77 



The result is one of much interest to the progress of science, and 

 of special importance in the longitude operations of the Coast Survey. 



The value apparently attributable to wave time, is too great to be 

 neglected in telegraph operations for longitudes intended to be used as 

 data in connexion with geodetical measurements. A more extensive 

 series of operations, with more complete mechanical arrangements, 

 will be undertaken in the course of the cominoj season. 



Very truly yours, 



A. D. BACHE. 



Dr. R. M. Patterson, 



Pres. American Fhilos. Society. 



Table of Relative Distances. 











Relative miles 





Star Signal 



Receiving 





traversed by 



No. 



Station. 



Station 

 Compared. 



Wave Time. 



Clock and 

 SignalWaves. 



1 



Philadelphia 



P — w 











2 





P — c 











3 





P — N 











4 





W — C 











5 





W — N 











6 





N — C 











7 



Cambridge 



P — W 



A + B + C — D 



150 



8 





P — c 



2 B + 2 C 



900 



9 





P — N 



2 B 



400 



10 





W — C 



— A + B + C + D 



750 



11 





W — N 



_A + B — C + D 



250 



12 





N — C 



2 C 



500 



13 



New York 



P — W 











14 





P — c 



2B 



400 



15 





P — N 



2 B 



400 



16 





w~c 



2 B 



400 



17 





W — N 



2B 



400 



18 





N — C 











