionate: eleva-tions.: All is dry—sterile—lifeless on the moon.'? But:befofeI enter any furtheri on describing the:-volcanic operations Ihave :so assiduously'attended’ to, I must introduce: myreaders :to' my well-pondered ideas on: the system of ouruniverse, without which anything!.that; l icould say on .the’ subject of volcanoes or geology, would be quite unprofitable,as much so as the minute accounts of Sir William . Hamiltonand other “naturalists,’’.concerning the'.duration and direc-tion of a certain stream of lava, the shaking’of the earth,and bubbling of the sea, &c.
, The volcanic mountain of Ischia is the only one of sogreat a height that I know of, the very summit of which isformed of tuffo, thus : evidently shewing, that the mountainhad attained its present elevation, while the waters' of thegeneral ocean were at an elevation above that summit, astuffo is lava formed by the admixture’of the ejected pumice,alumine, and other comminuted materials with the waters thatcovered the eruption. I have climbed up to the topmost peakof Ischia, which is a ridge of tuffo like a sloping hog’s back,originally having been; a portion of the side of a crater, thegreater part of which was subsequently overthrown. Pre-viously to the eruptions of Vesuvius being confined to thecrater of the present cone, the extent of the preceding crateris clearly defined by a segment of it yet left standing. Thisis so considerable as to have been honoured with a name ofits own, and it is called Mount Somma . Every appearance