PRINCIPLES OE GUNNERY. 
283 
make the calculation too long for ordinary purposes. The ascending 
branch will be computed in one step. 
Here 
= 31°, 0 = 0, D = 31°, 
d 3 
log - = 9*5422, V= 745, 
w 
, - tan 31° *60086 OAAylQ 
tan (p 1 = —-— — —-— — -30043; 
2 2 
^ = 16° 43', 
and p sec = 745 cos 31° sec 16° 43' = 667 f.s., 
also p = 638*6. 
q sec (px may be found by substituting in equation (i.) [note], 
/ 1000 V 
\q sec qij 
d 3 
X 31 x sec 16° 43' 
9-54655 
= 1-182 + 3-370 = 4-552, 
and q sec q> 1 = 603-4 f.s.; 
or q = 577*8. 
The correct value of q>, then, is 
/ 1000\ 3 
+ V 667 ) 
<P —<Pi + 
p — q a 
p + q 3 
_ l 6 o 43' l 639 - 578 X 31 X 60 
6 + 63 T +178 X ““8 ’ 
- 16° 43' + C \^ 20 = 16° 43' + 81' = 17° 14', 
w 
1217 
COS <p (Sq gee p S'p sec p) 
= COS 17° 14' (^03-4-^67)5 
or X= 6726 ft., 
T=X tan 17° 14'= 2086 ft,, 
to 
¥ 
= 11'06 secs. 
^603*4 — 14282 
11828 
2454 
u567 
T — 19. p6034 “ ^66?) 
^603-4 = 16-777 
^667 = 12*9 04 
3-873 
N.B.—As Table III. is not calculated below 900 f.s., it becomes necessary to make the calculation 
independently. 
d 2 
~ D see (pi = Dq sec p^ — Dp se c p^ 
180,? ( 1000)3 r pSeC ^dv 
64-4 / 
n 
q_ sec <£, 
(since IC = 64-4, and is supposed constant below 900 f.s.) 
180 x 32j2 _J_ | / 1000 \ 3 _. / 1000 \ 3 > 
64-4 1 V <2 sec pp \p sec pp S 
9-54655 x (4^) 3 ) ; 
C \q sec pp \p sec pp > 
v- 1 
37r 
^2 
/ 1000 y 
sec pp 
D sec pi 
9‘54655 
/ 1000 \ 3 
\p sec pp 
(i.) 
36 
