935 HYDROGRAPHIC MANUAL PaGE 860 



tions of the reviewer regarding the disposition of rocks and shoals from prior surveys 

 and of charted information originating witli other sources. 



935. Approval by Administrative Officers 



After the hydrographic survey has been verified, reviewed, and inspected, the com- 

 pleted sheet, the Descriptive Report, and the written review are examined thoroughly 

 and read carefully and approved by four administrative officers in the Washington 

 Office, who are charged with the prosecution of the field work and with the application 

 of the results to the charts. Before its final approval the written review may be 

 amended or supplemented. 



After approval a copy of the written review is forwarded to the Chief of Party under 

 whose direction the field work was accomplished, and he is requested to forward it 

 to the hydrographer who was in immediate charge of the work, if the latter is no longer 

 attached to his party. A copy of the written review of a survey on which ofiice work 

 was done at a Processing Office is also forw^arded to the officer-in-charge of that office. 

 This serves to call to the attention of those responsible any shortcomings in the field 

 or office work and sets standards for future work of like character. 



94. COMPUTATION OF BUOY POSITIONS 



Positions of buoys should be computed as soon as possible after the field observa- 

 tions have been completed. Buoys are left at their stations only as long as they are 

 needed for control of the hydrographic survey, so the computations should be made 

 and the positions adjusted without delay in order to discover any deficiency in the 

 observations which should be remedied before the buoys are removed. Wlien many 

 buoy stations are being located, as at the beginning of a field season or in extensive 

 traverses, one or two persons should be assigned to this duty of computing and check- 

 ing the computations. This assures the availability of the positions for use on the 

 boat sheet in a short time without overtime work by personnel with other regular 

 duties. 



The observations should be recorded and the computations made on regular forms, 

 preserved in three-ring binders made to take letter-size paper (8 by lOK inches). 

 Where there are many buoy stations it will be convenient to use three or four binders 

 to segregate the records, as follows: (a) Buoy Data Book, (6) azimuths, (c) traverse 

 computations, and (d) computations of tie-in buoys. 



Of the four, the "Buoy Data Book" is the most important. It should be on the 

 ship's bridge at all tunes during a buoy-control survey. In it should be kept all records 

 of buoys anchored at, and removed from, stations, and all records of distance measure- 

 ments. It should contain the complete record to date, and blank forms for future use, 

 as follows: 



Form 714, Abstract of Buoys Planted. 

 Form 777, Taut-wire Traverse Observations. 

 Form 713, Buoy to Buoy Distances by Bomb. 

 Form 715, Abstract of Bombed Distances. 



The second binder should contain the azimuth data, including Form 718, Abstract 

 of Buoy to Buoy Azimuths, and Form 720, Azimuth by Inclined Angles. 



Wliere a buoy traverse is computed by using geographic positions, these computa- 

 tions are made on Form 27, Position Computation, Third-Order Triangulation, and 

 these should be kept in a third binder. 



