598 SUPPLEMENTARY NOTES. 
of Genesis, and that later creation, of which an account is 
given in the third and following verses, and which has especial 
relation to the preparation of the Earth for the abode of man. 
At p. 24, it is shewn in a Note by Prof. Pusey, that the notion 
of such a prior act of creation was entertained by many of the 
Fathers of the Church, and also by Luther. 
P. 41. Professor Kersten has found distinctly formed crystals 
of prismatic Felspar on the walls of a furnace in which Copper 
slate and Copper Ores had been melted. Among these pyro- 
chemically formed crystals, some were simple, others twin. 
They are composed of Silica, Alumina, and Potash. This dis- 
covery is very important, in a geological point of view, from its 
bearing on the theory of the igneous origin of crystalline rocks, 
in which Felspar is usually so large an ingredient. Hitherto 
every attempt to make felspar crystals by artificial means has 
failed. See Poggendorf's Annalen, No. 22, 1834, and Jameson's 
Edin. New Phil. Journal. 
Professor Mitscherlich has also succeeded in producing syn- 
thetically, by the action of Heat, artificial crystals of Mica ; these 
are difficult to make, unless the ingredients pass very slowly 
from a fluid to a solid state ; as they are supposed to have done, 
in an infinitely greater degree, in the formation of Granite, and 
other Primary Rocks, of which Mica forms a large ingredient. 
In more recent igneous rocks of the Trap formation, in which 
Mica is rare, and crystals of Pyroxene abound, it is probable that 
the cooling process was much more rapid, than in rocks of the 
Granitic series ; and crystals of Pyroxene have been formed syn- 
thetically by Mitscherlich, from their melted elements, under much 
more rapid cooling than is required to produce artificial Mica. 
The experiments of Sir James Hall, on whinstone and lava, 
made in 1798, first shewed the effects of slow and gradual cool- 
ing in reproducing bodies of this kind in a crystalline state. 
Similar experiments were repeated on a larger scale, by Mr. 
Gregory Watt, in 1804. Sir James Hall's experiments on re- 
producing artificial limestone and crystalline marble, were made 
in 1805. 
Mr. Whewell, in his Report on Mineralogy to the British Asso- 
