Mr. WHeweE tu on the Classification 
SQUARE-PYRAMIDAL SYSTEM. 
Remarks. Example and Figure. Class. 
Class II. 
: No. 6. 
Sq. Pyr'. Titan-ore 
Mohs, Vol. II. 100. Hobs e 
$593 
7S 
P+n,(P+n—3)', &c. 2Qr,Q2| No. 7. 
of Mohs. u z |MohsII.5 
P +n, (P+n— 3), &e. 3Qr, Q2]| No.8. 
of Mohs. ; v» z_ |MobhsII.6. 
These are included by | Sq. Pyr’. Garnet No. 9. 
Mohs in the preceding com- II. 96. 2Q, Q2 | MohsII.7. 
bination, because he derives bce 
Q 2 from Qr. 4Q, 2Q2 
re 
and 4Q, Q4 
rT 2 
Class IIT. 
From this parallelism of |Sq. Pyr. Zircon Q3,Q4,Q5} No.1. 
the edges of several pyramids IT. 99s" ee thee 
we learn that they are co- 
ordinate (i. e. g =p). 
Sq. Pyr’. Garnet 2Q2,Q2| No. 2. 
II. 96. e 
z 
z& 
Combination. 
3 PQ, pQ2 
2pQ, PQS 
3 PQ, pQ4 
generally 
1 
= PQ, pQn 
2qQr, gQ2 
3qQr,qgQ3 
4 qgQr,IQ4 
generally 
ngQr, gQn 
3qQr, gQ2 
4qQr, gQ3 
5 qgQr,qQ4 
6gQr, gQ5 
generally 
n+1qQr, gQn 
29Q,qQ2 
3qQ, gQ3 
5¢Q, qQ5 
generally . 
ngQ, gQn 
pPQm, qQn 
pQm, pQn 
pQm, qQm 
