J. E. Hilgard—Magnetic Declination in the United States. 175 
secular variation of the magnetic declination in the United 
States were available, without which it would have been diffi- 
cult to reduce the observations to a common date, with some 
approach to accuracy. His latest paper on this subject, printed 
recently, will be found very useful for reference. 
For a separate publication, it will probably be convenient to 
print Mr. Schott’s map, illustrating the annual change, on the 
obverse side of the chart of magnetic declination, in order to 
make the sheet available for use without the aid of an explana- 
t. 
tory tex 
J. KE. HILGARD, 
Assistant Coast and Geodetic Survey. 
To Carine P. Parrerson, Superintendent. 
U.S. Coast and Geodetic Survey Office, Washington, D. C., July 1, 1879. 
tion in the United States, etc., by C. A. Schott. Appendix 
0. 8 to Coast Survey Report for 1874, third edition, 1879. 
pee local peculiarities that have not been ascertained. 
or the interior States the information is very scanty, or 
. >. € annual change is expressed in minutes of arc, a + sign 
indicating increase of westerly or decrease of easterly declination. 
Locality. Annual change. Locality. Annual change. 
ae coast of Saree Took S. FS ag West Virginia....--..------ + 
ting at te ene ee po +3 N. Carolina, §.Carolina,Georgia +34 
Sad Hampshire _.__...__- +34 Florida, northern part - ---- -- +3} 
Nisei Se eempgtage hak 54 Florida, southern part ---.--- + 
7 sachusetts, eastern -. +24 Alabama, Mississ., Gulf coast of +34 
Rhod stern part._. +3 to 4| Louisiana, eastern part -----. 
tae Island and Connecticut. +3} iana, western coast .-.-- +2 
ee York, Long sland, ..___ +24 Tetas, cast OF oS 5 ke +2 
Rou. borthern and west’n part +4} as, southwestern part .... 0 
P oh Jersey WoNeu woo Seue cyae +3 ColaetGiucoren se bes +2f 
Ohie ytvania ate cere +38 Tale es ee +4 
Ty, je oe ES Sn cae +24 New Mexico and Arizona.... 0 
7 unessee, eastern part 2: +24 California, coast of...------- —lt 
Samira » Western part______ +2 Oregon, coast of _.....-.---- —2to2d 
sr adag nN Sone ee Songs a9 Washington Territory, coast of —2}to3 
Ware,Maryl’d, and Virginia +3 
