Page 331 equipment and instruments 4311 



used in the field and the return of these instruments to the place provided for their 

 stowage. He should make periodic examinations of all instruments on board, pro- 

 vide for their maintenance, make necessary repairs, and keep an accurate inventory. 

 At the end of each season, worn out, damaged, and surplus instruments should be re- 

 turned to the Washington Office. An officer in charge of any phase of detached oper- 

 ations shall be responsible for the care of his instruments. Before having them stowed 

 away he must be sure that they are cleaned, dried, oiled, and packed in their original 

 boxes. 



4311. Periodic Tests 



Periodic tests shall be made of various equipment and instruments to check their 

 accuracy, determine their errors, and make corrections if possible. Some are tested 

 during lay-up and overhaul periods while others should be tested at the beginning of 

 and during field operations. The latter is particularly applicable to the magnetic 

 compass as explained m 4415. Tests required in connection with other equipment are 

 included with the descriptions of the equipment. 



4312. Care of Equipment 



The safety of the vessel and its occupants often depends directly on the accuracy 

 and reliability of the navigation equipment and the speed and ease with which it can 

 be used. 



The equipment located inside the pilothouse and other parts of the vessel shall be 

 kept free from dust, dirt, tarnish, rust, and salt deposits at all times. It should be 

 lubricated according to the instructions for the equipment and inspected and over- 

 hauled periodically by experts if the instructions so specify. Equipment kept in boxes 

 or cases when not in use, such as the azimuth circle, shall be thoroughly cleaned and 

 dried before being stowed away, all moisture and salt deposits being first removed. 



Equipment installed where it is exposed to the elements shall be kept clean and in 

 perfect condition at all times. Instruments that are not protected by fitted metal 

 covers shall be provided with canvas covers. Exposed equipment shall be kept 

 covered when not in use, except when underway when it may be needed at any moment. 

 All equipment shall be handled carefully to avoid excessive wear and possible damage. 

 Navigation equipment that requires illumination at night shall be inspected at sunset 

 to ensure that all lights are in proper working order; any deficiency shall be corrected 

 at once. Such inspection may be omitted during extended periods in repair yards 

 and alongside docks. 



All survey equipment should be cleaned periodically. Surfaces that are apt to 

 become frozen or stuck when stowed for any period of time, should be moistened slightlj^ 

 with oil or tallow after cleaning and before reassembling. 



Sounding wire, even when galvanized, is subject to rust. The wire on the sounding- 

 machine reel, when not in use, should be dried, oiled, and well wrapped with oil-soaked 

 cloths, to provide protection from the weather. When soundmg, a brush dipped in 

 cup grease should occasionally be held against the wire on the reel as it is being 

 reeled in. (See 4658.) 



When not in use, the sounding machine should be protected from the weather by 

 a canvas cover. The outrigger and sheaves should always be well oiled and should 

 frequently be tested to ensure that the sheaves are turning freely. 



