Show BIG FACTOR IN incubation lack of ventilation given as dause causa for fo many Fallu failures ees in artificially hatched eggs tho the question of ther cause or causes of the lower hatching percentage that commonly ionly characterizes artificial incubation cu when compared with results obtained when eggs egge are sot act under liens hens la Is a matter about which there Is considerable conjecture but little definite knowledge in connection with various theories that have been ad danced and several experiments that have been made it Is perhaps sug bug that investigators have recently inclined to the opinion that un satisfactory results are probably pio bably due in greater measure than la Is generally supposed to an excess of ventilation several authorities nuth orUI ca are mentioned in support of the statement that there to la a larger amount of carbon dl di oxide in tho the air surrounding tho the eggs that are naturally hatched than lit in a well ventilated incubator and tho question la Is raised as to whether and to what extent it may bo be art an essential factor in incubation |