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Hi George

I have created a spreadsheet which computes the reductions in the same manner 
that Worsley did.  I used 6 place logarthmic values instead of 5, since I 
found the rounding was not identical to the values he used. Further, the 
spreadsheet computes the reduction with the characteristic present in the 
nautical sense.  I have attached this spreadsheet for the general amusement 
of the crowd!

One great interest in this is the correction of the transcript.  Since the 
images of the log are muddled, it is difficult to make out numerical values 
at times and some of the notations that I injected into the transcript may 
just be artifacts of the image.  I have corrected the log for about 4 digits 
and 3 notations as a function of the spreadsheet.

The next interest would be in the recreation of the 4 May 1916 data, because 
the log image only offers partially readable data.  I did not correct the 
transcript here because it is still subjective, but I can safely assign some 
digits.  More to come on this later.

One interesting point came in the reduction of 26 April 1916.  The numbers 
just didn't seem to make sense, until I realized that the arc-haversine value 
he obtained, he mentally performed a supplement computation to get the time 
from noon.  The arc haversine yields 53 minutes 49 seconds, but he wrote down 
23 hours 6 minutes and 11 seconds.  Further, when he performed the 
subtraction of arc-haversine time from chronometer time, he added 24 hours to 
2.28.21, so his result was 3.22.10.  This was a puzzlement until I came to 
the realization and is now clear.

The updated transcript is attached.

Best Regards
Brad

File: 
Worsley-Method.xls

File: 

   



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