BOOK
II
1797
October
Variation for
Azimuths with two compasses,
Ther. 62° to 70"
Mean latitude of the south point of entrance,
Mean of 37 Jets of distances, taken before our arrival,
Mean of 42 Jets on each side of the moon, at anchor,
Mean of 20 Jets, taken after leaving the harbour,
35°
129°
128°
129°
8'
2'
24'
46'
18'
0"W.
0"N.
18"E.
49"
15"
The mean of the 99, reduced by the watch, will make 129° 7' 7", which is taken for the true longitude of Tchosan harbour.
By single altitudes taken on shore, between the 13th and 21st of October, the watch N° 45 was slow. for mean time at Greenwich 0 h. 12 m. 33s.2., on the 2lst of October at noon; and was found to be losing per day 9".80. on mean time. On the 13th, the watch shewed the longitude, at anchor, by Endomo rate, 130°26'21"E.;by Macao rate, 128° 40'33" E.
As it appears the watch goes so irregularly, or that the rate acquired at Endomo harbour is subject to some error, I have shewn daily the longitude by Macao rate, correcting its error in longitude at Endomo, which makes it agree better with all the observations we have made since leaving Volcano bay.