Page 693 the smooth sheet 752 



(c) From an offshore survey (one where another survey exists or is contemplated between it and 

 the shore). If the survey is on the same scale as the topographic survey, the high-water line only 

 should be transferred but not the topographic detail adjacent to the shore. 



(d) From wire-drag smooth sheets where the drag limits are not very close to the shoreline. 

 Where the shoreline is shown, it is not necessary to transfer all the rocky detail adjacent thereto. It 

 is usually sufficient to show only such off-lying rocks and reefs as were factors in delimiting the inshore 

 extent of the dragged area. 



752, The Shoreline 



The shoreline which is shown on the topographic survey and hkewise on the smooth 

 sheet, and on the charts pubHshed by the Coast and Geodetic Survey, is a mean high- 

 water line, except m marsh and mangrove areas. In the latter cases the shoreline is the 

 visible edge of the marsh or mangrove, because this is the line which appears to the 

 mariner as the shoreline. 



After transfer of the topography, the mean high-water line should be inked at once, 

 except in those areas where the boat sheet dislcoses a possible conflict between the shore- 

 line as located by the topographic survey, and the hydrography. In such cases the 

 shoreline shall be left in pencil until the soundmgs have been plotted and a study made 

 of the results. All details offshore from the high-water line must also be left m pencH 

 pending the plotting of the hydrography. 



The mean high-water line on fast solid land shall be shown on the smooth sheet 

 by a firm continuous solid black line about 0.4 mm thick. The shoreline of marsh, 

 swamp, and mangrove areas shall be shown by a fine solid black line about 0.2 mm 

 thick. (See 962.) The outlines of small details of waterfront areas, such as small piers 

 and bulkheads, shall be shown by moderately fine lines, somewhat finer than those used 

 for the mean high-water line on fast land, in order that the small details of pier lines and 

 pier corners may not be obliterated. (See fig. 169.) 



753. Revisions by Hydrographic Party 



The hydrographic party is responsible for the correctness of the topographic detail 

 falling within the limits of the hydrographic survey, including the high-water line and 

 waterfront details if the survey is carried close thereto. Where the topographic survey 

 was not made m the same season as the hydrogi'aphic survey and under the direction 

 of the same Chief of Party (see 381), revisions or corrections thereto shall be shown on 

 the smooth sheet, according to the following instructions: 



(a) Where the revised shoreline or topography has been determined by standard topographic 

 methods or methods resulting in an equal accuracy, it shall be inked in a solid red line. 



(b) Where the revised data are only sketched by careful estimation or are based on sextant 

 fixes, or sextant cuts, they shall be inked in broken red lines. Where the shoreline has been sketched 

 by the method described in 3812, it shall be left in a broken pencil line by the field party, to be inked 

 in the Washington Office in a broken black line when, at the time of review, no accurate survey is 

 known to be contemplated. 



(c) The thickness of the inked lines shall be equal to those prescribed in 752 (i. e., 0.4 mm for the 

 shoreline of solid ground and 0.2 mm for the visible edge of marsh or mangrove areas). 



(d) Appropriate notes shall be made both on the smooth sheet and in the Descriptive Report 

 explaining the discrepancies and the methods used in determining the positions of the revised data. 



The red color will distinguish immediately between shoreline ajid topography 

 which have originated with other sheets, and the revised data for wliich the smooth 

 sheet and the hydrograpliic party are the authority (see fig. 169). 



