1888. | of Curves and of Surfaces. 243 
The groups (B) and (C) could be treated in the same manner, and 
thus we should obtain 
Nieget eaete eae eta eae h eh 
h, oy h,0z h, 0a h, oy h,oz h, ox)’ 
Atty eo ea 
h, 02  h, ox h, oy h, 02 non ioy\ 
feet ean! ea at te ea 
h, 0x h, oy hoz h, ox h, oy h, oz 
These equations imply 
Vege on\ w Le/CENS Vi 7OG\] Pl /en\70, L (0EN 
iz lag) — Halos) ~ 2 Ge) ~ i Ge) ~ ae ae) ~ He lGy): 
which may be readily verified from the equations at the com- 
mencement of Art. 9. They also yield the relations 
l A m n 
10n 1 0€ 
non alae; mmlnce: 
h, 0a 
h,o 
| 
ice Beh 
h, oy h, oz 
Further, we ha ve 
0z 
Aisle) - 
hoz h, ex 
1 — 
0€\” 
I ie (a) mie 
_,{1an_ 108 
) (ee hoy 
iL 
h, 
il 
Now 
Gn 1 cz 
h, 0a h, oy 
1 d€ 0£ 
1 0&0n 1 Onodn 
hh, Ou 0x 
1 af a¢ an Of 
~ Jah, 02 Da * he dy dz 
eG 
* ih, 2a - 
au i 0g | Lom 
h, oy h, oz 
1 0& On 
hh, 0a Oz 
1 On 
trae 
+ 
us halves 
~ (h, Oy 
1 On 
eae 
eee 
1 
h, du * h, dy * 
h,? oy 02 
1 abo 
hh, 0x Oy 
i | emus 
h,0z)  h, oy 
Ln, 1 abd 
hh, Oy 0x 
1a , 1 
h, 02)’ 
hihi, Oy Oy 
0g 
ox h, oy 
