Page 691 the smooth sheet 745 



745. Verification of the Control 



The plotting of the control must be verified by a person other than the one who did 

 the plotting. The verification must consist of the actual replotting of the stations, 

 their placement in the correct quadrilaterals of the projection, and their identification 

 bv the correct names. 



Only after this has been done, are the symbols and names to be inked. 



746. Projection and Control Data 



The projection and control data shall be given in the lower right-hand corner of 

 the smooth sheet, and rubber Stamp No. 42, Hydrographic Survey, shall be used for this 

 purpose. The center of the stamp should be about 7 inches from the right edge. 



Entries should be made in all of the applicable spaces of the stamp. The initials of 

 the persons plotting and verifying each of the items listed should be entered, together 

 with the dates. It is important that the verification information be given, otherwise 

 unnecessary duplication results, since 

 the Office cannot assume a field verifi- 

 cation unless evidence of this appears 

 on the survey sheet. If an item in the 

 stamp is not applicable to a particular 

 survey, as where no hydrographic sta- 

 tions are on the sheet, an explanatory 

 entry should be made, such as "none" 

 opposite "Hydro. Sta." 



The registry number of the survey 

 shall be given if known, as well as the 

 field number (see 154). Opposite the 

 item "Ref. Sta." on the stamp, the 

 name and date of establislunent of some 

 one triangulation station on the sheet, 

 should be given. The latitude and longitude with seconds in meters shall be given 

 immediately below. Wliether the position has been adjusted or not shall be indicated 

 by ruling out the inapplicable abbreviation following the data, if this is known. 



All of the projection and control data shall be shown in black ink. A facsimile of 

 Stamp No. 42 with the necessary data entered is shown in figure 154. 



75. TRANSFER OF THE TOPOGRAPHY 



The hydrographic smooth sheet, as finally registered, is not the authority for the 

 topography, which is surveyed on a separate sheet. Wliere the topography is surveyed 

 by planetable, it is usually done in the same season, immediately preceding the hydro- 

 graphic survey and under the direction of the same Chief of Party. In the case of air 

 photographic surveys, however, the photographs may have been taken several years 

 earlier and the planimetric maps may have been completed some time before the hydro- 

 graphic survey. Infrequently there is no contemporary topographic survey; that is, no 

 survey accomplished during the same season or in a season immediately preceding the 

 hydrographic survey, which is considered to be a part of the same project. 



The Chief of Party shall have the hydrographic party verify, and revise if neces- 

 sary, the high-water line and all topographic details offshore therefrom, which are 



No. 42 HYDROGRAPHIC SURVEY 



Field No. P.f .7 P.^J, I . . Reg. No. . U 7 .^A7J. . . 

 Scale 1:..§P.'.P.9P.... Plotted.: Verified 



Projection :.. ^.-.'^ .?..:. .^. P. .'^. . . . 



Tri. Sta :..^-.^-.C..:..f-..q.^..., 



Topo. Sta :..M-^..?;.:..'f-..^-.'K-... 



Hydro. Sta : . . M- ^l- .^^ . : . .f -. P..¥.: . . 



Datum .^Ofi T.^. ..6MP.'?. '. 9 A /v. . ( ?.^. r. . . . , 



Ref. Sta. . . ?A k P. . . ^( #. '^.Q.'. .JP.^^. 



Lat i.\.\. ,i^: ff,^. P. . m. ( Adj. 



Long.. . .^.?.» . . A!.'. ...A 7A. 7. . m. ( Unadj. 



Figure 154.— Projectiou and control data for smooth sheet. 



