rs were obtained, for the sake of expedition,
from single altitudes of the sun's upper and lower limbs, taken from a
quicksilver horizon with a sextant fixed on a stand; the time being noted
from Arnold's watch, compared with Earnshaw's time keepers before going
on shore and immediately after returning. From the altitudes of the 3rd,
4th, and 6th, in the morning, the rates of the two time keepers and their
errors from mean Greenwich time, reduced to noon there on the last day,
were as under.

Earnshaw's No. 543, fast 0h 0' 18.03" and losing 8.46" per day.
No. 520, slow 0 45 29.66 and losing 18.07" per day.

In deducing these errors, the longitude given by the time keepers on our
first arrival from Spencer's Gulph, which I consider to be equally good
with that of Port Lincoln, was used, with a correction of -1' 20" for the
change of place. The medium of the Port Lincoln rates was something
greater than that now found; which corresponded with the time keepers
having given the longitude of Kangaroo Head less on the second than on
the first arrival. This was some proof that the letting down had not
affected the rates, and tended to give me confidence in their accuracy.

The _variation_ observed on shore, with the theodolite,
was 5 deg. 48' east. Do. with azimuth compass, No. 1 with the theodolite,
was 2 deg. 58' east.

For this difference between the instruments, I find it difficult to
account satisfactorily; but it is the same way, and nearly similar in
quantity to what was observed in Lucky Bay. The true variation on board
the ship, deduced from azimuths taken at anchor two miles to the
north-east, and using the compasses No. 1 and 2, was as before mentioned,
4 deg. 13', nearly the mean of the above; but the bearings taken with the
theodolite at Kangaroo Head and Prospect Hill showed only 21/2 deg. east, as
compared with the bearings on board the ship. There can be little doubt
of the existence of magnetic substances in the lands about here, more
particularly, as I think, in Yorke's Peninsula; and there will presently
be occasion to notice more instances of their effect.

The approach of the winter season, and an apprehension that the discovery
of the remaining unknown part of the South Coast might not be completed
before a want of provisions would make it necessary to run for Port
Jackson, prevented me from stopping a day longer at Kangaroo Island than
was necessary to obtaining rates for the time-kee