“160 Scientific Intelligence. 
‘ 
It was observed that the fine emerald color characteristic of the 
erystal under examination belonged to a border 4 to #™™ in thick- 
ness ; furthermore, narrow canals hexagonal in form and made 
by planes of the unit prism, were noted running through the crys- 
tal parallel to the vertical axis. 
Monazirze.—The crystals examined were temankable for their 
size and perfection of form, and especially interesting as being 
penetration-twins cruciform in shape, with the orthopinacoid as 
the twinning plane. The chief points in regard to these erystals 
are contained in the note by Mr. Hidden in this Journal for Sep- 
tember last, p. 207. In addition to the planes given by Hidden, 
vom Rath notes 1-2 (212). As fundamental angles were taken 
001A 12=188° 7’, 010, 110=133° 8’, also the twinning angle 
1-%A 1-7=160° 4'; from these the axes were calculated 
a:b: c=0°96092 : 1: 090807 ; B=103° 264’. 
The faces did not allow, in most cases, of very accurate measure- 
ments, though on the whole the agreement with the calculated 
angles was tolerably satisfactory. A minute comparison is made 
with the crystals from other localities both as to occurring planes 
and angles. Some of the measured and calculated angles are : 
Measured. , Calculated. Measured. Calculated. 
i-4~ O 103% .297 103° 2637 1-7 ~ 2-7=160° 1’ 160° 253” 
q-t~21-4 100° 237 99° 58” 1l-¢a 1-72119° 26% 118° 4837 
oN . 1353! ° , HAV NEB LY 132° 5437 
WSU Sage iyaie 1 aly a id, 2-4==150° 40’ 151° 273” 
130° 40/ 
ApaTiITE.—Some delicate prismatic crystals (257" in length) 
showed the panes O(0001), $ (1012), 1(1011), 2(2021), 1-2(1122), 
2-2(1121), 3: 3(2131). The angles measured agreed within a 
minute or two with those of Kokscharow. 
SPopUMENE.—Some crystals, 20™™ in size, and fully developed 
at both ends except a single point of attachment, proved to be 
very different in habit from the hiddenite previously described. 
The identification of the planes was a matter of some difficulty, as 
the faces were dull and only to be measured by means of attached 
glass plates. The planes observed are given in the following list ; 
of these, z, 7, ¢, d, and @ are new. 
ee é-1); I(110), m (120, i-2), n (130, i-3), 2(150, 5); f(011, 1-2); (312, 
), @ (421, 4-2), € (241, 4- =) t (481, 8- Hy 
As fundamental angles were taken: 
Ue S864 8a wi we== Arial 3 GOP ein og 
and the axial ratio calculated is 
a=0 : c=1°1283: 1: 0°62345, B=110° 27}. 
These results agree very well with the axial ratio given by J. D. 
Dana for the Norwich crystals. The crystals showed f/ and p 
large and striated parallel to the edge of J and f,; J, 6, ¢ were 
also well developed, while the other planes were quite small. 
