14 NAUTICAL CHART MANUAL 



ORIGINAL SOURCES 



The original source material is to be used in the compilation of New Charts and in cor- 

 recting existing charts. Large-scale charts that have been corrected from original source 

 material become sovu-ce material for small-scale charts. In such case, the original source 

 material is referred to only where necessary to check information questioned. 



All available sources of information should be used in the construction of a chart, including 

 the following: 



1. Original C. & G.S. topographic and hydrographic survey. 



2. Descriptive reports accompanying such survey. 



3. All chart letters regarding area of chart. 



4. Corps of Engineers Surveys. 



5. Corps of Engineers Annual Reports. 



6. U.S. Geological Siu-vey quadrangles. 



7. General maps from map files. 



8. Chart of the area made by other nations. 



9. Coast Pilots. 



10. Light and buoy list (U.S. Coast Guard). 



11. Notice to Mariners when conflicts arise between surveys and existing charts. 



12. Air photos which supersede surveys. 



13. Triangulation records. 



14. Descriptions of triangulation stations. 



15. Port Series publications. 



16. Aid Proofs. 



17. Standards. 



18. Corps of Engineers Project Maps (in book form). 



19. Corps of Engineers District Intracoastal Waterway Maps. 



20. Corps of Engineers Mississippi River Commission Maps. 



21. List of Bridges over navigable waters. 



Cartographers should not hesitate to initiate a letter of inquiry whenever information is 

 lacking, or when existing information requires checking. 



