NavList:

Brad Morris, you wrote:
"It appears that the list isn't comprehensive, or perhaps Worsley had his own bookshelf.  Where is Nordenskjold's Antarctica?  Where is the Nautical Almanac (presumably the British version)?"

That's right. It appears to be Shackleton's "light reading" bookshelf. I would guess it was photographed because it told a story about Shackleton's attitudes and interests. Photographing the navigation books would have been akin to photographing the owner's manual of your car. 

By the way, I found some links for resources which Robin was looking for (private comm). Here is the American Nautical Almanac for 1916 and here is the British Nautical Almanac and Astronomical Ephemeris for 1916. The British "Abridged Nautical Almanac" already existed in 1916, but it would not have been unusual for a navigator on an important mission to carry the full volume. Here's the full search results for reference, with multiple copies of each.

You asked:
"Would you mind clarifying the term "took departure from Camp Wild" as it appears in logs?  I vaguely recall that this may mean the observation is out to sea when the landmark is still visible (and therefore not taken on shore at Camp Wild)."

Yes. Think of it this way: it indicates the end of piloting navigation, the end of navigation in reference to shore features, and the beginning of ocean navigation by simple dead reckoning and celestial when possible and convenient. It was up to the navigator to decide when this occurred, but it generally was supposed to indicate the last reasonably certain terrestrially-derived position.

It's important to remember that there were no laws to the practice of navigation. And there were also no absolutes in terminology. For example, I think you're reading too much into that "s" on the end of "chronometers" in one instance. Maybe Worsley sometimes thought of his watch (or whoever's watch) as "nearly a chronometer". Perhaps in discussions with Shackleton later he agreed that this was misleading. History isn't like mathematics; one exception does not disprove a theorem. People contradict their own words. And navigational procedure is always an individual's singular practice, evolving and shifting as circumstances require. This was far more the case in the heyday of astronomical navigation a hundred or two hundred years ago. It's the late 20th century that converted celestial navigation into something rote, formulaic, and militaristic in its regimen.

Frank Reed

PS: Yesterday, after teaching my physics class at Northeast Maritime Institute in Fairhaven, I was sitting in one of the libraries next to the Joshua Slocum collection between a model of Slocum's "Spray" and a model of the "Charles W. Morgan", and in the main classroom next door, I could hear that they were watching a video. It was some documentary... I could catch a few words here and there... "weather..." and "ice..." and then I heard plainly "Shackleton". Aha! Too funny.