72 Crystallographic Examination of Eremite. 
planes é and é€ replacing respectively the obtuse and acute terminal 
edges; e and e’ each rectangular terminal edge ; a and o the obtuse 
or acute solid angles, according as the mark — or ~ is placed over the 
letter; and e,e’ replacing the lateral edges. 
For the determination of the descriptive expressions of the crys- 
tal, (in which I employ Naumann’s system of notation,) the planes @ 
may be assumed as faces of the positive fundamental hemipyramid. 
The following descriptions are thence deduced for the crystals: _ 
'Fig.1. oPo.aP’o.eP.Po.P.P’0.2P’o.—P. —Po. 
M Pe ened tua ce e/ eaiti'® 
Fig. 2. oPa.aP/o.a@P. oP2.Po.P.2P’2.P’o .2P’o. 
M P CN OU He Paes HO Ne e/ 
—P.—Po. ‘ 
ERM 
Fig. 3. oP. aP’/o.Po.2P2.2P’2.P’o.-2P/2.—2P2. 
M Biaee i) OU. ee 0! 7) 
Pe. 
é 
The angles assumed as the basis of the calculations are as fol- 
low : 
: €=140° 40’, M : e=126° 8’, M : e=136° 35’ 
The following are the results obtained by calculation. In some 
instances the angles coincide exactly, in others very nearly, with 
those which I have obtained with the reflective goniometer. 
a:63$c=:9471 3 13 10265 
7=76° 14’.°.M ; T=108° 46 
sity WIS ey 6’: 0/(over e’)=130°39e’ ; 6/=157° 43/ 
a 
a} DT=135° 39’ 0: 0=138° 8’ € 3) 1450 6! 
at M1319 53’ 0: M=148° 12’ eh 130016! 
a $a=106° 36 0 {01299 53/ é : €(adjacent)=93°12/ 
faa Ro 0: M=141° 257 Cia Oe 
a? M=118° 13’ 0 3 O(over ec) = 70°24’ é 3 6/=130° 32’ 
eto 
: a (overe)=109°54’e ; P=131° 52’ € $ a=148° 197 
5 
pian 93° 10/ 
ry =a (e) e at O Ey ° 
0! r} o’=81 4! e/ @ P=150 50 € o — ; 86° 50’ 
Oo te 
a: To f1Oey | ee Mee ; Too eon oe MAU By 
al: M—=1900110' > es Meee es doneientes 
;M— eeeigd Co = 
0! 3 0/=67° 44/ e $ a= 148° 20/ e$a=146° 17 
o 3 T=111° 2’ e$a=141° 34 € } A2=138° 58” 
Oo + M=1099 11’ ee’ = 152° 56’ e $ Wf =155° 287 
