26 THE ANTARCTIC MANUAL. 
(b) As far South as possible between the Longitude of 160° W. 
and 115° EK, 
(c) Especially in the region comprised between Latitudes 65° S. 
and 80° S., Longitude 160° E. to 160° W. 
(d) Also between 45° S. and 60° S., and between the Longitudes 
120° KE. to 140° E. 
(c) From Melbourne to Cape Horn, between the parallels of 
50° 8. and 60° S. 
(1) It is necessary before leaving England that the ship should 
be swung for deviation of the compass at the Standard and Fox 
positions, the coefficients X and pw, and the constants g, being deter- 
mined at the same time. 
It is recommended that these initial observations should be made 
with great care, the resulting data being of great importance in 
showing the actual amount of disturbance caused by the iron in the 
ship, and the prospect in that respect for the future. Spithead is 
suggested as an excellent place for carrying out these observations. 
(2) It is not necessary to swing the ship for observing the 
deviations of the Dip and Total Force from the normal, but to 
compensate for the omission of that laborious operation on different 
occasions, the ship should be swung for deviation of the compasses 
on the eight principal points as often as it can be conveniently done. 
Each swinging should occupy about one hour. The Fox compass 
must be invariably compared with the Standard compass when 
swinging. 
(3) When the Fox circle is employed at sea the method of 
observing the deflections by grains, as well as by deflectors, should 
be adopted when possible, as by this means changes in the moment 
of the deflectors can be detected. 
(4) The declination or Variation should, when practicable, be 
observed twice in the day at sea, and when the sun’s altitude is 
below 30° 
(5) The Dip and Force should be observed daily at sea. In the 
high Southern latitudes the observations should be repeated during 
the day, the hours between 9 and 11 am., and 5 p.m. and 7 P.M., 
being recommended. The ship should be carefully steered during 
these observations, any departure from the course being notified to 
the observer in the observatory by an assistant stationed at the 
Standard compass, in order that the Dip circle may be adjusted to the 
meridian if required. 
(6) Charts of the Declination and of Total Force are supplied. 
They will probably be liable to large corrections as the Magnetic 
