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Full text of "Maps can be liars! / Arthur Ballard"

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HAPS CAN BE LIARS I 



Arthur Ballard 
December 9, 1943 



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■1- 



ODTLIHE 



I. The globe as a map. 

A. The only true picture of the earth. 

B. The disadvantages of the globe. 

C. Desirability of flat maps. 

II. Methods of obtaining a flat map. 

A. Llercator's projection. 

1. Distortion of area and distance. 

B. Other projections. 
1. Fallacies. 

III. Depiction of the eerth in the same posit ion < 

A. The aviator's view of the earth. 

B. Other odd views . 

IV. The quest for better maps. 



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THE GL03E . The only true representation of the earth's surface is a globe. 

A globe is not, however, the most desirable in other respects. To 
be accurate in detail, it inust necessarily be very large. It has been estimated 
that a globe constructed on a scale of 15 miles to the inch would be neerly 
40 feet in diameter* Even the smaller globes are cumbersome snd expensive, and 
cannot be easily marked upon. Moreover, only a ->ortion the p;lobe can be viewed 
at a time. In order that the engineer, the navigator, and the military strate- 
gist be able to jnei-sure distances and plot positions conveniently, maps must 
be printed on flat surfaces. 

Various schemes have been devised to obtain a plane represents t ion 
of the earth, but all of tr ; em contain inherent errors. The brsic cause for 
this is that you simr;ly cannot make an orange peel lie flat and still keep it 
in one piece. i 

OBTAIN EC 1 I. FLAT VAP. One map with which almost everyone is familiar is the 
rectangular map of the world known as L'ercator's projection. It has been used 
since the 16th century, particularly as a navigation map. Figure 1 shows how it 
is produced. 




— i 1 ■ 

1 

5 
_= . . 



Pig. 1 



1 "Global Map Supplement." Washington Star, September 21, 1S42 , 



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Imagine that the earth is a hollow glass sphere, the land being 
painted black and the water left clear. Now suppose a cylinder of paper coated 
-with a material sensitive to light is -laced tangent to the earth, and a light 
placed at the center of the earth. The shadows of the earth's features will be 
projected upon the paper cylinder, which, upon being unrolled, will be a map 
of the earth. Near the poles the light rays have been assumed to bend, in order 
that they do not run off the map. The extreme polar regions cannot be shown 
at all. 2 

The main fallacies of this map are apparent from its construction. 
Although it is accurate in the neighborhood of the equator, it becomes increas- 
ingly distorted as one approaches the poles. Particularly noticeable is the 
distortion of areas in the polar regions. Greenland appears to be larger than 

the United States, while actually it is less 
than one-third as great. Alaska seems to 
contain at least one-half the area of the 
Unites States; in reality, the ratio is 
closer to one-fifth. 

In Kercator's projection, the 
shortest distance between two points would 
seem to be a straight line. The real mini- 
mum distance will appear as a curved line, 
the projection of a great circle. This fact 
expleins some startling statements, such as: 

The shortest route from San Francisco to 
Fig. 2 

Singapore passes through Alaska > Detroit and other -mid-western cities are 
closer to Russia than any of our seaports. 3 




PARALLEL meridians on Mercator 
projection make it comparatively 
easy to draw but result in exaggerations 
at the poles. Above, Alaska and the 
U, 5. as they appear on the Mercator 
projection; below in true proportion. 




- "illlam Alexander and ■• . J. D. Allan. The Observer 's Handbook on 
Ka£S_, Charts and Proje ct ions t London 1940, 56-62. 

3 

How Oar World is Changing Shape." Reader 's Digest , Feb., 1943, 88-92, 



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Other methods of flattening the eprth's surface employ a tangent 
plane, a tangent cone, or a series of tangent cones. A moment of reflection 
will show that they, too, are accurate only near the points of tangency. 
Although some of them show marked improvement over '.'ercator's projection, the 
distortion of distance, erea, and shape are still present. 
DEPICT I OK OF J_KE EtKTK £_ J_i_ S/M3 POSIT IP S. Too many maps always depict the 

earth's features in the same position. Figure 3 
is not readily recognisable as the United States 
because most are used to seeing it right side 
up. Yet, this is how it looks from the north 
pole . 

The advent of the airplane particularly 
Fig. 3 has rendered useless the conventional maps of 

the earth. The unusual map 



in figure 4 is an aviator's 
view of the world. Conti- 
nents and oceans are no 
longer important $ airplanes 
soar over thorn both with 
equal ease. Only the names 
and locations of places 
concern him. By taking the 
most direct routes, olanes 
have been able to cut thou- 
ands of miles off of trans- 
port shipping distances. 4 

Fig. 4 




'How Our fforld is Changing Shape." Reader's Sjgeet, Feb, 1942, 88-S2 , 



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T HE CJJEST FOR BETTER YAPS . The present day world has discovered that the maps 
It has been using for so long a time, are liars. They are inaccurate and worse, 
misleading* Every effort is now being made to obtain more adequate and precise 
maps of the world. It is hoped that the maps of the future will depict the 
earth as it really is, and that they will be used to their fullest advantage. 



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BIBLIOOiAPHY 



"Global Map Supplement." Washington Star , September 21, 1942. 
"How Our World is Changing Shape." Reader 's^ digest , February, 1945, 88-92. 
iVilliam Alexander and H# J. S. Allan. The Observer 's Handbook on Maps , Cha rt s 
and Projections , London, 1940, 56-62.