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elective attraction, that the various solidsdiffused through it must soon have coalescedin various proportions according to the lawsof this attraction and the presence or proxi-mity os the ingredients, and thus have crys-tallized into different groups, which descend-ed to and were deposited on the inferiorsolid kernel of the globe In those tractsin which the siliceous, and next to it theargillaceous earth most abounded, (and suchtracts appear to have been by far the mostextensive) granite and gneiss appear to havebeen first formed, and their formation maythus be explained : Both these rocks consistof quartz, felspar and mica, in a variableproportion, but the quartz and felspar aregenerally the most copious. These stonesare themselves composed of siliceous andargillaceous particles, and particularly thefirst, principally of siliceous, the two latteradmitting also the argillaceous and a smallproportion of the calcareous, the magnesianand in some instances of the-barytic. Now ofthese earths, that should coalesce first, which

* Mr. De Luc’s opinion that stones were formed bymere deposition, is refuted by Charpentier. Saxony,P- 3°4> 3°5*

with