Comstock, George Cary, 1855- **E.5118.49 The Sumner line or line of position as an aid to navigation. Ist edi- tion. — New York. John Wiley & Sons, Inc. 1919. vi, 70 pp. Maps. Dia- grams. Tables. 1514 cm.
4d “f v an) This card was printed at the Boston Public Library, January 20, 1yzt.
M708 — Line of position.