502 Hidden and Washington—Contributions to Mineralogy. 
ruby-red crystals, they were of an iron-black color, and bril- 
liant submetallic lustre. They had, usually, the basal pinacoid 
prominent and well polished; s(111,1) and e (101, 1-2) were 
also prominent. The annexed figure shows the most interest- 
ing form, observed in two crystals, on which three of the new 
planes occur. The planes identified were as follows: 
Pinacoid, ¢(001,0), prisms, a (100, 2-2), m (110, Z), 7(810, 7-3), 
dome, e (101, 1-2), pyramids a*(227, 2), B*(112, 3) 0*(223, 2), 
s(111, 1), 7*(441, 4), ¢ (818, 1-3), z (821, 3-3) and 7*(989, 1-2). 
Those marked with an asterisk are new to the species. As 
a fundamental angle cas (001,111) was taken, giving as a mean 
of fifteen closely agreeing measurements, 
I 
eas (001 , 111)==42° 207 8" .°. a: c==1: 07644252, 
Miller* giving 
! 
€~8(001 ~111)=42° 197 58" .-. a: c=1: 0°644179. 
The new planes of the unit pyramidal series were determined 
by their angles on c(001, O). The agreement between the ob- 
served and calculated angles is as follows: 
Cale. Observed. 
CACY OO 221 == T4354 142364 
caB, 001.112 = 24° 29) 24° 304/ 
CO.) 0014223) == 3121164 Bike Wee 
cat, 001.444 = 74° 397 75° (approx.) 
The new plane 7(989, 1-2) was observed on several crystals 
replacing the edge s/e (111/101). It furnished the following 
angles : 
Cale. Observed. 
SY, (111. 989)= 2° 427 io Fe 
én, (101 . 989)==25° 44’ 25° 29° 
Some of the best observed angles are here tabulated, with the 
corresponding calculated angles, from the fundamental angles 
above. 
Cale. Observed. 
CAS a0 Olli cel alae 42 aS A220 SE 
cae, 001,101 = 32° 474’ 32a 4e 
CAN 100M SMS i—— a 34a, Bos 
Sie, hl SLO 2857262 28° 263% 
UAG Biss IOS Oe ey TO? alex 
Gru, Wil. Silby ks Dy Nome 
DRG MON 2 OI Sly oy AAS WE 
ere,” 101 , 101 = 65° 34” 65° 333’ 
ea%, 101.321 = 41° 433” 41° 427 
Of very exceptional beauty as cabinet specimens were the » 
erystals of rutile found at a depth of forty-three feet in the 
shaft, just west of the excavation which yielded the crystals 
above described. The pocket was 10X2x6 feet, and its walls 
* Phil. Mag., xvii, 268, 1840. 
