Actually, a re-write of an earlier book by the well known, and late Capt. O.M. Watts, this little book has been brought up-to-date by Dag Pike, a likewise very well known navigator and author. As it must, this book gives a description of the sextant, discusses its principles, and instructs in its practical use and care. But it is packed with information! Everyone who has read it (and knows something about navigation) has nothing but praise for it. It is small enough to fit in most sextant boxes, and we recommend putting it there. SC. 2003, 104 pages. SW 0.5 lbs.