8582 HYDROGRAPHIC MANUAL Page 806 



Changes in methods and equipment that will have no effect on the accuracy of 

 operations, such as the design of a new type of signal or buoy, may be used without prior 

 approval of the Washington Office. Those changes which do affect the quality of the 

 work, such as new instruments, etc., may not be used in actual survey work until 



approved by the Office. 



8582. Submarine Features of Interest 



Modern methods of surveying are disclosing in considerable detail submarine 

 features of interest to scientists and geomorphologists, as well as to navigators. Most 

 prominent among these are the large submarine valleys and canyons indenting the 

 continental shelves and slopes, and the large submarine mountains. There are many 

 other submarine features of less spectacular size, such as silted areas and sand waves, 

 which the survey may disclose that may be of as great or greater interest. Special 

 reports on such features are particularly valuable. 



8583. Photographs 



Photographs of field activities, personnel, and equipment, particularly those that 

 illustrate actual survey operations, are of considerable value, and no opportunity to 

 obtain them should be neglected. 



Negatives are preferable to prints. Personal negatives may be forwarded to be 

 copied and returned to the owner. 



Negatives or prints should be submitted separately and not made a part of a 

 special or season's report. Each photograph should be accompanied by Form 623-4, 

 Photograph History. (See also 1591.) 



8584. Weather 



Weather is a major factor in the quantity and sometimes in the quality of hydro- 

 graphic surveying. Where a party is operating in a remote region, about which there is 

 comparatively little of record concerning the weather, the experience of the party 

 should be furnished in the form of a special report, which may be of aid to others 

 working in the same locality. Likewise, similar reports should be furnished for seasons 

 when abnormal weather conditions are encountered in comparatively well-known 

 areas. (See also 1453.) 



8585. Scientific Knowledge 



Officers surveying in remote regions should be alert to their opportunities to con- 

 tribute valuable information to other branches of science, such as geology, anthro- 

 pology, volcanology, and glaciology, among others. , Such information should always 

 be furnished in a special report. 



859. Reports Required From Hydrographic Parties 



For convenience a list of the miscellaneous reports required at various times from 

 the hydrographic parties is furnished below, with the form numbers, if any, and 

 references to the places in this Manual where the requirement is mentioned. (See 

 also 8351.) 



ANNUAL 



Name of Report Form No. Reference number 



Progress sketch Tracing cloth 8513. 



Statistical report iV/-1133-5 .-. 8516 and 156. 



