5. HYDROGRAPHY 



163 



hydrographic surveys, except wire-drag sur- 

 veys which are recorded in Form 411. The 

 soundings of each hydrographic survey unit 

 shall be recorded chronologically in a sep- 

 arate series of volumes for each hydro- 

 graphic sheet. Under no circumstances shall 

 hydrography which is to be plotted on two 

 or more separate hydrographic sheets be in- 

 tentionally recorded in the same volume. 

 Sounding volumes shall be numbered con- 

 secutively as the survey progresses. If more 

 than one hydrographic survey unit surveys 

 in an area covered by a single sheet, a tem- 

 porary series of numbers shall be used by 

 each unit which uses more than one volume. 

 When the survey is complete, the records 

 for each survey unit shall be grouped in 

 proper order, the various groups combined, 

 and the complete set of records shall be num- 

 bered consecutively and permanently (see 

 1-32). The field number and registry num- 

 ber shall be lettered in pencil on the Title 

 Page of each record book. 



The record must be unmistakably legible. 

 Fine lettering is not required, neither is it 

 necessary to print in making entries, but it 

 is essential that every numeral, abbreviation, 

 and word be clear beyond doubt. The work 

 must be recorded in a systematic manner 

 and, insofar as possible, in the form pre- 

 scribed in this Manual. 



The record book should be protected while 

 in use by a paper or other suitable cover. 

 This is especially important in launch hy- 

 drography where spray, rain, or other con- 

 ditions may result in damage to the records. 



A sounding record is essentially a time 

 record of a recurring series of acts and 

 events, with occasional interspersion of re- 

 lated material. The record must clearly 

 show the relationship between these acts and 

 their recorded times. Generally, each entry 

 should appear on the same horizontal line 

 with its respective time, but occasionally, 

 miscellaneous notes may be made at other 

 places and referred to their corresponding 

 times by distinctive reference marks. The 

 approved manner of recording hydrography 

 is shown in Figures 64 to 66. 



While space should not be wasted in the 



sounding record, no attempt should be made 

 to save it by crowding the data. It is fre- 

 quently necessary to scale soundings from 

 the fathogram at irregular intervals in order 

 to plot bottom profiles correctly. When sound- 

 ing in an area of uneven bottom, the sound- 

 ings at regular intervals should be recorded 

 on alternate lines of the record book, but 

 when the bottom has a generally smooth 

 and even slope a sounding may be recorded 

 on each line. 



Recorded data must never be erased, all 

 corrections being made by crossing out the 

 incorrect entry and making the correct one 

 above or to one side, where it cannot be 

 misinterpreted. This prohibition does not 

 apply with respect to soundings scaled from 

 a fathogram when congestion and ambiguity 

 would result from its application. Entries 

 which are rejected for any reason shall be 

 indicated by an R written boldly over the 

 entry. 



Rubber stamps are provided and must be 

 used for recording nearly all the information 

 required at the beginning and end of the 

 day's work and for many of the entries made 

 during the day. 



5-86 Use of abbreviations. — The prin- 

 cipal duties of the recorder are described in 

 5-54. Because of the amount of recording 

 and the speed which is often required, ab- 

 breviations for many of the terms and ex- 

 pressions which are used repeatedly are ad- 

 vantageous. The lists which appear here 

 are to be considered standard. This does not 

 preclude the use of common well-known ab- 

 breviations which may not be included. The 

 recorder should know these abbreviations 

 and use them where applicable. When it is 

 found necessary to use unlisted abbreviations 

 they should be listed and explained in the 

 first volume of the sounding records. 



Figure 59. — Record of sounding apparatus used. 



