41 



cubators, out-door brooders and coops lias comprised the equipment. 

 The poultry plant is located in the immediate vicinity of plots used 

 in field experiments. It has accordingly been necessary to keep the 

 fowls in close confinement practically all the time. In a few instan- 

 ces chickens when ready to leave the brooders have been placed on 

 private farms until they reached laying maturity. Fowls of the fol- 

 lowing breeds have been used : Light Brahma, Minorca, Barred 

 Plymouth Rock and White Wyandotte. During the greater part of 

 the time, we have used fowls of the last two breeds. In the experi- 

 niants where the influeiiee of the treatment adopted on egg produc- 

 tion was the object in view, we have usually used pullets of our own 

 raising. In a few instances, we have purchased the fowls used. We 

 have almost invariably placed twenty pullets in each house at the 

 beginning of an experiment and usually have kept with them two 

 cockerels of the same breed. In a few instances, we have used some 

 year old hens on account of not having a sufficient number of pul- 

 lets. In every instance, the fowls in flocks which were to be com- 

 pared one with the other were most carefully matched bird by bird as 

 regards all points which could be detected by a very close examina- 

 tion, including the following : weight, size of bone, general conforma- 

 tion, age and degree of maturity. In most cases, the flocks which 

 were to be compared have been fed and treated in every particular 

 alike for a short period previous to the beginning of the experiment, 

 for the purpose of determining whether the conditions as indicated 

 by the number of eggs produced appeared to be equal. In short, 

 no precaution which suggested itself to us as essential to ensure 

 reliable results has ever been neglected. 



Connected with the houses and on the south side of them are 

 yards of precisely equal area (87 square yards per house) for each. 

 The soil in these yards has been frequently stirred in order to keep 

 it fresh throughout the summer season. It should be understood that 

 in every case the general conditions essential for egg production 

 have been as good as we could make them. The fowls have been 

 provided with a dust bath. The scratching shed has been kept deeply 

 covered .with clean litter. The fowls have always had a plentiful 

 supply of pure water. They have also always had access to shells 

 and grit. Every year before a new lot of fowls has been put into 

 the houses they have undergone a thorough cleaning and disinfec- 

 tion and care has been taken throughout the year to keep both the 



