32 PRIMITIVE FORM OF CRYSTALS. 



of the fissure ; but, on the other hand, where the native copper 

 was in quantity in the closed cavities, surrounded by quartz, 

 scarcely could we find more than partial traces of the oxid- 

 ized copper; the other parts of the cavities were rilled with 

 water, and saponaceous matter resembling silex. 



The practical researches of Rome de Lisle and j4bbe Hauy 

 have done much in ascertaining the external forms of 

 crystals : the latter had assumed the existence of six primitive 

 forms, from the combination of which he supposed the 

 secondary crystals may be produced ; he finally reduced them 

 to three, as before observed. First, the tetrahedron ; second, 

 the simple prism ; third, the cube. These appear to be the 

 ultimate forms assumed in a compressed solidified state ; but 

 the original must have been the spherical, assuming the sphe- 

 roidical and ellipsoidical shape, according to the nature of the 

 compound molecule, and resolving itself into the tetrahedron, 

 the simple prism, or the cube, according to the diversity of tin? 

 compound. Dr. Wollaston has assumed the primary molecules 

 to be the sphere, the spheroid, and oblong sphere, or ellipsoid. 



The extraordinary and beautiful parallel between the chro- 

 matic series of colors and the diatonic system of the musician, 

 with their several relations, accordances, and coincidences, so 

 ably described by Mr. Field so far back as 1819-20, in his 

 " Esthetics, or the Analogy of the sensible Sciences," is worthy 

 of the deepest attention, as well from the admirable facts in 

 which it abounds, as from the body of profound and logical 

 reasoning, in his own peculiar felicitous style, displaying the 

 erudite and accomplished philosopher, and the inexhaustible 

 powers of a comprehensive mind. 



This parallel between color and sound corresponds in a 

 remarkable manner with another the tones afforded by glasses, 

 and the radii exhibited on the surfaces of the water with which 

 they have been attuned, as described by Mr. Goldsworthy 

 Gurney in " a course of lectures on chemical science delivered 

 at the Surrey Institution, arid published by Whittaker in 



