74 
A VOYAGE TO 
[East Coast. 
1S02. 
September. 
No. 543, H9° 54' 27" east. 
No. 520, 149 53 47>5- 
The mean is 7' 14" to the east of thelunars; but on using rates 
equally accelerated from those at Port Jackson to the above at Upper 
Plead, and commencing the acceleration on Aug. 15, at Keppel Bay, 
where the time keepers were found to be keeping their former rates, 
the mean longitude will be 149° 4«' 56", 6, or 2' 3", 6 from the lunar 
observations; which is therefore the presumable sum of their irregu- 
larities after August 15, or in 27,7 days. 
In fixing the positions of places along the East Coast, I have 
made use of the time keepers from Port Jackson to Port Curtis, 
without any correction. From Port Curtis to Broad Sound, the 
coast and islands are laid down from theodolite bearings taken on 
shore, combined with the observed latitudes ; and consequently the 
accuracy in longitude of the first portion depends upon that of Port 
Jackson and the time keepers, and of the last, upon Upper Head and 
the survey. These two unconnected longitudes meet at Port Cur- 
tis, and the difference between them is there no more than 5." 
From observations with the theodolite upon the top of Upper 
Head, the variation was 8° 37' east ; but on moving the instrument 
ten yards to the south-west , it was 45' less. At two other stations on 
the west side of the sound, it was 8 ° 15', and 8 ° o'; and on board 
the ship 7 0 1/ and f 46', corrected. On the east side of the sound 
it differed at six stations on shore, from 8° to 6°; and on board the 
ship was 6° 44' corrected. As general results, therefore, but subject 
to many small deviations, the variation may be taken, 
On the west side of Broad Sound at - - 8° o' E, 
On the east side - _ _ - 7 0 
At the head of the sound it was, at one station 
12 0 , at another io°; the mean, - no 
The differences between the two sides of the sound, both on shore and 
on board are nearly similar to what took place in Shoal-water Bay. 
The rise of tide and time of high water have been mentioned; 
