THE PACIFIC OCEAN. 



139 



The longitude of the three fevcral places is deduced from 1777- 

 the mean of 145 fets of obfervations made on fliore ; fome 

 at one place, and fome at another ; and carried on to each 

 of the flations, by the time-keeper. As the fituation of thefe 

 places was very accurately fettled, during my former voy- 

 ages, the above obfervations were now made chiefly with 

 a view of determining how far a number of lunar ob- 

 fervations might be depended upon, and how near they 

 would agree with thofe made upon th? fame fpot in 1 769, 

 which fixed Matavai Point to be in 210' 27' 30". The difl'er- 

 ence, it appears, is only of 5' 2"; and, perhaps, no other 

 method could have produced a more perfeft agreement. 

 Without pretending to fay which of the two computations 

 is the neareft the truth, the longitude of 210' 22' 28", or, 

 which is the fame thing, 208° 25' 22", will be the longitude 

 we fliall reckon from with the time-keeper, allowing it to be 

 lofmg, on mean time, i,"6g each day, as found by the mean 

 of all the obfervations made at thefe iflands, for that purpofc. 



On our arrival at Otaheite, the error of the time-keeper 

 in longitude was, 



C Greenwich rate, 1° j8' 58" 

 ^ ( Tongataboo rate 0° 16' 40" 



Some obfervations were alfo made on the tide ; particu- 

 larly at Otaheite and Ulietea ; with a view of afcertaining 

 its greatefl rife at the firil place. When we were there, in 

 my fecond voyage, Mr. Wales thought he had difcovcrcd, 

 that it rofe higher than I had obferved it to do, when I 

 firft vifited Otaheite in 1 7G9. But the obfervations wc now 

 made, proved that it did not ; that is, that it never rofe 

 higher than twelve or fourteen inches at mofl. And it was 

 obferved to be high-water nearly at noon, as well at the 

 quadratures, as at the full, and change of the moon. 



T 2 To 



