Gl 



and furnishing a graphical method of solving most of the 

 problems of navigation, was also prepared and engraved. 



Investigations were made of numerous reported dangers, 

 many of which were found to have no existence and were 

 removed from the charts, while the geographical positions 

 of others were discovered to be wrong. 



Notwithstanding the adoption of the policy of limiting the 

 tedious and unsatisfactory method of correcting charts by 

 hand to charts that required but small changes, the rapid 

 extension of the field of usefulness of the Office brought a 

 correspoudiug increase in the sources from which informa- 

 tion was obtained, so that the work of hand-correcting was 

 still one of considerable magnitude. „ , . 



° Catalogues 



Examinations and catalogues were made of original re- made of original 



° ° surveys. 



ports of surveys and other papers containing hydrographic 

 information that had accumulated from year to year in the 

 Office. • 



The popularity of the Meteorological Charts of the North 

 Atlautic kept the small force of officers that could be detailed 

 for the duty constantly occupied in the labor of collecting and 

 preparing data for their construction, while the work on 

 those of the South Atlautic and Indian Oceans was neces- 

 sarily suspended for want of sufficient force to carry it on. usefulness of 



The branch offices, now firmly established upon a work-IJ 1 ^ branch of- 

 ing basis, proved reciprocally valuable both to the main 

 Office and to the commercial world. They served as agen- 

 cies for the dissemination of hydrographic matter of every 

 kind, and became veritable bureaus of nautical information 

 for merchant captains, ship-owners, marine insurance com- 

 jianies, and persons of every class engaged in ocean navi- 

 gation. The officers in charge of them were brought 

 directly in contact with sea-faring men and were thus 

 enabled to collect and forward to the main Office a vast 

 amount of data for the benefit of the commercial world that 

 otherwise might not have been secured. Every vessel that 

 entered a port was boarded by an officer from the local 

 branch office and inquiries were made regarding the general 

 weather the vessel had encountered on her voyage, the 

 limits of the trade winds, location of ice, fogs, water-spouts, 

 wrecks, drifting buoys, &c. 



Merchant captains evinced their appreciation of the ob- Merchant cap- 

 jects of the Office by their uniform courtesy and their wil- appreciation of 

 lingness in all cases to furnish every assistance in their oaicT" 



