302 STAFF COMMANDER EVANS AND MR. A. SMITH ON THE MAGNETIC 
Table IV. — Iron-built Ships, Mercantile Marine. 
Ship. 
Compass. 
Place. 
Date 
Approximate coefficients. 
Exact coefficients. 
A 
B 
C 
D 
E 
% 
35 
e 
m 
@ ' 
° 1 
o / 
° I 
° / 
° t 
Rainbow 1 
Station No. 1 
Deptford 
July and Aug. 1 838 
+0 40 
— 50 36 
-11 4 
+ 1 23 
+0 38 
+ 012 
-•802 
-•173 
+•024 
+•01 
„ No. 2 
+0 3o 
-18 45 
-12 57 
+2 30 
+0 2 
+•010 
-•327 
-•217 
+•044 
+•00 
„ No. 3 
+0 42 
-15 46 
-10 39 
+3 7 
-0 2 
+ 012 
-•279 
-•181 
+•054 
-•00, 
„ No. 4 
+0 5 
- 8 5 
- 9 33 
+3 26 
+0 2 
+•001 
— •145 
-•161 
+•060 
■ 
+ •00 
1 
Ironsides 2 . . . 
Binnacle, or 
Liverpool ... 
Oct 27, 1838 . . 
0 0 
-24 16 
+20 50 
+2 15 
— 0 1 
•000 
-•416 
+•346 
+•039 
■00 
i 
steering. 
l 
Great Eastern 3 
Standard 
River Thames... Sept. 7, 1859 ... 
-0 10 
+23 13 
+25 38 
+4 21 
-0 37 
-•003 
+ •402 
+•408 
+■076 
-•01 
position. 
Portland 
....Sept. 12, 1859... 
-1 3 
+22 42 
+ 16 43 
+4 44 
-0 45 
-•018 
+•400 
+•27 2 
+•082 
-•01 
Compass aft 
River Thames... Sept. 7, 8, 1859 
-l 40 
+13 34 
+22 41 
+7 55 
-0 12 
-•029 
+•247 
+•359 
+•138 
-•00 
on platform. 
Compass on 
River Thames... Sept. 8, 1859 ... 
+0 3 
+31 56 
+ 17 47 
+4 31 
-0 9 
+•001 
+•551 
+•282 
+•079 
-•00 
fore bridge. 
• 
Clyde 
Standard 
(rrcenhithe ...T?eh. 21. 1863 
+0 41 
- 7 56 
+ 7 25 
+4 43 
+0 8 
+•012 
-143 
+•124 
+ •082 
• 
+•00 
position. 
City op Sydney. . . 
Standard 
Greenhithe ... 
.June 13, 1863 
+ 1 27 
- 3 29 
-18 51 
+4 32 
+0 23 
+•025 
-063 
-•311 
+•079 
+•00 
position. 
^(00“ 
feriton 
IPL-r 
fT' 
« | 19 
C j 21 
I* I 21 
ill I 14 
I ill | 45 
34 
■® ! 55] 
a 1 2 ? 
« 258 
ft. in. ft. in. 
1 Station No. 1, (near the binnacle) 13 2 distant from the extreme part of stern, 4 0,)- from deck. 
,, 2, 31 9 
,, 3, 48 3 
4 f 151 6 \ „ 
” ’ { 47 0 from knight head of stem J „ „ 
2 See Philosophical Transactions, 1839, Part I. p. 206. 
3 See Philosophical Transactions, 1860, Part II. p. 375. 
See Philosophical Transactions, 
1839, Part I. p. 167. 
ctetoXortl 
Table of Terrestrial Magnetic Elements. [1864.] 
Place. 
In British absolute units. 
Dip 6. 
Tan i. 
Horizontal force at Greenwich 
being unit*. 
Horizontal force. 
Vertical force. 
Horizontal force. 
Vertical force. 
Greenwich 
3-83 
+ 9-53 
+ 68 7 
+ 2*49 
1-00 
+ 2-49 
Greenhithe 
3-84 
+ 9*50 
+ 68 5 
+ 2*48 
1-00 
+ 2-48 
Sheerness 
3*83 
+ 9*50 
+ 68 2 
+ 2-48 
1-00 
+ 2-48 
Portsmouth 
3-86 
+ 9*48 
+ 67 50 
+ 2*45 
1-01 
+ 2-47 
Portland 
3-88 
+ 9-50 
+ 67 45 
+ 2-44 
1-01 
+ 2-47 
Plymouth 
3-86 
+ 9-54 
+ 67 58 
+ 2-47 
1*01 
+ 2*49 
Milford 
3-62 
+ 9-80 
+ 69 44 
+ 2-71 
•95 
+ 2-56 
Greenock 
3-38 
+ 10-04 
+ 71 23 
+ 2-97 
•88 
+ 2-63 
For British absolute units multiply by 3-83. 
For Foreign absolute units multiply by 1-76. 
11 
