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Thank you, Frank. I looked in my 1933 Bowditch and found the "double entry" 
hav/loghav table - 94 pages, because it goes thru 12 hours by one second 
steps.

The modern hav/loghav table is table 34 in my 1975 Vol II of Bowditch. It also 
goes thru 180* but in 1' steps, so it gets done in 35 pages.

This ongoing exploration (ok, exhumation, to keep the archaeological metaphor 
going) of a relic is proving entertaining and absorbing. Reminds me of a time 
I was expanding on sailing and celestial to my granddaughter and when I wound 
down, she said, "I get it, you've become a fossil in your own time."  

Interesting - a relic digging relics.  :-)

Thanks again for the heads up.

Hewitt


Sent from my iPad

On Jan 2, 2013, at 3:40 PM, "Frank Reed"  wrote:

> Hewitt, you wrote:
> "Great going, Greg. Many thanks for this. Is there a way to download so it can 
> be printed? I don't have a printer, so need to put it on a memory stick and 
> take to a copy shop."
> 
> There's a good chance you already have the equivalent in a familiar book. If 
you have a copy of Bowditch from about 1910 to 1962 (not sure on the exact 
date limits), it has Table 34 which is tables of haversines and log 
haversines. Because of the "weirdness" of Martelli's mixed up tables, there's 
an odd constant to deal with, but you can get any value in the table Greg 
calculated simply by taking the loghav value from Table 34 of Bowditch and 
subtracting it from 11.0334. Every number in Greg's newly calculated table is 
just 11.0334 minus the corresponding value from Bowditch Table 34. As I noted 
previously, Martelli's tables can be easily re-engineered without all his 
weird constants (no 11.0334 after that) and when you're done you'll find that 
the tables are almost all already present in mid-century editions of standard 
navigation manuals. Notice also that the hav(t) tables in editions of 
Bowditch before the big overhaul released in 1958 are double entry: you can 
look for the LHA in degrees or in hours and minutes of time. By the 1950s, 
actual time sights, requiring the entries in hours and minutes, were 
"officially" if not quite over and done with in practice.
> 
> -FER
> 
> 
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