538 MAGNETIC AL OBSERVATIONS. [aPP. N* IX. 



the variety of causes (arising out of the unccjual distribution 

 of iron in different ships, whereby numerous local attractions 

 arc formed) wliich contribute to the multiplication of those 

 errors : it is, therefore, with deference that I submit these 

 deductions, particularly as I conceive it will require observa^ 

 tions to be made under a vast variety of circumstances, and 

 in many different vessels, before correct and satisfactory con- 

 clusions can be drawn. It is onlij then as a step towards fa- 

 cilitating such general conclusions, the importance of which 

 to our maritime concerns is so obvious, that I am induced to 

 offer tlicse observations and remarks. 



TABLE 



