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On Feb 9, 2006, at 8:40 PM, Bill wrote:

> Ken wrote:
>
>> But someone made it (perhaps only for dramatic effect), so
>> I still want to pursue it a little further.  Several posts agreed
>> that it
>> was not perilous since he was 31 min west of his DR, etc..  But, has
>> everyone missed this, as my reading puts him 31.8min EAST (or
>> closer to The
>> Smalls light, and the rocks), or am I wrong?  Is it reasonable to
>> make a
>> case that being closer than he thought was courting disaster had
>> he not
>> discovered the LOP?
>
> Not George, but here is my two cents worth:
>
> It is a tough read, and I find it somewhat ambiguous.  Printed out
> the chart
> from Bowditch so I could play with it.  My measurements put his
> 10am DR
> approx. 41' longitude west of Small's light. What is shown as the
> 10am DR is
> indeed 40nm from Tusker light, and roughly 27+nm from Small's light
> as the
> crow flies.  The text does state that the time sight put him 15'
> longitude,
> or 9 miles further east than his DR, so his sight put him 31'
> longitude west
> (approx 19nm) of Small's light. (My comfort level would definitely be
> decreased by the time sight.)
>
> Further, it is difficult for me to tell exactly how much ground he
> covered
> after his 10 AM sight until the elapsed time stated to complete the
> leg to
> the light.  While the line of position may have become clear at
> "once" (once
> the calculations were done), how long did it take to make them?
> All I can
> tell for sure from the account is that "...the ship was kept on her
> course,
> ENE,..."  So I presume she was sailing ENE after the sight and while
> calculations were being made.  Once the LOP was clear, she then
> made the
> light in less than an hour.
>
> Unfortunately there is not enough information in this account to do
> time
> time/speed/distance calculations, but a SWAG says they didn't cover
> 27+ nm
> in the time it took to do the calculations, plus less than an hour
> more of
> sailing.
>
> From the account, and the SWAG, it would appear that Ken's
> reasoning is
> headed in the right direction.
>
> Bill


Well yes, he was courting disaster had he kept his course up to the
moment of spotting Small's light, lacking the LOP.  But lacking the
LOP, I expect that he would have stood off or similar, and lost time.

   

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