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Bruce, you wrote:
"I've know for decades that along the New England coast the high and low tides occur about 50 minutes later each day. I've also been aware, more or less, that moon rise and moon set change from day to day. I just never realized the rise and set move later about 50 minutes each day. AHA.....says moi."

Yes, indeed. You can predict the high and low tides with reasonable accuracy just by asking where the Moon is. For example, near Mystic Seaport, low tide occurs three hours after the Moon's meridian passage. This time difference can be any number. Popular science accounts and even textbooks frequently get this wrong and take the equilibrium tide model too literally. It is not high tide when the Moon is on the meridian, except by chance. For any location along the coast, there is some time offset which will work reasonably well in locations that have "normal" semi-diurnal tides (but don't try this on the California coast or anywhere else where the tides are "mixed"). Nautical charts used to include short tables giving these tide offsets, historically sometimes called the "establishment of the tide". I'm attaching one from a southern New England chart published in 1897 (and a reminder: there's lots of fun in the online historical chart collection --US only). You can look up or figure out or just observe this tide offset time for any coastal location. Note that these offset or "establishment" times are really correct for the day of spring tides (usually a day or two after New Moon or Full Moon). On other days the solar and lunar tides interfere with each other (in a predictable way that's not hard to learn) and lead to the "priming" and "lagging" of the tides.

And you wrote:
"The above musing was prompted by Figure 16-1, page 89, in John Letcher's book Self Contained Celestial Navigation with H.O. 208. I've studied this figure in the past and never thought about it too much. The figure shows a rising moon with a higher position ,Ho, on successive evenings at the SAME local time. Really?"

Yes, that looks right to me. Same local time. If you went outside at exactly 6:50 pm, for example, over the past few days, you would have seen the Moon in very much those positions on successive evenings in twilight.

-FER

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