Planes, however, are a small item compared with some of the other materials procured with the $720,000,000. The American industry produced 30,000 aviation engines before the armistice and more than 11,000 afterwards on war orders during the termination of the industry--the exact figure, representing the total war production, being 41,590. Of these, 20,478 were Liberty engines, 15,572 of which were produced before November 30, 1918. The Liberty engines alone represented over 8,000,000 horsepower. In addition, from the $720,000,000 spent, we bought several thousand aviation engines in Europe. In all we received approximately 45,000 engines for our money. At $6,000 apiece--a fair average price--this procurement accounted for $270,000,000 of the money. Planes and engines together accounted for $384,000,000, or more than half the total expenditure. This was all value received. But we have still to consider many important items of expense necessary to the prosecution of an air project such as ours was. It took, for instance, $190,000,000 to maintain the Air Service of the American Expeditionary Forces. The appropriation procured 1,100 balloons both before and after the armistice, at a cost, say, of $11,000,000. As we have noted above, $75,000,000 went into buildings for the Air Service in this country, another great sum into motor trucks, still another into fuel and lubricating oils, and upwards of $80,000,000 into the development of raw materials for airplane manufacture--spruce, dope, and fabric. This last was a necessary and justifiable expenditure, in that it sustained the airplane industry, not only of the United States, but of the principal Allies as well. Too, the development of raw materials was on a scale which anticipated great expansion of the manufacture of airplanes in 1919 and 1920. And so we can go, item by item, through the list of sub-enterprises in the aviation project and find that we received great value for our money and that almost the only wastes were the to-be-expected war wastes, largely due to our unpreparedness for war. These wastes were represented in the high prices paid for materials produced in such a hurry on such a scale. These high unit prices, of course, took care of the cost of creating almost the whole manufacturing equipment of the industry. However, we secured the materials.