Of bias in the interpretation of results all publications are more or less saturated. A reading of the Chapter on Incubation will illustrate this. A common error of this kind is the omission of facts necessary to fully explain results. Items of costs are invariably omitted or minimized. Food cost alone is usually mentioned in figuring experimenting station poultry profits, which statement will undoubtedly cause a sad smile to creep over the face of many a "has-been" poultryman. The writer remembers an incident from his college days which illustrates the point in hand. Let it first be remarked that this was on the new lands of the trans-Missouri Country, where manure had no more commercial value than soil, and is freely given to those who will haul it away. The professor at the blackboard had been figuring up handsome profits on a type of dairying towards which he wits very partial. The figures showed a goodly profit, but the biggest expense item--that of labor--was omitted. One of the students held up his hand and inquired after the labor bill. "Oh," said the smiling professor, "The manure will pay for the labor." When the class adjourned, the student remarked: "They say figures won't lie, but a liar will figure." The third way in which experiments are made worthless is by the introduction of factors other than the one being tested. This may be done by chance, and the conductor not realize the presence of the other factor, or the varying factors may be introduced intentionally under the belief that they are negligible. Of the first case an instance may be cited of the placing of two flocks in a house, one end of which is damper than the other, the accidental introduction into one flock of a contagious disease, or one flock being thrown off feed by an excessive feed of greens, etc., etc. These factors that influence pens of birds greatly add to the error of the law of chance. In fact it amounts to the same thing on a larger scale. For this reason not only are many individuals, but many flocks, many locations, and many years needed to prove the superiority of the contrasted methods. The criticisms in the following section will amply illustrate the case of foreign factors being unwisely introduced into an experiment. The Egg Breeding Work at the Maine Station. As is well known the Maine Station was for years considered by all poultrymen to be doing a great and beneficial work in breeding for increased egg production. Up until the fall of 1907, the poultrymen of the country were of the opinion that this work was in every way successful, and a large number of private breeders had taken up the use of trap-nests in an effort to build up the egg production of their fowls.