NavList:

I'm looking for theoretical articles discussing air navigation, specifically bubble sextant corrections. There seems to be almost nothing written in the modern era, and the articles that were written in the 1940s and 1950s all appear to be hiding behind paywalls. Has anyone seen a collection --besides NavList, of course!-- of articles or other resources in the theory of bubble sextant corrections and sight analysis?

Secondary question: I found what appears to be a set of PowerPoint slides talking about a rhumbline correction. I think I understand what that is: flying on a rhumbline necessarily implies an acceleration towards the near pole, and that acceleration would move the bubble at a high enough speed, but is there another name for this?

Back to the main question, here's a specific article I'm interested in reading:
"Altitude Corrections for Coriolis and Other Accelerations" by D.H. Sadler, Journal of Navigation, vol. 1, issue 1, January 1948. The extract, which I assume is from the opening paragraph of the article, reads:

Some apology, or at least an adequate excuse, is needed for resurrecting a theoretical treatment of the effect of coriolis acceleration on observations of altitude made with a bubble sextant. Such an excuse is provided by the recent publication by Dr. J. J. Green of an article suggesting that the correction table (Z-correction) given in both the British and American Air Almanacs (and in many other Air Almanacs) is incomplete. In a reasoned letter to the Editor of Navigation, Dr. G. M. Clemence, Director of the American Nautical Almanac Office, has given a simple and straightforward explanation of the two separate and distinct causes for the deviation of the zenith as indicated by the bubble of a bubble sextant; and he has further justified the present practice adopted in the almanacs. Considerable interest has, however, been aroused and it seems opportune to give a previously unpublished general derivation of the theoretical correction, together with a brief discussion of the difficulties of practical application.

That's a great opener! :) Can anyone find the article, internet or real world? I can't locate an online copy.

Thanks,
Frank Reed