85 



ship have auy advantage over the ' Kent,' but rather the reverse." The 

 "Kent" was telegraphed in the Downs one day before the "Marco Polo" was 

 sighted from Holyhead — the distance to the Downs being 165 miles or 

 thereabouts greater than to Holyliead. This is one example of the great 

 value to be attached to superior skill for conducting composite sailing, 

 in which both captains were possessed of more than the ordinary amount 

 of ability. If we judge from Captain Coleman's account, the " Kent" is 

 a ship that should have made the voyage from Australia in ten days less 

 than the " Marco Polo ;" instead of which, allowing one day for the 

 difference of distance of the Downs and Holyhead, still the " Marco 

 Polo " accomplished the run in three days less time. 



When first the admiralty did me the honour to publish my tables, I 

 anticipated a greater amount of improvement from its application to 

 what I denominated windward great circle sailing than from any other 

 of its practical uses. Although with respect to composite sailing it has 

 been emplo3'ed with a degree of success surpassing my most sanguine 

 expectations, still, in working a ship to windward, in very few instances 

 am I awai'e of its having been brought into application. The case I 

 have just given of the " Marco Polo" leaving Melbourne is a fine illus- 

 tration of this application, and is in fact the idea which suggested itself 

 to the mind of Captain Forbes when he made the boast, which has 

 subjected him to animadversion, that he would turn a foul wind into a 

 fair ; for practical purposes, he has kept his word. Windward sailing [ 

 thus describe : — 



When a ship cannot, on account of adverse wind, sail directly to her 

 port, she obviously ought to be put on that tack by which she nears her 

 port by the greatest proportion of the distance sailed. It is also evident 

 that she must do this when her track deviates by the least amount from 

 the direct line which connects her with her destination ; or, in other 

 words, when she is put on that tack which deviates less from the true 

 course than the other tack. In adopting this rule it must however 

 be especially borne in mind, that the true course alone can serve as a 

 guide in choosing the tack ; and that the great circle, and not the 

 rhumb, is this true course. But, since the mariner is more conversant 

 with the rhumb than the great circle, too much attention cannot be 

 directed to the importance of making this distinction between these two 

 courses in connection with windward sailing. In crossing the Pacific, 

 the rhumb course frequently deviates four points from the true course : 

 under such circumstances it is impossible that the mariner can navigate 

 his vessel with advantage if he fail to make himself acquainted with 

 the great circle course. 



