H.M.S. Dryad's memorandum (Journal, 9, 444) speaks of ‘only those tables required’. But what this word ‘required’ does or should mean could be debated ad infinitum. The main division comes as between a set of tables intended to be an instrument of practical navigation and one intended to be an instrument of technical education, and the dividing line between the two would be a very blurred and disputable one indeed. My own set of nautical tables came into existence because I was convinced at the time that a set of tables, ‘streamlined’ for sea use was urgently needed, and in so far as logarithmic methods may be still used I still consider that my first edition was a better instrument of navigation than any of the four later ones. But whereas I knew that I wanted such a set of tables for my own use, and was of the opinion that everybody else did (or should), I became aware that I was in a comparatively minute minority. In fact it became slowly and painfully borne in upon me that something like 90 per cent of all navigators would use all their sea-going lives the tables they were first taught on. This meant that I had to consult the schools and examining authorities and include all their academic needs, and so my streamlined volume soon began to develop a corporation. I did, of course, try again with my Four-Figure Navigation Tables, but that is another story.