VENTILATION
Most pigeon-breeders keep their houses closed too tight during the winter. If cloth is used in the windows instead of glass, there will be good ventilation all the time as the muslin used for the windows allows the air to get in and keeps it pure inside; but where glass is used, the fly holes should be left open nearly every night during the winter or the air will become so impure that it will be likely to breed disease. Pigeons when they are not breeding, do not mind cold weather, but breeding birds should have a tight house on account of the squabs. See to it that the ventilation is attended to.