286 Admiral Krusenstern on the Local Attraction of Vessels. 



Experiments made to ascertain the quantity of local attraction 

 in H. I. M. S. Olynip, made on the 2d of July 1824, in the 

 Roads ofCronstadt, by Admirals Count Heyden and Kru- 

 senstern. 



Bearing 



of Ship': 



Head. 



N 10° 

 20 

 30 

 49 

 53 

 63 

 73 



S 86 E 

 70 



55 

 45 

 35 

 27 

 15 

 5 



Bearing of 

 Shore Sta- 

 tion from 

 Brig. 



N26°40'E 

 26 40 

 26 20 

 25 40 

 25 40 

 25 20 



25 40 



26 00 



26 20 



27 20 



27 40 



28 20 



28 50 



29 20 



30 00 



Bearing of 



Brig 



from Shore 



Station 



S 28° 15' W 



28 30 



29 15 

 29 15 

 29 45 



29 15 

 31 15 



31 15 



31 15 



31 45 



31 45 



31 15 



31 15 



31 15 



30 15 



Local 

 Attrac- 

 tion. 



Bearing 



of Ship's 



Head. 



1°35' 



-0 15 



S 9°W 

 25 

 33 

 66 

 86 



N 78 W 

 70 

 60 

 51 

 45 

 36 

 25 

 20 



9 



3 



Bearing ol 

 Shore Sta- 

 tion from 

 Brig. 



Bearir. » of 



Brig 



from Shore 



Station. 



N30°20'E 

 30 20 



30 40 



31 oo 

 31 oo 



30 45 



31 20 

 30 40 



30 40 



31 00 

 30 20 

 29 40 

 28 40 

 26 40 

 26 40 



S 29° 45' W 

 29 30 

 29 45 

 29 00 

 29 00 



28 45 

 28 45 

 28 30 

 28 45 

 28 45 

 28 15 

 28 15 

 28 15 

 27 30 

 27 45 



Local 

 Attrac- 

 tion. 



+0°35' 

 +0 50 

 + 55 

 -j-2 00 

 +2 00 



+2 00 

 +2 35 

 +2 10 

 + 1 55 

 +2 15 

 +2 05 

 + 1 25 

 +0 25 

 -0 50 

 -0 55 



Note. — It gives us much pleasure to see this highly important 

 nautical improvement making such rapid strides towards being 

 generally adopted. Our own ships of war are in future all to 

 be supplied with a correcting plate, and we understand that 

 both the Dutch and American marine have ordered plates 

 for the purpose of experiment and correction. Our merchant 

 service will, we have no doubt, soon follow these examples. 

 In the mean time, in order to accelerate as much as in our 

 power this desirable practice, we publish, with Mr. Barlow's 

 permission, the following letter which he has received from 

 one of our most distinguished naval Boards, whose opinion 

 will, we have no doubt, have a powerful influence in recom- 

 mending the adoption of the principle 'by the more respect- 

 able class of our merchant vessels, as that of the Longitude 

 Board has been the means of introducing the practice into the 

 navy. — Edit. 



Copy of a Letter from J. Herbert^ Esq. to Mr. Bar-low. 



Sir, Trinity House, London, 17th June 1824. 



The General Court of this Corporation having had under 

 consideration the importance and utility of your discovery of 

 a method for correcting the local attraction and consequent 

 deviation of the compass on ship board, and being of opinion 

 that the practice of the science of navigation will be greatly 



benefited, 



