Lava Vesuvius between May 14 and June 4, 1737. Serao described "a flow of fiery lava" as an analogy to the flow of water and mud down the flanks of the volcano following heavy rain. The composition of almost all lava of the Earth's crust is dominated by silicate minerals, mostly feldspars, olivine, pyroxenes, amphiboles, micas and quartz. Igneous rocks, which form lava flows when erupted, can be classified into three chemical types: "felsic", "intermediate", and "mafic" (four if one includes the super-heated "ultramafic"). These classes are primarily chemical, however, the chemistry of lava also tends to correlate with the magma
Substance theory of process. Roman Catholic theologian Karl Rahner, as part of his critique of transubstantiation, rejected substance theory and instead proposed the doctrine of "transfinalization", which he felt was more attuned to modern philosophy. However, this doctrine was rejected by Pope Paul VI in his encyclical "Mysterium fidei". In direct opposition to substance theory is bundle theory, whose most basic premise is that all concrete particulars are merely constructions or 'bundles' of attributes or qualitative properties: The bundle theorist's principal objections to substance theory concern the bare particulars of a substance, which substance theory considers independently of the substance's properties. The