690 Journal of Agricultural Research \'o;. xn, no. h 



Kolkwitz (1901) found that barley grains containing 19 to 20 per 

 cent of moisture respired 3.69 mgm. of carbon dioxid per kilo in 24 

 hours at summer temperature, while at the same temperature barley 

 containing 14 to 15 per cent of moisture respired 1.4 mgm. per kilo, 

 and 0.35 mgm. per kilo when containing 10 to 12 per cent of moisture. 

 White (1909) found that all cereals gave off appreciable quantities 

 of carbon dioxid when stored in an air-dried condition, the respiration 

 of wheat containing 11.9 per cent of moisture being especially pro- 

 nounced. Wheat dried for eight days at 45° C. did not respire a determin- 

 able quantity of carbon dioxid. 



Babcock (1912) states that respiration is practically suspended in 

 dry seeds and spores, and is most pronounced when vital processes 

 are most active, as during the germination of seeds. The metabolic 

 water produced as respiration proceeds is believed to play an important 

 part in the vital phenomena of the cells. 



Duvel (1904), in studying the vitality of stored seeds, observed that 

 the rate of respiration, as indicated by the carbon-dioxid content of 

 the air in the closed container, was increased on increasing the moisture 

 content of the seed. At the same time there was a marked diminution 

 in the percentage of viable seed. 



Qvam {1906) observed an increased rate of respiration in barley as 

 the percentage of moisture was increased. 



Duvel (1909) held a lot of corn in storage in an elevator bin. The 

 moisture content averaged 17.8 per cent, and the initial temperature 

 on February 17, 1909, was 36° to 40° F., which increased near the surface 

 of the grain to 133° F. on April 27, 1909. The temperature from the 

 middle to the bottom of the bin was only about 40° F. A portion of 

 the hot corn from the top of the bin was artificially dried to an average 

 of 14.57 per cent of moisture. This was put in a car, and as a control 

 a lot of the cool, undried corn from the same bin was put in another 

 car. The latter had an average moisture content of 17.5 per cent. 

 The dried corn remained for 37 days in as good condition as when put 

 in the car, its temperature rising from 57° to 67° F., or a total increase o£ 

 10 degrees. The cool, undried corn began to show signs of deterioration 

 in 23 days, and five days later a point near the surface reached a tem- 

 perature of 122° F. This indicates the increased tendency of the damp 

 grain to heat in storage. 



Shanahan, Leighty, and Boerner {1910) examined cargoes of American 

 corn on arrival at European ports and observed an increased tendency 

 to heat and "go out of condition" as the moisture content increased. 



Duvel and Duval (1913) Studied the temperature changes in carloads 

 of corn containing different percentages of moisture. In one experiment 



