PHYSIOGRAPHY. GLASS II. 



the ironstone beds of Arendal in -Norway, and in the beds 

 of copper-ore in the Bannat of Temeswar. 



9- HEMI-PRISMATIC KOUPHONE-SPAR. 



Prismatoidal Zeolite or Stilbite (in part. Foliated Zeo- 

 lite). JAM. Syst. Vol. I. p. 378. Henri-prismatic 

 Zeolite. Man. p. 150. Heulandite. PHILLIPS, p. 38. 

 Blatterzeolith. WERN. Hoffm. H. B. II. 1. S. 240. 

 Bltittriger Stilbit. HAUSM. II. S. 573. Stilbit (in 

 part). LEONH. S. 445. Stilbite (in part). HAUY. 

 Traite', T. III. p. 161. Tabl. comp. p. 48. TraiteV 

 2de Ed. T. III. p. 155. 

 BROOKE. Edin. Phil. Journ. Vol. VI. p. 112. 



Fundamental form. Scalene four-sided pyramid. 

 Vol. I. Fig. 41. 



Char, of Comb. Hemi-prismatic. The relations 

 among the simple forms not being yet ascertain- 

 ed with sufficient exactness, the 50th Figure 

 may serve as a point of comparison for such va- 

 rieties as may be found in nature. 



The following are approximate measurements nearly 

 agreeing with Mr BROOKE'S, expressed in round num- 

 bers : 



s on T f = 114 0', u on u = 146 40', 



s on s f = 129 40', z on z = 136 0', 



s'on T =116 20', x on x = 95 0', 



x being two faces, which replace the edges between M and 

 T, so as to produce an edge with w, which is parallel to that 

 between u and s. Generally several crystals, very little 

 divergent, are grown the one upon the other, in such a 

 manner that the centres of M are deeper than its margins, 

 which prevents them very frequently from being measured 

 by means of the reflective goniometer. 



Cleavage, M, highly perfect. Fracture imperfect 

 eonchoidal, uneven. Surface of all the forms 



