On May 18, 1917, the day the law was enacted by congress, no advocate of preparedness could with confidence have forecasted the success of it. There were many who feared the total failure of it. The history of the United States disclosed a popular adherence to the principle of voluntary enlistment, if not a repudiation of the principle of selection or compulsory military service. It was to be expected that many people would look upon the law as highly experimental; as an act that, if it did not produce grave disorders in the country, would fall short of the results for which it was intended. It was fortunate for the country at this time, that the military establishment possessed in the person of General Crowder, one who had made a special study of selective drafts and other forms of compulsory service, not alone in this country, but throughout the nations of the world and back to the beginning of recorded history. He had become as familiar with all phases of it as though it had been a personal hobby and lifetime pursuit. The law was extremely plain and permitted of no guessing or legal quibbling over its terms. It boldly recited the military obligations of citizenship. It vested the president with the most complete power of prescribing regulations calculated to strike a balance between the industrial, agricultural and economic needs of the nation on the one hand and the military need on the other. Within 18 days between May 18, when the law was approved, and June 5, the day the president had fixed as registration day, a great, administrative machine was built. Practically the entire male citizenship of the United States within the age limits fixed by law, twenty-one to thirty years inclusive, presented itself at the 4,000 enrollment booths with a registered result of nearly 10,000,000 names. The project had been so systematized that within 48 hours almost complete registration returns had been assembled by telegraph in Washington. The order in which the ten-million registrants were to be called was accomplished on July 20 by a great central lottery in Washington. The boards proceeded promptly to call, to examine physically and to consider claims for exemption of over one and one half million men, a sufficient number to fill the first national quota of 687,000. Thus in less than three and one-half months the nation had accepted and vigorously executed a compulsory service law.