UNCLASSIFIED 
Security Classification 
DOCUMENT CONTROL DATA-R&D 
(Security classification of title, body of abstract and indexing annotation must be entered when the overall report is classified) 
1. ORIGINATING ACTIVITY (Corporate author) 2a. REPORT SECURITY CLASSIFICATION 
UNCLASSIFIED 
U. Ss. NAVAL OCEANOGRAPHIC OFFICE 
SeRePORT Tinloe 
AN EVALUATION OF THE 1965.0 EPOCH, H.O. 1706 WORLD MAGNETIC VARIATION CHART 
4. DESCRIPTIVE NOTES (Type of report and inclusive dates) 
° 
Technical Report 
5. AUTHOR(S) (First name, middle initial, last name) 
Donald W. Hill 
June 1968 306 2 
Ba. CONTRACT OR GRANT NO. 9a. ORIGINATOR’S REPORT NUMBER(S) 
b. PROJECTNO. 682=FB-DAX TR No. 207 
c. HF 003-03-01 B-01 9b. OTHER REPORT NO(S) (Any other numbers that may be assigned 
this report) 
d. 6.22.05.01.2 
All distribution of this publication is controlled. All qualified DDC users shall submit requests 
for copies to the: Commander, U. S. Naval Oceanographic Office, Washington, D. C. 20390 
Attn: Code 40. 
- SUPPLEMENTARY NOTES 12. SPONSORING MILITARY ACTIVITY 
U. S. Naval Oceanographic Office 
- ABSTRACT 
An evaluation of the 1965.0 epoch, H. O. 1706 World Magnetic Variation Chart 
is performed by direct comparison of charted and observed values. Results of this 
study provide an estimate of chart reliability based on the correlation of the com- 
puted spherical harmonic surface and individual field data values. 
DD ‘OP"..1473 (Pace 1) UNCLASSIFIED 
S/N 0101-807-6801 Security Classification 
