34 HYDROGRAPHIC MANUAL PaGE 250 



mate time in order to obtain a fixed position at the time of sight, when the Hnes of 

 position intersect at angles greater than 45°. Otherwise they should be used as indi- 

 vidual lines of position. 



34. HYDROGRAPHIC OPERATIONS 



341. Personnel and Their Duties 



The personnel required for various survey units has been briefly outlined in 142. 

 The specific duties of the various personnel are described here, except for those personnel 

 required only for the R.A.R. method of control, whose duties are described in 671. 



It is to be understood that the duties described under two different headings here 

 may be performed by one person or by two persons, depending on conditions. 



3411. Supervision by the Chief of Party 



During the progress of the survey the Chief of Party is required to supervise 

 closely the field work and to inspect frequently the boat sheets and Sounding Records. 

 He shall assure himself, by personal inspection of the field operations when necessary, 

 that all units in his party are carrying on such operations in accordance with the 

 requirements contained in the various manuals and in the project instructions. 



The Chief of Party should examine each boat sheet daily, if practicable, paying 

 particular attention to the adequacy and completeness of the survey with special 

 reference to the determination of least depths on shoals, the location of and data 

 relative to rocks and dangers of all kinds, the least depths on and the extent of bars 

 obstructing a fairway, and the development of all navigable channels. Each channel 

 should be studied carefully from the soundings plotted on the boat sheet to ensure 

 that the intensity of the soundings is sufficient to show the limits and navigable depth 

 of the channel throughout its extent or to determine where additional hydrography 

 is required. 



From this daily examination of the boat sheet the Chief of Party should indicate 

 to the hydrographer where additional lines, more intense development, or any other 

 data are required. Sounding Records and other recorded data should be examined 

 occasionally to make sure that they are being kept in accordancewith the requirements 

 of the Hydrographic Manual and are complete and satisfactory in all respects. Only a 

 general examination of the Sounding Records is required, the hydrographer in immediate 

 charge being specifically responsible for the day-to-day examination and for the approval 

 of each day's recorded data (see' 3246) . 



When it is impracticable for the Chief of Party to examine the boat sheets daily 

 because of the detached work of a \mit, he should make his examination at as frequent 

 intervals as practicable. 



Any general instructions issued to the hydrographer by the Chief of Party 

 should be written in the Sounding Record and signed by the Chief of Party. 



The supervision by the Chief of Party during the season and a final inspection of 

 the boat sheet when it has been completed must be in sufficient detail to ensure the 

 final adequacy and completeness of the survey before the departure of the party from 

 the working ground at the end of the season. 



The Chief of Party need not sign the Sounding Records, but in his approval of the 

 survey (see 7941 and 8437) he shall include a statement as to the amount of personal 

 supervision of the field work and as to the frequency with which he examined the boat 



