Three weeks' old chicks which had been deprived of direct sunlight and fed on a rachitic diet, were placed behind common glass and glass substitutes for four weeks. Those behind glass made an average gain of 180 per cent, while the groups behind the substitutes made gains of 300 per cent and 250 per cent. All outward appearances of rickets had disappeared among those behind the glass substitutes, while the disease was in evidence in the case of those behind glass.
Proceedings of the Iowa Academy of Science
©1925 Iowa Academy of Science, Inc.
Crum, L. V. and Woodrow, J. W.
"The Growth of Chickens as Effected by the Sunlight Transmitted through Glass Substitutes,"
Proceedings of the Iowa Academy of Science, 32(1), 378-378.
Available at: https://scholarworks.uni.edu/pias/vol32/iss1/77