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ice, but in the vessel's bow sliding up on the ice edge, so that she 

 becomes fast. This tendency to slide up on the ice depends on the lines 

 of the forward part of the ship and on her loading and trim. One 

 or more of the following methods may be used for releasing the 

 vessel. 



1. Go full speed astern. This may extricate the vessel, but it is 

 not always successful. If it fails, stop the engines, put the helm 

 over and go full speed ahead. By putting the helm over alternately 

 from side to side and going full speed ahead, it is often possible to 

 induce the stern to move a little to one side, so that the bow will move 

 slightly ; then by going full speed astern the vessel may slip off the ice. 



2. Try to split the ice by striking it at the point of pressure with 

 crowbars. This is one of the simplest methods. 



3. List the vessel by transferring water in the ballast tanks. 



4. Alternately flood and empty the fore and after peaks. First 

 flood the fore peak, and then empty the fore peak and flood the after 

 peak. 



5. If the foregoing methods fail, try an ice anchor or warp attached 

 to the ice astern. Pass the anchor cable through the mooring chock 

 on the forecastle and lead it to the windlass. Take a strain while the 

 engines are going full astern. An alternative of this method is to 

 take an ice anchor abreast of a mast with the heaving line to the 

 masthead. 



6. Lay out ice anchors on each beam and heave first on one and 

 then on the other, keeping the engines going full astern. 



7. If all these means fail, try blasting. The usual position for 

 placing explosive charges is about 35 or 40 feet from the ship, abeam 

 of the bridge. If the ship is held only forward, good places are 

 directly ahead and at each side of the bow, the idea being to break 

 off a portion of the floe without enough buoyancy to support the ship. 

 A blasting charge of 8 ounces of guncotton in a hole 6 inches deep 

 will blow a hole either through the ice or deep enough to use an 181/2- 

 pound charge effectively, and this is the amount generally necessary. 

 At the time of the detonation, the engines should be working full 

 astern. It may also be helpful to hold a strain on ice anchors laid 

 out astern. 



8. Wlien all else fails, a ship can be sawed out of the ice, provided 

 the ambient air temperature is not below the freezing point of the 

 sea water. The classical example of this feat was set by the Belgica 

 of the de Gerlache Antarctic expedition. Dr. Frederick A. Cook who 

 was later well known in connection with the North Pole, was ship's 



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