90 



HyBEOGBAPIiy. 



[Sect. III. 



once for all, that the longitude of a place, by chronome- 

 ter, from Greenwich^ should never be given without the 

 accompanying longitude from which the deduction of the 



made ; in short, that clironometers should 



meridian was 



be referred to only as a measure ^^f differences. 



Coral Islands. 



31. Should coral islands be fallen in with, determine 

 their position, extent, and map their outline; fix the 



openings into the lagoons, and describe their general 

 appearance, whether wooded or not, and whether any 

 high clumps of trees (distinguishing the palms) he con- 

 spicuous upon them, and at what part ; you should then 

 particularly notice the slope of the coral on both the 

 outside of the island and the inside, and run off hues of 



soundings in various 



great a depth as you can reach, and at each cast par- 

 ticularly note the bottom, whether it be living or dead 



depth at which live coral is 



coral 



note the 



brought up : the existence of livin 



1 



a point of interest* A 



coral at great depths 

 fixed to the lead will 



often bring up specimens of coral which might otherwise 

 be missed. 



Point out the place of the anchorage in the lagoon by an 

 anchor, and state whether vessels can sail in with the trade 

 wind or not, and the best time for going in, for in niaiiy 

 of these Islands there is so strono: a current running out 



through the channel after the trade wind has set m, in 



the morning, as to render it imprudent to attempt the 



pas 



sides, and the land breeze has commenced, that the P^^ 





and in some it is only after the sea wind su^ 



ft 



\ 



r 



Sect. 



1 



breez 

 occas 



into 



obse' 



chan: 



sidei 

 spots 

 upon 



Ci 



alltl: 



and 



mark 



32 



point 



pract 



point 

 we s 



are t 



the 



rangf 



aido 



tiguo 

 featu: 



whicl 



\ 



our 



to 

 of 



F 



ai 



ping, 

 may, 



