ERRATA 



Page 356, line 10 from bottom : 

 Replace "essential" by "desirable." 



Page 356, line 5 from bottom to line 2 on page 357. — Erase, 

 and substitute : 



The object should be chosen as near 90° as possible from 

 the sun, and the altitude of the latter should not be more than 

 20° and near the prime vertical. 



Page 357, line 4 from top : 



Replace paragraph " First . . . mountain top " by " First, 

 when the object whose bearing is desired has no appreciable 

 altitude, and secondly, when it has a sensible altitude, as a 

 mountain top, or has a depression due to the height of eye of 

 the observer, as an object on the sea horizon." 



Page 357, lines 9 and 10 from top : 

 Delete " on the horizon." 



In margin amend to " Object with zero altitude." 



Page 357, Example, line 1 {in brackets) : 

 Amend " on horizon " to "' with zero altitude." 



Page 357, Example, line 5 : 



After "Pine a " delete " on horizon." 



Page 360, tise of Polaris, line 2. — Add : 



the most favourable conditions being a low latitude and object 

 bearing nearly east or west. 



Page 360, line 6. — Erase the word " large," and substitute 

 " as nearly as possible 90°." 



