32 
Journal of Agricultural Research 
Vol. XXVII, No. I 
the gases by water. The bottle was closed with a stopper containing a 
tube (t) extending to the bottom of the bottle, and with another tube 
extending from the top of the bottle B to the desiccator C containing the 
apples under test. A siphon from A entered the top of the tube t, which 
delivered under the oil in B. As water flowed through this siphon into 
the bottom of bottle B, the contained gases passed out and through the 
desiccator C. They were delivered into the bottom of C, and escaped 
through a capillary opening in the top of C. 
Fig. is.— Apparatus for determining the influence of COs pressure upon the rate of ripening of apples. 
In order to determine whether or not any variation found was due to 
C0 2 present rather than to a deficiency of 0 2 , the 0 2 content of the atmos¬ 
phere in all tests was kept at approximately 20 per cent, or normal air 
concentration. C0 2 concentrations were varied from o to 50 per cent. 
Some variations occurred in the rate of flow of the gas through the 
desiccators containing the apples. In all cases, however, about 18 liters 
of gas passed through per 24 hours, so there were never more than slight 
accumulations of C 0 2 or deficiencies in 0 2 due to the respiration of the 
fruit. 
Two sets of experiments were run, one on Winesap and one on Delicious 
apples. Pressure tests, to determine the relative rates of softening, were 
made on a representative sample of the fruit at the beginning of the test 
and on all the various lots at the end of the test. Acidity determinations 
were also made on all lots. Data for Winesap apples are recorded in 
Table X. 
