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In this manner, much time may be saved in taking on water, which 

 is usually done at about 4,000 gallons an hour. 



Although individuals vary regarding a taste for salt, water with a 

 salt content of 1 or 2%o will often be chosen in preference to distilled 

 water. A salt content as hig*!! as 10%o can be tolerated in emergencies 

 without harmful effects, and such water can be used freely in cooking. 

 The boiler-water kits carried by most modern ships can be used for 

 water analysis. If the sample under test lies off the scale of the 

 apparatus, dilute it one-half, four-fifths, or nine-tenths with dis- 

 tilled water, and multiply the salt content so found by 2, 5, or 10. 



Ships making their own distilled water from sea water occa- 

 sionally encounter concentrations of plankton that yield a volatile 

 oil, which gives a somewhat fishy odor and taste to the water. No 

 harmful effects have resulted from the ingestion of such water; but 

 when the water was used to wash photographic negatives, the film 

 became oil-spotted. This condition can be recognized by the deposi- 

 tion of green scale instead of the usual tan scale in the tubes of the 

 distilling plant. 



DAMAGE AND REPAIRS 



Typical forms of damage to vessels by ice are : 



(a) Breaking of propeller blades, rudder head, or rudder. 



{h) Damage to steering gear. 



{c) Damage to stem and perforation of plating, causing leaks in 

 the forepart of the vessel. 



[d) Buckling of plating and tearing out of rivets due to ice pres- 

 sure, leading in extreme cases to crushing of the hull and breaking of 

 frames. 



As a rule, when a vessel receives damage under its stern, repairs 

 should not be undertaken until the vessel is first trimmed well down 

 by the head. This is accomplished by pumping the water out of 

 the stern tanks and flooding the fore-peak and forward ballast tanks. 

 If these measures prove inadequate, a suitable amount of cargo will 

 have to be transferred forward from the after holds. 



In the event that the steering gear breaks down, it is possible to 

 steer with the aid of the two rudder pendants secured to the rudder and 

 run to a stern capstan or cargo winch. If the rudder has been carried 

 away a similar steering arrangement may be improvised with the 

 jury rudder. 



Repairs to damage in the forepart of a vessel are generally restricted 

 to preventing water from getting into the ship. It may be necessary 

 to transfer water or fuel aft, in order to raise the bow sufficiently out 



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