288 STAFF COMMANDER EVANS AND MR. A. SMITH ON THE MAGNETIC 
diminished. This is doubtless the effect of the iron plating, which acts as a — Jc. No 
doubt in iron-plated iron-built ships the effect is the same, and the heeling error is 
probably diminished and not increased by the effect of the iron plating. Observations of 
vertical force have not been made in the main-deck compasses of these ships ; but pro- 
bably there the heeling error would be small, and possibly be a heeling error to leeward. 
We must observe that there has not been an opportunity of making an exact com- 
parison of the values of the heeling coefficient deduced from theory with those deduced 
from actually heeling and swinging the ship. The great amount of labour and time 
required to heel a ship of the class we are discussing, and swing her, has prevented such 
observations being made in more than a very small number of cases. In the case of 
the Warrior, Black Prince, and Defence, advantage was taken of their being heeled at 
Class 
of 
Ship. 
Iron 
plated. 
'July 1862. 
Jan. 1863 . 
Sept. 1862. 
Jan. 1863 . 
April 1864. 
Oct. 1864. 
Dec. 1864. 
Oct. 1864. 
ships, , Dec. 1864. 
iron- " 
' Feb. 1862. 
Jan. 1863 . 
April 1864. 
Aug. 1862. 
Dec. 1863. 
Feb. 1864. 
(Jan. 1865 
April 1863. 
June 1863. 
Feb. 1864. 
Wood 
ships, 
ptted. | 1864 ‘ 
| June 1864. 
1 
Iron 
ships. 
( July 1863. 
Nov. 1863. 
Sept. 1863. 
Feb. 1863. 
Feb. 1863. 
Mar. 1863. 
June 1863. 
Name of Ship. 
Warrior 
,, Lisbon 
Black Prince 
„ Lisbon 
Achilles (Standard aft) 
„ (Standard forward), 
Defence 
„ Lisbon 
Resistance 
Hector 
Valiant 
Royal Oak 
Prince Consort 
Ocean 
Enterprise (Iron topsides) . . 
Orontes 
Tamar 
„ (Binnacle over rudder) 
Wye 
Caradoc 
Clyde 
Industry 
City of Sydney 
Direction of Head in 
building. 
N. 3°E 
S. 20° E 
S. 51° 40' E. ... 
S. 47° W 
S.86i°W 
S. 20° E. 
S. 87° W 
Plated S. 49°E 
Plated S. 39° W 
Plated S. 79° E 
Built and plated 
S. 56° W. 
N. 66° W 
West 
Probably to E.S.E. .. 
Probably to N. by W. 
Probably to N.E. . . . 
Probably to S. by E. 
Probably to W.N.W. 
•945 
•971 
•870 
•896 
1-217 
1-240 
1040 
•968 
1071 
1044 
•848 
•929 
•622 
1117 
1-248 
M95 
1002 
1-275 
•859 
1-246 
+•069 
+•106 
+•118 
+•262 
+ 111 
+•194 
+■210 
-•172 
-•165 
+•138 
+•117 
+•157 
+•176 
+ 190 
+•120 
+•045 
+•127 
+•038 
+ 112 
+•152 
+ 147 
+•294 
+•252 
Heeling coefficient from 
Heeling 
coefficient 
windward. 
vertical 
induction 
in trans- 
verse iron. 
vertical 
force and in- 
duction in 
vertical iron. 
+0 43 
+0 32 
+1 06 
+0 50 
+1 49 
+1 22 
+1 01 
+° 43 
+0 48 
-0 11 
+0 09 
-0 05 
+0 50 
+0 52 
+0 43 
+0 50 
+0 43 
+0 49 
+0 37 
-0 23 
-0 18 
+0 40 
+0 41 
+0 27 
+0 25 
+ 1 29 
+ 1 18 
+0 51 
+0 33 
+0 42 
+0 08 
— 0 03 
-0 06 
+0 59 
+0 30 
+0 36 
+1 04 
+0 45 
+0 14 
+0 08 
+1 18 
+0 53 
+0 48 
-0 03 
+0 45 
+0 37 
+0 11 
+0 48 
+0 24 
+0 23 
-0 17 
-0 19 
+0 07 
+0 04 
+0 16 
-0 24 
-0 08 
+0 19 
-0 34 
-0 15 
+0 37 
-1 09 
-0 29 
+0 36 
+0 28 
+ 1 04 
+0 31 
+0 28 
+0 20 
+0 42 
+0 51 
+ 1 10 
+0 27 
+0 34 
+ 1 0 
+0 14 
+0 01 
+0 15 
+0 35 
+0 47 
+1 22 
+0 18 
-0 23 
-0 05 
+0 46 
+0 45 
+ 1 31 
