I 
osa 
/ 3 E’ 
\ ^ 
J ft. 
—v «4 - 
Uuianes; lie conv* ion::. 1 id vc w(!HPd ♦&* - 
>-X! ^ 
[34--r.:!f, ai ■ • si;.. via an (1 e;:,>J- a : :- i ! ■ §t- 
>me ■HHHMIBBHI 
maps, and additional futures are xil 
gs . - : '''* 1 I ■ S f S I „. f f t 
pme special ma pa 
I ' k> filter features are represented in bhu% the 
• 11 i • i j i 
•car, 
; • V? single blue lines and the u ■ 
O 
8 j|,he sea by blue water lining or blue d 
-those whose beds arc dr; for ^ 
*-* >e . 
;r?re par: of 
I 
I 
town by lines of blue dots adft dashSjj 
fbown by contour lines in brown t ,whid 
%* 
emented by shading showing tbe effe 
>e northwest across the area represented, for the 
in pose of giving the appearance of relief and thus aiding ifx 
tation of the conn lines. A cm 
i i s an imaginary line on the ground (a. con to v t,| 
Gwhidteag &t> the same altitude above sea. level. But 
’ T > at any altitude, but in practice. • tdl;'' - •or -I 
regular intervals of altitude are 
l if t the sea itself is. a contour, the datun c ei 
■ 
t level. The 20-foot contour v 
b( y e ’i \e if the sea should rise. 20 ibet. Contour Saiifes show 
he :• ill ape of thAJiills, mountains, a, a. a valleys; as 
Successive contour lines.. Uiat are far 
a 
i * 
1 i(li 
n r 
.1 
a s 
o 
>e 
lies .that run togetj 
£* l 
nc 
v y 
a c 
• Ck 
manner in 
- - #y 
lines 
k> 
Ct- 
term, 
