I have my hands on a copy of Davis & Tozer that I believe is probably the same version Q posted at the top of this thread. It is the "Revised Edition," not the Third. I believe it (or at least the one I have) can be dated to around 1927 -- unless it is a reprint of that edition. Some of the interesting things are that W.K. Hill, in his preface, makes reference to "the lover of folk music" and to "folk songs." I don't know for sure, but that doesn't sound to me like 1906 talk. And he says "As long ago as the year 1887..." in reference to the first edition. That sounds too distant a past for 1906. He says that aircraft was only a dream back then, but that now there is a "conquest of the air" -- which suggest tome after WWI.

The back of the book has ads for other publications. (Again, I suppose this could be a reprint, so, FWIW:) One add is for Sampson's _Seven Seas Shanty Book_ which came out in 1927. Also an ad for Davis & Tozer's own book, with a note that the original had appeared almost 40 years earlier.

Ads for other musical arrangements of chanties, too, always with the redundant phrase "sea shanties" that one imagines had become popular by that time as they were adopted as "folk" music.