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George:

Thanks for your consideration. But I don't share your difficulty with
finding the time to initiate the last set of measurements. I took the
example data while single handing a 31' ketch. It was stable enough, and
I merely raised the sextant occasionally until the sun's altitude was
close to the last one of the first run. Then I started taking the last
run. It was really quite simple. So simple that I never thought of any
problems with it. I'm reminded of a Chinese saying, "Don't tell man doing
job that it can't be done."

As to measurements around maximum altitude, I started a few minutes
before, and just kept shooting until I was sure that the maximum had
occurred. Again, not a problem. I'm willing to use your data as is, since
the real test here is longitude determination. So, if I use your three
altitudes around the maximum, and five each for the ascending and
descending runs, that's thirteen. Fair enough?

About the one minute intervals. The actual time between sights that I
recorded ranged from 32s to 1m39s. Most were less than a minute. My
students have no difficulty taking their first ever sights about a minute
apart, although I team them in pairs so that one can do the recording.
Again, I just thought that was normal.

Finally, about the time difference between LAN and maximum altitude. I
calculate that it's about five minutes, and that's not a lot in an hour.
Again, not a problem.

I was wrong about the declination. S23�26.4' is -23-26.4/60, and that's
-23.44. I was reading 26.4' as 26'40". Arithmetic is not my strong point.
That may be why I like things simple.

Thanks for your help. I hope that the above gives you all the information
that you need to simulate the data I requested.

Jim Wilson
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