The International Maritime Organisation Convention on Standards of Training, Certification and Watchkeeping describes the levels of knowledge agreed by maritime nations to be met by seafarers for the issue of certificates of competency. Certificates may be issued for unrestricted service and for near coastal service only. It follows that with regard to navigation the level of near coastal work is less extensive than that of unrestricted sailing. The volumes give a measured coverage of the subject matter designed to provide for all grades from limited coastwise requirements to ocean going master.

Volume II commences with the use of logarithms and trigonometry in navigational problems. Plane and Mercator sailing is dealt with before proceeding to the celestial sphere and the principles of celestial navigation. There are extensive worked examples and examples for exercise on finding the error of the compass by celestial bearing and on obtaining position lines by celestial observation. The practical use of position lines found by all means is treated at length.