308 



Variation and Dip of the Magnetic Needle. 



Table exhibiting the Dip of the Magnetic Needle in different parts of the United 



States. 



From the preceding observations it seems impossible satisfac- 

 torily to determine what changes the dip of the needle has ex- 

 perienced in this country. From the course of the observations 

 made in other places by Prof. Bache, it may be inferred that the 



