Geographical Maps and /Sailing Charts. 



265 



the page upside down and viewing the figure reflected from 

 a mirror. It is believed that the reversal of one of the hemi- 

 spheres is a feature that will not prove especially confusing to 

 those well accustomed to maps. The effectiveness of the map 

 would be much enhanced if skillfully engraved on a large scale 

 and printed in two colors, one for each hemisphere, selected so 



14 



Stereographic Map of the World. Any point on one hemisphere covers the 

 antipodal point on the other. 



as to give a pronounced and pleasing effect where overlaps of 

 land surfaces occur. Such a map, issued with a protractor, 

 would be most useful for finding out great circle tracks, and 

 making all kinds of measurements in mathematical geography. 

 Some examples will serve to indicate the uses of the map, 

 which is supposed to be accompanied by a stereographic pro- 

 tractor. The two hemispheres must be kept distinctly apart 

 in thinking of the problems, and will be designated as W.H., 

 western, and E.H., eastern, respectively. 



