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tion to be made with lire plugs. Drain them after use, and dismantle, 

 dry, oil, and reassemble the chamber change-over valves. 



In using fire hoses at freezing temperatures, satisfactory results can 

 be obtained if good pressure is maintained ; however, when the pressure 

 is reduced or the hose is secured, the nozzle and plug become frozen, 

 and the nozzle must be replaced. 



Steam deck machinery should be carefully looked after to prevent 

 clogging with ice. In extremely cold weather it should be operated 

 daily, and condensed water drained out after use. If circumstances 

 require that steam capstans and winches be ready for instant action 

 in freezing weather, warm them up and leave them turning over at slow 

 speed, taking care that they are not permitted to stop. 



When operating in pack ice, keep the ship's main engines manned 

 and ready for immediate use at all times. In steam vessels, take pre- 

 cautions to insure that no water of condensation remains in the main 

 steam pipes or engine cylinders. 



Ice anchors should be stowed under shelter to prevent icing-up. 



ANCHORING 



It may be advantageous to lie at anchor when in brash, but as little 

 of the cable as possible should be paid out. The capstan should be kept 

 ready for weighing in case of the approach of large masses of pack 

 ice. When anchoring in rotten ice in shoal water, get into the ice as 

 far as possible to avoid the swell ; but if the water is deep and ice is 

 present, anchoring should be avoided. It may be preferable to lie 

 to and keep power available to move the ship as necessitated by the 

 shifting floes. It is not recommended to anchor to the bottom while 

 in pack ice, as in most cases it is useless and will probably result in the 

 loss of the anchor and cable. 



Having decided to ride to an ice anchor, choose a strong floe which 

 can shelter the vessel from the surrounding ice. To insure as nearly as 

 possible obtaining the shelter of a natural dock, it would be well in 

 making fast to a floe to take a position where a bight is formed by 

 two strong projections. Such places may often be found. They offer 

 at least moderate security in the event of other ice setting toward the 

 ship, the projecting angles of the floes receiving the first shock. If the 

 ice is not too thick, a dock can be sawed out. With two or more ships 

 in company, time is saved by employing all hands to cut one dock 

 large enough to take in all the ships. However, the degree of safety 

 will then be lessened, for the larger the dock the less likely it is to have 

 strength to resist pressure without eventually breaking. 



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