By the early Summer of 1831, Robert McCormick had so improved his Reaper that he gave it a trial in a field of grain. Again it was a failure. It did cut the grain fairly well, but flung it in a tangled heap. As much as this had been done before by other machines, and it was not enough. To cut the grain was only one-half of the problem; the other half of the problem, which up to this time no one had solved, was how to properly handle and deliver the grain after it was cut. [Illustration: FACSIMILES FROM MANUSCRIPT BY MR. McCORMICK GIVING HIS OWN ACCOUNT OF THE ORIGIN OF THE REAPER] By this time Cyrus had become as much of a Reaper enthusiast as his father. Also, he had been studying out the reasons for his father's failure, and working out in his mind a new plan of construction. How this _new plan_ was slowly moulded into shape by his creative fancy is now told for the first time. A manuscript, written by Cyrus H. McCormick himself, and which has not hitherto been made public, gives a complete description of the process of thought by which he became the inventor of the first practical Reaper. This account, it may be said in explanation, was written by Mr. McCormick shortly before the Chicago fire of 1871. It was to be published at that time, and was in type when the fire came and left not a vestige of the printery. The original manuscript was preserved; but the labor of rebuilding his factory prevented him from carrying out his original design. He wholly forgot his authorship in the troubles of his city; and so his own story of his invention lay untouched among the private papers of the family for thirty-eight years. "Robert McCormick," says this document, "being satisfied that his principle of operation could not succeed, laid aside and abandoned the further prosecution of his idea." He had labored for fifteen years to make a Reaper that would reap, and he had failed. At this point Cyrus took up the work that his father had reluctantly abandoned. He had never seen or heard of any Reaper experiments except those of his father; but he believed he saw a better way, and "devoted himself most laboriously to the discovery of a _new principle of operation_." He showed his originality at the outset by beginning where his father and all other Reaper inventors had left off,--with the cutting of grain that lay in a fallen and tangled mass. He faced the problem worst end first. The Reaper that would cut such grain, he believed, must first separate the grain that is to be cut from the grain that is left standing. It must have at the end of its knife a curved arm--a _divider_. This idea was simple, but in the long history of harvesting grain no one had thought of it before.