128 pp, 7 3/8" H. Green cloth with black lettering on spine, black lettering/border on front board. B&w photographs, drawings, maps (3 fold-out), formulae, tables, etc. "Prior to the year 1919 there was little occasion for long-distance air navigation: the subject has, however, become one which requires study, and the remarkable trans-atlantic flights of 1919 have shown that the art of sea navigation can with suitable modifications be applied to the air. The purpose of this little books is to show in simple lang-uage how this can best be done and how when sea-going methods fail others can be devised to take their place. The net result is that although the long experience and tradition of sea navigators forms the convenient basis on which air pilotage and navigation is founded, the latter have individuality enough to substantiate a claim for separate treatment." From the author's Preface. Contents: Introductory; General Principles; Dead Reckoning Navigation; Directional Wireless Telegraphy; Astronomical Observations; Reduction of Astronomical Observations; Appendices: Occurence of Fog; The Effect of Dip and Acceleration on the Compass; Answers to Example; Tables of Constants; Index. Light lean to book, minor browning on free endpapers, light wrinkling at top/bottom of spine, tiny ink mark and tiny edge dent on both boards. Dust jacket has light browning on spne and flap-folds, small edge tears and some very small chips, old label and faint numbers on front panel, edge wear, edge wrinkling, rubbing, protected in a mylar sleeve.