from to 9. These digits indicate the difference between maximum 

 and minimum values of one of the magnetic vector components occurring 

 during specified 3-hour time intervals. Table I lists the gamma ranges 

 for the K-index values at Fredericksburg and Hartland. 



The K-indices from each observatory are given in graphical form 

 in Figures 3 and 32 appearing at the beginning of Parts I and II 

 respectively. It should be noted that the records from these two 

 observatories represent geomagnetic conditions existing within only 

 a few miles of their respective geographic locations. These records 

 can, however, give an indication of conditions that probably occurred 

 in areas adjacent to the observatories. 



Figure 3 shows that during the November 1961 crossing, the K- 

 index values from Fredericksburg exceeded index 3 (40 gammas) for only 

 one 3-hour interval, 0600-0900, 20 November. During this interval, 

 however, the survey ships were nearer to Hartland than to Fredericksburg. 

 The Hartland values never exceeded index 3 during the entire time of 

 the westbound crossing. 



Figure 32 reveals that geomagnetic conditions were more disturbed 

 during the March 1962 crossing. On 5 and 6 March, K-indices exceeded 

 index 3 at both observatories. The \a lues from Hartland again exceeded 

 index 3 on 10, 12, and 13 March. At no time during westbound or east- 

 bound crossings did the K-index values of either observatory exceed 

 index 5 (120 gammas). It is assumed, therefore, that no significant 

 temporal anomalies are incorporated in the magnetic data profiles. 



