NavList:

Greg R. wrote:

--- Lu Abel <lunav@abelhome.net> wrote:

  

I suspect very strongly the arrangement of data was based more on
the needs of the computational algorithms used to compute the tables
than for convenience of the navigator.
    

Possible... but I've still got to ask the obvious question: Assuming
they were using the same formula that we use to solve the navigational
triangle today (and I don't know if that's the case or not), it doesn't
seem like it would be any more difficult to solve a series of them
(i.e. a table page full) with any one of the variables held at a
constant value vs. another of them (i.e. holding the LHA value constant
for a page as 229 does vs. holding latitude constant for a page as 249
does).

For a moment, let's remember that the original meaning of "computer" was "someone who calculated things."  This list regularly discusses pre-1950 tables for sight reduction, lunars, and almanacs.   These were computed by hand.  Mathematicians had worked out wonderful ways to compute things using a minimum number of time-consuming and error-prone calculations.  One way was to reuse data from a similar previous calculation.   I have absolutely no idea how the 229 tables were actually calculated, but it is entirely possible that there was some such "re-use" of data, given the fact that the IBM 1410 was about a million times slower than the PC that you're reading this email on.  That re-use may have dictated the format of the tables.

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