Geographical Maps and Sailing Charts. 



367 



parallels of a hemisphere, either upon the plane of the equator 

 or of a meridian, would be a most excellent exercise. To pro- 

 ject the parallels and meridians for a limited area, as, for 

 example, for a map of the United States or New York State, 

 would be too difficult a task for any, except those who were 

 proficient in trigonometry and possessed some skill in draught- 

 ing. There is no reason, however, why the stereographic 

 meridians and parallels should not be engraved and printed, 

 and furnished to scholars for exercises in map drawing and 

 measurement. A prominent educator in New England, a per- 

 son of large experience, has assured the writer that there are 



30 



*3^ 



^^/^^y^^f^j • 





^^^p^J ^^T^Sf ( 



»L{ 



■ 'pTvkrCn w^l ' 



i v^ 



/yrffgj' 





i^te 







5k* 







* M 



MA 







-4 — \^iy\ )A 



Africa, Stereographic 

 Projection, from Map of 

 the Eastern Hemisphere. 



Africa, Stereographic 

 Projection, showing 

 minimum distortion. 



Africa, Globular Pro- 

 jection, from Map of the 

 Eastern Hemisphere. 



few exercises in the secondary schools which are pursued with 

 so much zeal and enthusiasm by the scholars, as those where 

 the character of the work is tested by its accuracy. This 

 being the case, some simple exercises in map drawing and in 

 making measurements on maps should prove most useful. 



A method of plotting the meridians and parallels of a hemi- 

 sphere, known generally as the globular, sometimes as the 

 arbitrary circle projection, is almost invariably to be found in 

 American geographies and atlases, and it is strange that a 

 method having no really good features to recommend it should 

 have received such general recognition. It is not a true pro- 

 jection in a mathematical sense, and differs from the stereo- 

 graphic in that the equator and central meridian are arbi- 

 trarily divided into equal spaces, the meridians and parallels 

 being represented by circular arcs passing through the points 

 thus found.* This method of map making has been criticised 



* There is a true projection, also called the globular, where the point of 

 vision is Y% times the radius beyond the sphere. This projection is difficult 

 to make, the circles of the sphere being projected generally as ellipses, and 

 the final result does not look very different from the arbitrary circle, globu- 

 lar projection, with which it is frequently confounded. 



