ii.—THE ABSORPTION AND DESORPTION OF WATER BY SODA-BOILED COTTON AT 25°C

Abstract

A more trustworthy method than that previously employed,¹⁰ and one applicable at all humidities, has been devised for determining the moisture content of soda-boiled cotton at 25°C. The results obtained again show that the curve connecting the moisture content with humidity of cotton which becomes wetter in the particular atmosphere (the absorption curve) lies lower than the curve for cotton which becomes drier (the desorption curve). Contrary to previous statements, however, these curves do not meet at zero humidity but at a point corresponding with 1.8% relative humidity. Nor do the curves meet at 100% R.H. An explanation of this phenomenon is offered which depiends on a theory of the capillary structure of cotton not inconsistent with botanical views. The moisture content of an incompletely dried or incompletely saturated cotton at a particular humidity may lie on any point between the two curves At 100% R.H. the moisture content of soda-boiled cotton is 22.6 percent.