66 OUTLINES OF NATURAL PHILOSOPHY. 



the angle PAB, such as it would be measured at 

 A. In the same way the azimuth at B may be 

 found. 



d. When these calculations are applied in small tri- 

 angles, they naturally become much more simple. 

 The process now described) contains a general so- 

 lution of spheroidal triangles, which have one angle 

 at the pole, whatever be the oblateness of the sphe- 

 roid, and whatever be the magnitude of the tri- 

 angles. 



69. The Artificial Globe is a delineation of 

 the surface of the earth, and the circles belong- 

 ing to it, on the surface of a sphere, moveable 

 about an axis ; it serves to give a correct notion 

 of the figure and proportion of the parts into 

 which the earth's surface is either naturally or 

 artificially divided, as well as to resolve many of 

 the problems of geography, when great accura- 

 cy is not required. 



A contrivance of the same kind is applied to the hea- 

 vens. The uses of the celestial and terrestrial 

 globes are fully explained in most of the treatises 

 on Astronomy and Geography, 



JO. A Map is |a representation of the whole, 

 or of a part of the earth's surface on a plane ; 



and 



