92 ON MAGNETISM. 



equal total magnetic force. The numbers upon the 

 latter system of lines shew the value of the total force 



Fig. 36. 



(A is the southern pole of greatest magnetic intensity, and B the primary pole of small 

 intensity.) 



in Metric measure. To present more vividly to the eye 

 the general facts of dip and total force over the earth, 

 Figure 37 is drawn, exhibiting the directions of dip and 

 the magnitude of total force along a meridian of the 

 earth. The magnitude of force is shewn rudely by the 

 lengths of the symbolical needles at the different points 

 of the meridian. The map is on the orthographic pro- 



