The personnel of the Ryan Airlines at once caught the spirit of the undertaking, and during the two months of construction the organization labored as it never had before. Day and night, seven days a week, the structure grew from a few lengths of steel tubing to one of the most efficient planes that has ever taken the air. During this time it was not unusual for the men to work twenty-four hours without rest, and on one occasion Donald Hall, the Chief Engineer, was over his drafting table for thirty-six hours. I spent the greater part of the construction period working out the details of navigation and plotting the course, with its headings and variations, on the maps and charts. After working out the track on the gnomonic and Mercators charts, I checked over the entire distance from New York to Paris with the nautical tables. The flight from San Diego to St. Louis and from St. Louis to New York was comparatively simple, and I took the courses directly from the state maps. From New York to Paris I worked out a great circle, changing course every hundred miles or approximately every hour. I had decided to replace the weight of a navigator with extra fuel, and this gave me about three hundred miles additional range. Although the total distance was 3610 miles, the water gap between Newfoundland and Ireland was only about 1850 miles, and under normal conditions I could have arrived on the coast of Europe over three hundred miles off of my course and still have had enough fuel remaining to reach Paris; or I might have struck the coastline as far north as Northern Scandinavia, or as far south as Southern Spain and landed without danger to myself or the plane, even though I had not reached my destination. With these facts in view, I believed the additional reserve of fuel to be more important on this flight than the accuracy of celestial navigation. For the flight from San Diego to St. Louis and New York I carried maps of the individual states and one of the United States with the course plotted on each. For the flight from New York to Paris I had two hydrographic charts of the North Atlantic Ocean containing the great circle course and its bearing at intervals of one hundred miles. In addition to these charts, I had a map of each state, territory and country passed over. This included maps of Connecticut, Rhode Island, Massachusetts, Nova Scotia, Newfoundland, Ireland, England and France. Also a map of Europe. I expected to be able to locate my position approximately on the coast of Europe by the terrain. Ireland is somewhat mountainous; England rather hilly on the southern end; France is a lowland along the coast; Spain is mountainous. Therefore the coastline should indicate the country, and my accurate position could be obtained by the contours of that coastline and by the position of towns, rivers and railroads.