[footnote] *Sir James Hall, in the 'Edin. Trans.', vol. v., p. 43, and vol.
vi., p. 71; Gregory Watt, in the 'Phil. Trans. of the Roy. Soc. of London
for' 1804, Part ii., p. 279; Dartigues and Fleurieu de Bellevue, in the
'Journal de Physique', t. lx., p. 456; Bischof, 'Warmelchre', s. 313 und 443.
In the latter case, the crystals are formed partly in cavities and partly
inclosed in the matrix. The same materials yield the most dissimilar
products, a fact that is of the greatest importance in reference to the
study of the nature of erupted rocks, and of the metamorphic action which
they occasion. Carbonate of lime, when fused under great pressure, does not
lose its carbonic acid, but becomes, when cooled, granular limestone; when
the crystallization has been effected by the dry method, saccharoidal
marble; while by the humid method, calcareous spar and aragonite and
produced, the former under a lesser degree of temperature than the latter.*
[footnote] *Gustav Rose, in Poggend., 'Annalen.' bd. xliii., s 364.
Differences of temperature
p 259
likewise modify the direction in which the different particles arrange
themselves in the act of crystallization, and also affect the form of the
crystal.*
[footnote] *On the dimorphism of sulphur, see Mitscherlich, 'Lehrbuch der
Chemie', 55-63.
Pages:
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546