Magnetic compass

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Image
The magnetic compass is fitted on the upper bridge exactly center line of the ship   It is referred to as standard compass     1. D ry C ard    2. W et C ard   A compass point north because all magnets have two poles north pole, south pole.   The north pole of the one magnet attracted towards the south pole of another magnet     DRY CARD COMPASS   A light aluminum ring about 254mm in diameter is attached to a brass hub by silk cord which is threaded in and out through holes in the ring.   This tight silk cord is act like bicycle wheels.   There is no other connection or support between the ring and the hub.   Silk cord is used because it doesn’t shrink or stretch due to moisture or change in atmospheric temperature.     Card support: -     The bottom of the hub has small cap fi tt ed with a sapphire bearing surface.   This rests on a pivot tipped with iridium which is hard nonmagnetic metal....
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HOW CARRIAGE OF TIMBRE ON DECK EFFECTS THE STABILITY OF SHIP

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A vessel with a considerable quantity of timbre as deck cargo is likely to be tender at the commencement of the voyage itself, owing to such weight loaded so high up on the ship while we are carrying timbre, there we can see a lot of possibilities of changing stability by changing the value of GM.


ABSORPTION OF WATER BY THE TIMBRE ON DECK DEPENDS ON


  1. Type of wood.
  2. Nature of timbre – logs , blocks, planks ,boards etc. the greater the surface area exposed , greater the absorption.
  3. Age of timbre – new timbre would contain water content in its wood hence not absorb much water whereas old timbre would be dry and can absorb a lot of water.
  4. The amount of precipitation and spray experienced.
The amount of water absorbed is variable and though it can be as high as 20% of weight of the timbre , it is generally around 10-15%.


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The magnetic compass is fitted on the upper bridge exactly center line of the ship   It is referred to as standard compass     1. D ry C ard    2. W et C ard   A compass point north because all magnets have two poles north pole, south pole.   The north pole of the one magnet attracted towards the south pole of another magnet     DRY CARD COMPASS   A light aluminum ring about 254mm in diameter is attached to a brass hub by silk cord which is threaded in and out through holes in the ring.   This tight silk cord is act like bicycle wheels.   There is no other connection or support between the ring and the hub.   Silk cord is used because it doesn’t shrink or stretch due to moisture or change in atmospheric temperature.     Card support: -     The bottom of the hub has small cap fi tt ed with a sapphire bearing surface.   This rests on a pivot tipped with iridium which is hard nonmagnetic metal....
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