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The predicted lunar distance tables were dropped  from the British Nautical
Almanacs in 1907 and from the American Nautical  Almanacs in 1912. But
instructions on computing and using them were included for  quite a while after those
dates in appendices to the almanacs.

The  "American Nautical Almanac" included an appendix through 1933 that
explained how  to calculate a lunar distance if a navigator chose to use them. It
gave two  simple methods for calculating the distance, one that gave the cosine
of the  distance which was appropriate for large angles and the other that
produced the  sine of the distance which was good for small angles. The appendix
was updated  with fresh examples every year. There was no advice on clearing
a measured lunar  in the American almanac.

The British "Nautical Almanac Abridged for the  Use of Seamen" included an
appendix through 1919 or 1924 or perhaps 1928  (haven't found out for sure yet
and secondary sources disagree) that explained  how to calculate a predicted
lunar distance using versines, haversines, or log  haversines. But this appendix
went much further than the one in the American  almanac. It also included
good, basic instructions on the general principle of a  lunar distance and
described the calculations necessary to clear a lunar using a  method closely
related to Airy's excellent method. This appendix suggested  shooting lunars with
the Sun, the bright planets, the usual nine lunars stars,  and also Castor,
Betelgeuse, and Procyon as good options for lunar  distances.

So why were they keeping this up so many decades after lunars  had fallen
into practical disuse? In short, for the same reasons we think about  doing
lunars today. The introduction to the appendix in the British Abridged  Nautical
Almanac says it perfectly: "there is probably no better method of  becoming an
expert observer with the sextant than by practising this  observation".

-FER
http://www.HistoricalAtlas.com/lunars

   

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