In clearing away the useless popular notions, the scientists themselves have not been free from their influence, especially when they seemed to agree with accepted scientific theory. Many, indeed, are the 'coons in poultry science that have been seen because they were being looked for. As a partial explanation it should be said that men available for scientific poultry work are very scarce. Poultry keepers schooled in the University of the Poultry Yard have no conception of scientific methods, and would explain experimental results by a theory that would fail to fit elsewhere. The available scientists on the other hand are seldom poultrymen. Among the first men to take up animal husbandry work of all kinds, were the veterinarians. For years the only poultry publications put out by the U.S. Government were by veterinarians. These dust covered volumes with their five color plates of the fifty-seven varieties of tapeworms, still rest on the shelves of public libraries, a monument to the time when the practical poultryman knew only things that weren't so, and the scientific poultryman knew only things that were useless. The first general law that all experimenters should know and the ignorance of which has caused and still causes the waste of the major portion of experimental brains and money, we will call the "Law of Chance." Let the reader who is not familiar with such things take two pennies and toss them upon the table. They are both heads up. He tosses them again, one comes heads, the other tails. The third time repeats the second. The fourth both come tails. The law of chance says this is correct. Heads should appear 25 per cent., tails 25 per cent., and mixed 50 per cent. of the time. Now let the reader try this in a lot of twelve tosses. Does it prove the law? Try it again. Are all lots alike? Now pitch a hundred times, then pitch pennies all day. By night the law will be so near proven that the experimenter will be willing to concede its validity. Now suppose the lots of twelve tosses, each were lots of twelve hens, one Plymouth Rocks, the other Wyandottes, or one fed corn and the other wheat. The law of chance clearly proves that the larger number of unites, the nearer the theoretical truths will be the experimental results. Note, however, that small lots may by chance be as near the truth as large lots. In practice two grave errors are made: First, conclusions are drawn from small lots compared with each other; second, conclusions are drawn from large lots compared with small lots. In the first case both may be off; in the latter case the small one may be off. Examples of the first error are to be found in the scores of contradicting breed and feed tests, that were published in the early days of poultry research. The second error is exemplified in the Ontario experiments in incubation, to which reference has already been made.