I have recently been handed a small book entitled “Sumner’s Method for Finding a Ship’s Position,” by Rev. G. M. Searle, Director of the Observatory, Catholic University, and formerly a Professor in the Department of Mathematics at the U. S. Naval Academy. The book is published by D. Van Nostrand Co., New York (price fifty cents). It provides a means of computing the intersection of two Sumner’s lines without solving for each line separately—a method that I have not before seen used and which seems to me to be more simple than any other method of computing intersections with which I am familiar. I believe that navigators who desire to get a fix from two observations with a run between will find this method to be advantageous, and this article is submitted with a view to calling their attention to it.
Searle's Method of Finding a Ship's Position
By Lieut. Commander Harris Laning, U. S. Navy