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In such a case it may be desirable to work on the opposite side of the 

 ice masses, where possibly sufficient ice can be cut away to ease the 

 pressure and permit the vessel to pass. Blastin«r by jiunpowder or 

 dynamite has been used to free ships that have been caii<rht in the ice, 

 or to open a passage when an intervening floe has blocked the way to 

 open water. Passages opened by cutting or by blasting can sometimes 

 be kept open long enough for the ship to pass through by placing some 

 of the loose blocks of ice as wedges between the two floes, ahead and 

 astern of the vessel. Men working on the ice at such times, or those 

 crossing it on foot to look for a lead, should hold a boat hook or small 

 ice pole in their hands horizontally, to guard against falling through 

 a partly hidden crack. A strong plank drawn after one of the party 

 can be very useful for crossing places too wide to leap across. One 

 case of emergency rations for every man on board should be stowed 

 under cover topside when operating in the pack in order that packed 

 food can be readily tossed over the side if the vessel is nipped. Search 

 and rescue equipment should likewise be assembled, packaged, and 

 kept in readiness at all times. 



No material injury is likely to occur to the crew of a beset vessel if 

 they are on the alert and prepared beforehand, i. e., the boats furnished 

 with provisions, clothing, and portable fuel. This simple precaution 

 gives but little trouble and is well worth while. Boilers should be 

 banked or fires allowed to die out and the boilers drained. In the event 

 of being forced to winter in the pack, vessels fitted with propeller 

 wells may find it advisable to unship the propeller and rudder. Slack- 

 ing off the standing rigging is another precaution that should be 

 observed, as ice pressure tends to squeeze in the sides and lift the 

 masts. - Serious damage to a vessel is not necessarily of sudden occur- 

 rence ; it may be brought about by a gradual increasing of pressure on 

 both sides, until the vessel's bottom is nipped off, leaving her sides, 

 bow, and stern resting on the two floes, like a box without a bottom. 

 When the pressure eases, and the floes part, the vessel founders between 

 the two. 



Unintentional wintering in the polar regions no longer presents the 

 hazards that were faced by early explorers. Modern means of detec- 

 tion and communication assure that even a vessel with disabled radio 

 will be located expeditiously and her personnel evacuated. Those who 

 must stay with the ship for her security can be relieved and supplied 

 at regular intervals. In the Arctic, at least, winter weather condi- 

 tions in the pack ice are less severe than on land far to the south. 

 Sverdrup reports a minimum temperature of -46° F. for the two 



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