528 Correspondence on Magnetism of Ships, [Nov. 30, 



the spare compass-cards may never be kept with poles of the same name 

 nearest to each other, cases are supplied which will prevent the possibility 

 of their being packed improperly. 



" All ships are to be swung before sailing from the port where they fit 

 out, and subsequently once in each year, for the purpose of ascertaining 

 the errors of the compasses, also immediately on their arrival on a Foreign 

 Station ; or if there has been any great change in the ship's geographical 

 position since the errors were observed." 



APPENDIX II. 

 Suggested Rules relating to the Compasses of Iron Merchant Ships. 



" 1. It is deemed a necessary equipment for every iron ship to be fitted 

 with a Standard or navigating compass, in addition to one or more com- 

 passes for the use of the helmsman. 



" 2. That so far as the requirements of the ship will permit, special 

 arrangements be made in the course of construction for preparing a place 

 for this compass. 



" 3. That the Steering- Compasses being subordinate in importance to 

 the Standard Compass, less strict precautions are required for their position ; 

 but it would in all cases be desirable that these compasses (and of necessity 

 the steering-wheel) should not be placed within half the breadth of the 

 ship from the stern-post, rudder-head, and screw-well. 



" 4. The Standard Compass to be placed at such a height from the deck 

 (not less in any case than five feet) as to command a clear view of 

 the horizon above the bulwarks, and to be out of the way of the sails, 

 booms, &c. 



" 5. In ships built with their heads near the north, the Standard Com- 

 pass to be placed as far forward as the requirements of the ship will 

 permit. In ships built with their heads near the south, this compass to 

 be placed as near the stern as convenient, subject to the condition that it 

 should not be within half the breadth of the ship from the rudder-head, 

 stern-post, or screw- well. 



" In ships built near east and west, this compass should not be placed 

 near either extreme of the ship. 



" 6. The Standard Compass to be as far as possible, and not less than 

 ten feet, from the end of any elongated mass of iron, especially if vertical, 

 such as iron stanchions, capstan-spindles, steam- and stove-funnels, venti- 

 lating-shafts, <fcc. ; and no iron, subject to occasional removal, should be 

 placed within fifteen feet of the Standard Compass, either on the same 

 deck or below it. 



" 7. The Standard Compass to be placed as far as possible from trans- 

 verse iron bulkheads. 



" 8. It would be an extremely desirable arrangement for the deck imme- 



