B. W. Frazier—Axinite from Bethlehem, Penn. 443 



axis, that of the zone p, m, r, as macrodiagonal axis, and that 

 of the zone y, m, b, as brach yd i agonal axis. This position has 

 been chosen to facilitate the comparison with datolite, which 

 will be made in this paper. 



New planes were observed on some of the crystals, but un- 

 v their nature was not such as to admit of measure- 

 ments sufficiently accurate for their determination. 



In examining these crystals I have been struck with the 

 ice between them and crystals of datolite, which I 

 will now endeavor to make manifest. If we take for the 

 cryatallographic axes of axinite those adopted in the figures, 

 and choose I for the fundamental, right hemi-prism and z for 

 the upper hemi-macrodome, If, the other planes will have the 

 parameters given in the first column of table II. In this table 

 all the forms, hitherto published as definitely established, are 

 u'lveii with their parameters in this new position, and, for con- 

 venience of reference, with their parameters in the positions 

 Mill ■■ X:mm mn. IVsCio ze,ux. Sehrauf and v. 

 Rath. ' 



The values for this new position, of the angles between the 

 axes and between the axial planes and of the lengths of the 

 axes, as calculated from the measurements of v. Rath, are the 



i the position adopted 



ial lengths of 



lolinite criterion is furnished by a comparison of the angles 

 >etween similar planes. To facilitate such a comparison I 

 >ave Kepmvd table III. Under the column headed datolite, 

 he letters and angles are those given bv E. S. Dana in his 

 n-tiele on the crystallization of datolite in Tschermak's Min. 

 >Iitt., 1>i74, No. 1. As for each hemi-pyramid, prism and 



ng fo^raTin the r Mgles™ffSie 



txial planes, I have added a second column of angles under 



